KR102485400B1 - Apparatus for processing substrate - Google Patents

Abstract

The apparatus of the present invention includes a process chamber defining a process space; a gas injection unit installed in the process chamber; a plasma power supply including at least one RF power supply to apply at least one RF power to the gas dispensing part, which is a first plasma electrode, to form a plasma atmosphere into the process chamber; an impedance matching unit connected between the plasma power supply unit and the gas dispensing unit for impedance matching between the at least one RF power source and the process chamber; a chuck structure including a second plasma electrode installed in the process chamber to face the gas spraying part, which is the first plasma electrode; and a second plasma connected between a grounding unit and the second plasma electrode to control an impedance on a path from the second plasma electrode to the grounding unit in order to control a plasma atmosphere between the gas dispensing unit and the chuck structure. and regulating circuitry configured to control the RF current flowing to the electrodes.

Description

Substrate processing apparatus {Apparatus for processing substrate}

The present invention relates to semiconductor manufacturing, and more particularly, to a substrate processing apparatus using plasma.

In the manufacture of semiconductor devices, a process using plasma is applied. For example, a process such as deposition or etching may be performed at a high speed even at a low process temperature by activating a process gas using plasma. In a substrate processing apparatus using such a plasma, control of a plasma environment, such as control of plasma matching according to a process chamber and control of process variables such as gas amount and pressure, is important.

However, in the case of conventional plasma control, the plasma environment in the process chamber can be stabilized by performing impedance matching according to the conditions of the process chamber, but since the process chamber is grounded as a whole, it is difficult to optimize the current flowing on the substrate. There were limits. In particular, in a substrate processing apparatus to which a chuck structure is applied, it is necessary to precisely control a plasma environment on a substrate considering electrostatic force.

An object of the present invention is to solve various problems including the above problems, and to provide a substrate processing apparatus capable of controlling process conditions by controlling a plasma environment on a substrate. However, these tasks are illustrative, and the scope of the present invention is not limited thereby.

A substrate processing apparatus according to one aspect of the present invention for solving the above problems includes a process chamber defining a processing space for processing a thin film therein; a gas injection unit installed in the process chamber and supplying a process gas to the process space; a plasma power supply including at least one RF power supply to apply at least one RF power to the gas dispensing part, which is a first plasma electrode, to form a plasma atmosphere into the process chamber; an impedance matching unit connected between the plasma power supply unit and the gas dispensing unit for impedance matching between the at least one RF power source and the process chamber; It is configured to include a second plasma electrode installed in the process chamber facing the gas spraying part, which is the first plasma electrode, wherein the second plasma electrode has a first electrode part disposed in a first region and spaced apart from the first region. a chuck structure including a second electrode unit disposed in a second region; And to control the plasma atmosphere between the gas ejection part and the chuck structure, doedoe connected between the ground part and the second plasma electrode, to adjust the impedance on the path from the second plasma electrode to the ground part. A control circuit unit configured to control an RF current flowing to the plasma electrode; wherein the control circuit unit is connected between a ground unit and the first electrode unit to determine a first impedance on a path from the first electrode unit to the ground unit. A variably regulating first current regulating circuit part and a grounding part, connected between the grounding part and the second electrode part, and variably adjusting a second impedance on a path from the second electrode part to the grounding part. Equipped with a circuit part.

In the substrate processing apparatus, the first area may be a center area of the chuck structure, and the second area may be an edge area surrounding the center area.

In the substrate processing apparatus, the first current control circuit unit and the second current control circuit unit at least one RF filter for passing at least one RF current generated by the at least one RF power source and flowing through the chuck structure Each includes, but the RF filter may include at least one variable capacitor configured to variably adjust the impedance of the RF filter.

In the substrate processing apparatus, the control circuit unit determines the capacitance value of the variable capacitor corresponding to the target stress of the thin film by using lookup table data for a relationship between the capacitance value of the variable capacitor and the stress data of the thin film. A current control circuit unit and a control unit capable of setting each of the second current control circuit units may be further provided.

In the substrate processing apparatus, the control circuit unit sets the capacitance value of the variable capacitor corresponding to the target deposition rate of the thin film using lookup table data for a relationship between the capacitance value of the variable capacitor and the deposition rate data of the thin film. A current control circuit unit and a control unit capable of setting each of the second current control circuit units may be further included.

In the substrate processing apparatus, the control circuit unit of the variable capacitor corresponding to the target map uniformity of the thin film using lookup table data for the relationship between the capacitance value of the variable capacitor and the map uniformity data of the thin film. A control unit configured to set capacitance values for each of the first current control circuit unit and the second current control circuit unit may be further included.

In the substrate processing apparatus, the first current control circuit unit and the second current control circuit unit at least one RF filter for passing at least one RF current generated by the at least one RF power source and flowing through the chuck structure Wherein the at least one RF power source includes a first RF power source of a first frequency band and a second RF power source of a second frequency band greater than the first frequency band to provide a dual RF power source, wherein the RF The filter includes at least a first RF filter for passing a first RF current generated by the first RF power supply and flowing through the chuck structure, and a first RF filter generated by at least the second RF power supply to pass the first RF current flowing through the chuck structure. It may include a second RF filter for passing a second RF current of a second frequency band flowing through.

In the substrate processing apparatus, the first frequency band may have a frequency range of 300 kHz to 600 kHz, and the second frequency band may have a frequency range of 13.56 MHz to 27.12 MHz.

In the substrate processing apparatus, the first RF filter includes a first inductor and a first capacitor connected in parallel with each other, and the second RF filter includes a second inductor and a second capacitor connected in series with each other, At least one of the first capacitor and the second capacitor may be a variable capacitor configured to variably adjust the impedance of the RF filter.

In the substrate processing apparatus, the first RF filter may further include a third capacitor connected in series between a parallel connection structure of the first inductor and the first capacitor and a ground.

In the substrate processing apparatus, the first electrode unit and the second electrode unit may be electrostatic electrodes for applying electrostatic force to the substrate seated on the chuck structure.

The substrate processing apparatus further includes a constant power power supply unit including a DC power source to supply DC power to the electrostatic electrode, but the control circuit unit includes at least one DC current drawn from the constant power power supply unit for blocking. A DC blocking element may be further provided.

In the substrate processing apparatus, the chuck structure further includes a heater for heating the substrate, and a heater power supply unit connected to the heater to apply AC power to the heater; and a third RF filter connected between the heater power supply unit and the heater. may further include.

According to some embodiments of the present invention made as described above, it is possible to provide a substrate processing apparatus capable of improving RF transmission efficiency, tuning the thickness and stress of a thin film, and controlling a wafer map. Of course, the scope of the present invention is not limited by these effects.

1 is a diagram schematically showing a substrate processing apparatus according to an embodiment of the present invention.
FIG. 2 is a diagram schematically illustrating a flow of RF current when plasma power is applied in the substrate processing apparatus of FIG. 1 .
FIG. 3 is a diagram schematically showing an example of a configuration of a control circuit unit in the substrate processing apparatus of FIG. 1 .
FIG. 4 is a diagram schematically illustrating a process of adjusting a variable capacitor using some configurations of a control circuit unit of the substrate processing apparatus of FIG. 1 .
5 is a view schematically showing a substrate processing apparatus according to a modified embodiment of the present invention.

Throughout the specification, when referring to an element such as a film, region, or substrate being located “on” another element, the one element directly contacts “on” the other element, or It can be interpreted that there may be other components interposed therebetween. On the other hand, when an element is referred to as being located “directly on” another element, it is interpreted that there are no other elements intervening therebetween.

Embodiments of the present invention are described with reference to drawings that schematically show idealized embodiments of the present invention. In the drawings, variations of the depicted shape may be expected, depending on, for example, manufacturing techniques and/or tolerances. Therefore, embodiments of the inventive concept should not be construed as being limited to the specific shape of the region shown in this specification, but should include, for example, a change in shape caused by manufacturing. In addition, the thickness or size of each layer in the drawings may be exaggerated for convenience and clarity of explanation. Like symbols refer to like elements.

1 is a diagram schematically showing a substrate processing apparatus 100 according to an embodiment of the present invention.

Referring to FIG. 1 , a substrate processing apparatus 100 may include a process chamber 110 , a gas ejection unit 120 , and a chuck structure 130 .

The process chamber 110 may define a processing space 112 for processing (depositing or etching) a thin film therein. For example, the process chamber 110 is configured to be airtight and may be connected to a vacuum chamber (not shown) through an exhaust port to discharge process gases from the process space 112 and adjust the degree of vacuum within the process space 112. can The process chamber 110 may be provided in various shapes, and may include, for example, a sidewall portion defining the processing space 112 and a cover portion positioned on top of the sidewall portion.

The gas injection unit 120 may be installed in the process chamber 110 to supply process gas supplied from the outside of the process chamber 110 to the process space 112 . The gas spraying unit 120 may be installed in an upper part of the process chamber 110 to face the chuck structure 130 so as to spray process gas to the substrate S seated on the chuck structure 130 . The gas dispensing unit 120 includes at least one inlet hole formed on the upper side or side to receive process gas from the outside, and a plurality of inlet holes formed downward facing the substrate S to inject process gas onto the substrate S. It may include injection holes of.

For example, the gas spraying unit 120 may have various shapes such as a shower head shape and a nozzle shape. When the gas dispensing unit 120 is in the form of a shower head, the gas dispensing unit 120 may be coupled to the process chamber 110 in a form covering an upper portion of the process chamber 110 . For example, the gas dispensing unit 120 may be coupled to the side wall portion of the process chamber 110 in the form of a cover.

The chuck structure 130 is installed in the process chamber 110 to face the gas injection unit 120, and a substrate S may be seated thereon. The shape of the chuck structure 130 generally corresponds to the shape of the substrate (S), but is not limited thereto and may be provided in various shapes larger than the substrate (S) so that the substrate (S) can be stably seated thereon. In one example, the chuck structure 130 may be connected to an external motor (not shown) to enable elevation, and in this case, a bellows pipe (not shown) may be connected to maintain airtightness. Furthermore, since the chuck structure 130 is configured to place the substrate S thereon, it may also be called a substrate seat, a substrate support, or a susceptor. The chuck structure 130 may include a heater 137 for heating the substrate S.

The chuck structure 130 may include a first electrode part 135a disposed in a first area and a second electrode part 135b disposed in a second area spaced apart from the first area. In one embodiment of the present invention, the first area may be a center area of the chuck structure 130, and the second area may be an edge area surrounding the center area. However, the first area and the second area may be transformed into various distributions and shapes under the premise that they are spaced apart from each other. For example, the first area and the second area may be left and right areas of the chuck structure 130 , respectively. The first region and the second region may be upper and lower regions of the chuck structure 130 , respectively.

In one embodiment of the present invention, the first electrode unit 135a and the second electrode unit 135b may be electrostatic electrodes for applying electrostatic force to the substrate S seated on the chuck structure 130 . In another embodiment of the present invention, the first electrode portion 135a and the second electrode portion 135b may be understood as ground electrodes. It can be understood that two ground lines are spaced apart from each other in that the first electrode part 135a and the second electrode part 135b spaced apart from each other are connected to the ground.

Meanwhile, FIG. 1 is illustrated assuming a case in which two electrode units are spaced apart from each other, but this is exemplary and the scope of the present invention is not limited thereto. For example, the chuck structure 130 may include three or more electrode units spaced apart from each other.

The substrate processing apparatus 100 may further include a plasma power supply 140 and an impedance matching unit 146 .

The plasma power supply 140 may include at least one RF power source to apply at least one radio frequency (RF) power to the process chamber 110 to form a plasma atmosphere inside the process chamber 110 . For example, the plasma power supply 140 may be connected to apply RF power to the gas dispensing unit 120 . In this case, the gas injection unit 120 may also be called a power supply electrode, an upper electrode, or a first plasma electrode.

Meanwhile, in a configuration in which the plasma power supply 140 applies at least one RF power to the gas dispensing unit 120 to form a plasma atmosphere into the process chamber, the gas dispensing unit 120 may be understood as a first plasma electrode. In this case, the first electrode part 135a and the second electrode part 135b can be understood as a second plasma electrode installed to face the first plasma electrode.

The impedance matching unit 146 may be disposed between the plasma power supply 140 and the gas dispensing unit 120 for impedance matching between the RF power source and the process chamber 110 .

The number of RF power sources in the plasma power supply unit 140 may be one or plural. For example, the RF power source may include a first RF power source 142 of a first frequency band and a second RF power source 144 of a second frequency band higher than the first frequency band in order to control the plasma environment according to process conditions. can The dual frequency power supply composed of the first RF power supply 142 and the second RF power supply 144 has the advantage of being able to precisely control the process because the frequency band can be varied according to process conditions or process steps. Although FIG. 1 shows that the power of the plasma power supply 140 is two RF power sources 142 and 144, this is exemplary and the scope of the present invention is not limited thereto.

In one example of such a plasma power supply 140, the first RF power supply 142 is a low frequency (LF) power supply in which the first frequency band includes at least 470 kHz, and the second RF power supply 144 is 2 The frequency band may be a high frequency (HF) power supply including at least 27.12 MHz. The high frequency (HF) power supply may be an RF power supply in the frequency range of 5 MHz to 60 MHz, optionally 13.56 MHz to 27.12 MHz. The low frequency (LF) power supply may be an RF power supply in the frequency range of 100 kHz to 5 MHz, optionally 300 kHz to 600 kHz. In one embodiment, the second frequency band may have a frequency range of 13.56 MHz to 27.12 MHz, and the first frequency band may have a frequency range of 300 kHz to 600 kHz.

The RF power supplied from the plasma power supply 140 must be properly impedance matched between the plasma power supply 140 and the process chamber 110 through the impedance matching unit 146 so that it is not reflected from the process chamber 110 and returned. It can be effectively transferred to the process chamber 110 without In general, since the impedance of the plasma power supply 140 is fixed and the impedance of the process chamber 110 is not constant, the impedance matching unit matches the impedance of the process chamber 110 and the impedance of the plasma power supply 140. The impedance of 146 may be determined, but the scope of the present invention is not limited thereto.

For example, the impedance matching unit 146 may include a series or parallel combination of two or more selected from the group of a resistor R, an inductor L, and a capacitor C. Furthermore, the impedance matching unit 146 may adopt a variable capacitor or capacitor array switching structure so that its impedance value can be varied according to the frequency of RF power and process conditions.

The control circuit unit 160 is in contact with the second plasma electrode including the first electrode unit 135a and the second electrode unit 135b to control the plasma atmosphere between the gas dispensing unit 120 and the chuck structure 130. Branches can be linked. The control circuit unit 160 controls the RF current on the sidewall of the process chamber 110 on the premise that impedance matching is performed between the plasma power supply unit 140 and the process chamber 110 by the impedance matching unit 146. , To control the plasma characteristics on the substrate (S) by controlling the ratio of the RF current on the chuck structure 130 or the substrate (S), impedance matching between the plasma power supply 140 and the process chamber 110 It can be distinguished from the impedance matching unit 146 for In addition, as a comparative example, when RF power is applied to the chuck structure 130 instead of the gas ejection unit 120, a lower portion is provided between the chuck structure 130 and a lower RF power source (not shown) for impedance matching between the two. Since the impedance matching unit is added, the lower impedance matching unit and the control circuit unit 160 can also be distinguished.

The control circuit unit 160 is connected between the ground unit and the first electrode unit 135a to variably adjust a first impedance on a path from the first electrode unit 135a to the ground unit. ) and the ground portion, and connected between the ground portion and the second electrode portion 135b to variably adjust the second impedance on the path from the second electrode portion 135b to the ground portion (160b) can be provided.

As described above, since the plurality of electrode parts spaced apart from each other are connected to the ground, the control circuit is connected to each of the plurality of ground lines, and each control circuit optimizes the impedance of each ground line. can understand that In this case, the control circuit unit may be understood as an Impedance Matching System (IMS).

According to the technical idea of the present invention, RF transmission efficiency can be improved through impedance optimization of each of two or more ground lines, and process results (thickness of a thin film, stress) is possible, and wafer map control is possible through varying the impedance of each of two or more ground lines.

FIG. 2 is a diagram schematically illustrating a flow of RF current when plasma power is applied in the substrate processing apparatus of FIG. 1 .

Referring to FIG. 2 , when RF power is supplied from the plasma power supply unit 140 to the gas dispensing unit 120, the RF power is supplied to the process chamber 110 via the impedance matching unit 146, and the plasma power supply unit 140 The RF current It flows from the gas dispensing unit 120 . The RF current It flows to the chuck structure 130 via the plasma in the process chamber 120 and the RF current Iw flowing to the wall surface of the process chamber 110 via the plasma in the process chamber 110. It can be branched into RF current (Ic).

Since the substrate S is seated on the chuck structure 130, plasma properties, For example, it is necessary to control plasma density, uniformity, shape, and the like. To this end, it is necessary to control the ratio of the RF current Iw flowing through the wall surface of the process chamber 110 and the RF current Ic flowing through the chuck structure 130 . Since the sum of the two RF currents Iw and Ic is constant as the RF current It, it is necessary to adjust the impedance on the path from the chuck structure 130 to the ground in order to adjust the RF current Ic, and the control circuit unit ( 160a and 160b may control the RF current Ic flowing through the chuck structure 130 by adjusting the impedance on the path from the chuck structure 130 to the ground. Specifically, the first current control circuit unit 160a controls the RF current flowing through the first electrode unit 135a by adjusting the impedance on the path from the first electrode unit 135a of the chuck structure 130 to the ground unit. The second current control circuit unit 160b controls the RF current flowing to the second electrode unit 135b by adjusting the impedance on the path from the second electrode unit 135b of the chuck structure 130 to the ground unit. can do.

For example, if the RF current Iw flowing through the wall of the process chamber 110 becomes excessively large, plasma is dispersed to the periphery of the substrate S, resulting in poor plasma uniformity, resulting in poor uniformity of the deposited film on the substrate S. The uniformity of the etching film may deteriorate. However, if the RF current Ic is increased by increasing the plasma density on the chuck structure 130 or the substrate S through the control circuit units 160a and 160b, the uniformity of the deposited film and the uniformity of the etched film may be increased. Accordingly, plasma characteristics on the chuck structure 130 or the substrate S may be controlled by controlling the control circuit units 160a and 160b.

FIG. 3 is a diagram schematically showing an example of a configuration of a control circuit unit in the substrate processing apparatus of FIG. 1 .

Referring to FIG. 3 , the control circuit unit 160 may include RF filters 164 and 166 . When the power source in the plasma power supply unit 140 includes the first RF power source 142 and the second RF power source 144, the RF filter is configured to pass the first RF current I1 of at least a first frequency band. It may include a first RF filter 164 and a second RF filter 166 for passing a second RF current I2 of at least a second frequency band. Since the RF current may include the RF current of the harmonic component in addition to the RF current of the first frequency band and the second frequency band, the first RF filter 164 or the second RF filter 166 may include the RF current of the first frequency band and the second frequency band. It is necessary to pass the RF current of these harmonic components outside the second frequency band.

The first RF filter 164 may include at least a first inductor L1 and a first capacitor C1 connected in parallel with each other. Furthermore, the first RF filter 164 may further include a third capacitor C3 connected in series between the parallel connection structure of the first inductor L1 and the first capacitor C1 and the ground.

In the first RF filter 164, the RF current I11 lower than the second frequency band HF flows to the ground through the first inductor L1, and RF of higher harmonic components than the second frequency band HF The current I12 may flow to the ground through the first capacitor C1 and the third capacitor C3.

The second RF filter 166 may include a second inductor L2 and a second capacitor C2 connected in series with each other. For example, the second inductor L2 may be connected to the nodes n1 and n2, and the second capacitor C2 may be connected in series between the second inductor L2 and the ground. The second RF filter 166 may be configured to pass the second RF current I2 of the second frequency band HF.

Therefore, according to the above-described embodiment, a dual RF filter structure is configured in the control circuit unit 160 to correspond to the dual RF power sources of the high frequency power source and the low frequency power source, so that process characteristics can be more precisely controlled.

FIG. 4 is a diagram schematically illustrating a process of adjusting a variable capacitor using some configurations of a control circuit unit of the substrate processing apparatus of FIG. 1 .

Referring to FIGS. 3 and 4 together, in one embodiment of the present invention, the second capacitor C2 may be provided as a variable capacitor to adjust the impedance of the second RF filter 166 . In an additional embodiment, a sensor 165 for detecting the amount of the second RF current I2 flowing to the second RF filter 166 may be further added to the control circuitry 160 . In this case, the second RF current I2 is detected using the sensor 165, and the capacitance of the second capacitor C2 is adjusted so that the second RF current I2 becomes a desired value based on the detected value. may be

Furthermore, after the deposition or etching process is completed, film properties on the substrate S, such as stress, deposition rate, map uniformity, etc. are measured, and the capacitance of the second capacitor C2 is measured to obtain desired film properties according to the measurement results. can also be adjusted.

As described above, the second capacitor C2 may be a variable capacitance so that the impedance of the second RF filter 166 can be variably adjusted. When a variable capacitor is used, unlike the case where the capacitor C2 has a fixed value, it is easy to secure capacitance resolution and fine process control is possible, so it is possible to flexibly cope with process changes.

The control circuit unit 160 includes a sensor 165 for detecting the amount of the second RF current flowing through the second RF filter 166 or the magnitude of the voltage applied to the second RF filter 166, and detection by the sensor 165. A controller 161 capable of setting the value of the variable capacitance C2 through the input/output terminal 163 based on the values V and I may be further provided. The control unit 161 may set the value of the variable capacitor C2 by using LOOKUP TABLE data based on the value detected by the sensor 165 so as to respond to changes in the process state.

Illustratively, the process of changing the variable capacitance may include detecting the amount of the second RF current flowing from the sensor 165 to the second RF filter 166 or the magnitude of the voltage applied to the second RF filter 166. (S10), providing the value detected by the sensor 165 to the control unit 161; Matching a condition that can correspond to a change in process state using lookup table data based on the value detected by the sensor 165 (S30); and changing the value of the variable capacitor C2 corresponding to the matched condition (S40).

Reflecting the above information, the control unit 161 of various embodiments may be provided.

For example, the control unit 161 determines the capacitance value of the variable capacitor C2 corresponding to the target stress of the thin film using lookup table data for the relationship between the capacitance value of the variable capacitor C2 and the stress data of the thin film. may be set in real time for each of the first current control circuit unit 160a and the second current control circuit unit 160b.

As another example, the controller 161 determines the capacitance value of the variable capacitor C2 corresponding to the target deposition rate of the thin film using lookup table data for the relationship between the capacitance value of the variable capacitor C2 and the deposition rate data of the thin film. may be set in real time for each of the first current control circuit unit 160a and the second current control circuit unit 160b.

As another example, the control unit 161 determines the target map uniformity of the thin film using lookup table data for the relationship between the capacitance value of the variable capacitor C2 and the map uniformity data of the thin film. The corresponding capacitance value of the variable capacitor C2 may be set in real time for each of the first current control circuit unit 160a and the second current control circuit unit 160b.

As another example, the control unit 161 determines the target stress of the thin film by using lookup table data for the relationship between the capacitance value of the variable capacitor C2 and the stress, deposition rate, and map uniformity data of the thin film. , the capacitance value of the variable capacitor C2 corresponding to the deposition rate and map uniformity may be set in real time for each of the first current control circuit unit 160a and the second current control circuit unit 160b.

Meanwhile, in a modified example, the above-described real-time control method using the variable capacitor, sensor, and controller may be applied to the first RF filter 164 . In this case, the variable capacitor may be the first capacitor C1 constituting the first RF filter 164, and the sensor may determine the amount of the first RF current flowing to the first RF filter 164 or the first RF filter The magnitude of the voltage applied to 164 can be detected, and the controller can set the value of the variable capacitance C1 in real time based on the values V and I detected by the sensor. The configuration in which the control unit sets the value of the variable capacitance C1 using lookup table data is replaced with the above-described configuration.

5 is a view schematically showing a substrate processing apparatus according to a modified embodiment of the present invention.

Unlike FIG. 1 , the substrate processing apparatus 100 disclosed in FIG. 5 may further include a constant power power supply unit 150 . The chuck structure 130 may include an electrostatic electrode 135 composed of a first electrode part 135a and a second electrode part 135b in order to apply electrostatic force to the substrate S and fix it thereon. The constant power power supply 150 may include a DC power source 152 to supply DC power to the electrostatic electrode 135 . For example, the DC power source 152 may be installed so that one end thereof is connected to the ground and the other end is electrically connected to the electrostatic electrode 135 via the nodes n1 and n2.

Additionally, when the constant power power supply 150 and the control circuit 160 share nodes n1 and n2 and are connected to the electrostatic electrode 135 in parallel, the constant power power supply 150 is the electrostatic electrode A DC filter 155 disposed between the electrostatic electrode 135 and the DC power supply 152 may be included to block RF current through 135 from entering the DC power supply 152 . For example, DC filter 155 may be connected in series between nodes n1 and n2 and DC power supply 152 . Optionally, a resistor may be added between DC filter 155 and nodes n1 and n2. The DC filter 155 may be configured in various forms to pass DC current while blocking RF current.

Meanwhile, the control circuit unit 160 may be connected in parallel with the constant power power supply unit 150 between the electrostatic electrode 135 and the ground. For example, the control circuit unit 160 and the constant power supply unit 150 may be connected to each other at nodes n1 and n2 and electrically connected to the electrostatic electrode 135 . When connected in a shared structure in this way, the wiring structure connected to the electrostatic electrode 135 can be simplified, and thus the volume of the electrostatic electrode 135 can be reduced.

In this parallel connection structure, the RF current generated by the RF power supplies 142 and 144 and flowing through the electrostatic electrode 135 is passed through the control circuit unit 160 and is passed from the constant power power supply unit 150 to the node n1, The DC current flowing into the control circuit unit 160 through n2) needs to be blocked. To this end, the control circuit unit 160 may include at least one RF filter for passing RF current and at least one DC blocking element for blocking DC current. The DC blocking element may be provided separately from the RF filter, or may include some elements within the RF filter.

For example, referring to FIG. 3 , the control circuit unit 160 may include RF filters 164 and 166 and a DC blocking element 168 . When the first RF filter 164 passes the RF current of the first frequency band (low frequency, LF), the DC blocking element 168 blocks the DC current from flowing to the first RF filter 164. Node n1 , n2) and the first RF filter 164 may be connected in series. When the second RF filter 166 is configured to pass the RF current of the second frequency band (high frequency, HF) and block the low frequency band, the second RF filter 166 can block the DC current, so that the second RF filter 166, the connection of the DC blocking element can be omitted. In this case, it can also be interpreted that the second RF filter 166 has a DC blocking element.

For example, the first RF filter 164 includes a band rejection filter (BRF) that passes the first RF current I1 of the first frequency band (low frequency, LF) and the harmonic component, and The 2 RF filter 166 may include a band pass filter (BPF) that blocks DC current while passing the second RF current I2 of the second frequency band (high frequency, HF). Such a band reject filter (BRF) may be called a notch filter in that it rejects only a specific band and passes all other components. For example, the first RF filter may be configured as a band reject filter that rejects a second frequency band (HF) and passes the rest. Meanwhile, the first RF filter 164 may be called a dual band pass filter in that it passes a frequency band lower than the second frequency band (HF) and a band higher than the second frequency band (HF).

Meanwhile, the chuck structure 130 may include a heater 137 for heating the substrate S. The heater power supply unit 180 may be connected to the heater 137 to apply AC power to the heater 137 . Furthermore, the third RF filter 185 may be connected between the heater power supply unit 180 and the heater 137 to perform an impedance matching function between AC power of the heater power supply unit 180 and the heater 137 .

As described above, in the above-described embodiments, by controlling the plasma atmosphere or plasma characteristics on the chuck structure 130 or on the substrate S through the control circuit unit 160, process efficiency (eg, deposition rate, etching rate) is increased or Process uniformity (eg, deposition uniformity, etching uniformity) can be improved. In addition, the wiring structure of the stage of the chuck structure 130 is simplified by connecting the constant power power supply unit 150 and the control circuit unit 160 in parallel at the nodes n1 and n2 and connecting them to the electrostatic electrode 135 with a single wire. While doing so, it is possible to configure a circuit so that the RF current and the DC current do not interfere with each other.

So far, a substrate processing apparatus reflecting the technical idea of the present invention has been described. According to the substrate processing apparatus of the present invention providing an impedance matching system for two or more multi-mesh heaters, compared to a substrate processing apparatus providing an impedance matching system for one mesh heater, i) two or more grounds RF transmission efficiency can be improved through impedance optimization of each ground line, and ii) process results (thickness and stress) can be tuned through impedance variation of each of two or more ground lines. and iii) Wafer Map Control is possible by varying the impedance of each of two or more ground lines.

In each impedance matching system connected to multiple ground lines, the location of the maximum current flow is found through a split test of the capacitance value of the variable capacitor. The deposition rate may be maximized at the point where the RF transfer efficiency is maximized. Accordingly, RF transfer efficiency may be improved through impedance optimization of each of two or more ground lines.

Tuning to a desired process region is possible by increasing or decreasing the capacitance value of the variable capacitor in each of the impedance matching systems connected to the multiple ground lines. For example, when reducing the thickness of the thin film and increasing the stress, both the variable capacitance value of the first current control circuit 160a and the variable capacitance value of the second current control circuit 160b are increased, or the second current The variable capacitance value of the first current control circuit part 160a is increased while the variable capacitance value of the control circuit part 160b is maintained, or the variable capacitance value of the first current control circuit part 160a is maintained while the variable capacitance value of the first current control circuit part 160a is maintained. A variable capacitance value of the current control circuit unit 160b may be increased. Conversely, when the thickness of the thin film is increased and the stress is reduced, both the variable capacitance value of the first current control circuit unit 160a and the variable capacitance value of the second current control circuit unit 160b are reduced, or the second current control circuit unit 160b is used. The variable capacitance value of the first current regulating circuit 160a is reduced while the variable capacitance value of the circuit 160b is maintained, or the second current regulating circuit 160a is maintained while the variable capacitance value is maintained. The variable capacitance value of the control circuit unit 160b may be reduced. Accordingly, it is possible to tune process results (thickness and stress of a thin film) by varying the impedance of each of the two or more ground lines.

Tuning to a desired wafer map is possible by increasing or decreasing the capacitance value of the variable capacitor in each of the impedance matching systems connected to the multiple ground lines. For example, when it is desired to increase the thickness of the thin film at the center of the wafer and reduce the thickness of the thin film at the edge, or to decrease the stress of the thin film at the center of the wafer and increase the stress at the edge, the variable capacitance value of the first current control circuit 160a is reduced. and increase the variable capacitance value of the second current control circuit unit 160b. Alternatively, the variable capacitance value of the first current control circuit unit 160a may be reduced while maintaining the variable capacitance value of the second current control circuit unit 160b. Alternatively, the variable capacitance value of the second current control circuit unit 160b may be increased while maintaining the variable capacitance value of the first current control circuit unit 160a. In addition, for another example, when it is desired to decrease the thin film thickness of the wafer center portion and increase the thin film thickness of the edge portion, or to increase the thin film thickness of the wafer center portion and decrease the thin film stress of the edge portion, the variable capacitance of the first current control circuit unit 160a It is possible to increase the value and decrease the variable capacitance value of the second current control circuit unit 160b. Alternatively, the variable capacitance value of the first current control circuit unit 160a may be increased while maintaining the variable capacitance value of the second current control circuit unit 160b. Alternatively, the variable capacitance value of the second current control circuit unit 160b may be reduced while maintaining the variable capacitance value of the first current control circuit unit 160a.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims (13)

A process chamber defining a processing space for processing a thin film therein;
a gas injection unit installed in the process chamber and supplying a process gas to the process space;
a plasma power supply including at least one RF power supply to apply at least one RF power to the gas dispensing part, which is a first plasma electrode, to form a plasma atmosphere into the process chamber;
an impedance matching unit connected between the plasma power supply unit and the gas dispensing unit for impedance matching between the at least one RF power source and the process chamber;
It is configured to include a second plasma electrode installed in the process chamber facing the gas spraying part that is the first plasma electrode, wherein the second plasma electrode has a first electrode part disposed in a first region and a first region a chuck structure having a second electrode part disposed in a spaced apart second region; and
In order to control the plasma atmosphere between the gas ejection part and the chuck structure, the second plasma is connected between the ground part and the second plasma electrode to adjust an impedance on a path from the second plasma electrode to the ground part. Adjustment circuitry configured to control the RF current flowing to the electrodes;
The control circuit unit includes a first current control circuit unit connected between the ground unit and the first electrode unit and variably adjusting a first impedance on a path from the first electrode unit to the ground unit; A second current control circuit unit connected between the electrode units and variably adjusting a second impedance on a path from the second electrode unit to the ground unit,
The first current regulating circuit part and the second current regulating circuit part each include at least one RF filter for passing at least one RF current generated by the at least one RF power source and flowing through the chuck structure,
The RF filter includes at least one variable capacitor configured to variably adjust an impedance of the RF filter,
The adjusting circuit unit determines the capacitance value of the variable capacitor corresponding to the target stress of the thin film using lookup table data for a relationship between the capacitance value of the variable capacitor and the stress data of the thin film, and the first current adjusting circuit unit and the first current adjusting circuit unit. 2 further comprising a control unit that can be set for each current control circuit unit,
Substrate processing device. According to claim 1,
The first region is a center region of the chuck structure, and the second region is an edge region surrounding the center region.
Substrate processing device. delete delete A process chamber defining a processing space for processing a thin film therein;
a gas injection unit installed in the process chamber and supplying a process gas to the process space;
a plasma power supply including at least one RF power supply to apply at least one RF power to the gas dispensing part, which is a first plasma electrode, to form a plasma atmosphere into the process chamber;
an impedance matching unit connected between the plasma power supply unit and the gas dispensing unit for impedance matching between the at least one RF power source and the process chamber;
It is configured to include a second plasma electrode installed in the process chamber facing the gas spraying part that is the first plasma electrode, wherein the second plasma electrode has a first electrode part disposed in a first region and a first region a chuck structure having a second electrode part disposed in a spaced apart second region; and
In order to control the plasma atmosphere between the gas ejection part and the chuck structure, the second plasma is connected between the ground part and the second plasma electrode to adjust an impedance on a path from the second plasma electrode to the ground part. Adjustment circuitry configured to control the RF current flowing to the electrodes;
The control circuit unit includes a first current control circuit unit connected between the ground unit and the first electrode unit and variably adjusting a first impedance on a path from the first electrode unit to the ground unit; A second current control circuit unit connected between the electrode units and variably adjusting a second impedance on a path from the second electrode unit to the ground unit,
The first current regulating circuit part and the second current regulating circuit part each include at least one RF filter for passing at least one RF current generated by the at least one RF power source and flowing through the chuck structure,
The RF filter includes at least one variable capacitor configured to variably adjust an impedance of the RF filter,
The control circuit unit determines the capacitance value of the variable capacitor corresponding to the target deposition rate of the thin film using lookup table data for a relationship between the capacitance value of the variable capacitor and the deposition rate data of the thin film, and the first current control circuit unit and the first current control circuit unit. 2 further comprising a control unit that can be set for each current control circuit unit,
Substrate processing device. A process chamber defining a processing space for processing a thin film therein;
a gas injection unit installed in the process chamber and supplying a process gas to the process space;
a plasma power supply including at least one RF power supply to apply at least one RF power to the gas dispensing part, which is a first plasma electrode, to form a plasma atmosphere into the process chamber;
an impedance matching unit connected between the plasma power supply unit and the gas dispensing unit for impedance matching between the at least one RF power source and the process chamber;
It is configured to include a second plasma electrode installed in the process chamber facing the gas spraying part that is the first plasma electrode, wherein the second plasma electrode has a first electrode part disposed in a first region and a first region a chuck structure having a second electrode part disposed in a spaced apart second region; and
In order to control the plasma atmosphere between the gas ejection part and the chuck structure, the second plasma is connected between the ground part and the second plasma electrode to adjust an impedance on a path from the second plasma electrode to the ground part. Adjustment circuitry configured to control the RF current flowing to the electrodes;
The control circuit unit includes a first current control circuit unit connected between the ground unit and the first electrode unit and variably adjusting a first impedance on a path from the first electrode unit to the ground unit; A second current control circuit unit connected between the electrode units and variably adjusting a second impedance on a path from the second electrode unit to the ground unit,
The first current regulating circuit part and the second current regulating circuit part each include at least one RF filter for passing at least one RF current generated by the at least one RF power source and flowing through the chuck structure,
The RF filter includes at least one variable capacitor configured to variably adjust an impedance of the RF filter,
The adjusting circuit unit determines the capacitance value of the variable capacitor corresponding to the target map uniformity of the thin film by using lookup table data for a relationship between the capacitance value of the variable capacitor and the map uniformity data of the thin film. Further comprising a control unit that can be set for each current control circuit unit and the second current control circuit unit,
Substrate processing device. A process chamber defining a processing space for processing a thin film therein;
a gas injection unit installed in the process chamber and supplying a process gas to the process space;
a plasma power supply including at least one RF power supply to apply at least one RF power to the gas dispensing part, which is a first plasma electrode, to form a plasma atmosphere into the process chamber;
an impedance matching unit connected between the plasma power supply unit and the gas dispensing unit for impedance matching between the at least one RF power source and the process chamber;
It is configured to include a second plasma electrode installed in the process chamber facing the gas spraying part that is the first plasma electrode, wherein the second plasma electrode has a first electrode part disposed in a first region and a first region a chuck structure having a second electrode part disposed in a spaced apart second region; and
In order to control the plasma atmosphere between the gas ejection part and the chuck structure, the second plasma is connected between the ground part and the second plasma electrode to adjust an impedance on a path from the second plasma electrode to the ground part. Adjustment circuitry configured to control the RF current flowing to the electrodes;
The control circuit unit includes a first current control circuit unit connected between the ground unit and the first electrode unit and variably adjusting a first impedance on a path from the first electrode unit to the ground unit; A second current control circuit unit connected between the electrode units and variably adjusting a second impedance on a path from the second electrode unit to the ground unit,
The first current regulating circuit part and the second current regulating circuit part each include at least one RF filter for passing at least one RF current generated by the at least one RF power source and flowing through the chuck structure,
The at least one RF power source includes a first RF power source in a first frequency band and a second RF power source in a second frequency band greater than the first frequency band to provide a dual RF power source;
The RF filter includes at least a first RF filter for passing a first RF current generated by the first RF power supply and flowing through the chuck structure, and a first RF filter generated by at least the second RF power supply to pass the first RF current flowing through the chuck structure. A second RF filter for passing a second RF current of a second frequency band flowing through the structure;
The first RF filter includes a first inductor and a first capacitor connected in parallel to each other,
The second RF filter includes a second inductor and a second capacitor connected in series with each other,
Characterized in that at least one of the first capacitor and the second capacitor is a variable capacitor configured to variably adjust the impedance of the RF filter.
Substrate processing device. According to claim 7,
The first frequency band has a frequency range of 300 kHz to 600 kHz, and the second frequency band has a frequency range of 13.56 MHz to 27.12 MHz,
Substrate processing device. delete According to claim 7,
The first RF filter further comprises a third capacitor connected in series between the parallel connection structure of the first inductor and the first capacitor and a ground. According to claim 1,
Characterized in that the first electrode part and the second electrode part are electrostatic electrodes for applying electrostatic force to a substrate seated on an upper portion of the chuck structure.
Substrate processing device. According to claim 11,
Further comprising: a constant power power supply unit including a DC power source to supply DC power to the electrostatic electrode;
The control circuit further comprises at least one DC blocking element for blocking the DC current drawn from the constant power supply.
Substrate processing device. According to claim 1,
The chuck structure further includes a heater for heating the substrate,
a heater power supply connected to the heater to apply AC power to the heater; and a third RF filter connected between the heater power supply unit and the heater. Including more,
Substrate processing device.

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