KR102687743B1 - Single photon detection element, single photon detector, single photon detector array - Google Patents

Abstract

A single photon detection element is provided on a first well having a first conductivity type, a second well having a second conductivity type different from the first conductivity type, and a second well. A first depletion forming region having a conductivity type of 1, a main depletion region provided between the first well and the second well, and a first sub-depletion region provided between the second well and the first depletion forming region, Well 1 and the first depletion formation region are spaced apart from each other by the second well.

Description

Single photon detection element, single photon detector, and single photon detector array {SINGLE PHOTON DETECTION ELEMENT, SINGLE PHOTON DETECTOR, SINGLE PHOTON DETECTOR ARRAY}

The present disclosure relates to single photon detection devices, single photon detectors, and single photon detector arrays.

An avalanche photodiode (APD) is a solid-state photodetector in which a high bias voltage is applied to the pn junction to provide high first-stage gain due to avalanche multiplication. When an incident photon with enough energy to emit an electron reaches the photodiode, an electron-hole pair (EHP) is created. A high electric field rapidly accelerates the photo-generated electrons toward the (+) side, and additional electron-hole pairs are created one after another through impact ionization by these accelerated electrons. All electrons are accelerated toward the anode. Similarly, holes are rapidly accelerated toward (-) and cause the same phenomenon. This process repeats, leading to an output current pulse and avalanche multiplication of photogenerated electrons. Therefore, APDs are semiconductor-based devices that operate similarly to photomultiplier tubes. A linear mode APD is an effective amplifier that sets the gain by controlling the bias voltage and can obtain tens to thousands of gains in linear mode.

A Single Photo Avalanched Diode (SPAD) is an APD whose p-n junction is biased above its breakdown voltage to operate in Geiger mode, where a single incident photon triggers the ongoing avalanche phenomenon. ) and can generate a very large current, thereby obtaining a current pulse that can be easily measured with a quenching resistance or circuit. In other words, SPADs operate as devices that generate large current pulses compared to linear mode APDs whose gain may not be sufficient at low light intensities. After triggering the avalanche, a quenching resistor or circuit is used to reduce the bias voltage below the breakdown voltage to quench the avalanche process. Once quenched, the bias voltage is raised again above the breakdown voltage to reset the SPAD for detection of another photon (known to re-bias the SPAD).

APD or SPAD may have electrons generated by surface defects. Electrons generated by surface defects can enter the APD or SPAD and multiply. Accordingly, a noise signal may be generated.

The problem to be solved is to provide a single photon detection device with low noise.

The problem to be solved is to provide a single photon detector with low noise.

However, the problem to be solved is not limited to the above disclosure.

In one aspect, a first well having a first conductivity type; a second well provided on the first well and having a second conductivity type different from the first conductivity type; a first depletion formation region provided on the second well and having the first conductivity type; a main depletion region provided between the first well and the second well; and a first sub-depletion region provided between the second well and the first depletion formation region, wherein the first well and the first depletion formation region are spaced apart from each other by the second well. A device may be provided.

a second depletion formation region provided on an opposite side of the second well with the first well interposed therebetween; and a second sub-depletion region provided between the second depletion formation region and the first well, wherein the second depletion formation region may have the second conductivity type.

A first contact region electrically connected to the first well; wherein the first contact region is spaced apart from the second well, has the first conductivity type, and the doping concentration of the first contact region is It may be higher than the doping concentration of the first well.

A relaxation region provided between the first contact region and the first well, wherein the relaxation region has the first conductivity type, and the doping concentration of the relaxation region is lower than the doping concentration of the first contact region. It can be low.

It further includes a second contact region electrically connected to the second well, wherein the second contact region has the second conductivity type, and the doping concentration of the second contact region is lower than the doping concentration of the second well. It can be high.

The second contact region and the first depletion formation region may contact each other.

The second contact region and the first depletion formation region may be spaced apart from each other.

It may further include a guard ring area provided on a side of the second well, wherein the guard ring area may have the second conductivity type.

The guard ring area may surround the second well.

The first well may extend from the bottom of the second well to the side of the second well.

It may further include a third well surrounding the first well and the second well, wherein the third well may have the first conductivity type.

a second depletion formation region provided opposite the first well to the third well; and a third sub-depletion region provided between the second depletion formation region and the third well, wherein the second depletion formation region may have the second conductivity type.

It may further include a third contact area provided on the third well and spaced apart from the second well, wherein the third contact area may have the first conductivity type.

The doping concentration of the third well may be lower than the doping concentration of the first well.

The third well may contact a side of the second well.

In one aspect, a single photon detection device that receives light and generates an electrical signal; a control layer that processes the electrical signals; and a lens unit that receives the light from the outside and focuses it on the single-photon detection device, wherein the single-photon detection device includes a first well having a first conductivity type and provided on the first well, A second well having a second conductivity type different from the first conductivity type, a first depletion formation region provided on the second well and having the first conductivity type, between the first well and the second well. A main depletion region provided in and a first sub-depletion region provided between the second well and the first depletion formation region, wherein the first well and the first depletion formation region are formed by the second well. Single photon detectors spaced apart from each other may be provided.

The control layer may be disposed between the single photon detection element and the lens unit.

The single photon detection element may be disposed between the control layer and the lens unit.

The first depletion formation region may be disposed closer to the control layer than to the lens unit.

The control layer includes: an insulating layer; wires; and circuits; wherein the wires electrically connect the first well and the second well to the circuits, and the circuits may include a quenching circuit and a readout circuit.

The circuit may include a recharge circuit, memory, amplifier circuit, counter, and gate circuit.

It may include at least one of a color filter, a bandpass filter, and an anti-reflection coating provided between the single photon detection element and the lens unit.

In one aspect, a plurality of single photon detection elements that receive light and generate an electrical signal; a control layer that processes the electrical signals; and a plurality of lenses that receive the light from the outside and focus each of the plurality of single-photon detection elements on the plurality of single-photon detection elements, wherein each of the plurality of single-photon detection elements includes: a first well having a first conductivity type; a second well provided on the first well and having a second conductivity type different from the first conductivity type; a first depletion formation region provided on the second well and having the first conductivity type; A main depletion region provided between the first well and the second well, and a first sub-depletion region provided between the second well and the first depletion formation region, wherein the first well and the first The depletion formation region may be provided with an array of single photon detectors spaced from each other by the second well.

The present disclosure can provide a single photon detection device with low noise.

The present disclosure can provide a single photon detector with low noise.

However, the effect of the invention is not limited to the above disclosure.

1 is a cross-sectional view of a single photon detection device according to an exemplary embodiment.
FIG. 2 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.
FIG. 3 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.
FIG. 4 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.
Figure 5 is a top view of the single photon detection device of Figure 1 according to an example embodiment.
FIG. 6 is a top view of the single photon detection device of FIG. 1 according to an example embodiment.
FIG. 7 is a top view of the single photon detection device of FIG. 1 according to an example embodiment.
FIG. 8 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.
Figure 9 is a cross-sectional view of a single photon detection device according to an example embodiment.
FIG. 10 is a top view of the single photon detection device of FIG. 9 according to an example embodiment.
Figure 11 is a cross-sectional view of a single photon detection device according to an example embodiment.
FIG. 12 is a top view of the single photon detection device of FIG. 11 according to an example embodiment.
Figure 13 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 14 is a top view of the single photon detection device of Figure 13 according to an example embodiment.
Figure 15 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 16 is a top view of the single photon detection device of Figure 15 according to an example embodiment.
Figure 17 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 18 is a cross-sectional view of a single photon detector according to an example embodiment.
Figure 19 is a cross-sectional view of a single photon detector according to an example embodiment.
Figure 20 is a top view of a single photon detector array according to an example embodiment.
FIG. 21 is a cross-sectional view taken along line II′ of FIG. 20.
Figure 22 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 23 is a top view of the single photon detection device of Figure 22 according to an example embodiment.
Figure 24 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 25 is a top view of the single photon detection device of Figure 24 according to an example embodiment.
Figure 26 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 27 is a top view of the single photon detection device of Figure 26 according to an example embodiment.
Figure 28 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 29 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 30 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 31 is a cross-sectional view of a single photon detection device according to an example embodiment.
Figure 32 is a block diagram for explaining an electronic device according to an example embodiment.
33 and 34 are conceptual diagrams showing a case where a LiDAR device is applied to a vehicle according to an exemplary embodiment.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the attached drawings. In the following drawings, the same reference numerals refer to the same components, and the size of each component in the drawings may be exaggerated for clarity and convenience of explanation. Meanwhile, the embodiments described below are merely illustrative, and various modifications are possible from these embodiments.

Hereinafter, the term “on” may include not only what is directly above in contact but also what is above without contact.

Singular expressions include plural expressions unless the context clearly dictates otherwise. Additionally, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

Additionally, terms such as “... unit” used in the specification refer to a unit that processes at least one function or operation.

1 is a cross-sectional view of a single photon detection device according to an exemplary embodiment.

Referring to Figure 1, a single photon detection element 1 may be provided. The single photon detection element 1 may comprise a single photon avalanche diode (SPAD). In one example, a single photon avalanche diode (SPAD) may be referred to as a Geiger-mode avalanche diode (Geiger-mode APD, G-APD). The single photon detection device 1 includes a first well 110, a second well 120, a first contact region 114, a first relaxation region 112, a first depletion formation region 130, and a second contact. It may include a region 122 and a second depletion formation region 100. First well 110, second well 120, first contact region 114, first relaxation region 112, first depletion formation region 130, second contact region 122, and second The depletion formation region 100 may be formed by doping a semiconductor substrate (eg, a p-type or n-type silicon (Si) substrate). For example, the semiconductor substrate may be a p-type or n-type epitaxial layer. The second depletion formation region 100 may be formed by an epitaxial growth process.

The first well 110 may have a first conductivity type. When the conductivity type of the semiconductor substrate is p-type, the conductivity type of the first well 110 may be n-type. When the conductivity type of the first well 110 is n-type, the first well 110 is formed on a silicon (Si) substrate with a group 5 element (e.g., phosphorus (P), arsenic (As), antimony (Sb), etc. ), it may be formed by injecting a group 6, or group 7 element as an impurity. When the conductivity type of the semiconductor substrate is n-type, the conductivity type of the first well 110 may be p-type. When the conductivity type of the first well 110 is p-type, the first well 110 is formed on a silicon (Si) substrate with a Group 3 element (e.g., boron (B), aluminum (Al), gallium (Ga), It may be formed by implanting indium (In, etc.) or a group 2 element as an impurity. For example, the doping concentration of the first well 110 may be about 1x10 ¹⁴ to 1x10 ¹⁹ cm ^-3 . In one example, the doping concentration of the first well 110 may have a gradient that decreases toward the top of the first well 110. In another example, the first well 110 may have a uniform doping concentration.

The second well 120 may have a second conductivity type different from the first conductivity type. When the conductivity type of the first well 110 is n-type, the conductivity type of the second well 120 may be p-type. When the conductivity type of the first well 110 is p-type, the conductivity type of the second well 120 may be n-type. For example, the doping concentration of the second well 120 may be about 1x10 ¹⁵ to 1x10 ¹⁸ cm ^-3 .

A first main depletion region 30 may be formed in an area adjacent to the interface between the first well 110 and the second well 120. When a reverse bias is applied to the single photon detection element 1, a strong electric field may be applied to the first main depletion region 30. For example, if the single-photon detection device 1 operates as a single-photon avalanche diode (SPAD), the maximum intensity of the electric field may be about 1x10 ⁵ to 1x10 ⁶ V/cm. Since electrons may be multiplied by the electric field of the first main depletion region 30, the first main depletion region 30 may be referred to as a multiplication region.

A first contact area 114 may be provided on the first well 110. The first contact area 114 may be electrically connected to a circuit external to the single photon detection element 1. For example, a voltage may be applied to the first well 110 from a circuit external to the single photon detection element 1 through the first contact region 114 . A first contact area 114 may be provided on a side of the second well 120 . The first contact area 114 may surround the second well 120 . For example, the first contact area 114 may have a ring shape extending along the side of the second well 120 . The first contact area 114 may be spaced apart from the second well 120 . The first well 110 may extend into the area between the first contact area 114 and the second well 120. For example, the area between the first contact area 114 and the second well 120 may be filled with the first well 110 . The first contact region 114 may have a first conductivity type. The doping concentration of the first contact region 114 may be higher than that of the first well 110 . For example, the doping concentration of the first contact region 114 may be about 1x10 ¹⁵ to 1x10 ²² cm ^-3 .

A first relief area 112 may be provided between the first contact area 114 and the first well 110. The first relief area 112 may be electrically connected to the first contact area 114 and the first well 110. The first relaxation region 112 may alleviate the difference between the bandgap of the first contact region 114 and the bandgap of the first well 110. A first relief area 112 may be provided on a side of the second well 120 . The first relief area 112 may surround the second well 120 . For example, the first relief area 112 may have a ring shape extending along the direction in which the side of the second well 120 extends. A first relief area 112 may be provided below the first contact area 114 . For example, the side surfaces of the first relief area 112 may be coplanar with the side surfaces of the first contact area 114 . The first relief area 112 may be spaced apart from the second well 120 . The first well 110 may extend into the area between the first relief area 112 and the second well 120. For example, the area between the first relief area 112 and the second well 120 may be filled with the first well 110 . The first relief area 112 may be formed deeper than the second well 120 . For example, the bottom surface of the first relaxation region 112 may be spaced farther from the top surface of the single photon detection device 1 than the bottom surface of the second well 120 . The first relaxation region 112 may have a first conductivity type. The doping concentration of the first relaxation region 112 may be lower than that of the first contact region 114 and may be higher than that of the first well 110 . For example, the doping concentration of the first relaxation region 112 may be about 1x10 ¹⁵ to 1x10 ¹⁹ cm ^-3 .

A first depletion formation region 130 may be provided on the second well 120. The first depletion formation region 130 may have a first conductivity type. The doping concentration of the first depletion formation region 130 may be higher than that of the first well 110 . For example, the doping concentration of the first depletion formation region 130 may be about 1x10 ¹⁵ to 1x10 ²² cm ^-3 .

The first sub-depletion region 10 may be formed in an area adjacent to the interface between the first depletion formation region 130 and the second well 120. The first sub-depletion region 10 reduces or substantially prevents electrons or holes other than electron-hole pairs generated by photons within the single-photon detection element 1 from being provided to the first main depletion region 30. can do. For example, electrons or holes other than the electron-hole pairs generated by photons within the single-photon detection device 1 may cause defects on the surface of the single-photon detection device 1 adjacent to the first sub-depletion region 10. It may be created by . The first sub-depletion region 10 can reduce or substantially prevent electrons or holes from moving to the first main depletion region 30 due to surface defects of the single-photon detection device 1.

A second contact area 122 may be provided on the second well 120. The second contact area 122 may be electrically connected to a circuit external to the single photon detection element 1. For example, if the single photon detection device 1 is a single photon avalanche diode (SPAD), the single photon detection device 1 uses a quenching resistor or circuit through the second contact region 122. or circuit) and other pixel circuits. A quenching resistor or circuit can stop the avalanche effect and allow the single-photon avalanche diode (SPAD) to detect another photon. Other pixel circuits may be composed of a reset or recharge circuit, memory, amplification circuit, counter, gate circuit, etc., and transmit signal current to the single photon detection element 1 or from the single photon detection element 1. Signal current can be received. The second contact region 122 may be provided on a side of the first depletion formation region 130 . The second contact region 122 may surround the first depletion formation region 130 . For example, the second contact region 122 may have a ring shape extending along the side of the first depletion formation region 130 . The second contact region 122 may have an inner surface adjacent to the first depletion formation region 130 and an outer surface provided on an opposite side of the inner surface. In one example, the second contact region 122 may contact the first depletion formation region 130 . The inner surface of the second contact region 122 may contact the side surface of the first depletion formation region 130. In one example, the second contact region 122 may be spaced apart from the first depletion formation region 130 . For example, the inner surface of the second contact region 122 may face the first depletion formation region 130 but may be spaced apart from each other. The second contact area 122 may have a second conductivity type. The doping concentration of the second contact region 122 may be higher than that of the second well 120 . For example, the doping concentration of the second contact region 122 may be about 1x10 ¹⁵ to 1x10 ²² cm ^-3 . The outer surface of the second contact area 122 may be covered by the second well 120. In other words, the second well 120 may extend onto the outer surface of the second contact area 122.

The second depletion formation region 100 may be provided on the opposite side of the second well 120 with the first well 110 interposed therebetween. The second depletion formation region 100 may have a second conductivity type. For example, the doping concentration of the second depletion formation region 100 may be about 1x10 ¹⁴ to 1x10 ²² cm ^-3 .

A second sub-depletion region 20 may be formed in an area adjacent to the interface between the second depletion formation region 100 and the first well 110. The second sub-depletion region 20 reduces or substantially prevents electrons or holes other than electron-hole pairs generated by photons within the single-photon detection element 1 from being provided to the first main depletion region 30. can do. For example, electrons or holes other than the electron-hole pairs generated by photons within the single-photon detection device 1 may be caused by surface defects of the single-photon detection device 1 adjacent to the second sub-depletion region 20. It may be created by The second sub-depletion region 20 can reduce or substantially prevent electrons or holes from moving to the first main depletion region 30 due to surface defects of the single-photon detection device 1.

The single photon detection element 1 may have surface defects. Electrons or holes may be generated due to defects on the surface of the single photon detection element 1. When electrons or holes generated by surface defects move to the first main depletion region 30, these electrons or holes may be multiplied and cause noise signals to be generated. That is, even though photons are not provided to the single photon detection element 1, the single photon detection element 1 can generate a noise signal.

The first sub-depletion region 10 and the second sub-depletion region 20 of the present disclosure allow electrons or holes generated by surface defects of the single-photon detection element 1 to move to the first main depletion region 30. can be reduced or substantially prevented. Accordingly, a single photon detection element 1 with small noise can be provided. It is also possible to implement both the first sub-depletion region 10 and the second sub-depletion region 20 or only one of them.

FIG. 2 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 2, the single photon detection element 1a(1) may have a circular shape. Specifically, the first depletion formation region 130 may have a circular shape, and the second contact region 122, the first contact region 114, the second well 120, and the first well 110 are It may have a circular ring shape. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

FIG. 3 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 3, the single photon detection element 1b(1) may have a square shape. Specifically, the first depletion formation region 130 may have a square shape, and the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have a square shape. It may have a square ring shape. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

FIG. 4 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 4, the single photon detection element 1c(1) may have a square shape with rounded corners. Specifically, the first depletion formation region 130 may have a square shape with rounded corners, and the second contact region 122, the second well 120, the first well 110, and the first contact Area 114 may have a square ring shape with rounded corners. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

Figure 5 is a top view of the single photon detection device of Figure 1 according to an example embodiment.

Referring to FIG. 5, the single photon detection element 1d(1) may have a rectangular shape. Specifically, the first depletion formation region 130 may have a rectangular shape, and the second contact region 122, the second well 120, and the first well 110, and the first contact region 114 may have a rectangular ring shape. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

FIG. 6 is a top view of the single photon detection device of FIG. 1 according to an example embodiment.

Referring to FIG. 6, the single photon detection element 1e(1) may have a rectangular shape with rounded corners. Specifically, the first depletion formation region 130 may have a rectangular shape with rounded corners, and the second contact region 122, the second well 120, the first well 110, and the first contact region (114) may have a square ring shape with rounded corners. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

FIG. 7 is a top view of the single photon detection device of FIG. 1 according to an example embodiment.

Referring to FIG. 7, the single photon detection element 1f(1) may have an elliptical shape. Specifically, the first depletion formation region 130 may have an oval shape, and the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have an oval shape. It may have an oval shape. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

FIG. 8 is a top view of the single photon detection device of FIG. 1 according to an exemplary embodiment.

Referring to FIG. 8, the single photon detection element 1g(1) may have an octagonal shape. Specifically, the first depletion formation region 130 may have an octagonal shape, and the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have an octagonal shape. It may have an octagonal ring shape. The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, and the first contact region 114 may have the same center. . The second contact region 122, the second well 120, the first well 110, and the first contact region 114 may be sequentially arranged in a direction away from the first depletion formation region 130.

Figure 9 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 1 may not be described.

Referring to Figure 9, a single photon detection element 2 may be provided. The single photon detection element 2 may comprise a single photon avalanche diode (SPAD). The single photon detection element 2 may be substantially the same as the single photon detection element 1 described with reference to FIG. 1, except for the shape of the first contact region 114 and the first relaxation region 112. .

Unlike what is described with reference to FIG. 1 , the width of the first contact area 114 may be smaller than the width of the first relief area 112 . The first contact area 114 may be located inside the first relief area 112 . Side surfaces of the first contact area 114 may be spaced apart from the outer surface of the first relief area 112 .

First contact area The top surface of the first contact area 114 may be coplanar with the top surface of the first relief area 112 . For example, the top surface of the first contact area 114 may be located between the top surfaces of the first relief area 112.

FIG. 10 is a top view of the single photon detection device of FIG. 9 according to an example embodiment.

Referring to FIG. 10, the single photon detection element 2 may have a circular shape. Specifically, the first depletion formation region 130 may have a circular shape, and the second contact region 122, the second well 120, the first well 110, the first relaxation region 112, and The first contact area 114 may have a circular ring shape. Second contact region 122, second well 120, first well 110, first relaxation region 112, and first contact region 114 will surround first depletion formation region 130. You can. For example, first depletion formation region 130, second contact region 122, second well 120, first well 110, first relaxation region 112, and first contact region 114. ) may have the same center. The second contact region 122, the second well 120, the first well 110, the first relaxation region 112, and the first contact region 114 are oriented away from the first depletion formation region 130. They can be arranged sequentially.

The single photon detection element 2 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3 to 8, the single photon detection element 2 has a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an oval shape. You can have it.

Figure 11 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 1 may not be described.

Referring to Figure 11, a single photon detection element 3 may be provided. The single photon detection element 3 may comprise a single photon avalanche diode (SPAD). The single photon detection element 3 includes a first well 110, a second well 120, a first contact region 114, a first relaxation region 112, a first depletion formation region 130, and a second contact. It may include a region 122, a second depletion formation region 100, and a guard ring region 500. First well 110, second well 120, first contact region 114, first relaxation region 112, first depletion forming region 130, second contact region 122, second depletion The formation region 100 and the guard ring region 500 may be formed on a semiconductor substrate (eg, a p-type or n-type silicon (Si) substrate). For example, the semiconductor substrate may include a p-type or n-type epitaxial layer. The second depletion formation region 100 may be formed by an epitaxial growth process.

First well 110, second well 120, first contact region 114, first relaxation region 112, first depletion formation region 130, second contact region 122, and second The depletion formation region 100 includes a first well 110, a second well 120, a first contact region 114, a first relaxation region 112, and a first depletion formation region, respectively, which are described with reference to FIG. It may be substantially the same as 130, the second contact region 122, and the second depletion formation region 100.

A guard ring area 500 may be provided on the side of the second well 120 . The guard ring area 500 can alleviate concentration of electric fields at the corners of the second well 120 and prevent pre-mature breakdown. The premature breakdown phenomenon occurs in the corner of the second well 120 before a sufficiently large electric field is applied to the first main depletion region 30, and the electric field is concentrated at the corner of the second well 120. It occurs according to The guard ring area 500 can improve the breakdown characteristics of the single photon detection device 3. The guard ring area 500 may surround the second well 120 . For example, the guard ring area 500 may have a ring shape extending along the side of the second well 120 . The guard ring area 500 may directly contact the second well 120 . The guard ring area 500 may be spaced apart from the first contact area 114 and the first relief area 112 . The first well 110 may extend to the area between the guard ring area 500 and the first relief area 112 and the area between the guard ring area 500 and the first contact area 114. For example, the area between the guard ring area 500 and the first relief area 112 and the area between the guard ring area 500 and the first contact area 114 may be filled with the first well 110. . The guard ring area 500 may protrude from the interface between the second well 120 and the first well 110 toward the first well 110 . The guard ring area 500 is not limited to being spaced apart from the first contact area 114 and the first relief area 112. In another example, the guard ring area 500 may directly contact the first contact area 114 and the first relief area 112. The guard ring area 500 may have a second conductivity type. The doping concentration of the guard ring region 500 may be lower than the doping concentration of the second well 120. For example, the doping concentration of the guard ring region 500 may be about 1x10 ¹⁵ to 1x10 ¹⁸ cm ^-3 .

The present disclosure can provide a single photon detection device 3 with small noise and improved breakdown characteristics.

FIG. 12 is a top view of the single photon detection device of FIG. 11 according to an example embodiment.

Referring to FIG. 12, the single photon detection element 3 may have a circular shape. Specifically, the first depletion formation region 130 may have a circular shape, and the second contact region 122, the second well 120, the guard ring region 500, the first well 110, and the second well 120 may have a circular shape. 1 The contact area 114 may have a circular ring shape. The second contact region 122, the second well 120, the guard ring region 500, the first well 110, and the first contact region 114 may surround the first depletion formation region 130. there is. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the guard ring region 500, the first well 110, and the first contact region 114. may have the same center. The second contact region 122, the second well 120, the guard ring region 500, the first well 110, and the first contact region 114 are oriented away from the first depletion formation region 130. Can be arranged sequentially.

The single photon detection element 3 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3 to 8, the single photon detection element 2 has a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an oval shape. You can have it.

Figure 13 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 11 may not be described.

Referring to Figure 13, a single photon detection element 4 may be provided. The single photon detection element 4 is a single photon detection element described with reference to FIG. 11, except for the first depletion formation region 130, the second contact region 122, and the guard ring region 500. It may be substantially the same as 3).

The second contact area 122 may be disposed on the guard ring area 500 . The side surface of the second contact area 122 may be coplanar with the side surface of the guard ring area 500 adjacent thereto. Although it is shown that the entire second contact area 122 is disposed on the guard ring area 500, this is merely an example. In another example, a portion of the second contact area 122 may be disposed on the guard ring area 500 . In another example, the width of the second contact area 122 may be smaller than the width of the guard ring area 500. The second contact area 122 may be located inside the guard ring area 500 . Side surfaces of the second contact area 122 may be spaced apart from the outer surface of the guard ring area 500 .

The second contact region 122 may be spaced apart from the first depletion formation region 130 . A portion of the second well 120 may be disposed between the second contact region 122 and the first depletion formation region 130. However, this is just an example. In another example, the first depletion formation region 130 may extend to contact the second contact region 122 disposed on the guard ring region 500.

As the second contact region 122 is disposed on the guard ring region 500, the first depletion formation region 130 may be provided in a larger area than that described with reference to FIG. 11. Accordingly, the first sub-depletion region 10 may be formed wider than that described with reference to FIG. 11 .

The present disclosure can provide a single photon detection device 4 with small noise and improved breakdown characteristics.

FIG. 14 is a top view of the single photon detection device of FIG. 13 according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 12 may not be described.

Referring to FIG. 14, the single photon detection element 4 may have a circular shape. Unlike what is explained with reference to FIG. 12 , the guard ring area (500 in FIG. 13 ) may be covered by the second contact area 122 .

The single photon detection element 4 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3 to 8, the single photon detection element 4 has a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an oval shape. You can have it.

Figure 15 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 1 may not be described.

Referring to Figure 15, a single photon detection element 5 may be provided. The single photon detection element 5 may comprise a single photon avalanche diode (SPAD). The single photon detection element 5 includes a third well 210, a fourth well 220, a fifth well 216, a third contact region 214, a second relaxation region 212, and a third depletion formation region. 230 , a fourth contact region 222 , and a fourth depletion formation region 200 . Third well 210, fourth well 220, fifth well 216, third contact region 214, second relaxation region 212, third depletion formation region 230, fourth contact region 222 and the fourth depletion formation region 200 may be regions formed by doping a semiconductor substrate (eg, a p-type or n-type silicon (Si) substrate). For example, the semiconductor substrate may include a p-type or n-type epitaxial layer. The third well 210 may be formed by an epitaxial growth process.

Third well 210, fourth well 220, third contact region 214, second relaxation region 212, third depletion formation region 230, fourth contact region 222, and fourth The depletion formation region 200 includes a first well 110, a second well 120, a first contact region 114, a first relaxation region 112, and a first depletion formation region, respectively, which are described with reference to FIG. It may be substantially the same as 130, the second contact region 122, and the second depletion formation region 100.

The fifth well 216 may be provided between the third well 210 and the fourth well 220. The fifth well 216 may be provided on the opposite side of the third depletion formation region 230 with the fourth well 220 interposed therebetween. For example, the fifth well 216 may be provided on the bottom of the fourth well 220. The fifth well 216 may have the same conductivity type as the third well 210. The fifth well 216 may have a first conductivity type. For example, the doping concentration of the fifth well 216 may be about 1x10 ¹⁴ to 1x10 ¹⁸ cm ^-3 . A second main depletion region 32 may be formed in an area adjacent to the interface of the fifth well 216 and the fourth well 220. When a reverse bias is applied to the single photon detection element 5, a strong electric field may be applied to the second main depletion region 32. For example, the maximum intensity of the electric field may be about 1x10 ⁵ to 1x10 ⁶ V/cm. Since electrons may be multiplied by the electric field of the second main depletion region 32, the second main depletion region 32 may be referred to as a multiplication region.

The third sub-depletion region 12 may be formed in an area adjacent to the interface between the fourth well 220 and the third depletion formation region 230. The third sub-depletion region 12 reduces or substantially prevents electrons or holes other than electron-hole pairs generated by photons within the single photon detection element 5 from being provided to the second main depletion region 32. can do. For example, electrons or holes other than the electron-hole pairs generated by photons within the single-photon detection element 5 may be caused by surface defects of the single-photon detection element 5 adjacent to the third sub-depletion region 12. It may be created by The third sub-depletion region 12 can reduce or substantially prevent electrons or holes from moving to the second main depletion region 32 due to surface defects of the single-photon detection element 5.

A fourth sub-depletion region 22 may be formed in an area adjacent to the interface between the fourth depletion formation region 200 and the third well 210. The fourth sub-depletion region 22 reduces or substantially prevents electrons or holes other than electron-hole pairs generated by photons within the single photon detection element 5 from being provided to the second main depletion region 32. can do. For example, electrons or holes other than the electron-hole pairs generated by photons within the single-photon detection element 5 may be caused by surface defects of the single-photon detection element 5 adjacent to the fourth sub-depletion region 22. It may be created by The fourth sub-depletion region 22 can reduce or substantially prevent electrons or holes from moving to the second main depletion region 32 due to surface defects of the single-photon detection element 5.

The single photon detection element 5 may have surface defects. Electrons or holes may be generated by surface defects of the single photon detection element 5. When electrons or holes generated by surface defects move to the second main depletion region 32, these electrons or holes may be multiplied and cause noise signals to be generated. That is, even though photons are not provided to the single photon detection element 5, the single photon detection element 5 can generate a noise signal.

The third sub-depletion region 12 and the fourth sub-depletion region 22 of the present disclosure allow electrons or holes generated by surface defects of the single-photon detection element 5 to move to the second main depletion region 32. can be reduced or substantially prevented. Accordingly, a single photon detection element 5 with small noise can be provided. It is also possible to implement both the third sub-depletion region 12 and the fourth sub-depletion region 22 or only one of them.

Figure 16 is a top view of the single photon detection device of Figure 15 according to an example embodiment.

Referring to FIG. 16, the single photon detection element 5 may have a circular shape. Specifically, the third depletion formation region 230 may have a circular shape, and the fourth contact region 222, the fourth well 220, the third well 210, and the third contact region 214 have a circular shape. It may have a circular ring shape. The fourth contact region 222, the fourth well 220, the third well 210, and the third contact region 214 may surround the third depletion formation region 230. For example, the third depletion formation region 230, the fourth contact region 222, the fourth well 220, the third well 210, and the third contact region 214 may have the same center. . The fourth contact region 222, the fourth well 220, the third well 210, and the third contact region 214 may be sequentially arranged in a direction away from the third depletion formation region 230.

The single photon detection element 5 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3 to 8, the single photon detection element 5 may have a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an elliptical shape. You can.

Figure 17 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 15 may not be described.

Referring to Figure 17, a single photon detection element 6 may be provided. The single photon detection element 6 may comprise a single photon avalanche diode (SPAD). The single photon detection element 6 includes a third well 210, a fourth well 220, a fifth well 216, a third contact region 214, a second relaxation region 212, and a third depletion formation region. 230, and may include a fourth contact area 222. The third well 210 may be formed by an epitaxial growth process.

Unlike what is described with reference to FIG. 15, the single photon detection element 6 may not include the fourth depletion formation region (200 in FIG. 15). Accordingly, the fourth sub-depletion region 22 may not be included.

The third sub-depletion region 12 of the present disclosure is such that electrons or holes generated by defects on the surface of the single-photon detection element 6 adjacent to the third sub-depletion region 12 are transferred to the second main depletion region 32. Movement can be reduced or substantially prevented. Accordingly, a single photon detection element 6 with small noise can be provided.

Figure 18 is a cross-sectional view of a single photon detector according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 1 may not be described.

Referring to FIG. 18, a single photon detector (SE1) may be provided. The single photon detector (SE1) may be a back side illumination (BSI) type image sensor. The single photon detector SE1 may include a single photon detection element 1000, a connection layer 2000, a control layer 2200, and a lens unit 3000. The single photon detection device 1000 may be substantially the same as the single photon detection device 1 described with reference to FIG. 1 . However, this is just an example. In another example, the single photon detection element 1000 is one of the single photon detection elements 2, 3, 4, 5, 6 described above or the single photon detection elements 7, 7-1, 7-2, described later. It may be any one of 8, 8-1, 8-2, 9). The single photon detection device 1000 may include a single photon avalanche diode (SPAD). For convenience of explanation, the single photon detection device 1000 is shown with the top and bottom of the single photon detection device 1 shown in FIG. 1 reversed.

The connection layer 2000 may include an insulating layer 2002 and wires 2100. For example, insulating layer 2002 may include silicon oxide (e.g., SiO ₂ ), silicon nitride (e.g., SiN), silicon oxynitride (e.g., SiON), or combinations thereof. there is.

The wires 2100 may be electrically connected to the first contact area 114 and the second contact area 122 to apply a voltage. The wires 2100 may electrically connect the second contact region 122 and the first depletion formation region 130 or apply the same voltage. In one example, the wires 2100 are formed widely on the single photon detection device 1000 and can be used to increase efficiency by reflecting light. Wires 2100 may connect the first contact area 114 and/or the second contact area 122 with the circuit 2202 .

Control layer 2200 may include circuitry 2202. For example, the control layer 2200 may be a chip on which the circuit 2202 is formed. Although circuit 2202 is shown as one block, this does not mean that circuit 2202 has only one electronic device (eg, one transistor). Circuit 2202 may include various electronic elements as needed. If the single photon detection device 1000 includes a single photon avalanche diode (SPAD), the circuit 2202 may include a quenching resistor or circuit and a readout circuit. A quenching circuit can stop the avalanche effect and allow a single-photon avalanche diode (SPAD) to detect another photon. Other pixel circuits may be composed of a reset or recharge circuit, memory, amplification circuit, counter, gate circuit, etc., and transmit signal current to the single photon detection element 1000 or from the single photon detection element 1000. Signal current can be received. Although circuitry 2202 is shown being provided within control layer 2200, this is exemplary. In another example, circuit 2202 may be located on a semiconductor substrate on which single photon detection device 1000 was formed.

The lens unit 3000 may focus the incident light and transmit it to the single photon detection element 1000. For example, the lens unit 3000 may include a microlens and a Fresnel lens. In one example, the central axis of the lens unit 3000 may be aligned with the central axis of the single photon detection element 1000. The central axis of the lens unit 3000 and the central axis of the single photon detection element 1000 pass through the center of the lens unit 3000 and the center of the single photon detection element 1000, respectively. It may be a virtual axis parallel to the stacking direction of (3000). In one example, the central axis of the lens unit 3000 may be aligned to be misaligned with the central axis of the single photon detection element 1000. When the circuit 2202 is located on a semiconductor substrate on which the single-photon detection device 1000 is formed, or when a pixel isolation structure or separator (not shown) is used, the lens unit 3000 is a single-photon detection device ( 1000) can be implemented larger than that. In one embodiment, a color filter, a bandpass filter, an anti-reflection coating, a 2D nanomaterial, and an organic material are placed between the lens unit 3000 and the single photon detection device 1000. etc. may be formed.

The present disclosure can provide a single photon detector (SE1) with small noise.

Figure 19 is a cross-sectional view of a single photon detector according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 18 may not be described.

Referring to FIG. 19, a single photon detector (SE2) may be provided. The single photon detector (SE2) may be a Front Side Illumination (FSI) type image sensor. The single photon detector SE2 may include a single photon detection element 1000, a connection layer 2000, a separator SL, a circuit 2202, and a lens unit 3000. The single photon detection device 1000 may be substantially the same as the single photon detection device 1000 described with reference to FIG. 18 .

The separator SL may surround the single photon detection device 1000. For example, the separator SL may include silicon oxide, silicon nitride, silicon oxynitride, polycrystalline silicon, low-k dielectric material, metal, or a combination thereof.

The circuit 2202 may be located on the semiconductor substrate on which the single photon detection device 1000 is formed. Circuit 2202 may be substantially the same as circuit 2202 described with reference to FIG. 18 .

A connection layer 2000 may be provided on the single photon detection device 1000 and the separator SL. The connection layer 2000 may include an insulating layer 2002 and wires 2100. The insulating layer 2002 and the wires 2100 may be substantially the same as the insulating layer 2002 and the wires 2100 described with reference to FIG. 18 .

A lens unit 3000 may be provided on the connection layer 2000. The lens unit 3000 may be substantially the same as the lens unit 3000 described with reference to FIG. 18 .

In one embodiment, a color filter, a bandpass filter, an anti-reflection coating, a 2D nanomaterial, an organic material, etc. are placed between the lens unit 3000 and the connection layer 2000. can be formed.

The present disclosure can provide a single photon detector (SE2) with small noise.

Figure 20 is a top view of a single photon detector array according to an example embodiment. FIG. 21 is a cross-sectional view taken along line II' of FIG. 20. For brevity of explanation, content substantially the same as that described with reference to FIG. 18 may not be described.

20 and 21, a single photon detector array (SPA) may be provided. A single photon detector array (SPA) may include single photon detectors (SE) arranged in two dimensions. Each of the single photon detectors SE may include lens units 3000. Single photon detectors (SE) may each define pixels. In Figure 20, boundaries between pixels are indicated by dotted lines. Each of the single photon detectors SE may be substantially identical to the single photon detector SE1 described with reference to FIG. 18 . However, this is not limiting, and each of the single photon detectors SE may be substantially the same as the single photon detector SE2 described with reference to FIG. 19 .

A separation membrane (SL) may be provided between the single photon detectors (SE). The separator SL can prevent the crosstalk phenomenon in which light incident on a pixel is sensed by another pixel adjacent to the pixel. For example, the separator SL may include silicon oxide, silicon nitride, silicon oxynitride, polycrystalline silicon, low-k dielectric material, metal, or a combination thereof.

The present disclosure can provide a single photon detector array (SPA) with small noise.

Figure 22 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 15 may not be described.

Referring to Figure 22, a single photon detection element 7 may be provided. The single photon detection element 7 may comprise a single photon avalanche diode (SPAD). Unlike what is described with reference to FIG. 15 , the single photon detection element 7 may not include the third depletion region (230 in FIG. 15) and the fourth well (220 in FIG. 15). In FIG. 15 , a fourth contact region 222 may be provided in the area where the third depletion region is provided instead of the third depletion region.

The fifth well 216 may be provided below the fourth contact area 222. The fifth well 216 may directly contact the fourth contact area 222 . The fifth well 216 may have a smaller width than the fourth contact area 222 . A third main depletion region 34 may be formed in an area adjacent to the interface between the fifth well 216 and the fourth contact region 222. When a reverse bias is applied to the single photon detection element 7, a strong electric field may be applied to the third main depletion region 34. For example, the maximum intensity of the electric field may be about 1x10 ⁵ to 1x10 ⁶ V/cm. Since electrons may be multiplied by the electric field of the third main depletion region 34, the third main depletion region 34 may be referred to as a multiplication region.

A fourth sub-depletion region 22 may be formed in an area adjacent to the interface between the fourth depletion formation region 200 and the third well 210. The fourth sub-depletion region 22 reduces or substantially prevents electrons or holes other than electron-hole pairs generated by photons within the single photon detection element 7 from being provided to the third main depletion region 34. can do. For example, electrons or holes other than the electron-hole pairs generated by photons within the single-photon detection element 7 may cause surface defects of the single-photon detection element 7 adjacent to the fourth sub-depletion region 22. It may be created by The fourth sub-depletion region 22 can reduce or substantially prevent electrons or holes from moving to the third main depletion region 34 due to surface defects of the single-photon detection element 7.

The present disclosure can provide a single photon detection element 7 with small noise.

Figure 23 is a top view of the single photon detection device of Figure 22 according to an example embodiment.

Referring to FIG. 23, the single photon detection element 7 may have a circular shape. Specifically, the fourth contact area 222 may have a circular shape, and the third well 210 and the third contact area 214 may have a circular ring shape. The third well 210 and the third contact area 214 may surround the fourth contact area 222 . For example, the fourth contact area 222, the third well 210, and the third contact area 214 may have the same center. The third well 210 and the third contact area 214 may be sequentially arranged in a direction away from the fourth contact area 222 .

The single photon detection element 7 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3 to 8, the single photon detection element 7 may have a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an elliptical shape. You can.

Figure 24 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 22 may not be described.

Referring to Figure 24, a single photon detection element 8 may be provided. The single photon detection element 8 may comprise a single photon avalanche diode (SPAD). Unlike what is described with reference to FIG. 22, the single photon detection element 8 may further include a guard ring area 240.

A guard ring area 240 may be provided on the side of the fifth well 216. The guard ring area 240 can alleviate concentration of electric fields at the corners of the fifth well 216 and prevent pre-mature breakdown. The premature breakdown phenomenon occurs first at the corner of the fifth well 216 before a sufficiently large electric field is applied to the third main depletion region 34, and the electric field is concentrated at the corner of the fifth well 216. It occurs according to The guard ring area 240 can improve the breakdown characteristics of the single photon detection device 8. The guard ring area 240 may surround the fifth well 216. For example, the guard ring area 240 may have a ring shape extending along the side of the fifth well 216. The guard ring area 240 may directly contact the fifth well 216. The guard ring area 240 may be spaced apart from the third contact area 214 and the second relief area 212 . However, this is just an example. In another example, the guard ring area 240 may directly contact the third contact area 214 and the second relief area 212.

The third well 210 may extend to the area between the guard ring area 240 and the second relief area 212 and the area between the guard ring area 240 and the third contact area 214. For example, the area between the guard ring area 240 and the second relief area 212 and the area between the guard ring area 240 and the third contact area 214 may be filled with the third well 210. . The guard ring area 240 may have the same conductivity type as the fourth contact area 222 . The doping concentration of the guard ring region 240 may be lower than that of the fourth contact region 222. For example, the doping concentration of the guard ring region 240 may be about 1x10 ¹⁵ to 1x10 ¹⁸ cm ^-3 .

The present disclosure can provide a single photon detection device 8 with low noise and improved breakdown characteristics.

Figure 25 is a top view of the single photon detection device of Figure 24 according to an example embodiment.

Referring to FIG. 25, the single photon detection element 8 may have a circular shape. Specifically, the fourth contact area 222 may have a circular shape, and the guard ring area 240, the third well 210, and the third contact area 214 may have a circular ring shape. The guard ring region 240, the third well 210, and the third contact region 214 may surround the third depletion formation region 230. For example, the fourth contact area 222, the guard ring area 240, the third well 210, and the third contact area 214 may have the same center. The guard ring area 240, the third well 210, and the third contact area 214 may be sequentially arranged in a direction away from the fourth contact area 222.

The single photon detection element 8 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3-8, the single photon detection element 8 may have a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an oval shape. You can.

Figure 26 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 1 may not be described.

Referring to Figure 26, a single photon detection element 9 may be provided. The single photon detection element 9 may comprise a single photon avalanche diode (SPAD). The single photon detection element 9 may be substantially the same as the single photon detection element 1 described with reference to FIG. 1, except for the first well 110 and the second conductivity type region 101.

The doping concentration of the first well 110 may have a gradient. For example, the doping concentration in the first well 110 may be lower as the distance from the second depletion formation region 100 increases.

The second conductive region 101 may be provided on the first well 110 . Although the second conductive region 101 is shown as being provided between the first relaxation region 112 and the second well 120 and between the first contact region 114 and the second well 120, this is an example. It is an enemy. In another example, the second conductive region 101 is provided between the first contact region 114 and the second well 120 and is not provided between the first relaxation region 112 and the second well 120. It may not be possible.

The second conductivity type region 101 may have a second conductivity type. When the conductivity type of the first well 110 is n-type, the conductivity type of the second conductivity type region 101 may be p-type. When the conductivity type of the first well 110 is p-type, the conductivity type of the second conductivity type region 101 may be n-type. The second conductivity type region 101 may have substantially the same doping concentration as the second depletion formation region 100 .

Figure 27 is a top view of the single photon detection device of Figure 26 according to an example embodiment.

Referring to FIG. 27, the single photon detection element 9 may have a circular shape. Specifically, the first depletion formation region 130 may have a circular shape, and the second contact region 122, the second well 120, the first well 110, the second conductive region 101, And the first contact area 114 may have a circular ring shape. The second contact region 122, the second well 120, the first well 110, the second conductive region 101, and the first contact region 114 surround the first depletion formation region 130. It can be rice. For example, the first depletion formation region 130, the second contact region 122, the second well 120, the first well 110, the second conductive region 101, and the first contact region ( 114) may have the same center. The second contact region 122, the second well 120, the first well 110, the second conductive region 101, and the first contact region 114 are located away from the first depletion formation region 130. They can be arranged sequentially in one direction.

The single photon detection element 9 is shown as having a circular shape, but this is not limiting. In another example, as shown in FIGS. 3 to 8, the single photon detection element 9 has a square shape, an octagonal shape, a square shape with rounded corners, a rectangular shape, a rectangular shape with rounded corners, or an oval shape. You can have it.

Figure 28 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 22 may not be described.

Referring to FIG. 28, a single photon detection element 7-1 may be provided. The single photon detection element 7-1 may include a single photon avalanche diode (SPAD). The single photon detection element 7-1 is substantially similar to the single photon detection element 7 described with reference to FIG. 22, except that it includes a lower well 201 instead of the fourth depletion region (200 in FIG. 22). may be the same.

The lower well 201 may be provided below the third well 210. The lower well 201 may be provided on the opposite side of the fifth well 216 to the third well 210 . The lower well 201 may be regions formed by doping a semiconductor substrate (eg, a p-type or n-type silicon (Si) substrate). The lower well 201 may have the same conductivity type as the third well 210. The lower well 201 may have a first conductivity type. The lower well 201 may be doped at a higher concentration than the third well 210. For example, the doping concentration of the lower well 201 may be about 1x10 ¹⁵ to 1x10 ²¹ cm ^-3 .

The lower well 201 can reduce the size of the electric field generated below the single photon detection element 7-1. The smaller the size of the electric field generated at the bottom of the single-photon detection element 7-1, the more electrons or holes (hereinafter referred to as noise carriers) generated due to defects on the lower surface of the single-photon detection element 7-1. carriers) may have a low drift rate. The lower the drift speed of noise carriers, the smaller the influence of noise carriers on the single photon detection element 7-1 (for example, the extent to which noise carriers move to the third main depletion region 34). Accordingly, the single photon detection device 7-1 of the present disclosure may have small noise.

Figure 29 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 28 may not be described.

Referring to FIG. 29, a single photon detection element 7-2 may be provided. The single photon detection element 7-2 may include a single photon avalanche diode (SPAD). The single photon detection element 7-2 has the single photon detection element 7-2 described with reference to FIG. 28, except that it includes a third relaxation region 212a and a deeper fourth relaxation region 212b instead of the second relaxation region 212. It may be substantially the same as the photon detection element 7-1.

The third relief area 212a may be provided below the third contact area 214. The third relief area 212a may directly contact the third contact area 214. The third relaxation region 212a may have a first conductivity type. The doping concentration of the third relaxation region 212a may be lower than that of the first contact region 114 and may be higher than that of the first well 110 . For example, the doping concentration of the third relaxation region 212a may be about 1x10 ¹⁵ to 1x10 ¹⁹ cm ^-3 . In one example, the third relief area 212a may be substantially the same as the second relief area (212 in FIG. 28).

The fourth relief area 212b may be provided below the third relief area 212a. The fourth relief area 212b may contact the third relief area 212a. The fourth relaxation region 212b may have a first conductivity type. The fourth relaxation region 212b may have a doping concentration in a similar range to that of the third relaxation region 212a. For example, the doping concentration of the fourth relaxation region 212b may be about 1x10 ¹⁵ to 1x10 ¹⁹ cm ^-3 .

When the third relaxation area 212a and the fourth relaxation area 212b are used, a uniform bias voltage may be applied to the third well 210. When a plurality of single-photon detection elements 7-2 are disposed adjacent to each other, a space between adjacent single-photon detection elements 7-2 is formed by the third relaxation region 212a and the fourth relaxation region 212b. Crosstalk can be prevented.

Figure 30 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 24 may not be described.

Referring to FIG. 30, a single photon detection element 8-1 may be provided. The single photon detection element 8-1 may include a single photon avalanche diode (SPAD). The single photon detection element 8-1 is substantially similar to the single photon detection element 8 described with reference to FIG. 24, except that it includes a lower well 201 instead of the fourth depletion region (200 in FIG. 24). may be the same.

The lower well 201 may be provided below the third well 210. The lower well 201 may be provided on the opposite side of the fifth well 216 with respect to the third well 210 . The lower well 201 may be regions formed by doping a semiconductor substrate (eg, a p-type or n-type silicon (Si) substrate). The lower well 201 may have the same conductivity type as the third well 210. The lower well 201 may have a first conductivity type. The lower well 201 may be doped at a higher concentration than the third well 210. For example, the doping concentration of the lower well 201 may be about 1x10 ¹⁵ to 1x10 ²¹ cm ^-3 .

The lower well 201 can reduce the size of the electric field generated below the single photon detection element 8-1. The smaller the size of the electric field generated at the bottom of the single-photon detection element 8-1, the more electrons or holes (hereinafter referred to as noise carriers) generated due to defects on the lower surface of the single-photon detection element 8-1. carriers) may have a low drift rate. The lower the drift speed of noise carriers, the smaller the influence of noise carriers on the single photon detection element 8-1 (for example, the degree to which noise carriers move to the third main depletion region 34). Accordingly, the single photon detection device 8-1 of the present disclosure may have small noise.

Figure 31 is a cross-sectional view of a single photon detection device according to an example embodiment. For brevity of explanation, content substantially the same as that described with reference to FIG. 30 may not be described.

Referring to FIG. 31, a single photon detection element 8-2 may be provided. The single photon detection element 8-2 may include a single photon avalanche diode (SPAD). The single photon detection element 8-2 is the single photon detection element described with reference to FIG. 30, except that the single photon detection element 8-2 includes a relaxation region 212a and a deeper relaxation region 212b instead of the second relaxation region 212 ( It may be substantially the same as 8-1).

The third relief area 212a may be provided below the third contact area 214. The third relief area 212a may directly contact the third contact area 214. The third relaxation region 212a may have a first conductivity type. The doping concentration of the third relaxation region 212a may be lower than that of the first contact region 114 and may be higher than that of the first well 110 . For example, the doping concentration of the third relaxation region 212a may be about 1x10 ¹⁵ to 1x10 ¹⁹ cm ^-3 . In one example, the third relief area 212a may be substantially the same as the second relief area (212 in FIG. 30).

The fourth relief area 212b may be provided below the third relief area 212a. The fourth relief area 212b may contact the third relief area 212a. The fourth relaxation region 212b may have a first conductivity type. The fourth relaxation region 212b may have a doping concentration in a similar range to that of the third relaxation region 212a. For example, the doping concentration of the fourth relaxation region 212b may be about 1x10 ¹⁵ to 1x10 ¹⁹ cm ^-3 .

When the third relaxation area 212a and the fourth relaxation area 212b are used, a uniform bias voltage may be applied to the third well 210. When a plurality of single-photon detection elements 8-2 are disposed adjacent to each other, a space between adjacent single-photon detection elements 8-2 is formed by the third relaxation region 212a and the fourth relaxation region 212b. Crosstalk can be prevented.

Figure 32 is a block diagram for explaining an electronic device according to an example embodiment.

Referring to FIG. 32, an electronic device 4000 may be provided. The electronic device 4000 may irradiate light toward a subject (not shown) and detect light reflected by the subject and returning to the electronic device 4000. The electronic device 4000 may include a beam steering device 4010. The beam steering device 4010 can adjust the irradiation direction of light emitted to the outside of the electronic device 4000. Beam steering device 4010 may be a mechanical or non-mechanical (semiconductor) beam steering device. The electronic device 4000 may include a light source unit within the beam steering device 4010 or may include a light source unit provided separately from the beam steering device 4010. The beam steering device 4010 may be a scanning type light emitting device. However, the light emitting device of the electronic device 4000 is not limited to the beam steering device 4010. In another example, the electronic device 4000 may include a flash-type light emitting device instead of or together with the beam steering device 4010. A flash-type light emitting device can irradiate light to an area covering the entire field of view at once without a scanning process.

Light steered by the beam steering device 4010 may be reflected by the subject and return to the electronic device 4000. The electronic device 4000 may include a detection unit 4020 for detecting light reflected by a subject. The detection unit 4020 may include a plurality of light detection elements and may further include other optical members. The plurality of photodetection elements is one of the single photon detection elements (1, 2, 3, 4, 5, 6, 7, 7-1, 7-2, 8, 8-1, 8-2, 9) described above. It can include either one. Additionally, the electronic device 4000 may further include a circuit unit 4030 connected to at least one of the beam steering device 4010 and the detection unit 4020. The circuit unit 4030 may include a calculation unit that acquires and operates data, and may further include a driver and a control unit. Additionally, the circuit unit 4030 may further include a power supply unit and memory.

Although the electronic device 4000 includes a beam steering device 4010 and a detection unit 4020 in one device, the beam steering device 4010 and the detection unit 4020 are not provided as one device and are separate devices. It may be provided separately in the device. Additionally, the circuit unit 4030 may not be connected to the beam steering device 4010 or the detection unit 4020 by wire, but may be connected through wireless communication.

The electronic device 4000 according to the embodiment described above can be applied to various electronic devices. For example, the electronic device 4000 may be applied to a LiDAR (Light Detection And Ranging, LiDAR) device. The LiDAR device may be a phase-shift or time-of-flight (TOF) device. In addition, single photon detection elements (1, 2, 3, 4, 5, 6, 7, 7-1, 7-2, 8, 8-1, 8-2, 9) according to embodiments or electrons containing the same The device 4000 includes smartphones, wearable devices (glass-type devices implementing augmented reality and virtual reality, etc.), Internet of Things (IoT) devices, home appliance devices, tablet PCs (Personal Computers), and PDA (Personal Digital Assistants). , it can be installed in electronic devices such as portable multimedia players (PMP), navigation, drones, robots, unmanned cars, autonomous vehicles, and advanced driver assistance systems (ADAS).

Figures 33 and 34 are conceptual diagrams showing a case where a LiDAR device is applied to a vehicle according to an exemplary embodiment.

Referring to FIGS. 33 and 34 , the LiDAR device 5010 can be applied to the vehicle 5000 and information about the subject 6000 can be obtained using it. The vehicle 5000 may be a car with autonomous driving capabilities. The LiDAR device 5010 can detect an object or person, that is, a subject 6000, in the direction in which the vehicle 5000 travels. The LiDAR device 5010 can measure the distance to the subject 6000 using information such as the time difference between the transmission signal and the detection signal. The LiDAR device 5010 can obtain information about a close subject 6010 and a distant subject 6020 within the scanning range. The LiDAR device 5010 may include the electronic device 4000 described with reference to FIG. 32 .

Although the LiDAR device 5010 is disposed in front of the vehicle 5000 and detects the subject 6000 in the direction in which the vehicle 5000 travels, this is not limited. In another example, the LiDAR device 5010 may be placed at a plurality of locations on the vehicle 5000 so as to detect all subjects 6000 around the vehicle 5000. For example, four LiDAR devices 5010 may be disposed at the front, rear, and both sides of the vehicle 5000, respectively. In another example, the LiDAR device 5010 is placed on the roof of the vehicle 5000, rotates, and can detect all subjects 6000 around the vehicle 5000.

The above description of embodiments of the technical idea of the present disclosure provides examples for explaining the technical idea of the present disclosure. Therefore, the technical idea of the present disclosure is not limited to the above embodiments, and various modifications and changes can be made by combining the above embodiments by those skilled in the art within the technical idea of the present disclosure. This possibility is obvious.

1, 2, 3, 4, 5, 6, 7, 7-1, 7-2, 8, 8-1, 8-2, 9: Single photon detection element
SE1, SE2: Single photon detector SPA: Single photon detector array
10: first sub-depletion region 12: third sub-depletion region
20: second sub-depletion region 30, 32, 34: main depletion region
22: fourth sub-depletion region 100: second depletion formation region
110: first well 120: second well
130: first depletion formation region 100: second depletion formation region
114: first contact area 122: second contact area
112: first relief area 240, 500: guarding area
210: third well 220: fourth well
216: fifth well 230: third depletion formation region
200: fourth depletion formation region 214: third contact region 222: fourth contact region 212: second relaxation region 1000: light detection element 2000: control layer
2100: Wiring 2002: Insulating layer
2200: control layer 2202: circuit
3000: Lens portion 101: Second conductive region 201: Lower well 212a: Third relaxation region 212b: Fourth relaxation region 4000: Electronic device
5010: Lidar device

Claims (23)

a first well having a first conductivity type and receiving incident light incident from the outside;
a second well disposed on the first well in the direction in which the incident light travels and having a second conductivity type different from the first conductivity type;
a second depletion formation region provided on an opposite side of the second well with the first well interposed therebetween, spaced apart from the second well, and having the second conductivity type;
a main depletion region provided between the first well and the second well and configured to multiply electrons or holes generated by the incident light;
a second sub-depletion region provided between the second depletion formation region and the first well; and
A first contact region electrically connected to the first well and having the first conductivity type;
The second sub-depletion region and the main depletion region are arranged along the arrangement direction of the first well and the second well. According to claim 1,
It further includes a relief area provided between the first contact area and the first well,
the relaxation region has the first conductivity type,
A single photon detection device wherein the doping concentration of the relaxation region is lower than the doping concentration of the first contact region. According to claim 1,
It further includes a second conductive type region provided between the second well and the first contact region,
A single photon detection device wherein the second conductivity type region has the second conductivity type. According to claim 1,
The first contact region is provided on an opposite side of the second depletion formation region with the first well interposed therebetween. According to claim 1,
a first depletion formation region provided on the second well and having the first conductivity type; and
A single photon detection device further comprising a first sub-depletion region provided between the second well and the first depletion formation region. According to claim 5,
It further includes a second contact region electrically connected to the second well,
The second contact region has the second conductivity type,
A single photon detection device wherein the doping concentration of the second contact region is higher than the doping concentration of the second well. According to claim 1,
It further includes a guard ring area provided on a side of the second well,
The guard ring area is a single photon detection device having the second conductivity type. According to claim 7,
The guard ring area extends onto the bottom surface of the second well and overlaps the second well from a planar perspective. According to claim 1,
The first contact region surrounds the second well. According to claim 1,
The first well extends from the bottom of the second well to the side of the second well. According to claim 1,
It further includes a third well provided between the first well and the second sub-depletion region,
The third well is a single photon detection device having the first conductivity type. According to claim 11,
The third well is configured to surround the first well and the second well. According to claim 11,
A single photon detection device wherein the first well is electrically connected to the first contact region through the third well. According to claim 11,
A single photon detection device wherein the doping concentration of the third well is lower than the doping concentration of the first well. According to claim 11,
It further includes a guard ring region provided on a side of the second well and having the second conductivity type,
The guard ring area is in contact with the first well and the third well. A single-photon detection device that receives light and generates an electrical signal;
a control layer that processes the electrical signals; and
Includes a lens unit that receives the light from the outside and focuses it on the single photon detection element,
The single photon detection element includes a first well having a first conductivity type, a second well provided on an opposite side of the lens unit with the first well in between and having a second conductivity type different from the first conductivity type, and a second depletion formation region provided between the first well and the lens unit, spaced apart from the second well, and having the second conductivity type; a second depletion formation region provided between the first well and the second well and generated by incident light; or a main depletion region configured to multiply holes, a second sub-depletion region provided between the second depletion forming region and the first well, and a first conductivity type electrically connected to the first well. 1 Contains a contact area,
The second sub-depletion region and the main depletion region are arranged along the arrangement direction of the first well and the second well. According to claim 16,
The control layer is a single photon detector disposed between the single photon detection element and the lens unit. According to claim 16,
The single photon detection element is a single photon detector disposed between the control layer and the lens unit. According to claim 18,
The single photon detection element:
a first depletion formation region provided on the second well and having the first conductivity type; and
It further includes a first sub-depletion region provided between the second well and the first depletion formation region,
The first depletion formation region is disposed closer to the control layer than to the lens unit. According to claim 16,
The control layer is:
insulating layer;
wires; and
Circuits; including,
The wires electrically connect the first well and the second well and the circuits,
A single photon detector wherein the circuits include a quenching circuit and a readout circuit. According to claim 20,
A single photon detector wherein the circuits include a recharge circuit, a memory, an amplifier circuit, a counter, and a gate circuit. According to claim 16,
A single photon detector comprising at least one of a color filter, a bandpass filter, and an anti-reflection coating provided between the single photon detection element and the lens unit. A plurality of single photon detection elements that receive light and generate an electrical signal;
a control layer that processes the electrical signals; and
A plurality of lenses that receive the light from the outside and focus it on the plurality of single photon detection elements, respectively,
Each of the plurality of single photon detection elements includes a first well having a first conductivity type, a second conductivity type different from the first conductivity type provided on the opposite side of the plurality of lenses with the first well in between. A second well, a second depletion formation region provided between the first well and the plurality of lenses and spaced from the second well and having the second conductivity type, is provided between the first well and the second well. a main depletion region provided and configured to multiply electrons or holes generated by incident light, a second sub-depletion region provided between the second depletion forming region and the first well, and electrically connected to the first well; Includes a first contact region having the first conductivity type,
The second sub-depletion region and the main depletion region are arranged along the arrangement direction of the first well and the second well.

Images