Substrate Processing Apparatus, Method of Manufacturing Semiconductor Device, and Storage Medium

Abstract

The present disclosure provides a substrate processing apparatus, a manufacturing method of a semiconductor device, and a storage medium, which can improve the in-plane uniformity of substrate processing. The substrate processing apparatus includes: a substrate processing chamber that processes a substrate; a plasma generation chamber that communicates with the substrate processing chamber; a gas supply unit that can supply a gas into the plasma generation chamber; a first coil that is disposed to surround the plasma generation chamber and is supplied with high-frequency power; and a second coil that is disposed to surround the plasma generation chamber, has the same axis as the first coil, a winding diameter different from that of the first coil, and is supplied with high-frequency power, and a peak of a voltage distribution generated by the supply of the high-frequency power does not overlap with a peak of the voltage distribution generated by the first coil.

Description

Technical Field

[0001] The present disclosure relates to a substrate processing apparatus, a method for manufacturing a semiconductor device, and a storage medium. Background Art

[0002] Patent Document 1 describes a substrate processing apparatus that performs substrate processing by plasma-exciting a processing gas by supplying high-frequency power to two coils.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-161541 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] In addition, in the above-described substrate processing apparatus, the two coils have the same diameter and are coaxially arranged. Therefore, there is a possibility that the plasma density in the in-plane direction of the substrate becomes uneven, and the in-plane uniformity of the substrate processing decreases.

[0008] An object of the present disclosure is to provide a technique capable of improving the in-plane uniformity of substrate processing.

[0009] Means for Solving the Problems

[0010] According to one aspect of the present disclosure, there is provided a technique including:

[0011] a substrate processing chamber that processes a substrate;

[0012] a plasma generation chamber that communicates with the substrate processing chamber;

[0013] a gas supply unit that can supply a gas into the plasma generation chamber;

[0014] a first coil that is arranged to surround the plasma generation chamber and is supplied with high-frequency power; and

[0015] a second coil that is arranged to surround the plasma generation chamber, has the same axis as the first coil, and a winding diameter different from that of the first coil, and is supplied with high-frequency power, and a peak of a voltage distribution generated by the supply of the high-frequency power does not overlap with a peak of a voltage distribution generated by the first coil.

[0016] Effects of the Invention

[0017] According to the present disclosure, the in-plane uniformity of substrate processing can be improved. Brief Description of the Drawings

[0018] Figure 1 This is a schematic structural diagram of a substrate processing apparatus applicable to one embodiment of the present disclosure.

[0019] Figure 2 This is a diagram showing the first resonance coil adopted in the comparative example of the present disclosure.

[0020] Figure 3 This shows Figure 2 an explanatory diagram of the relationship between current and voltage in the first resonance coil of

[0021] Figure 4 This is a diagram showing the condition inside the processing furnace when the processing gas is plasma-excited using the Figure 2 first resonance coil of

[0022] Figure 5 This is Figure 4 a horizontal cross-sectional view of the axial center portion of the first resonance coil of

[0023] Figure 6 This is a diagram showing the second resonance coil applicable to one embodiment of the present disclosure.

[0024] Figure 7 This is an explanatory diagram showing the relationship between current and voltage in the first resonance coil and the second resonance coil.

[0025] Figure 8 This is a diagram showing the condition inside the processing furnace when the processing gas is plasma-excited using the Figure 7 first resonance coil and the second resonance coil of

[0026] Figure 9 This is Figure 8 a horizontal cross-sectional view of the axial center portion of the first resonance coil and the second resonance coil of

[0027] Figure 10 This is a diagram showing the structure of the control unit (control section) of the substrate processing apparatus applicable to one embodiment of the present disclosure.

[0028] Figure 11 This is a flowchart showing the substrate processing steps applicable to one embodiment of the present disclosure.

[0029] Figure 12 This is a diagram showing the condition inside the processing furnace when the processing gas is plasma-excited using a modified example of the resonance coil applicable to one embodiment of the present disclosure.

[0030] In the figure:

[0031] 200 - wafer (substrate); 212 - first resonance coil (first coil); 214 - second resonance coil (second coil); FA - first arrangement region; SA - second arrangement region. Detailed implementation mode

[0032] A mode of the present disclosure will be described below with reference to the accompanying drawings. In addition, all the drawings used in the following description are schematic diagrams, and the dimensional relationships and ratios of the elements shown in the drawings do not necessarily conform to the actual situation. In addition, the dimensional relationships and ratios of the elements are not necessarily the same between the drawing surfaces.

[0033] (1) Structure of the substrate processing apparatus

[0034] The following uses Figures 1 - 10 to describe the substrate processing apparatus 100 of a mode of the present disclosure. The substrate processing apparatus of a mode of the present disclosure is configured to mainly perform oxidation processing on a film and a substrate formed on the substrate surface.

[0035] (Processing chamber)

[0036] The substrate processing apparatus 100 includes a processing furnace 202 that performs plasma processing on a wafer 200 as a substrate. A processing container 203 that constitutes a processing chamber 201 is provided in the processing furnace 202. The processing container 203 includes: an upper container 210 of a dome shape as a first container, and a lower container 211 of a bowl shape as a second container. The upper container 210 covers the lower container 211 to form the processing chamber 201. The upper container 210 constitutes a plasma container, and the plasma container forms a plasma generation space 201A for plasma excitation of the processing gas.

[0037] In addition, a gate valve 244 is provided on the lower side wall of the lower container 211. The gate valve 244 is configured such that when it is opened, the wafer 200 can be loaded into the processing chamber 201 via a loading / unloading port 245 by a transfer mechanism (not shown), or the wafer 200 can be unloaded from the processing chamber 201. The gate valve 244 is configured to be an isolation valve that maintains the airtightness of the processing chamber 201 when it is closed.

[0038] The processing chamber 201 has a plasma generation space 201A and a substrate processing space 201B. The plasma generation space 201A is a space surrounded by coils serving as electrodes, namely a first resonance coil 212 and a second resonance coil 214, and is a space for generating plasma. The plasma generation space 201A refers to a space within the processing chamber 201 that is above the lower end of the first resonance coil 212 and below the upper end of the first resonance coil 212. The substrate processing space 201B communicates with the plasma generation space 201A and is a space for processing the wafer 200. The substrate processing space 201B is a space for processing the wafer 200 using plasma and refers to a space below the lower end of the first resonance coil 212. In one embodiment of the present disclosure, the horizontal diameters of the plasma generation space 201A and the substrate processing space 201B are substantially the same. The structure forming the plasma generation space 201A is also referred to as a plasma generation chamber, and the structure forming the substrate processing space is also referred to as a substrate processing chamber. Additionally, the plasma generation space 201A may also be renamed as the plasma generation region within the processing chamber 201. Additionally, the substrate processing space 201B may also be renamed as the substrate processing region within the processing chamber 201.

[0039] (Chuck)

[0040] A chuck (substrate mounting table) 217 is disposed at the center of the bottom side of the processing chamber 201. The chuck 217 is a substrate mounting portion for mounting the wafer 200. The chuck 217 is disposed below the first resonance coil 212 within the processing chamber 201.

[0041] A heater 217B serving as a heating mechanism is integrally embedded inside the chuck 217. The heater 217B is configured to be able to heat the wafer 200 when powered on.

[0042] The chuck 217 is electrically insulated from the lower container 211. An impedance adjustment electrode 217C is disposed inside the chuck 217 to further improve the uniformity of the density of the plasma generated on the wafer 200 mounted on the chuck 217. And the impedance adjustment electrode 217C is grounded via an impedance variable mechanism 275 serving as an impedance adjustment unit.

[0043] A chuck lifting mechanism 268 is disposed on the chuck 217, which has a driving mechanism for lifting and lowering the chuck 217. Additionally, a through hole 217A is provided on the chuck 217, and a wafer lift pin 266 is provided on the bottom surface of the lower container 211. When the chuck 217 is lowered by the chuck lifting mechanism 268, the wafer lift pin 266 disengages from the through hole 217A in a state of not contacting the chuck 217.

[0044] (Gas supply unit)

[0045] Above the processing chamber 201, that is, above the upper container 210, a gas supply head 236 is provided. The gas supply head 236 includes: a cap-shaped lid 233, a gas inlet 234, a buffer chamber 237, an opening 238, a shielding plate 240, and a gas outlet 239, and is configured to supply a reaction gas into the processing chamber 201. The buffer chamber 237 functions as a dispersion space that disperses the reaction gas introduced from the gas inlet 234.

[0046] The downstream end of the oxygen-containing gas supply pipe 232A that supplies oxygen-containing gas, the downstream end of the hydrogen-containing gas supply pipe 232B that supplies hydrogen-containing gas, and the inert gas supply pipe 232C that supplies inert gas are connected to the gas inlet 234 in a manner that they merge in the merge pipe 232. The oxygen-containing gas supply pipe 232A is also simply referred to as the gas supply pipe 232A, the hydrogen-containing gas supply pipe 232B is also simply referred to as the gas supply pipe 232B, and the inert gas supply pipe 232C is also simply referred to as the gas supply pipe 232C. On the oxygen-containing gas supply pipe 232A, the following are sequentially provided from the upstream side: an oxygen-containing gas supply source 250A, a mass flow controller (MFC) 252A as a flow control device, and a valve 253A as an on-off valve. On the hydrogen-containing gas supply pipe 232B, the following are sequentially provided from the upstream side: a hydrogen-containing gas supply source 250B, an MFC 252B, and a valve 253B. On the inert gas supply pipe 232C, the following are sequentially provided from the upstream side: an inert gas supply source 250C, an MFC 252C, and a valve 253C. A valve 243A is provided on the downstream side where the oxygen-containing gas supply pipe 232A, the hydrogen-containing gas supply pipe 232B, and the inert gas supply pipe 232C merge, and is connected to the upstream end of the gas inlet 234. It is configured such that by opening and closing the valves 253A, 253B, 253C, and 243A, the flow rates of the respective gases can be adjusted using the MFCs 252A, 252B, and 252C, and the processing gases such as oxygen-containing gas, hydrogen-containing gas, and inert gas are supplied into the processing chamber 201 via the gas supply pipes 232A, 232B, and 232C.

[0047] In addition, it is configured that the oxygen-containing gas supply pipe 232A, the MFC 252A, the valve 253A, and the valve 243A constitute an oxygen-containing gas supply system according to one aspect of the present disclosure. In addition, the hydrogen-containing gas supply pipe 232B, the MFC 252B, the valve 253B, and the valve 243A constitute a hydrogen-containing gas supply system according to one aspect of the present disclosure. In addition, the inert gas supply pipe 232C, the MFC 252C, the valve 253C, and the valve 243A constitute an inert gas supply system according to one aspect of the present disclosure.

[0048] Mainly, an oxygen-containing gas supply pipe 232A, a hydrogen-containing gas supply pipe 232B, an inert gas supply pipe 232C, MFCs 252A, 252B, 252C, valves 253A, 253B, 253C, and valve 243A constitute a gas supply unit (gas supply system) according to one embodiment of the present disclosure. The gas supply unit (gas supply system) only needs to be configured to be able to supply a processing gas into the processing container 203. For example, any gas supply system or a combination thereof can be referred to as the gas supply unit.

[0049] (Exhaust unit)

[0050] A gas discharge port 235 is provided on the side wall of the lower container 211. The gas discharge port 235 is used to discharge the reaction gas from the inside of the processing chamber 201. The upstream end of a gas discharge pipe 231 is connected to the gas discharge port 235. On the gas discharge pipe 231, an APC (Auto Pressure Controller) valve 242 as a pressure regulator (pressure regulating unit), a valve 243B as an on-off valve, and a vacuum pump 246 as a vacuum exhaust device are provided in sequence from the upstream side. Mainly, the gas discharge port 235, the gas discharge pipe 231, the APC valve 242, and the valve 243B constitute an exhaust unit according to one embodiment of the present disclosure. In addition, the vacuum pump 246 can also be included in the exhaust unit.

[0051] (Plasma generation unit)

[0052] Outside the processing container 203, a first resonance coil 212 and a second resonance coil 214 are respectively arranged so as to surround the outer periphery of the processing container 203. Specifically, the first resonance coil 212 and the second resonance coil 214 are respectively arranged so as to surround the outer periphery (the outer periphery of the plasma generation chamber) of the part (area) of the processing container 203 corresponding to the plasma generation space 201A.

[0053] The first resonance coil 212 is formed by spirally winding a linear or strip-shaped conductor 212A in the same direction for multiple turns. Both ends of the first resonance coil 212 (at Figure 8The upper end 212B and the lower end 212C are grounded respectively, and the portion between the two ends of the first resonance coil 212 surrounds the outer periphery of the processing container 203. Specifically, the first resonance coil 212 surrounds the outer peripheral portion of the processing chamber 201, that is, the outer periphery of the side wall of the upper container 210. In other words, the processing container 203 is inserted inside the first resonance coil 212. In addition, in the present embodiment, the first resonance coil 212 is brought close to the outer periphery (outer surface) of the processing container 203 to such an extent that the high-frequency electromagnetic field generated by the first resonance coil 212 substantially plasma-excites the processing gas inside the processing container 203. In addition, the winding diameter of the first resonance coil 212 in the present embodiment is constant and the same at any position on the first resonance coil 212. The first resonance coil 212 is configured to be supplied with high-frequency power.

[0054] The second resonance coil 214 is formed by spirally winding a linear or strip-shaped conductor 214A in the same direction for a plurality of turns. The two ends (the upper end 214B and the lower end 214C) of the second resonance coil 214 are grounded respectively, and the portion between the upper end 214B and the lower end 214C of the second resonance coil 214 surrounds the outer periphery of the processing container 203. Specifically, the second resonance coil 214 surrounds the outer peripheral portion of the processing chamber 201, that is, the outer periphery of the side wall of the upper container 210. In other words, the processing container 203 is inserted inside the second resonance coil 214. In the present embodiment, similarly to the first resonance coil 212, the second resonance coil 214 is brought close to the outer periphery (outer surface) of the processing container 203 to such an extent that the high-frequency electromagnetic field generated by the second resonance coil 214 substantially plasma-excites the processing gas inside the processing container 203. In addition, the winding diameter of the second resonance coil 214 in the present embodiment is constant and the same at any position on the second resonance coil 214. In addition, in the present embodiment, the winding diameter D1 of the first resonance coil 212 and the winding diameter D2 of the second resonance coil 214 are different. Specifically, the winding diameter D2 of the second resonance coil 214 is larger than the winding diameter D1 of the first resonance coil 212. Here, the winding diameter D2 is set in the range of 101% to 125% of the winding diameter D1, preferably in the range of 105% to 120%.

[0055] As Figure 8 shown, the axial direction of the first resonance coil 212 (that is, the direction along the spiral axis of the first resonance coil 212) and the axial direction of the second resonance coil 214 (that is, the direction along the spiral axis of the second resonance coil 214) are in the same direction. Specifically, in the present embodiment, the spiral axis of the first resonance coil 212 and the spiral axis of the second resonance coil 214 are coaxial. In addition, in the present embodiment, the axial direction of each resonance coil is the same direction as the up-down direction of the device and is also the same direction as the vertical direction (perpendicular direction). In addition, in Figure 7In the figure, arrow U indicates above the device, and arrow R indicates the radial direction of the processing container 203. Here, the radial direction of the processing container 203 is the same as the horizontal direction of the device and is also the same as the direction orthogonal to the helical axis of each resonance coil. In addition, the conductor 212A constituting the first resonance coil 212 and the conductor 214A constituting the second resonance coil 214 are alternately arranged in the vertical direction (axial direction of the resonance coil). Here, when the first resonance coil 212 and the second resonance coil 214 are viewed from the vertical direction, the outer peripheral portion of the first resonance coil 212 overlaps the inner peripheral portion of the second resonance coil 214. In this way, when viewed from the vertical direction, a part of the first resonance coil 212 overlaps a part of the second resonance coil 214, so that an increase in the radial dimension of the container (not shown) covering each coil can be suppressed. On the other hand, when viewed from the vertical direction, the first resonance coil 212 and the second resonance coil 214 do not overlap, that is, when there is a gap between the first resonance coil 212 and the second resonance coil 214, the distance between the first resonance coil 212 and the second resonance coil 214 can be ensured, and the occurrence of arc discharge can be suppressed. In addition, the distance between the first resonance coil 212 and the second resonance coil 214 can be set in advance to a distance at which arc discharge does not occur. In addition, the second resonance coil 214 is configured to be supplied with high-frequency power.

[0056] As Figure 8 shown, the axial length (length along the helical axis) of the coil portion of the first resonance coil 212 is longer than the axial length (length along the helical axis) of the coil portion of the second resonance coil 214. Therefore, the conductor 214A of the second resonance coil 214 is alternately arranged in the vertical direction (axial direction of the resonance coil) relative to the conductor 212A of the first resonance coil 212 from the upper side to the vicinity of the central portion in the vertical direction. Here, a region for arranging the first resonance coil 212 and the second resonance coil 214 is formed on the outer periphery of the processing container 203. Specifically, the region for arranging the first resonance coil 212 and the second resonance coil 214 is referred to as the first arrangement region and is denoted by the symbol FA (refer to Figure 8 ). In addition, the region where only the first resonance coil 212 is arranged is referred to as the second arrangement region and is denoted by the symbol SA (refer to Figure 8 ). The second arrangement region SA is formed on the side closer to the base 217 than the first arrangement region FA in the up-down direction (vertical direction) of the device.

[0057] Connected to the first resonance coil 212 are: an RF sensor 272, a high-frequency power supply 273, and a matcher 274 that matches the impedance and output frequency of the high-frequency power supply 273.

[0058] The high-frequency power supply 273 supplies high-frequency power (RF power) to the resonance coil 212. The RF sensor 272 is provided on the output side of the high-frequency power supply 273 and monitors the information on the forward wave and reflected wave of the supplied high-frequency power. The reflected wave power monitored by the RF sensor 272 is input to the matcher 274, and the matcher 274 controls the impedance of the high-frequency power supply 273 and the frequency of the output high-frequency power in such a way as to minimize the reflected wave based on the information on the reflected wave input from the RF sensor 272.

[0059] The high-frequency power supply 273 includes: a power supply control unit (control circuit) that includes a high-frequency oscillation circuit and a preamplifier for specifying the oscillation frequency and output; and an amplifier (output circuit) for amplifying to the specified output. The power supply control unit controls the amplifier based on the output conditions related to frequency and power preset through the operation panel. The amplifier supplies constant high-frequency power to the resonance coil 212 via a transmission line. The RF sensor 272 and the matcher 274 are collectively referred to as the high-frequency power supply unit 271. The high-frequency power supply 273 may also be included in the high-frequency power supply unit 271.

[0060] Connected to the second resonance coil 214 are: an RF sensor 282, a high-frequency power supply 283, and a matcher 284 that matches the impedance and output frequency of the high-frequency power supply 283.

[0061] The high-frequency power supply 283 supplies high-frequency power (RF power) to the second resonance coil 214. The RF sensor 282 is provided on the output side of the high-frequency power supply 283 and monitors the information on the forward wave and reflected wave of the supplied high-frequency power. The reflected wave power monitored by the RF sensor 282 is input to the matcher 284, and the matcher 284 controls the impedance of the high-frequency power supply 283 and the frequency of the output high-frequency power in such a way as to minimize the reflected wave based on the information on the reflected wave input from the RF sensor 282.

[0062] The high-frequency power supply 283 includes: a power supply control unit (control circuit) that includes a high-frequency oscillation circuit and a preamplifier for specifying the oscillation frequency and output; and an amplifier (output circuit) for amplifying to the specified output. The power supply control unit controls the amplifier based on the output conditions related to frequency and power preset through the operation panel. The amplifier supplies constant high-frequency power to the second resonance coil 214 via a transmission line. The RF sensor 282 and the matcher 284 are collectively referred to as the high-frequency power supply unit 281. The high-frequency power supply 283 may also be included in the high-frequency power supply unit 281.

[0063] The first resonant coil 212 forms a standing wave of a predetermined wavelength. Therefore, the winding diameter, winding pitch, and number of winding turns are set to resonate at a constant wavelength. That is, the electrical length of the first resonant coil 212 is set to a length corresponding to an integer multiple (1 times, 2 times, …) of one wavelength at a predetermined frequency of the high-frequency power supplied from the high-frequency power supply 273.

[0064] In addition, the second resonant coil 214 sets the winding diameter, winding pitch, and number of winding turns so as to resonate at a constant wavelength in order to form a standing wave of a predetermined wavelength. That is, the electrical length of the second resonant coil 214 is set to a length corresponding to an integer multiple (1 times, 2 times, …) of one wavelength at a predetermined frequency of the high-frequency power supplied from the high-frequency power supply 283.

[0065] Specifically, considering the applied power, the generated magnetic field strength, or the shape of the device to be applied, etc., the first resonant coil 212 is set, for example, to be able to generate a magnetic field of about 0.01 to 10 gauss using high-frequency power of 800 kHz to 50 MHz and 0.1 to 5 kW. And the first resonant coil 212 is set to have a cross-sectional area of 50 to 300 mm 2 and a coil diameter of 200 to 500 mm, and is wound 2 to 60 turns on the outer peripheral side of the chamber forming the plasma generation space 201A.

[0066] Similarly, considering the applied power, the generated magnetic field strength, or the shape of the device to be applied, etc., the second resonant coil 214 is set, for example, to be able to generate a magnetic field of about 0.01 to 10 gauss using high-frequency power of 800 kHz to 50 MHz and 0.1 to 5 kW. And the second resonant coil 214 is set to have a cross-sectional area of 50 to 300 mm 2 and a coil diameter of 200 to 500 mm, and is wound 2 to 60 turns on the outer peripheral side of the chamber forming the plasma generation space 201A.

[0067] As Figure 7 shown, the first resonant coil 212 and the second resonant coil 214 are arranged such that the positions of the wave antinodes of the standing wave do not overlap. In other words, the peak of the voltage distribution of the first resonant coil 212 and the peak of the voltage distribution of the second resonant coil 214 do not overlap. In addition, the distance between the first resonant coil 212 and the second resonant coil 214 is set to a distance at which arc discharge does not occur between the conductors of each resonant coil.

[0068] As materials for forming the first resonance coil 212 and the second resonance coil 214, copper pipes, thin copper plates, aluminum pipes, thin aluminum plates, materials formed by vapor-depositing copper or aluminum on a polymer tape, etc. can be used. The first resonance coil 212 and the second resonance coil 214 are formed into a flat plate shape by an insulating material and are supported by a plurality of support members (not shown) vertically erected on the upper end surface of the bottom plate 248.

[0069] Both ends of the first resonance coil 212 are electrically grounded. Among the two ends of the first resonance coil 212, one end (the upper end in Figure 1 and Figure 2 is 212B) is grounded via a movable contact 300 in order to finely adjust the electrical length of the first resonance coil 212 when the device is initially set up or when the processing conditions are changed. In addition, the other end of the first resonance coil 212 (the lower end in Figure 1 and Figure 6 is 212C) is grounded as a fixed ground. In addition, in order to finely adjust the impedance of the first resonance coil 212 when the device is initially set up or when the processing conditions are changed, a power supply unit is formed by a movable contact 305 between the grounded two ends of the first resonance coil 212. In addition, the movable contact 305 adjusts its position so that the resonance characteristics of the first resonance coil 212 are approximately equal to those of the high-frequency power supply 273. Since the first resonance coil 212 has a variable grounding part and a variable power supply part, as will be described later, when adjusting the resonance frequency and load impedance of the processing chamber 201, the adjustment can be performed more simply. In addition, the upper end 212B of the first resonance coil 212 of the present embodiment is an example of the first ground connection part of the present disclosure. In addition, the lower end 212C of the first resonance coil 212 is an example of the second ground connection part of the present disclosure. In addition, when the vicinity of the upper end 212B of the first resonance coil 212 is grounded, this part becomes a ground point and becomes the first ground connection part. And when the vicinity of the lower end 212C of the first resonance coil 212 is grounded, this part becomes a ground point and becomes the second ground connection part.

[0070] Both ends of the second resonance coil 214 are electrically grounded. Among the two ends of the second resonance coil 214, one end (the upper end in Figure 1 and Figure 6 is 214B) is grounded via a movable contact 302 in order to finely adjust the electrical length of the second resonance coil 212 when the device is initially set up or when the processing conditions are changed. In addition, the other end of the first resonance coil 212 (in Figure 1 and Figure 6The lower end 214B is grounded as a fixed ground. In addition, in order to finely adjust the impedance of the second resonance coil 214 when the device is initially set up or when the processing conditions are changed, a power supply unit is formed by a movable contact 306 between the two ends of the second resonance coil 214 that are grounded. Additionally, the movable contact 306 adjusts its position in such a way that the resonance characteristics of the second resonance coil 214 are approximately equal to those of the high-frequency power supply 283. Since the second resonance coil 214 has a variable grounding portion and a variable power supply portion, as will be described later, when adjusting the resonance frequency and load impedance of the processing chamber 201, the adjustment can be carried out more simply. In addition, the upper end 214B of the second resonance coil 214 in this embodiment is an example of the third grounding connection portion of the present disclosure. Also, the lower end 214C of the second resonance coil 212 is an example of the fourth grounding connection portion of the present disclosure. Moreover, when the vicinity of the upper end 214B of the second resonance coil 214 is grounded, this portion becomes the ground point and becomes the third grounding connection portion. And when the vicinity of the lower end 214C of the second resonance coil 214 is grounded, this portion becomes the ground point and becomes the fourth grounding connection portion.

[0071] In such a way that the phase current and the anti-phase current flow symmetrically with respect to the electrical midpoint of the first resonance coil 212, a waveform adjustment circuit 308 composed of a resonance coil and a shielding portion is inserted into at least one of one end and the other end of the first resonance coil 212. The waveform adjustment circuit 308 forms an open circuit by setting the first resonance coil 212 to a non-electrically connected state or to an electrically equivalent state. Additionally, it is also possible that the end of the first resonance coil 212 is not grounded using a choke series resistor and is directly connected to a fixed reference potential in DC.

[0072] Also, in such a way that the phase current and the anti-phase current flow symmetrically with respect to the electrical midpoint of the second resonance coil 214, a waveform adjustment circuit 309 composed of a resonance coil and a shielding portion is inserted into at least one of one end and the other end of the second resonance coil 214. The waveform adjustment circuit 309 forms an open circuit by setting the second resonance coil 214 to a non-electrically connected state or to an electrically equivalent state. Additionally, it is also possible that the end of the second resonance coil 214 is not grounded using a choke series resistor and is directly connected to a fixed reference potential in DC.

[0073] In addition, the waveform adjustment circuit only needs to be arranged in at least one of the first resonance coil 212 and the second resonance coil 214. Here, as the waveform adjustment circuits 308 and 309, for example, a variable capacitor can be used, or it can also be a wire (coil) composed of a conductor.

[0074] The shielding plate 223 is provided to shield the electric field outside the first resonance coil 212 and the second resonance coil 214, and to form a capacitance component (C component) required for constituting a resonance circuit between the shielding plate 223 and the first resonance coil 212 or the second resonance coil 214. The shielding plate 223 is generally formed in a cylindrical shape using a conductive material such as aluminum alloy. The shielding plate 223 is arranged at a distance of about 5 to 150 mm from the outer periphery of each of the first resonance coil 212 and the second resonance coil 214.

[0075] Mainly, the first plasma generation unit of one embodiment of the present disclosure is constituted by the first resonance coil 212, the RF sensor 272, and the matcher 274. In addition, the high-frequency power supply 273 may also be included as the first plasma generation unit.

[0076] In addition, mainly, the second plasma generation unit of one embodiment of the present disclosure is constituted by the second resonance coil 214, the RF sensor 282, and the matcher 284. In addition, the high-frequency power supply 283 may also be included as the second plasma generation unit.

[0077] The first plasma generation unit and the second plasma generation unit are collectively referred to as the plasma generation unit.

[0078] Next, the plasma generation principle of the device of one embodiment of the present disclosure and the properties of the generated plasma will be described. The plasma generation principles of the first resonance coil 212 and the second resonance coil 214 are the same, so here, the case of using one first resonance coil 212 will be taken as an example for description (refer to Figures 3 - 5 ).

[0079] Regarding the plasma generation circuit constituted by the first resonance coil 212, it is constituted by a parallel resonance circuit of RLC. When the wavelength of the high-frequency power supplied from the high-frequency power supply 273 is the same as the electrical length of the first resonance coil 212, the resonance condition of the first resonance coil 212 is such that the reactance components generated by the capacitance component or the inductance component of the first resonance coil 212 cancel each other out to become a pure resistance. However, when plasma is generated in the above plasma generation circuit, due to changes in the capacitive coupling between the voltage part of the first resonance coil 212 and the plasma, changes in the inductive coupling between the plasma generation space 201A and the plasma, and the excitation state of the plasma, etc., the actual resonance frequency will change slightly.

[0080] Therefore, regarding the substrate processing apparatus 100 according to one aspect of the present disclosure, in order to compensate for the deviation of the resonance of the first resonance coil 212 during plasma generation on the power supply side, the reflected wave power emitted from the first resonance coil 212 during plasma generation is detected by the RF sensor 272, and the matcher 274 has a function of correcting the output of the high-frequency power supply 273 based on the detected reflected wave power.

[0081] Specifically, the matcher 274 increases or decreases the impedance or output frequency of the high-frequency power supply 273 in such a way that the reflected wave power is minimized based on the reflected wave power emitted from the first resonance coil 212 during plasma generation detected by the RF sensor 272. When controlling the impedance, the matcher 274 is composed of a variable capacitor control circuit that corrects a preset impedance. When controlling the frequency, the matcher 274 is composed of a frequency control circuit that corrects the oscillation frequency of the preset high-frequency power supply 273. In addition, the high-frequency power supply 273 and the matcher 274 may be integrated.

[0082] According to the above structure, in the first resonance coil 212 according to one aspect of the present disclosure, since high-frequency power based on the actual resonance frequency of the resonance coil including plasma is supplied (or high-frequency power is supplied in a manner that matches the actual impedance of the resonance coil including plasma), a standing wave in a state where the phase voltage and the anti-phase voltage always cancel each other out is formed (refer to Figure 3 ). And, when the electrical length of the first resonance coil 212 is the same as the wavelength of the high-frequency power, the highest phase current is generated at the electrical midpoint (the node where the voltage is zero) of the first resonance coil 212. Specifically, high-frequency power is supplied from the high-frequency power supply 273 to the first resonance coil 212, and a standing wave of current and voltage having a length of, for example, one wavelength of the high-frequency power is formed in the interval between both ends on the line of the first resonance coil 212. In Figure 3 the waveform on the right side, the dotted line represents the current and the solid line represents the voltage. As shown in the waveform on the right side of Figure 3 , the amplitude of the standing wave of the current is the largest at both ends and the midpoint (i.e., the electrical midpoint) of the first resonance coil 212.

[0083] Near the electrical midpoint of the first resonance coil 212, there is almost no capacitive coupling with the processing chamber wall or the susceptor 217, and a toroidal inductively coupled plasma (ICP) 310 with an extremely low potential is formed. Specifically, a high-frequency magnetic field is formed near the electrical midpoint of the first resonance coil 212 where the amplitude of the current is the largest. The high-frequency electromagnetic field induced by this high-frequency magnetic field causes the discharge of the processing gas supplied into the plasma generation space 201A inside the upper container 210. Along with this discharge, the processing gas is excited, and plasma of the processing gas is generated near the electrical midpoint of the first resonance coil 212. Hereinafter, the plasma of the processing gas generated by the high-frequency electromagnetic field formed near the position (region) where the amplitude of the current is large will be referred to as inductively coupled plasma. As Figure 4 shown, in the space along the inner wall surface inside the upper container 210, ICP is generated in a toroidal shape in the region near the midpoint of the first resonance coil 212, and ICP with a uniform plasma density is generated in the in-plane direction of the wafer 200. In addition, based on the same principle, inductively coupled plasma is also generated at both axial ends of the first resonance coil 212.

[0084] Next, the state of generating plasma using the first resonance coil 212 and the second resonance coil 214 will be described.

[0085] In Figure 8 the substrate processing apparatus 100 according to one embodiment of the present disclosure shown, similar to the embodiment where there is only one first resonance coil 212 as shown in Figure 4 , the first resonance coil 212 and the second resonance coil 214 are respectively arranged around the plasma generation space 201A. And if high-frequency power is supplied to the first resonance coil 212 in a state where the processing gas is supplied to the plasma generation space 201A, based on the aforementioned principle, voltage and current are generated as shown on the right side of Figure 7 , and ICP 310 is generated in the plasma generation space 201A as shown in Figure 8 .

[0086] Similarly, if high-frequency power is supplied to the second resonance coil 214 in a state where the processing gas is supplied to the plasma generation space 201A, based on the aforementioned principle, voltage and current are generated as shown on the left side of Figure 7 , and ICP 312 is generated in the plasma generation space 201A as shown in Figure 8 .

[0087] By using multiple resonance coils in this way, compared with the case of generating plasma using one resonance coil, more plasma can be generated. That is, more radical components in the plasma can be generated.

[0088] In this embodiment, the winding diameter D2 of the second resonant coil 214 is made different from the winding diameter D1 of the first resonant coil 212, so that Figure 7 As shown in FIG. 1 , the peak value of the voltage distribution of the first resonant coil 212 and the peak value of the voltage distribution of the second resonant coil 214 are shifted in the radial direction. That is, the peak values of the voltage distribution of each resonant coil do not overlap. By shifting the peak values of the voltage distribution of the two resonant coils in this way, the density of the inductively coupled plasma with a high concentration can be made uniform in the radial direction (see FIG. 1 ). Figure 9 ). This makes it possible to achieve uniformity within the substrate surface (within the wafer surface).

[0089] In addition, the second resonant coil 214 of this embodiment is configured so that the peak of the voltage distribution in the direction orthogonal to the axial direction (horizontal direction) does not overlap with the peak of the voltage distribution of the first resonant coil 212. By shifting the peak of the voltage distribution in the horizontal direction in this way, the plasma density can be made uniform. Figure 9 As shown, ICPs are formed at different locations from the two resonant coils, thereby increasing the amount of plasma in the radial direction.

[0090] Furthermore, in this embodiment, second resonant coil 214 is configured so that the peak of its voltage distribution in the axial (vertical) direction does not overlap with the peak of the voltage distribution of first resonant coil 212. By shifting the peaks of the vertical voltage distribution in this manner, the coarse state of one inductively coupled plasma can be compensated for by the other inductively coupled plasma. This can extend the overall life of the inductively coupled plasma.

[0091] Furthermore, in this embodiment, a first arrangement area FA and a second arrangement area SA are formed on the outer periphery of the processing container 203. Since only the first resonant coil 212 is continuously arranged in the second arrangement area SA, the physical length of the coil relative to the plasma generation space 201A can be adjusted. This ensures flexibility in design.

[0092] Furthermore, in this embodiment, the winding diameter D1 of the first resonant coil 212 is smaller than the winding diameter D2 of the second resonant coil 214. This allows the peak of the voltage distribution to be formed with a smaller winding diameter than the second resonant coil 214, thereby supplying high-density inductively coupled plasma to the center of the substrate (wafer).

[0093] In addition, the second configuration region SA of the present embodiment is formed on the side closer to the susceptor 217 on which the wafer 200 is placed in the processing container 203 in the axial direction (vertical direction). Here, by making the winding diameter of the resonance coil on the side closer to the susceptor 217 smaller, it becomes easier to supply plasma to the central region of the wafer 200 directly below.

[0094] In addition, the processing container 203 of the present embodiment has an exhaust portion capable of exhausting the processing gas from the outer periphery of the susceptor 217. Thereby, it is possible to diffuse the flow of the inductively coupled plasma supplied to the central region of the wafer 200 toward the outer periphery of the susceptor 217. That is, it is possible to diffuse the high-density plasma supplied to the central region of the wafer toward the outer periphery, and thus it is possible to make the processing on the surface of the wafer 200 uniform.

[0095] In addition, in the present embodiment, it is configured such that in the first configuration region FA, the conductor 212A of the first resonance coil 212 and the conductor 214A of the second resonance coil 214 are separated by a distance at which arc discharge does not occur. And it is configured such that in the second configuration region SA, the conductors 212A of the first resonance coil 212 are separated by a distance at which arc discharge does not occur. Here, when the voltage difference between the resonance coils reaches a threshold value or more, arc discharge occurs, which may cause power leakage, and when leakage occurs, the required inductively coupled plasma cannot be formed. In response to this, in the present embodiment, the conductors 212A and the conductor 214A are made to be at a distance at which arc discharge does not occur to suppress leakage, so that the required inductively coupled plasma can be formed.

[0096] In addition, the first resonance coil 212 of the present embodiment is configured such that the electrical length between the grounded two ends is a length that is a multiple of the wavelength of the high-frequency power supplied to the first resonance coil 212. By grounding the two ends of the first resonance coil in this way, it is possible to form a multiple of the wavelength of the supplied high-frequency power. Thereby, it is possible to form Figure 7 the sine curve of the voltage shown, and thus it is easy to control the peak of the voltage distribution of the first resonance coil 212.

[0097] In addition, the second resonance coil 214 of the present embodiment is configured such that the electrical length between the grounded two ends is a length that is a multiple of the wavelength of the high-frequency power supplied to the second resonance coil 214. By grounding the two ends of the second resonance coil 214 in this way, it is possible to form a multiple of the wavelength of the supplied high-frequency power. Thereby, it is possible to form Figure 7 the sine curve of the voltage shown, and thus it is easy to control the peak of the voltage distribution of the second resonance coil 214.

[0098] In addition, in the present embodiment, in order to make the electrical lengths of the first resonance coil 212 and the second resonance coil 214 equal, waveform adjustment circuits 308 and 309 for correcting the electrical length are connected to both the first resonance coil 212 and the second resonance coil 214. In the case where adjustment cannot be made by grounding, the waveform adjustment circuits 308 and 309 can be used to adjust the electrical length as described above.

[0099] In addition, in the present embodiment, it is configured such that the upper end 212B of the ground connection of the first resonance coil 212 is different in position in the vertical direction from the upper end 214B of the ground connection of the second resonance coil 214. By making the ground connection heights of the upper ends of the respective resonance coils different in this way, it is possible to more reliably shift the positions of the peaks of the voltage distribution.

[0100] In addition, in the present embodiment, it is configured such that the lower end 212C of the ground connection of the first resonance coil 212 is different in position in the vertical direction from the lower end 214C of the ground connection of the second resonance coil 214. By making the ground connection heights of the lower ends of the respective resonance coils different in this way, it is possible to more reliably shift the positions of the peaks of the voltage distribution.

[0101] In addition, in the present embodiment, the high frequency generated from the high frequency power supply 273 connected to the first resonance coil 212 and the high frequency generated from the high frequency power supply 283 connected to the second resonance coil 214 are of the same frequency. If the frequencies of the high frequency power supplies 273 and 283 are made the same in this way, it is possible to make the wavelengths of the high frequency power supplies 273 and 283 the same, and thus it is easy to control the positions of the peaks of the voltage distribution.

[0102] In addition, in the present embodiment, a controller 221 described later controls the supply of the processing gas to the processing chamber 201 in a state where high frequency power is supplied to the first resonance coil 212 and the second resonance coil 214. Therefore, it is possible to generate two types of inductively coupled plasmas in the plasma generation space 201A, and thus it is possible to more reliably equalize the inductively coupled plasmas.

[0103] (Control unit)

[0104] Regarding the controller 221 serving as the control unit, it is configured to control the APC valve 242, valve 243B, and vacuum pump 246 via signal line A. Additionally, the controller 221 is configured to control the base lifting mechanism 268 via signal line B. Further, the controller 221 is configured to control the heater power adjustment mechanism 276 and impedance variable mechanism 275 via signal line C. Moreover, the controller 221 is configured to control the gate valve 244 via signal line D. Additionally, the controller 221 is configured to control the RF sensors 272, high-frequency power supplies 273, matchers 274, RF sensors 282, high-frequency power supplies 283, and matchers 284 via signal line E. Further, the controller 221 is configured to control the MFCs 252A to 252C, valves 253A to 253C, and valve 243A via signal line F.

[0105] As Figure 10 shown, the control unit (control unit), namely the controller 221, is composed of a computer, which includes: a CPU (Central Processing Unit) 221A, a RAM (Random Access Memory) 221B, a storage device 221C, and an I / O port 221D. The RAM 221B, storage device 221C, and I / O port 221D are configured to be able to perform data exchange with the CPU 221A via the internal bus 221E. An input / output device 225, which is composed of a touch panel, a display, etc., is connected to the controller 221, for example.

[0106] The storage device 221C is composed of a flash memory, an HDD (Hard Disk Drive), etc., for example. Stored in a readable manner in the storage device 221C are: a control program for controlling the operation of the substrate processing apparatus, a program recipe, etc., which records the substrate processing steps or conditions described later. The process recipe is combined to enable the controller 221 to execute each step in the substrate processing process described later to obtain a predetermined result, and functions as a program. Hereinafter, the program recipe, control program, etc. will also be simply referred to as programs. In addition, in this specification, the meaning of "program" includes: only the program recipe itself, only the control program itself, or both of the above. Further, the RAM 221B is configured as a storage area (work area) to temporarily hold programs, data, etc. read by the CPU 221A.

[0107] Connected to the I / O port 221D are: the above-mentioned MFCs 252A to 252C, valves 253A to 253C, valves 243A, 243B, gate valve 244, APC valve 242, vacuum pump 246, RF sensor 272, high-frequency power supply 273, matcher 274, RF sensor 282, high-frequency power supply 283, matcher 284, susceptor lifting mechanism 268, impedance variable mechanism 275, heater power adjustment mechanism 276, etc.

[0108] The CPU 221A reads and executes the control program from the storage device 221C, and is configured to read the process recipe from the storage device 221C according to operation instructions input from the input / output device 225, etc. Further, the CPU 221A controls, according to the content of the read process recipe and via the I / O port 221D and signal line A: the opening adjustment operation of the APC valve 242, the opening and closing operation of the valve 243B, and the start and stop of the vacuum pump 246. In addition, the CPU 221A is configured to control the lifting operation of the susceptor lifting mechanism 268 according to the content of the above process recipe and via signal line B. In addition, the CPU 221A is configured to control, according to the content of the above process recipe and via signal line C: the adjustment operation (temperature adjustment operation) of the amount of power supplied to the opposing heater 217B by the heater power adjustment mechanism 276, and the impedance value adjustment operation by the impedance variable mechanism 275. In addition, the CPU 221A is configured to control the opening and closing operation of the gate valve 244 according to the content of the above process recipe and via signal line D. In addition, the CPU 221A is configured to control, according to the content of the above process recipe and via signal line E: the operations of the RF sensor 272, matcher 274, high-frequency power supply 273, RF sensor 282, matcher 284, high-frequency power supply 283. In addition, the CPU 221A is configured to control, according to the content of the above process recipe and via signal line F: the flow adjustment operations of the MFCs 252A to 252C for various process gases, and the opening and closing operations of the valves 253A to 253C and the valve 243A. In addition, the CPU 221A can also control the operations of device structural components other than the above.

[0109] The controller 221 can be configured by installing the above-mentioned program stored in an external storage device (such as magnetic disks like magnetic tapes, floppy disks, and hard disks, optical discs like CDs, DVDs, magneto-optical discs like MOs, semiconductor memories like USB memories, memory cards, etc.) 226 on a computer. The storage device 221C and the external storage device 226 are composed of computer-readable storage media. Hereinafter, these will also be simply collectively referred to as storage media. In the present disclosure, the meaning of "storage medium" includes: only the storage device 221C itself, only the external storage device 226 itself, or both of the above. In addition, the provision of the program to the computer can also be carried out by using communication means such as the Internet, dedicated lines, etc. instead of using the external storage device 226.

[0110] (2) Substrate processing process

[0111] Next, mainly use Figure 11 to describe the substrate processing process of an embodiment of the present disclosure. Figure 11 It is a flowchart showing the substrate processing process of an embodiment of the present disclosure. Regarding the substrate processing process of an embodiment of the present disclosure, for example, it is a process in the manufacturing process of semiconductor devices such as flash memories, and is implemented by the above-mentioned substrate processing apparatus 100. In the following description, the operations of each part constituting the substrate processing apparatus 100 are controlled by the controller 221.

[0112] In addition, although not shown in the figure, on the surface of the wafer 200 processed by the substrate processing process of an embodiment of the present disclosure, grooves having concavo-convex portions with a high aspect ratio are formed in advance. In an embodiment of the present disclosure, for example, a silicon (Si) layer exposed on the inner wall of the groove is subjected to an oxidation process as a process using plasma.

[0113] (Substrate loading process S110)

[0114] First, the above-mentioned wafer 200 is loaded into the processing chamber 201. Specifically, the pedestal lifting mechanism 268 is used to lower the pedestal 217 to the transfer position of the wafer 200. And, the wafer top pin 266 is passed through the through hole 217A of the pedestal 217. As a result, the wafer top pin 266 is in a state where it protrudes from the surface of the pedestal 217 by a predetermined amount.

[0115] Next, open the gate valve 244. Then, using a wafer transfer mechanism (not shown), transfer the wafer 200 from the vacuum transfer chamber adjacent to the processing chamber 201 into the processing chamber 201. The transferred wafer 200 is supported in a horizontal posture on the wafer top pins 266 protruding from the surface of the susceptor 217. After transferring the wafer 200 into the processing chamber 201, retract the wafer transfer mechanism out of the processing chamber 201. Then, close the gate valve 244 to seal the inside of the processing chamber 201. Raise the susceptor 217 using the susceptor lifting mechanism 268, thereby supporting the wafer 200 on the upper surface of the susceptor 217.

[0116] (Heating / Vacuum Exhaust Process S120)

[0117] Next, heat the wafer 200 transferred into the processing chamber 201. The heater 217B is pre-heated, and the wafer 200 is held on the susceptor 217 in which the heater 217B is embedded. By this holding, the wafer 200 is heated to a predetermined value in the range of, for example, 150 to 750 °C. In addition, during the heating of the wafer 200, the inside of the processing chamber 201 is evacuated using the vacuum pump 246 via the gas discharge pipe 231 so that the pressure inside the processing chamber 201 becomes a predetermined value. The vacuum pump 246 operates continuously at least until the substrate unloading process S160 described later is completed.

[0118] (Reactive Gas Supply Process S130)

[0119] Next, start supplying an oxygen-containing gas and a hydrogen-containing gas as reactive gases. Specifically, open the valve 253A and the valve 253B, and start supplying the oxygen-containing gas and the hydrogen-containing gas into the processing chamber 201 while controlling the flow rates by the MFC252A and the MFC252B. At this time, the flow rate of the oxygen-containing gas is set to a predetermined value in the range of, for example, 20 to 2000 sccm. In addition, the flow rate of the hydrogen-containing gas is set to a predetermined value in the range of, for example, 20 to 1000 sccm.

[0120] In addition, adjust the opening degree of the APC valve 242 to control the exhaust inside the processing chamber 201 so that the pressure inside the processing chamber 201 becomes a predetermined pressure in the range of, for example, 1 to 250 Pa. In this way, exhaust the inside of the processing chamber 201 moderately, and continuously supply the oxygen-containing gas and the hydrogen-containing gas until the plasma processing process S140 described later is completed.

[0121] As the oxygen-containing gas, for example, oxygen (O2), nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, ozone (O3) gas, water vapor (H2O gas), carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. can be used. As the oxygen-containing gas, one or more of these can be used.

[0122] In addition, as the hydrogen-containing gas, for example, hydrogen gas (H2), deuterium gas (D2), H2O gas, ammonia gas (NH3), etc. can be used. As the hydrogen-containing gas, one or more of these can be used. In addition, when H2O gas is used as the oxygen-containing gas, it is preferable to use a gas other than H2O gas as the hydrogen-containing gas, and when H2O gas is used as the hydrogen-containing gas, it is preferable to use a gas other than H2O gas as the oxygen-containing gas.

[0123] As the inert gas, for example, nitrogen gas (N2) can be used, and in addition, noble gases such as argon gas (Ar), helium gas (HE), neon gas (NE), xenon gas (XE), etc. can also be used. As the inert gas, one or more of these can be used.

[0124] (Plasma treatment step S140)

[0125] In the plasma treatment step S140, first, a treatment gas is supplied from the gas supply unit, and high-frequency power is supplied from the high-frequency power supply unit 271 to the first resonance coil 212, and high-frequency power is not supplied from the high-frequency power supply unit 281 to the second resonance coil 214.

[0126] Specifically, after the pressure in the processing chamber 201 stabilizes, high-frequency power is started to be applied from the high-frequency power supply 273 to the first resonance coil 212 via the RF sensor 272.

[0127] Thereby, a high-frequency electromagnetic field is formed in the plasma generation space 201A supplied with the oxygen-containing gas and the hydrogen-containing gas. Using this high-frequency electromagnetic field, at the height position corresponding to the electrical midpoint of the first resonance coil 212 in the plasma generation space 201A, a ring-shaped ICP310 with the highest plasma density is excited. The plasma-like oxygen-containing gas and hydrogen-containing gas are dissociated to generate reactive species such as oxygen-containing oxygen groups (oxygen active species), oxygen ions, hydrogen-containing hydrogen groups (hydrogen active species), hydrogen ions, etc.

[0128] Groups and ions generated by inductively coupled plasma are uniformly supplied into the trenches of the wafer 200 held on the susceptor 217 in the substrate processing space 201B. The supplied groups and ions react uniformly with the sidewalls, modifying the surface layer (e.g., Si layer) into an oxide layer with good step coverage (e.g., Si oxide layer).

[0129] After that, when a predetermined processing time, for example, 10 to 300 seconds, has elapsed, the output of power from the high-frequency power supply 273 is stopped.

[0130] Next, the processing gas is supplied from the gas supply unit, and high-frequency power is supplied from the high-frequency power supply unit 281 to the second resonant coil 214. The high-frequency power supply unit 271 stops supplying high frequency power to the first resonant coil 212. Specifically, after the pressure in the processing chamber 201 stabilizes, high-frequency power is supplied from the high-frequency power supply unit 283 to the second resonant coil 214 via the RF sensor 282.

[0131] This generates a high-frequency electromagnetic field within plasma generation space 201A, where oxygen-containing gas and hydrogen-containing gas are supplied. This high-frequency electromagnetic field excites annular ICP 312, which has the highest plasma density, at a height corresponding to the electrical midpoint of second resonant coil 214 in plasma generation space 201A. The plasma-like oxygen-containing gas and hydrogen-containing gas dissociate, generating reactive species such as oxygen-containing oxygen radicals (oxygen active species), oxygen ions, hydrogen-containing hydrogen radicals (hydrogen active species), and hydrogen ions.

[0132] Radicals generated by the inductively coupled plasma, radicals whose lifetimes have been extended during this process by the inductively coupled plasma generated by the first resonant coil 212, and unaccelerated ions are uniformly supplied into the grooves of the wafer 200 held on the susceptor 217 in the substrate processing space 201B. The supplied radicals and ions react uniformly with the sidewalls, converting the surface layer (e.g., Si layer) into an oxide layer (e.g., Si oxide layer) with good step coverage.

[0133] After that, after a predetermined processing time, for example, 10 to 300 seconds, the power output from the high-frequency power supply 283 is stopped, and the plasma discharge in the processing chamber 201 is stopped.

[0134] Furthermore, the valve 253A and the valve 253B are closed to stop the supply of the oxygen-containing gas and the hydrogen-containing gas into the processing chamber 201. The plasma processing step S140 is completed through the above process.

[0135] (Vacuum Exhaust Step S150)

[0136] After the supply of the oxygen-containing gas and the hydrogen-containing gas is stopped, the interior of the processing chamber 201 is evacuated via the gas exhaust pipe 231. Thus, the oxygen-containing gas and the hydrogen-containing gas in the processing chamber 201, as well as exhaust gases generated by the reaction between these gases, are exhausted to the outside of the processing chamber 201. Thereafter, the opening of the APC valve 242 is adjusted to bring the pressure in the processing chamber 201 to the same level as that of the vacuum transfer chamber (not shown) adjacent to the processing chamber 201. The vacuum transfer chamber is the destination from which the wafers 200 are carried out.

[0137] (Substrate Unloading Step S160)

[0138] After the pressure in the processing chamber 201 reaches a predetermined value, the susceptor 217 is lowered to the transfer position of the wafer 200, and the wafer 200 is supported on the top pins 266 on the wafer. Then, the gate valve 244 is opened, and the wafer 200 is carried out of the processing chamber 201 by the wafer transfer mechanism.

[0139] Through the above process, the substrate processing step of one embodiment of the present disclosure is completed.

[0140] <Other embodiments>

[0141] The above describes various typical embodiments and variations of the present disclosure. The present disclosure is not limited to these embodiments and can be appropriately combined and applied.

[0142] In the above embodiment, the second arrangement area SA is formed on the side closer to the susceptor 217 than the first arrangement area FA in the vertical direction of the apparatus. However, the present disclosure is not limited to this. For example, the second arrangement area SA may also be formed on the side farther from the susceptor 217 than the first arrangement area FA in the vertical direction of the apparatus.

[0143] In addition, in the above embodiment, as Figure 8 shown, the first arrangement area FA and the second arrangement area SA are formed on the outer periphery of the processing container 203. However, the present disclosure is not limited to this. For example Figure 12 as shown, a third arrangement area TA may also be formed on the opposite side of the first arrangement area FA across the second arrangement area SA. The third arrangement area TA is alternately arranged with the conductor 212A of the first resonance coil 212 and the conductor 214A of the second resonance coil 214 in the axial direction (vertical direction). At this time, by grounding both ends of the first resonance coil 212, a doubling of the wavelength of the supplied high-frequency power can be formed, and thus a sine curve of the voltage can be formed. Thereby, it is easy to control the peak of the voltage distribution of the first resonance coil 212.

[0144] In addition, in the above embodiment, the axial length of the coil portion of the first resonance coil 212 is different from the axial length of the coil portion of the second resonance coil 214. However, the present disclosure is not limited to this. It may also be that the axial length of the coil portion of the first resonance coil 212 is the same as the axial length of the coil portion of the second resonance coil 214. Here, for example, the first resonance coil 212 and the second resonance coil 214 may be configured as a whole to overlap, or the lower part of the first resonance coil 212 may be overlapped with the upper part of the second resonance coil 214 for configuration. In addition, when the axial length of the coil portion of the first resonance coil 212 is different from the axial length of the coil portion of the second resonance coil 214, a part of the axial length of the coil portion of the first resonance coil 212 may be overlapped with a part of the axial length of the coil portion of the second resonance coil 214 for configuration in the same manner as above.

[0145] In the above method, the processing chamber 201 formed by the processing container 203 has a plasma generation chamber and a substrate processing chamber. That is, the plasma generation chamber and the substrate processing chamber are formed by the same processing container 203. The present disclosure is not limited to this structure. For example, the plasma generation chamber and the substrate processing chamber may be formed by different containers respectively.

[0146] In addition, in the above method, an example of oxidizing the surface of the substrate using plasma is described. However, in addition to this, it can also be applied to nitriding treatment using a nitrogen-containing gas as the processing gas. In addition, not limited to nitriding treatment and oxidizing treatment, it can also be applied to various techniques for processing the substrate using plasma. For example, it can be applied to: modification treatment of the film formed on the surface of the substrate using plasma, doping treatment, reduction treatment of the oxide film, etching treatment of the film, and ashing treatment of the resist, etc.

[0147] In addition, in the above method, two resonance coils are described, but the present disclosure is not limited to this. For example, three or more resonance coils can also be used.

[0148] In addition, although the present disclosure has been described in detail with specific embodiments and modification examples, the present disclosure is not limited to these embodiments and modification examples, and it is obvious to those skilled in the art that various other embodiments can be adopted within the scope of the present disclosure.

[0149] <Preferred Embodiment of the Present Disclosure>

[0150] The preferred solutions of the present disclosure are noted below.

[0151] (Note 1)

[0152] According to one aspect of the present disclosure, there is provided a substrate processing apparatus, which includes:

[0153] A substrate processing chamber for processing a substrate;

[0154] A plasma generation chamber communicating with the substrate processing chamber;

[0155] A gas supply unit capable of supplying gas into the plasma generation chamber;

[0156] A first coil configured to surround the plasma generation chamber and supplied with high-frequency power; and

[0157] A second coil, which is configured to surround the plasma generation chamber, has the same axis as the first coil and a different winding diameter from the first coil, and is supplied with high-frequency power. The peak of the voltage distribution generated by the supply of the high-frequency power does not overlap with the peak of the voltage distribution generated by the first coil.

[0158] (Supplementary Note 2)

[0159] For the substrate processing apparatus according to Supplementary Note 1, preferably,

[0160] In a direction orthogonal to the axis, the peak of the voltage distribution of the second coil does not overlap with the peak of the voltage distribution of the first coil.

[0161] (Supplementary Note 3)

[0162] For the substrate processing apparatus according to Supplementary Note 1 or Supplementary Note 2, preferably,

[0163] In the axial direction, the peak of the voltage distribution of the second coil does not overlap with the peak of the voltage distribution of the first coil.

[0164] (Supplementary Note 4)

[0165] For the substrate processing apparatus according to Supplementary Note 1, preferably,

[0166] On the outer periphery of the plasma generation chamber, there are formed: a first arrangement region, which alternately arranges conductors constituting the first coil and conductors constituting the second coil in the axial direction; and a second arrangement region, which only arranges conductors of the first coil at intervals in the axial direction.

[0167] (Supplementary Note 5)

[0168] For the substrate processing apparatus according to any one of Supplementary Notes 1 to 4, preferably,

[0169] The winding diameter of the first coil is smaller than the winding diameter of the second coil.

[0170] (Supplementary Note 6)

[0171] For the substrate processing apparatus according to Supplementary Note 4 or Supplementary Note 5, preferably,

[0172] The second arrangement region is formed on the side closer to the substrate mounting portion for mounting the substrate than the first arrangement region in the axial direction.

[0173] (Supplementary Note 7)

[0174] For the substrate processing apparatus according to Supplementary Note 6, preferably,

[0175] It has an exhaust portion that can exhaust the gas from the outer periphery of the substrate mounting portion.

[0176] (Supplementary Note 8)

[0177] For the substrate processing apparatus according to any one of Supplementary Notes 4 to 7, preferably,

[0178] In the first arrangement region, the conductors of the first coil and the conductors of the second coil are separated by a distance that does not cause arc discharge.

[0179] In the second arrangement region, the conductors of the first coil are separated by a distance that does not cause arc discharge.

[0180] (Supplementary Note 9)

[0181] For the substrate processing apparatus according to Supplementary Note 4 or Supplementary Note 5, preferably,

[0182] The second arrangement region is formed on the side farther from the substrate mounting portion for mounting the substrate than the first arrangement region in the axial direction.

[0183] (Supplementary Note 10)

[0184] For the substrate processing apparatus according to any one of Supplementary Notes 4 to 7, preferably,

[0185] On the outer periphery of the plasma generation chamber, and on the side opposite to the first arrangement region with the second arrangement region interposed therebetween, a third arrangement region is formed, and the conductors of the first coil and the conductors of the second coil are alternately arranged in the axial direction in the third arrangement region.

[0186] (Supplementary Note 11)

[0187] For the substrate processing apparatus according to any one of Supplementary Notes 1 to 10, preferably,

[0188] The first coil has a pair of grounding connection portions that can be grounded, and the electrical length between the pair of grounding connection portions is a length that is a multiple of the wavelength of the high-frequency power supplied to the first coil.

[0189] (Supplementary Note 12)

[0190] For the substrate processing apparatus according to Supplementary Note 11, preferably,

[0191] The second coil has a pair of grounding connection portions that can be grounded, and the electrical length between the pair of grounding connection portions is a length that is a multiple of the wavelength of the high-frequency power supplied to the second coil.

[0192] (Supplementary Note 13)

[0193] For the substrate processing apparatus according to any one of Supplementary Notes 1 to 12, preferably,

[0194] The waveform adjustment circuit for correcting the electrical length is connected to at least one of the first coil and the second coil such that the electrical length of the first coil is equal to the electrical length of the second coil.

[0195] (Supplementary Note 14)

[0196] In the substrate processing apparatus according to Supplementary Note 13, preferably,

[0197] the waveform adjustment circuit is a variable capacitor.

[0198] (Supplementary Note 15)

[0199] In the substrate processing apparatus according to Supplementary Note 13, preferably,

[0200] the waveform adjustment circuit is a wire made of a conductor.

[0201] (Supplementary Note 16)

[0202] In the substrate processing apparatus according to Supplementary Note 11 or Supplementary Note 12, preferably,

[0203] the ground connection portion located on one axial side of the first coil is configured such that the position in the axial direction is different from the ground connection portion located on one axial side of the second coil.

[0204] (Supplementary Note 17)

[0205] In the substrate processing apparatus according to Supplementary Note 11, Supplementary Note 12 or Supplementary Note 16, preferably,

[0206] the ground connection portion located on the other axial side of the first coil is configured such that the position in the axial direction is different from the ground connection portion located on the other axial side of the second coil.

[0207] (Supplementary Note 18)

[0208] In the apparatus according to any one of Supplementary Notes 1 to 17, preferably,

[0209] the high frequency generated by the power source connected to the first coil is the same frequency as the high frequency generated by the power source connected to the second coil.

[0210] (Supplementary Note 19)

[0211] In the apparatus according to any one of Supplementary Notes 1 to 18, preferably,

[0212] a control unit is provided, and the control unit controls to supply the gas to the plasma generation chamber in a state where high-frequency power is supplied to the first coil and the second coil.

[0213] (Supplementary Note 20)

[0214] According to another aspect of the present disclosure, there is provided a method for manufacturing a semiconductor device, comprising:

[0215] a step of supplying high-frequency power to the first coil and the second coil such that the peak of the voltage distribution generated by the first coil does not overlap with the peak of the voltage distribution generated by the second coil, the first coil being configured to surround a plasma generation chamber, the second coil being configured to surround the plasma generation chamber and having the same axis as the first coil, and having a winding diameter different from that of the first coil; and

[0216] a step of supplying a gas to the plasma generation chamber to process a substrate disposed in a substrate processing chamber communicating with the plasma generation chamber.

[0217] (Supplementary Note 21)

[0218] According to still another aspect of the present disclosure, there is provided a storage medium storing a program that causes a substrate processing apparatus to execute the following steps by a computer:

[0219] a step of supplying high-frequency power to the first coil and the second coil such that the peak of the voltage distribution generated by the first coil does not overlap with the peak of the voltage distribution generated by the second coil, the first coil being configured to surround a plasma generation chamber, the second coil being configured to surround the plasma generation chamber and having the same axis as the first coil, and having a winding diameter different from that of the first coil; and

[0220] a step of supplying a gas to the plasma generation chamber to process a substrate disposed in a substrate processing chamber communicating with the plasma generation chamber.

Claims

1. A substrate processing apparatus, characterized in that, Comprising: A substrate processing chamber for processing a substrate; A plasma generation chamber communicating with the substrate processing chamber; A gas supply unit capable of supplying gas into the plasma generation chamber; A first coil disposed in a first arrangement region surrounding the plasma generation chamber and supplied with high-frequency power; and A second coil disposed in the first arrangement region, having the same axial direction as the first coil and a different winding diameter from the first coil, and supplied with high-frequency power, wherein the peak of the voltage distribution generated by the supply of the high-frequency power does not overlap with the peak of the voltage distribution generated by the first coil, and in the first arrangement region, conductors are alternately arranged with the conductors constituting the first coil in the axial direction.

2. The substrate processing apparatus according to claim 1, wherein: In a direction orthogonal to the axial direction, the peak of the voltage distribution of the second coil does not overlap with the peak of the voltage distribution of the first coil.

3. The substrate processing apparatus according to claim 1, wherein: In the axial direction, the peak of the voltage distribution of the second coil does not overlap with the peak of the voltage distribution of the first coil.

4. The substrate processing apparatus according to claim 1, wherein: A second arrangement region is formed on the outer periphery of the plasma generation chamber, in which only the conductors of the first coil are arranged at intervals in the axial direction.

5. The substrate processing apparatus according to claim 1, wherein: The winding diameter of the first coil is smaller than the winding diameter of the second coil.

6. The substrate processing apparatus according to claim 4, wherein: The second arrangement region is formed on the side closer to the substrate mounting portion for mounting the substrate than the first arrangement region in the axial direction.

7. The substrate processing apparatus according to claim 6, wherein: An exhaust unit is provided, which can exhaust the gas from the outer periphery of the substrate mounting portion.

8. The substrate processing apparatus according to claim 4, wherein: In the first arrangement region, the conductors of the first coil and the conductors of the second coil are separated by a distance that does not cause arc discharge. In the second arrangement region, the conductors of the first coil are separated by a distance that does not cause arc discharge.

9. The substrate processing apparatus according to claim 4, wherein: The second arrangement region is formed on the side farther from the substrate mounting portion for mounting the substrate than the first arrangement region in the axial direction.

10. The substrate processing apparatus according to claim 4, wherein: On the outer periphery of the plasma generation chamber, and on the side opposite to the first arrangement region across the second arrangement region, a third arrangement region is formed, in which the conductors of the first coil and the conductors of the second coil are alternately arranged in the axial direction.

11. The substrate processing apparatus according to claim 1, wherein: The first coil has a pair of grounding connection portions capable of being grounded, and the electrical length between the pair of grounding connection portions is a length that is a multiple of the wavelength of the high-frequency power supplied to the first coil.

12. The substrate processing apparatus according to claim 11, wherein: the second coil has a pair of ground connection portions capable of being grounded, and an electrical length between the pair of ground connection portions is a length that is a multiple of the wavelength of the high-frequency power supplied to the second coil.

13. The substrate processing apparatus according to claim 1, wherein: a waveform adjustment circuit for correcting the electrical length is connected to at least one of the first coil and the second coil such that the electrical length of the first coil is equal to the electrical length of the second coil.

14. The substrate processing apparatus according to claim 13, wherein: the waveform adjustment circuit is a variable capacitor.

15. The substrate processing apparatus according to claim 13, wherein: the waveform adjustment circuit is a wire made of a conductor.

16. The substrate processing apparatus according to claim 11, wherein: the ground connection portion on one axial side of the first coil and the ground connection portion on one axial side of the second coil are different in position in the axial direction.

17. The substrate processing apparatus according to claim 11, wherein: the ground connection portion on the other axial side of the first coil and the ground connection portion on the other axial side of the second coil are different in position in the axial direction.

18. The substrate processing apparatus according to claim 1, wherein: the high frequency generated by the power supply connected to the first coil is the same frequency as the high frequency generated by the power supply connected to the second coil.

19. The substrate processing apparatus according to claim 1, wherein: it includes a control unit configured to be able to control so as to supply the gas to the plasma generation chamber in a state where high-frequency power is supplied to the first coil and the second coil.

20. A method for manufacturing a semiconductor device, characterized in that, It includes: a step of supplying high-frequency power to the first coil and the second coil such that the peak of the voltage distribution generated by the first coil does not overlap with the peak of the voltage distribution generated by the second coil. The first coil is disposed in a first arrangement region surrounding the plasma generation chamber, the second coil is disposed in the first arrangement region and has the same axial direction as the first coil, and has a different winding diameter from the first coil, and in the first arrangement region, conductors are alternately disposed with the conductors constituting the first coil in the axial direction; and a step of supplying a gas to the plasma generation chamber to process a substrate disposed in a substrate processing chamber communicating with the plasma generation chamber.

21. A storage medium, characterized in that, It stores a program, and this program causes a computer to cause the substrate processing apparatus to execute the following steps: A step of supplying high-frequency power to the first coil and the second coil in such a manner that the peak of the voltage distribution generated by the first coil does not overlap with the peak of the voltage distribution generated by the second coil, where the first coil is disposed in a first arrangement region surrounding the plasma generation chamber, the second coil is disposed in the first arrangement region and has the same axis as the first coil, and has a winding diameter different from that of the first coil, and in the first arrangement region, conductors are disposed alternately with the conductors constituting the first coil in the axial direction; And A step of supplying a gas to the plasma generation chamber to process a substrate disposed in a substrate processing chamber communicating with the plasma generation chamber.

22. A substrate processing apparatus, characterized in that, Comprises: A processing chamber having a plasma generation space capable of generating plasma and a substrate processing space capable of processing a substrate; A gas supply unit capable of supplying a gas into the plasma generation space; A first coil disposed in a first arrangement region surrounding the plasma generation space and generating a first voltage distribution; And 23. A substrate processing method, characterized in that, A second coil disposed such that conductors are alternately disposed with the conductors constituting the first coil in the axial direction in the first arrangement region and generating a second voltage distribution that does not overlap with the peak of the first voltage distribution. Has: A process of generating a first voltage distribution by a first coil disposed in a first arrangement region surrounding the plasma generation space, and generating a second voltage distribution that does not overlap with the peak of the first voltage distribution by a second coil disposed such that conductors are alternately disposed with the conductors constituting the first coil in the axial direction in the first arrangement region; and 24. A method for manufacturing a semiconductor device, characterized in that, A process of supplying a gas to the plasma generation space in a processing chamber having the plasma generation space and a substrate processing space to generate plasma, and processing a substrate disposed in the substrate processing space. Has: A process of generating a first voltage distribution by a first coil disposed in a first arrangement region surrounding the plasma generation space, and generating a second voltage distribution that does not overlap with the peak of the first voltage distribution by a second coil disposed such that conductors are alternately disposed with the conductors constituting the first coil in the axial direction in the first arrangement region; and 25. A storage medium, characterized in that, A process of supplying a gas to the plasma generation space in a processing chamber having the plasma generation space and a substrate processing space to generate plasma, and processing a substrate disposed in the substrate processing space. Stores a program, The program causes a substrate processing apparatus to execute the following steps by a computer: A step of generating a first voltage distribution by a first coil disposed in a first arrangement region surrounding the plasma generation space, and generating a second voltage distribution that does not overlap with the peak of the first voltage distribution by a second coil disposed such that conductors are alternately disposed with the conductors constituting the first coil in the axial direction in the first arrangement region; and 26. A substrate processing method, characterized in that, A step of supplying a gas to the plasma generation space in a processing chamber having the plasma generation space and a substrate processing space to generate plasma, and processing a substrate disposed in the substrate processing space. Comprises: A step of supplying high-frequency power to the first coil and the second coil in such a manner that the peak of the voltage distribution generated by the first coil does not overlap with the peak of the voltage distribution generated by the second coil, the first coil being disposed in a first arrangement region surrounding the plasma generation chamber, the second coil being disposed in the first arrangement region and having the same axis as the first coil, and having a winding diameter different from that of the first coil, and having conductors alternately arranged in the axial direction with the conductors constituting the first coil in the first arrangement region; and A step of supplying a gas to the plasma generation chamber to process a substrate disposed in a substrate processing chamber communicating with the plasma generation chamber.

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