JP2018032804A - Semiconductor device, optical print head, image formation apparatus, and manufacturing method of semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus capable of reducing the number of short circuits occurring and reducing a loss when taking out light generated by a three-terminal light emitting element, and a method for manufacturing the same. A semiconductor device 100 includes a light emitting thyristor 110 arranged on a first surface 101a of a substrate 101, and first to third terminals (anode electrode 120, cathode electrode 130, gate electrode 140) of the light emitting thyristor 110. ) Corresponding to the organic insulating film 107 that covers the light emitting thyristor 110, and the first to third terminals 120, 130, 140 connected to the first to third terminals 120, 130, 140 via the opening 107a, respectively. The three-terminal light emitting element 110 and the organic insulating film 107 have the wirings 121, 131, and 141 of 3, and are end faces 151 that are perpendicular to or sharply angled with respect to the first surface 101a, and are the three-terminal light emitting elements. It has a cut-out portion 150 including an end face 151 of a structure in which an organic insulating film 107 is laminated on 110. [Selection diagram] Fig. 1

Description

  The present invention relates to a semiconductor device having a plurality of three-terminal light emitting elements, an optical print head having the semiconductor device, an image forming apparatus having the optical print head, and a method for manufacturing the semiconductor device.

  An optical print head including a light emitting thyristor array (light emitting element array) including a plurality of light emitting thyristors (light emitting elements) has been proposed. Since the light-emitting thyristor is a three-terminal light-emitting element, the number of terminals of the light-emitting thyristor array, the number of electrodes connected to the terminals, and the number of wires connected to the electrodes are light-emitting diodes (LEDs) that are two-terminal light-emitting elements. More than in the case of arrays. For this reason, in the light-emitting thyristor array, the number of short-circuits at the intersection of the wiring and the electrode is larger than that in the LED array, and it is difficult to reduce the size of the device. In view of this, a light-emitting thyristor array, which is a semiconductor device that reduces the number of occurrences of short circuits and enables a reduction in device size, has been proposed (see, for example, Patent Document 1).

JP 2011-18837 A

  In the semiconductor device described above, an organic insulating film such as polyimide is used as an insulating film used for preventing a short circuit. Since the organic insulating film is a high refractive index material, the light incident from the light emitting thyristor on the organic insulating film substantially perpendicularly (light whose incident angle is a right angle or a narrow range close to a right angle) is The light passes through the organic insulating film and is used for exposure of the photosensitive drum. However, light other than light that is incident substantially perpendicular to the organic insulating film does not pass through the organic insulating film, travels through the organic insulating film as a waveguide, and leaks from a location away from the light emitting thyristor that emits light. Get out. Thus, in the semiconductor device, a loss occurs when light generated by the light emitting thyristor is extracted.

  An object of the present invention is to reduce the number of occurrences of a short circuit, reduce a loss when taking out light generated by a three-terminal light emitting element, a semiconductor device, an optical print head, an image forming apparatus, and It is to provide a method for manufacturing the semiconductor device.

  A semiconductor device according to one embodiment of the present invention is arranged in a predetermined direction over a first surface of a substrate, and is provided between a first terminal, a second terminal, and the first terminal and the second terminal. A plurality of three-terminal light-emitting elements each having a third terminal to which a signal for controlling conduction is input; and openings corresponding to the first to third terminals, covering the plurality of three-terminal light-emitting elements. An organic insulating film; and first to third wirings provided on the organic insulating film and connected to the first to third terminals through the openings, respectively. Each of the terminal light-emitting elements and the organic insulating film are end faces that are perpendicular or acute to the first surface, and the organic insulating film is laminated on each of the plurality of three-terminal light-emitting elements. It has the cut-off part containing the said end surface.

  An optical print head according to another aspect of the present invention includes the above-described semiconductor device.

  An image forming apparatus according to another aspect of the present invention includes the optical print head.

  According to still another aspect of the present invention, there is provided a method for manufacturing a semiconductor device, wherein a first terminal, a second terminal, and the first terminal and the second terminal are arranged in a predetermined direction on a first surface of a substrate. Forming a plurality of three-terminal light-emitting elements having a third terminal to which a signal for controlling conduction between the plurality of three-terminal light-emitting elements is input, and forming each of the plurality of three-terminal light-emitting elements on the first surface A step of forming a cut-off portion including an end face having a right angle or an acute angle, and an organic insulating film having openings corresponding to the first to third terminals and covering the plurality of three-terminal light-emitting elements. Forming, and forming first to third wirings provided on the organic insulating film and connected to the first to third terminals through the openings, respectively. It is a feature.

  According to the present invention, not only the light transmitted through the organic insulating film but also the light that travels through the organic insulating film and is extracted from the end face of the cut-off portion can be used, so that the light loss can be reduced. Further, according to the present invention, the number of short circuits can be reduced by using an organic insulating film.

It is a schematic plan view which shows the structure of the light emitting thyristor array (light emitting element array) as a semiconductor device concerning Embodiment 1 of this invention. It is a schematic sectional drawing which shows the cross-sectional structure which cuts the semiconductor device of FIG. 1 by S2-S2 line. It is a schematic sectional drawing which shows the cross-sectional structure which cuts the semiconductor device of FIG. 1 by S3-S3 line. (A) to (c) are schematic cross-sectional views showing the structure of a semiconductor thin film used for manufacturing the semiconductor device according to the first embodiment. (A) And (b) is a schematic sectional drawing which shows the manufacturing process of the cut-off part of the semiconductor device which concerns on Embodiment 1. FIG. It is a schematic plan view which shows the structure of the light emitting thyristor array (light emitting element array) as a semiconductor device concerning Embodiment 2 of this invention. It is a schematic sectional drawing which shows the cross-sectional structure which cuts the semiconductor device of FIG. 6 by the S7-S7 line. It is a schematic sectional drawing which shows the structure of the optical print head concerning Embodiment 3 of this invention. FIG. 9 is a schematic plan view showing the light emitting thyristor array unit shown in FIG. 8. It is a schematic sectional drawing which shows the structure of the image forming apparatus which concerns on Embodiment 4 of this invention.

  A semiconductor device, an optical print head, an image forming apparatus, and a method for manufacturing a semiconductor device according to embodiments of the present invention will be described below with reference to the drawings. In order to facilitate understanding of the relationship between the drawings, the drawings show coordinate axes of an xyz orthogonal coordinate system. The x axis is a coordinate axis indicating the arrangement direction (x direction) of a plurality of three-terminal light emitting elements arranged on the substrate, and the y axis is a coordinate axis in a direction parallel to the substrate and perpendicular to the x axis (y direction). is there. The z axis is a coordinate axis in the thickness direction (z direction) of the substrate orthogonal to both the x axis and the y axis.

<< 1 >> Embodiment 1
<< 1-1 >> Configuration FIG. 1 is a schematic plan view showing a structure of a light-emitting thyristor array (light-emitting element array) as a semiconductor device 100 according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view showing a cross-sectional structure of the semiconductor device 100 of FIG. 1 taken along the line S2-S2. FIG. 3 is a schematic cross-sectional view showing a cross-sectional structure of the semiconductor device 100 of FIG. 1 taken along line S3-S3. In FIG. 1, the passivation film 108 is not shown for easy understanding of the internal structure.

  As shown in FIGS. 1 to 3, the semiconductor device 100 according to the first embodiment includes a plurality of three-terminal light emitting elements arranged in a predetermined direction (x direction) on the first surface 101 a of the substrate 101. A plurality of light emitting thyristors 110 are provided. The plurality of light emitting thyristors 110 are arranged at regular intervals in the x direction (longitudinal direction of the substrate 101). The semiconductor device 100 can be bonded onto the first surface 101 a of the substrate 101. However, the planarization film 102 may be provided between the first surface 101 a of the substrate 101 and the light emitting thyristor 110. The planarization film 102 has a planarized flat surface (second surface) 102a as a surface to which the light emitting thyristor 110 is bonded. The flat surface 102a desirably has a surface roughness of 20 nm or less. When the planarizing film 102 is provided, the light emitting thyristor 110 is bonded onto the planar surface 102a of the planarizing film 102 by, for example, intermolecular force. Note that the number and arrangement of the light-emitting thyristors 110 are not limited to the examples shown in FIGS.

  2 and 3, the light-emitting thyristor 110 includes a first n-type semiconductor layer 103 as a first conductivity type semiconductor layer and a second n-type semiconductor layer 103 formed on the first n-type semiconductor layer 103. A first p-type semiconductor layer 104 as a first conductive type semiconductor layer; a second n-type semiconductor layer 105 as a first conductive type semiconductor layer formed on the first p-type semiconductor layer 104; And a second p-type semiconductor layer 106 as a second conductivity type semiconductor layer formed on the second n-type semiconductor layer 105. As a constituent material of each layer of the light emitting thyristor 110, for example, a GaAs semiconductor such as AlGaAs and GaAs is used. Note that the first conductivity type may be p-type and the second conductivity type may be n-type.

  The second p-type semiconductor layer 106 is a first terminal (p-type anode layer). The first n-type semiconductor layer 103 is a second terminal (n-type cathode layer). The second n-type semiconductor layer 105 is a third terminal (n-type gate layer) to which a signal (gate signal) for controlling conduction between the anode layer and the cathode layer is input. The semiconductor device 100 is electrically connected to the anode electrode 120 electrically connected to the second p-type semiconductor layer 106 (first terminal) and to the first n-type semiconductor layer 103 (second terminal). And the gate electrode 140 electrically connected to the second n-type semiconductor layer 105 (third terminal). Further, the semiconductor device 100 includes an organic insulating film 107 such as polyimide that covers the light emitting thyristor 110. The organic insulating film 107 has an opening 107a on the first terminal (p-type anode layer), the second terminal (n-type cathode layer), and the third terminal (n-type gate layer). The organic insulating film 107 is desirably substantially transparent. In the example of FIG. 1, the organic insulating film 107 has an opening 107 a on the anode electrode 120, the cathode electrode 130, and the gate electrode 140.

  Further, the semiconductor device 100 includes an anode lead-out wiring 121 as a wiring layer connected to the anode electrode 120 through the opening 107a and a cathode lead-out wiring as a wiring layer connected to the cathode electrode 130 through the opening 107a. 131 and a gate lead-out wiring 141 as a wiring layer connected to the gate electrode 140 through the opening 107a.

  The light-emitting thyristor 110 and the organic insulating film 107 are end surfaces 151 that are perpendicular or acute to the first surface 101 a of the substrate 101, and the organic insulating film 107 is stacked on the light-emitting thyristor 110. A cut-away portion 150 including an end surface 151 is provided. The end surface 151 of the cut-off portion 150 of the substrate 101 is a surface formed by wet etching, for example. In FIG. 2, the end surface 151 of the cut-off portion 150 includes a part of the planarizing film 102 (upper part in the thickness direction), the light emitting thyristor 110 (first n-type semiconductor layer 103 in FIG. 2), and organic It is a surface of a structure in which an insulating film 107 is stacked.

  The semiconductor device 100 further includes a passivation film 108 that covers the organic insulating film 107 and a plurality of wiring layers (the anode lead line 121, the cathode lead line 131, and the gate lead line 141).

  In FIG. 1, the anode lead-out wiring 121 connected to the anode electrode 120 is a wiring layer extending in the y direction, and is connected to the anode pad 123 via the anode common wiring 122. In other words, the anode common wiring 122 is connected to the anode pad 123 for controlling the anode voltage of the four light emitting thyristors 110 arranged in the x direction.

  The gate lead-out wiring 141 connected to the gate electrode 140 is a wiring layer extending in the y direction, and is connected to the gate pad 143 through the gate common wiring 142. In other words, the gate common wiring 142 is connected to the gate electrode 140 on the second n-type semiconductor layer 105 by the gate lead-out wiring 141, and any one of the four gate pads 143 formed on the substrate 101. Connected to

  The cathode lead-out wiring 131 connected to the cathode electrode 130 is a wiring layer extending in the y direction, and is connected to the cathode pad 133 via the cathode common wiring 132. In other words, the cathode common wiring 132 is connected by the cathode electrode 130 on the first n-type semiconductor layer 103 and the cathode lead-out wiring 131, and further controls one cathode voltage formed on the substrate 101. The cathode pad 133 is connected.

  Note that intersections (other than connection points) between the lead-out wiring (the anode lead-out wiring 121, the cathode lead-out wiring 131, and the gate lead-out wiring 141) and the common wiring (the anode common wiring 122, the cathode common wiring 132, and the gate common wiring 142). The organic insulating film 107 is also formed between the lead-out wiring and the common wiring at the intersection).

<< 1-2 >> Manufacturing Method FIGS. 4A to 4C are schematic cross-sectional views illustrating the structure of the semiconductor thin film 111 used for manufacturing the semiconductor device 100 according to the first embodiment. When the semiconductor thin film 111 is manufactured, as shown in FIG. 4A, a buffer layer 161, a sacrificial layer 162, a first n-type semiconductor layer 103a, a first layer are formed on a base substrate 160 for manufacturing a semiconductor thin film. A p-type semiconductor layer 104a, a second n-type semiconductor layer 105a, and a second p-type semiconductor layer 106a are formed in this order. These layers are formed by, for example, epitaxial growth and impurity implantation.

  The buffer layer 161 is a layer for forming a semiconductor layer formed thereon. The sacrificial layer 162 is a layer that is etched when the semiconductor thin film 111 is peeled from the base material substrate 160. The first n-type semiconductor layer 103a, the first p-type semiconductor layer 104a, the second n-type semiconductor layer 105a, and the second p-type semiconductor layer 106a, which are semiconductor layers on the sacrificial layer 162, are shown in FIG. 3 corresponds to the first n-type semiconductor layer 103, the first p-type semiconductor layer 104, the second n-type semiconductor layer 105, and the second p-type semiconductor layer 106 of the light-emitting thyristor 110 shown in FIG. The sacrificial layer 162 is a layer whose wet etching etching rate is faster than the wet etching etching rate of the semiconductor thin film 111.

  When the semiconductor thin film 111 is peeled from the base material substrate 160, as shown in FIG. 4B, the sacrificial layer is formed using an etchant having an etching rate of the semiconductor thin film 111 higher than that of the sacrificial layer 162. 162 is selectively wet-etched. FIG. 4B shows the state of the semiconductor thin film 111 during the etching. For example, AlAs is used as the sacrificial layer 162, a GaAs-based material is used as the semiconductor thin film 111, and the sacrificial layer 162 may be removed by hot etching.

  The peeled semiconductor thin film 111 is carried from the base material substrate 160 onto the flat surface 102a of the flattening film 102 on the substrate 101 by a holding device (not shown), and as shown in FIG. Pressurized on 102a and bonded by intermolecular force.

  5A and 5B are schematic cross-sectional views illustrating the manufacturing process of the cut-off portion 150 of the semiconductor device 100 according to the first embodiment. The semiconductor thin film 111 shown in FIG. 4C is formed by using a photolithography technique and an etching technique, as shown in FIG. 5A, the first n-type semiconductor layer 103 and the second n-type semiconductor layer. 105, the second p-type semiconductor layer 106 is processed into a mesa shape as a surface.

  Next, as shown in FIG. 5B, the region other than the region where the anode common wire 122, the cathode common wire 132, the gate common wire 142, the anode lead wire 121, the cathode lead wire 131, and the gate lead wire 141 are formed. In the region, the light-emitting thyristor 110 and a part of the planarization film 102 are etched to form a structure having a cut-off portion 150 including an end surface 151. The end surface 151 is formed at a right angle or an acute angle with respect to the surface 101 a of the substrate 101.

  Next, the cathode electrode 130 is formed on the first n-type semiconductor layer 103, the gate electrode 140 is formed on the second n-type semiconductor layer 105, and the anode electrode 120 is formed on the second p-type semiconductor layer 106 by vapor deposition or sputtering. Then, the common cathode wiring 132, the common gate wiring 142, and the common anode wiring 122 are formed.

  Next, the anode lead wire 121, the gate lead wire 141, and the cathode lead wire are connected so as to connect the anode electrode 120 and the anode pad 123, the gate electrode 140 and the gate pad 143, and the cathode electrode 130 and the cathode pad 133 by vapor deposition or sputtering. 131 is formed.

  Prior to the formation of the anode lead-out wiring 121, the gate lead-out wiring 141, and the cathode lead-out wiring 131, the organic insulating film 107 is formed so that the wiring does not come in contact except at the connection portion. The organic insulating film 107 is formed of polyimide resin, epoxy resin, acrylic resin, or the like. The organic insulating film 107 is formed by coating a resin by spin coating or spray coating, and then patterning by photolithography or the like. As the organic insulating film 107, it is desirable to use a material having high light transmittance.

  After forming the anode lead-out wiring 121, the gate lead-out wiring 141, and the cathode lead-out wiring 131, the light emitting thyristor 110, the anode electrode 120, the gate electrode 140, the cathode electrode 130, the anode lead-out wiring 121, the gate lead-out wiring 141, the cathode lead-out wiring 131, and the anode The passivation film 108 is formed using an organic insulating film or an inorganic insulating film so that the common wiring 122, the gate common wiring 142, and the cathode common wiring 132 are not short-circuited.

  When the organic insulating film 107 and the passivation film 108 are formed, the organic insulating film 107 and the passivation film 108 are formed by using the light emitting thyristor 110, the anode electrode 120, the gate electrode 140, the cathode electrode 130, the anode lead wiring 121, the gate lead wiring 141, and the cathode. By forming only in the vicinity of the lead-out wiring 131, the anode common wiring 122, the gate common wiring 142, and the cathode common wiring 132, the end surface 151 of the cut-off portion 150 is formed as shown in FIG. The light-emitting thyristor 110 and the organic insulating film 107 have a cross-sectional structure including an end face 151 on which the organic insulating film 107 is stacked. The end surface 151 is formed to have a right angle or an acute angle (that is, 90 degrees or less) with respect to the first surface 101 a of the substrate 101. With this configuration, the light emitted from the end surface 151 proceeds at least in the upward direction (+ x direction) or obliquely upward direction of the substrate 101, so that the light emitted from the end surface 151 can be used.

  The process of forming the cut-off portion 150 before forming the organic insulating film 107 and then forming the organic insulating film 107 has been described. However, after forming the organic insulating film 107, etching is performed to form the cut-out portion 150. It is also possible to form.

<< 1-3 >> Operation The cathode electrode 130 is electrically connected to the first n-type semiconductor layer 103 of the light-emitting thyristor 110, and the cathode pad 133 is connected to the ground and has a ground potential. . Therefore, the light-emitting thyristor 110 is driven by ON / OFF of the voltage of the anode electrode 120 and ON / OFF of the voltage of the gate electrode 140.

  When the light emitting thyristor 110 is not caused to emit light, the anode electrode 120 is set to the ground potential. At this time, since no current flows from the anode electrode 120 to the cathode electrode 130, the light emitting thyristor 110 does not emit light.

  When the light emitting thyristor 110 is caused to emit light, a voltage is applied to the anode electrode 120 (turned on), and the potential of the gate electrode 140 is set to the ground potential. At this time, since a potential difference is generated, a current flows from the anode electrode 120 to the cathode electrode 130, and the light emitting thyristor 110 emits light.

  When stopping the light emission of the light emitting thyristor 110 that emits light, the anode electrode 120 is set to the ground potential and the gate electrode 140 is set to the predetermined potential, so that the current from the anode electrode 120 to the cathode electrode 130 does not flow, and the light emission is performed. The thyristor 110 stops emitting light.

<< 1-4 >> Effect As described above, in the semiconductor device 100 according to the first embodiment, since the cut-out portion 150 having the end surface 151 is provided in the vicinity (near the light emitting thyristor 110), the organic insulating film The light that could not pass through 107 is not easily transmitted to a distant place by the semiconductor thin film 111 or the organic insulating film 107 and is emitted from the end face 151 of the cut-off portion 150. As described above, in the first embodiment, the light that could not pass through the organic insulating film 107 is emitted from the vicinity of the light emitting thyristor that is emitted, and thus is used as light in the exposure process, for example. Therefore, it is difficult to lose the light by propagating the light emission of the light emitting thyristor 110, and the light extraction efficiency is improved.

  In Embodiment 1, since the organic insulating film 107 and the light emitting thyristor 110 are separated by the cut-off portion 150, light leakage at a position far from the light emitting thyristor that emits light can be reduced. .

  In addition, since the cut-out portions 150 are formed under substantially the same conditions around each light-emitting thyristor of the 100 light-emitting thyristors, the influence of waveguide on the light emission of each light-emitting thyristor becomes substantially uniform. The light-emitting thyristors at both ends (both ends in the x direction) of the light-emitting thyristors can be prevented from inconveniences such that the amount of light emission becomes non-uniform due to the influence of the waveguide.

  Furthermore, in the first embodiment, as shown in FIG. 2, the light emitting thyristor 110 is divided by the cut-away portion 150, so that the stress acting in the longitudinal direction (x direction) of the substrate 101 can be relaxed. .

<< 2 >> Embodiment 2
<< 2-1 >> Configuration FIG. 6 is a schematic plan view showing a structure of a light-emitting thyristor array (light-emitting element array) as a semiconductor device 200 according to Embodiment 2 of the present invention. In FIG. 6, the same reference numerals as those shown in FIG. 1 are given to the same or corresponding elements as those shown in FIG. The semiconductor device 200 according to the second embodiment includes a cut-out portion (first cut-off portion) in three directions (one place in the + x direction, one place in the −x direction, and one place in the + y direction) around the anode electrode 120. ) 210 and a cut-away portion (second cut-away portion) 220. The first cut-away portion 210 has an end surface 211 provided in the + x direction of the anode electrode 120 and an end surface 211 provided in the −x direction. The second cut-away portion 220 has an end face 221 provided in the + y direction of the anode electrode 120. Further, the first cut-out portion 210 and the second cut-out portion 220 have a structure including a part of the surface of the planarizing film 102 and end faces 211 and 221 formed by etching the light-emitting thyristor 110 to be cut up. Yes. In FIG. 6, the passivation film 108 is not shown for easy understanding of the internal structure.

  FIG. 7 is a schematic cross-sectional view showing a cross-sectional structure of the semiconductor device 200 of FIG. 6 taken along line S7-S7. In FIG. 7, the same reference numerals as those shown in FIG. 1 are given to the same or corresponding elements as those shown in FIG. 6 is the same as the structure shown in FIG. 3 (Embodiment 1). As shown in FIGS. 6 and 7, in the second embodiment, the first cut-out portion 210 and the second cut-out portion 220 include at least the first terminal (the p-type anode in FIGS. 6 and 7). It is formed at a position adjacent to the layer 106). Other than the above, the semiconductor device 200 according to the second embodiment is the same as the semiconductor device 100 according to the first embodiment.

<< 2-2 >> Operation The operation of causing the semiconductor device 200 according to the second embodiment to emit light and the operation of stopping the light emission are the same as those of the semiconductor device 100 according to the first embodiment.

<< 2-3 >> Effect As described above, according to the semiconductor device 200 according to the second embodiment, in addition to the same effect as the effect in the semiconductor device 100 according to the first embodiment, the first cut-off portion. Since 210 and the second cut-out portion 220 have cut-out portions in the three directions of the light-emitting thyristor 110, the loss of light emission can be further reduced.

<< 3 >> Embodiment 3
<< 3-1 >> Configuration FIG. 8 is a schematic cross-sectional view showing the structure of an optical print head 300 according to Embodiment 3 of the present invention. The optical print head 300 is an exposure apparatus of an electrophotographic printer as an electrophotographic image forming apparatus. As shown in FIG. 8, the optical print head 300 includes a base member 301, a mounting substrate 310 as a COB (Chip On Board) substrate, and a light emitting thyristor array chip 303 (for example, as shown in FIG. 1). And a lens array 304 including a plurality of erecting equal-magnification imaging lenses, a lens holder 305, and a clamper 306. The mounting substrate 310 and the light emitting thyristor array chip 303 constitute a light emitting thyristor array unit 311. The base member 301 is a member for fixing the mounting substrate 310, and an opening 302 for fixing the mounting substrate 310 and the lens holder 305 to the base member 301 using a clamper 306 is provided on a side surface of the base member 301. Is provided. The lens holder 305 is formed, for example, by injection molding an organic polymer material or the like. The mounting substrate 310 is a unit in which the light emitting thyristor array chip 303 is integrated on the substrate. The light-emitting thyristor array chip 303 includes a light-emitting thyristor array (a plurality of light-emitting thyristors bonded together) on a substrate having a drive circuit. The lens array 304 is an optical lens group that forms an image of light emitted from the light-emitting thyristor array (light-emitting element array) of the light-emitting thyristor array chip 303 on a photosensitive drum as an image carrier. The lens holder 305 holds the lens array 304 at a predetermined position on the base member 301. The clamper 306 is a spring member that sandwiches and holds each component through the opening 302 of the base member 301 and the opening of the lens holder 305.

  FIG. 9 is a schematic plan view showing the light-emitting thyristor array unit 311 shown in FIG. As shown in FIGS. 8 and 9, a light emitting thyristor array unit 311 is mounted on the base member 301. The light-emitting thyristor array unit 311 is obtained by mounting a light-emitting thyristor array chip 303 including any one of the semiconductor devices 100 and 200 according to the first and second embodiments on a mounting substrate 310. As shown in FIGS. 8 and 9, a plurality of semiconductor devices 100 and 200 according to the first and second embodiments are arranged as light emitting thyristor array chips 303 along the longitudinal direction on the mounting substrate 310. Yes. Electronic components that drive and control the semiconductor devices 100 and 200 are arranged on the mounting substrate 310, and control signals and power are supplied from the outside for the electronic component mounting, wiring 312 and connection areas 312 and 313, and the like. For this purpose, a connector 314 and the like are provided.

  In the third embodiment, the light emitting element array of the optical print head 300 is one of the semiconductor devices 100 and 200 of the first and second embodiments.

  In the optical print head 300, a light emitting thyristor array selectively emits light according to print data, and the light is imaged on a photosensitive drum uniformly charged by a lens array 304. As a result, an electrostatic latent image is formed on the photosensitive drum, and then an image made of a developer is formed (printed) on the print medium (paper) through a development process, a transfer process, and a fixing process.

  As described above, according to the optical print head 300 according to the third embodiment, one of the semiconductor devices 100 and 200 according to the first and second embodiments is used as the light-emitting thyristor array unit 311. An optical print head with high light extraction efficiency can be provided.

  Further, according to the optical print head 300 according to the third embodiment, since any one of the semiconductor devices 100 and 200 according to the first and second embodiments is used as the light-emitting thyristor array unit 311, the occurrence of a short circuit is suppressed. can do.

<3-2> Operation The light-emitting thyristor array selectively emits light by the drive circuit, and the light is imaged on the photosensitive drum by the lens. As a result, an image is formed on the photosensitive drum.

<< 3-3 >> Effect As described above, the optical print head 300 according to the third embodiment uses a chip including the light-emitting thyristor according to the first or second embodiment. For this reason, the light extraction efficiency can be improved, and light is not transmitted to a region far from the light emitting thyristor, so that the printing quality can be improved.

<< 4 >> Embodiment 4
<< 4-1 >> Configuration FIG. 10 is a cross-sectional view schematically showing a configuration of an image forming apparatus 400 according to Embodiment 4 of the present invention. The image forming apparatus 400 is, for example, a color printer that employs an electrophotographic system. The image forming apparatus 400 includes the optical print heads described in the third embodiment as optical print heads 411K, 411Y, 411M, and 411C that are exposure apparatuses.

  As shown in FIG. 10, the image forming apparatus 400 has image forming units 410 </ b> K, 410 </ b> Y, 410 </ b> M, which form developer images (toner images) on a recording medium P such as paper by electrophotographic method as a main configuration. 410C, the medium supply unit 420 that supplies the recording medium P to the image forming units 410K, 410Y, 410M, and 410C, the transport unit 430 that transports the recording medium P, and the image forming units 410K, 410Y, 410M, and 410C. A transfer roller 440 serving as a transfer unit arranged correspondingly, a fixing unit 450 that fixes the toner image transferred onto the recording medium P, and a medium discharge that discharges the recording medium P that has passed through the fixing unit 450 to the outside. A paper discharge roller pair 425 as a unit. Note that the number of image forming units included in the image forming apparatus 400 may be 3 or less, or 5 or more. Further, the present invention can be applied to a monochrome printer having one image forming unit as long as it is an apparatus that forms an image on a recording medium by an electrophotographic method. Furthermore, the present invention can be applied to other apparatuses such as a copying machine, a facsimile apparatus, and a multi-function peripheral apparatus (MFP) as long as the apparatus forms an image on a recording medium by an electrophotographic method.

  As shown in FIG. 10, the medium supply unit 420 includes a paper cassette 421, a hopping roller 422 that feeds the recording media P stacked in the paper cassette 421 one by one, and a recording medium P that is fed out from the paper cassette 421. And a roller pair 424 that conveys the recording medium P.

  The image forming units 410K, 410Y, 410M, and 410C are black (K) toner images, yellow (Y) toner images, magenta (M) toner images, and cyan (C) colors on the recording medium P. Each toner image is formed. The image forming units 410K, 410Y, 410M, and 410C are arranged along the medium conveyance path from the upstream side to the downstream side in the medium conveyance direction (arrow direction). The image forming units 410K, 410Y, 410M, and 410C have image forming units 412K, 412Y, 412M, and 412C for respective colors that are detachably formed. The image forming units 412K, 412Y, 412M, and 412C arranged in series are provided corresponding to the respective colors of the image forming units 410K, 410Y, 410M, and 410C. The image forming unit 412C forms an image with cyan toner, The image forming unit 412M forms an image with magenta toner, the image forming unit 412Y forms an image with yellow toner, and the image forming unit 412K forms an image with black toner. The image forming units 412K, 412Y, 412M, and 412C basically have the same structure except that the toner colors are different.

  The image forming units 410K, 410Y, 410M, and 410C have optical print heads 411K, 411Y, 411M, and 411C as exposure apparatuses for the respective colors.

  Each of the image forming units 412K, 412Y, 412M, and 412C includes a photosensitive drum 413 as an image carrier that is rotatably supported, and a charging roller 414 as a charging member that uniformly charges the surface of the photosensitive drum 413. After forming an electrostatic latent image on the surface of the photosensitive drum 413 by exposure with the optical print heads 411K, 411Y, 411M, and 411C, the toner is supplied to the surface of the photosensitive drum 413 to cope with the electrostatic latent image. And a developing device 415 that forms a toner image.

  The developing device 415 includes a toner accommodating portion as a developer accommodating portion that forms a developer accommodating space for accommodating toner, a developing roller 416 as a developer carrying member that supplies toner to the surface of the photosensitive drum 413, and a toner. A supply roller 417 that supplies toner accommodated in the accommodation portion to the developing roller 416 and a developing blade 418 as a toner regulating member that regulates the thickness of the toner layer on the surface of the developing roller 416 are provided.

  Exposure by each of the optical print heads 411K, 411Y, 411M, and 411C is executed based on image data for printing on the surface of the uniformly charged photosensitive drum 413. Each of the optical print heads 411K, 411Y, 411M, and 411C includes a light emitting element array in which light emitting thyristors are arranged as a plurality of light emitting elements in the axial direction of the photosensitive drum 413.

  As shown in FIG. 10, the transport unit 430 includes a transport belt (transfer belt) 433 that electrostatically attracts and transports the recording medium P, a drive roller 431 that is driven by the drive unit to drive the transport belt 433, and A tension roller (driven roller) 432 that stretches the conveying belt 433 in a pair with the driving roller 431 is provided.

  As shown in FIG. 10, the transfer roller 440 is disposed so as to face the respective photosensitive drums 413 of the image forming units 412K, 412Y, 412M, and 412C with the conveyance belt 433 interposed therebetween. The developer image (toner image) formed on the surface of the photosensitive drum 413 of each of the image forming units 412K, 412Y, 412M, and 412C by the transfer roller 440 is transported in the direction of the arrow along the medium transport path. A color image in which a plurality of toner images are superimposed is formed by sequentially transferring the image onto the upper surface of the medium P.

  The fixing device 450 includes a pair of rollers 451 and 452 that are in pressure contact with each other. The roller 451 is a heat roller with a built-in heater, and the roller 452 is a pressure roller pressed against the roller 451. The recording medium P having an unfixed developer image (toner image) passes between a pair of rollers 451 and 452 of the fixing device 450. At this time, the unfixed toner image is fixed on the recording medium P by being heated and pressurized.

<< 4-2 >> Operation First, the recording medium P in the paper cassette 421 is fed out by the hopping roller 422 and sent to the registration roller 423. Subsequently, the recording medium P is sent from the registration rollers 423 to the conveying belt 433 via the roller pair 24, and is conveyed to the image forming units 412K, 412Y, 412M, and 412C as the conveying belt 433 travels. In the image forming units 412K, 412Y, 412M, and 412C, the surface of the photosensitive drum 413 is charged by the charging roller 414 and exposed by the optical print heads 411K, 411Y, 411M, and 411C to form an electrostatic latent image. To the electrostatic latent image, the toner thinned on the developing roller 416 is electrostatically attached to form a toner image of each color. The color toner images are transferred to the recording medium P by the transfer roller 440, and a color toner image is formed on the recording medium P. After the transfer, the toner remaining on the photosensitive drum 413 is removed by a cleaning device (not shown). The sheet on which the color toner image is formed is sent to the fixing device 450. In the fixing device 450, the color toner image is fixed on the recording medium P, and a color image is formed. The recording medium P on which the toner image is formed is discharged to a paper stacker by a discharge roller pair 425.

<< 4-3 >> Effect As described above, in the image forming apparatus 400 according to the fourth embodiment, the optical print head described in the third embodiment is replaced with the optical print heads 411K, 411Y, and 411M that are exposure apparatuses. , 411C. For this reason, the light extraction efficiency can be improved, and light is not transmitted to a region far from the light emitting thyristor, so that the printing quality can be improved.

<< 5 >> Modifications In the first and second embodiments, an example in which the substrate 101 is an n-type GaAs substrate and the semiconductor thin film 111 (light-emitting thyristor 110) is stacked thereon has been described. The substrate 101 is a p-type GaAs substrate. A semiconductor thin film may be laminated thereon. In this case, on the substrate 101, a first p-type semiconductor layer (p-type anode layer), a first n-type semiconductor layer (n-type gate layer), and a second p-type semiconductor layer (p-type gate). Layer) and a second n-type cathode layer (n-type cathode layer) are laminated in this order. When a light emitting thyristor is stacked on an n-type GaAS substrate, it is a p-gate thyristor. However, when a light-emitting thyristor is stacked on a p-type GaAs substrate, it is an n-gate thyristor.

  100, 200 Semiconductor device, 101 substrate, 101a main surface (first surface), 110 light emitting thyristor (3-terminal light emitting element), 102 planarizing film, 102a flat surface (second surface), 103 n-type cathode layer ( First n-type semiconductor layer, second terminal), 103a first n-type semiconductor layer, 104 p-type gate layer (first p-type semiconductor layer), 104a first p-type semiconductor layer, 105 n-type Gate layer (second n-type semiconductor layer, third terminal), 105a second n-type semiconductor layer, 106 p-type anode layer (second p-type semiconductor layer, first terminal), 106a second p-type semiconductor layer, 107 organic insulating film, 107a opening, 108 passivation, 120 anode electrode, 121 anode lead-out wiring, 122 anode common wiring, 123 anode Pad, 130 Cathode electrode, 131 Cathode lead wire, 132 Cathode common wire, 133 Cathode pad, 140 Gate electrode, 141 Gate lead wire, 142 Gate common wire, 143 Gate pad, 150 Cut-off portion, 151 End face, 160 Base material substrate 161 buffer layer, 162 sacrificial layer, 300 optical print head, 301 base member, 302 opening, 303 light emitting thyristor array chip, 304 lens array, 305 lens holder, 306 clamper, 310 mounting substrate, 400 image forming apparatus, 411K, 411Y, 411M, 411C Optical print head, 410K, 410Y, 410M, 410C Image forming unit.

Claims (13)

A third terminal that is arranged in a predetermined direction on the first surface of the substrate and that inputs a first terminal, a second terminal, and a signal for controlling conduction between the first terminal and the second terminal. A plurality of three-terminal light emitting devices having the following terminals:
An organic insulating film having openings corresponding to the first to third terminals and covering the plurality of three-terminal light-emitting elements;
First to third wirings provided on the organic insulating film and connected to the first to third terminals through the openings;
Have
Each of the plurality of three-terminal light-emitting elements and the organic insulating film are end surfaces having a right angle or an acute angle with respect to the first surface, and the organic insulating film is formed on each of the plurality of three-terminal light-emitting elements. A semiconductor device comprising a cut-away portion including the end face of a stacked structure.   2. The semiconductor device according to claim 1, wherein the cut-away portion includes the end face in the predetermined direction of each of the plurality of three-terminal light emitting elements. The cut-off portion is
Each of the plurality of three-terminal light emitting elements includes a first cut-out portion including a first end surface that is the end surface in the predetermined direction;
Provided on a second end surface of the structure that is perpendicular or acute to the first surface, intersects the first end surface, and has the organic insulating film laminated on each of the plurality of three-terminal light emitting elements. A second cut-off portion formed,
The semiconductor device according to claim 1, comprising:   4. The semiconductor device according to claim 1, wherein the cut-off portion is formed at least at a position adjacent to the first terminal. 5. The three-terminal light emitting element is a light emitting thyristor;
The first terminal is an anode layer;
The second terminal is a cathode layer;
The semiconductor device according to claim 1, wherein the third terminal is a gate layer. The three-terminal light emitting element is a light emitting thyristor;
The first terminal is a cathode layer;
The second terminal is an anode layer;
The semiconductor device according to claim 1, wherein the third terminal is a gate layer. A planarizing film having a flat second surface and provided on the first surface;
A semiconductor film including a plurality of stacked semiconductor layers and bonded on the second surface;
Have
The semiconductor device according to any one of claims 1 to 6, wherein the three-terminal light emitting element is a light emitting thyristor formed in the semiconductor film. The end face of the cut-off portion is a side surface having a structure in which the three-terminal light-emitting element is laminated on the planarizing film and the organic insulating film is laminated on the three-terminal light-emitting element. Item 8. The semiconductor device according to Item 7.   The semiconductor device according to claim 1, further comprising a passivation film that covers the organic insulating film and the plurality of wirings.   An optical print head comprising the semiconductor device according to claim 1.   An image forming apparatus comprising the optical print head according to claim 10. A first terminal, a second terminal, and a signal for controlling conduction between the first terminal and the second terminal are input on the first surface of the substrate in a predetermined direction. Forming a plurality of three-terminal light-emitting elements having three terminals;
Forming each of the plurality of three-terminal light-emitting elements having a cut-off portion including an end surface that is perpendicular or acute to the first surface;
Forming an organic insulating film having openings corresponding to the first to third terminals and covering the plurality of three-terminal light emitting elements;
Forming first to third wirings provided on the organic insulating film and connected to the first to third terminals through the openings;
A method for manufacturing a semiconductor device, comprising:   The method of manufacturing a semiconductor device according to claim 12, wherein the step of forming the cut-off portion is a step of etching a part of the plurality of three-terminal light emitting elements.

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