Plasma processing apparatus

Abstract

To provide a plasma processing apparatus for generating inductively coupled plasma.SOLUTION: A plasma processing apparatus comprising: a processing container; a substrate holder configured to hold a substrate and accommodated in the processing container; and a plasma generation mechanism configured to generate inductively coupled plasma, wherein the plasma generation mechanism includes a discharge chamber having a loop shape, an antenna including a magnetic core and a coil wound around the magnetic core and configured to generate an induced current in the discharge chamber, and a high frequency power supply configured to supply high frequency power to the coil.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a plasma processing apparatus. [Background technology]

[0002] Patent Document 1 discloses a plasma processing apparatus having a cylindrical processing vessel that can be evacuated, a holding means that holds multiple objects to be processed and is inserted into and removed from the processing vessel, a gas supply means that supplies gas into the processing vessel, and an activation means that activates the gas with plasma, and that performs plasma processing on the objects to be processed, wherein the activation means comprises a plasma generation box arranged along the longitudinal direction of the processing vessel, an inductively coupled electrode arranged along the plasma generation box, and a high-frequency power supply connected to the inductively coupled electrode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-97096 Summary of the Invention [Problem to be solved by the invention]

[0004] In one aspect, the present disclosure provides a plasma processing apparatus for generating an inductively coupled plasma. [Means for solving the problem]

[0005] In order to solve the above problem, according to one aspect, a plasma processing apparatus is provided, comprising: a processing vessel; a substrate holder that holds a substrate and is housed within the processing vessel; and a plasma generation mechanism that generates inductively coupled plasma, wherein the plasma generation mechanism has a loop-shaped discharge chamber, a magnetic core, and a coil wound around the magnetic core, an antenna that generates induced current in the discharge chamber, and a high-frequency power supply that supplies high-frequency power to the coil. [Effects of the Invention]

[0006] According to one aspect, a plasma processing apparatus for generating inductively coupled plasma can be provided. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of the configuration of a substrate processing apparatus. [Figure 2] FIG. 2 is a schematic diagram showing an example of the configuration of a plasma generation mechanism according to the first embodiment. [Figure 3] 1 is an example of a horizontal cross-sectional schematic diagram showing an example of the configuration of a plasma generation mechanism according to a first embodiment. [Figure 4] 10 is an example of a graph showing the excitation current of a coil. [Figure 5] FIG. 10 is a schematic diagram showing an example of the configuration of a plasma generation mechanism according to a modified example of the first embodiment. [Figure 6] 10 is an example of a horizontal cross-sectional schematic diagram showing an example of the configuration of a plasma generation mechanism according to a modified example of the first embodiment. FIG. [Figure 7] FIG. 10 is a schematic diagram showing an example of the configuration of a plasma generation mechanism according to another modified example of the first embodiment. [Figure 8] FIG. 10 is an example of a horizontal cross-sectional schematic diagram showing an example of the configuration of a plasma generation mechanism according to another modified example of the first embodiment. [Figure 9] FIG. 10 is a schematic diagram showing an example of the configuration of a plasma generation mechanism according to a second embodiment. [Figure 10] FIG. 10 is an example of a horizontal cross-sectional schematic diagram showing an example of the configuration of a plasma generation mechanism according to a second embodiment. [Figure 11]FIG. 10 is a schematic diagram showing an example of the configuration of a plasma generation mechanism according to a third embodiment. [Figure 12] FIG. 10 is an example of a horizontal cross-sectional schematic diagram showing an example of the configuration of a plasma generation mechanism according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant explanations may be omitted.

[0009] [Substrate Processing Apparatus] An example of a substrate processing apparatus (plasma processing apparatus) 100 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing an example of the configuration of the substrate processing apparatus 100. In the following description, the substrate processing apparatus 100 will be described as an example of a film formation apparatus that forms a silicon nitride film on a substrate W by an ALD (Atomic Layer Deposition) process using, for example, plasma of a silicon-containing gas and a nitrogen-containing gas.

[0010] The substrate processing apparatus 100 has a cylindrical processing vessel 1 with a ceiling and an open bottom end. The entire processing vessel 1 is made of, for example, quartz. A ceiling plate 2 made of quartz is provided near the top end of the processing vessel 1, and the area below the ceiling plate 2 is sealed. A cylindrical metal manifold 3 is connected to the opening at the bottom end of the processing vessel 1 via a sealing member 4 such as an O-ring.

[0011] The manifold 3 supports the lower end of the processing vessel 1, and a wafer boat 5 (substrate holder) carrying a large number of semiconductor wafers (hereinafter referred to as "substrates W") (e.g., 25 to 150) stacked as substrates is inserted into the processing vessel 1 from below the manifold 3. In this manner, the processing vessel 1 accommodates the large number of substrates W approximately horizontally with spacing between them in the vertical direction. The wafer boat 5 is made of, for example, quartz. The wafer boat 5 has three rods 6 (two are shown in FIG. 1), and the large number of substrates W are supported by grooves (not shown) formed in the rods 6.

[0012] The wafer boat 5 is placed on a table 8 via a heat-retaining cylinder 7 made of quartz. The table 8 is supported on a rotating shaft 10 that passes through a metal (stainless steel) cover 9 that opens and closes the opening at the bottom end of the manifold 3.

[0013] A magnetic fluid seal 11 is provided at the penetration portion of the rotating shaft 10 to airtightly seal and rotatably support the rotating shaft 10. A seal member 12 is provided between the peripheral portion of the lid 9 and the lower end of the manifold 3 to maintain airtightness inside the processing vessel 1.

[0014] The rotation shaft 10 is attached to the tip of an arm 13 supported by a lifting mechanism (not shown), such as a boat elevator, and the wafer boat 5 and the lid 9 are raised and lowered as a unit to be inserted into and removed from the processing vessel 1. Note that the table 8 may be fixed to the lid 9 side so that the substrates W can be processed without rotating the wafer boat 5.

[0015] The substrate processing apparatus 100 also includes a gas supply unit 20 (processing gas supply unit) that supplies predetermined gases such as a processing gas and a purge gas into the processing chamber 1.

[0016] The gas supply unit 20 includes gas supply pipes 21, 22, and 24. The gas supply pipe 21 is made of, for example, quartz, penetrates the side wall of the manifold 3 inward, bends upward, and extends vertically. A plurality of gas holes 21g are formed at predetermined intervals in the vertical portion of the gas supply pipe 21 over a length corresponding to the wafer support range of the wafer boat 5. Each gas hole 21g discharges gas horizontally. The gas supply pipe 22 is made of, for example, quartz, penetrates the side wall of the manifold 3 inward, bends upward, and extends vertically. A plurality of gas holes 22g are formed at predetermined intervals in the vertical portion of the gas supply pipe 22 over a length corresponding to the wafer support range of the wafer boat 5. Each gas hole 22g discharges gas horizontally. The gas supply pipe 24 is made of, for example, quartz, and is a short quartz pipe that penetrates the side wall of the manifold 3.

[0017] A vertical portion of the gas supply pipe 21 (the vertical portion where the gas holes 21g are formed) is installed inside the processing chamber 1. A processing gas (e.g., a source gas) is supplied to the gas supply pipe 21 from a gas supply source 21a via a gas pipe. A flow rate controller 21b and an on-off valve 21c are installed in the gas pipe. As a result, the processing gas from the gas supply source 21a is supplied into the processing chamber 1 via the gas pipe and the gas supply pipe 21. The processing gas supplied from the gas supply source 21a is, for example, a precursor gas that adsorbs onto the substrate W, such as a silicon-containing gas. The silicon-containing gas is, for example, DCS (dichlorosilane, SiH2Cl2).

[0018] A vertical portion of the gas supply pipe 22 (the vertical portion where the gas holes 22g are formed) is provided in a plasma generation space, which will be described later. A processing gas (e.g., a reactive gas) is supplied to the gas supply pipe 22 from a gas supply source 22a via a gas pipe. The gas pipe is provided with a flow rate controller 22b and an on-off valve 22c. As a result, the processing gas from the gas supply source 22a is supplied to the plasma generation space via the gas pipe and the gas supply pipe 22, and is converted into plasma in the plasma generation space and supplied into the processing vessel 1. The processing gas supplied from the gas supply source 22a is a reactive gas, such as a nitrogen-containing gas, that reacts with a precursor gas adsorbed on the substrate W to form a film (e.g., a silicon nitride film). The nitrogen-containing gas is, for example, NH3.

[0019] The process gas (source gas) supplied from the gas supply source 21a and the process gas (reactive gas) supplied from the gas supply source 22a are not limited to these.

[0020] A purge gas is supplied to the gas supply pipe 24 from a purge gas supply source (not shown) via a gas pipe. A flow rate controller (not shown) and an on-off valve (not shown) are provided in the gas pipe (not shown). As a result, the purge gas from the purge gas supply source is supplied into the processing vessel 1 via the gas pipe and the gas supply pipe 24. The purge gas supplied from the purge gas supply source is an inert gas such as argon (Ar) or nitrogen (N2). Although the case where the purge gas is supplied into the processing vessel 1 via the gas supply pipe 24 has been described, this is not limiting, and the purge gas may be supplied into the processing vessel 1 via either the gas supply pipe 21 or 22.

[0021] A plasma generation mechanism 30 is formed on a part of the sidewall of the processing chamber 1. The plasma generation mechanism 30 generates plasma from the processing gas (reactive gas) supplied from the gas supply source 22a.

[0022] The plasma generation mechanism 30 generates an inductively coupled plasma (ICP) of the processing gas supplied from the gas supply pipe 22, and generates activated species (radicals) of the processing gas.

[0023] The discharge chamber 32 is airtightly welded to the outer wall of the processing vessel 1. The discharge chamber 32 is made of, for example, quartz. The discharge chamber 32 covers an opening 31 formed in the side wall of the processing vessel 1. The opening 31 is elongated in the vertical direction so that it can cover all of the substrates W supported on the wafer boat 5 in the vertical direction. A gas supply pipe 22 for discharging a processing gas is disposed in an inner space defined by the discharge chamber 32 and communicating with the inside of the processing vessel 1, i.e., a plasma generation space. The gas supply pipe 21 for discharging the processing gas is located along the inner wall of the processing vessel 1 outside the plasma generation space, close to the substrates W.

[0024] The plasma generation mechanism 30 generates inductively coupled plasma (ICP) by supplying high frequency power from a high frequency power supply to the antenna. Note that the discharge chamber 32 may be configured to be spaced apart from the substrate W so that the plasma generated in the discharge chamber 32 does not come into contact with the substrate W. Alternatively, a remote plasma configuration may be used in which an ion trap is provided in the opening 31 to supply radicals to the processing vessel 1. Alternatively, a direct plasma configuration may be used in which the plasma generated in the discharge chamber 32 comes into direct contact with the substrate W.

[0025] The details of the plasma generating mechanism 30 will be described later with reference to FIGS.

[0026] An exhaust port 40 (exhaust section) for evacuating the interior of the processing vessel 1 is provided in a sidewall portion of the processing vessel 1 opposite the opening 31. The exhaust port 40 is elongated in the vertical direction to correspond to the wafer boat 5. An exhaust port cover member 41 having a U-shaped cross section is attached to the portion of the processing vessel 1 corresponding to the exhaust port 40. The exhaust port cover member 41 extends upward along the sidewall of the processing vessel 1. An exhaust pipe 42 for evacuating the processing vessel 1 through the exhaust port 40 is connected to the lower part of the exhaust port cover member 41. An exhaust device 44 including a pressure control valve 43, which controls the pressure inside the processing vessel 1, and a vacuum pump, etc., is connected to the exhaust pipe 42. The exhaust device 44 evacuates the interior of the processing vessel 1 through the exhaust pipe 42.

[0027] A cylindrical heating mechanism 50 is provided around the processing vessel 1. The heating mechanism 50 heats the processing vessel 1 and the substrate W therein. The heating mechanism 50 controls the temperature of the processing vessel 1 to a desired temperature. As a result, the substrate W in the processing vessel 1 is heated by radiant heat from the wall surface of the processing vessel 1, etc.

[0028] The substrate processing apparatus 100 also includes a control unit 60. The control unit 60 controls the operation of each unit of the substrate processing apparatus 100, for example, opening and closing the on-off valves 21c and 22c to start and stop the supply of each gas, controlling the gas flow rate using the flow rate controllers 21b and 22b, and controlling exhaust using the exhaust device 44. The control unit 60 also controls the on-off of high-frequency power using the high-frequency power supply 38 of the plasma generation mechanism 30 (see FIG. 2, etc., described later), and controls the temperature of the processing chamber 1 and the substrate W therein using the heating mechanism 50.

[0029] The control unit 60 may be, for example, a computer. A computer program for controlling the operation of each unit of the substrate processing apparatus 100 is stored in a storage medium. The storage medium may be, for example, a flexible disk, a compact disk, a hard disk, a flash memory, a DVD, or the like.

[0030] [Substrate Processing Process of Substrate Processing Apparatus] Next, an example of the operation of the substrate processing apparatus 100 will be described.

[0031] First, the substrates W are prepared by inserting the wafer boat 5 on which the substrates W are placed into the processing chamber 1.

[0032] Next, the source gas is supplied. Here, the control unit 60 controls the flow rate controller 21b and the on-off valve 21c to supply the source gas from the gas supply source 21a into the processing chamber 1. As a result, the source gas is adsorbed onto the surface of the substrate W, for example.

[0033] Next, an inductively coupled plasma of the reactive gas is generated. Here, the control unit 60 controls the flow rate controller 22b and the on-off valve 22c to supply the reactive gas from the gas supply source 22a into the plasma generation space. The control unit 60 also controls the high-frequency power supply 38 (described later) to supply high-frequency power to a coil provided in the plasma generation mechanism 30. As a result, the reactive gas discharged from the gas supply pipe 22 is converted into plasma in the plasma generation space, and active species such as radicals are supplied into the processing vessel 1 through the opening 31. As a result, for example, the active species (radicals, etc.) of the reactive gas react with the raw material gas adsorbed on the surface of the substrate W, forming a film on the surface of the substrate W.

[0034] A process of supplying a source gas and a process of generating plasma of a reactive gas to process the substrate W constitute one cycle, and by repeating this cycle a predetermined number of times, a film having a desired thickness is formed on the substrate W.

[0035] Here, the substrate processing apparatus 100 using inductively coupled plasma (ICP) can increase the plasma density and supply a large amount of radicals to the substrate W compared to a substrate processing apparatus using capacitively coupled plasma (CCP). Furthermore, in a substrate processing apparatus using capacitively coupled plasma (CCP), ions are drawn toward the electrode, causing them to collide with the wall surface of the discharge chamber 32 and sputter, which may result in wear on the wall surface and generation of particles. In contrast, the substrate processing apparatus 100 using inductively coupled plasma (ICP) can suppress wear on the wall surface and generation of particles.

[0036] However, in order to generate inductively coupled plasma (ICP), a higher current must be passed through the coil to generate a sufficient magnetic field, as compared to the case of capacitively coupled plasma (CCP). Furthermore, as shown in FIG. 1, the processing vessel 1 and the plasma generation mechanism 30 (discharge chamber 32) are housed inside the heating mechanism 50. Therefore, it may be difficult to use a material such as copper, which has good conductivity but low heat resistance, as the electrode material for the coil.

[0037] Furthermore, if a heat-resistant metal (e.g., Inconel (registered trademark)) is used as the electrode material for the coil, its electrical resistivity is higher than that of copper, so most of the input power will be consumed by the heat generated by the coil, and there is a risk that sufficient power will not be able to flow through the coil to generate inductively coupled plasma (ICP).

[0038] First Embodiment Next, a substrate processing apparatus 100 including a plasma generation mechanism 30 according to the first embodiment will be described with reference to Fig. 2 and Fig. 3. Fig. 2 is an example of a schematic diagram showing an example of the configuration of the plasma generation mechanism 30 according to the first embodiment. Fig. 3 is an example of a schematic horizontal cross-sectional view showing an example of the configuration of the plasma generation mechanism 30 according to the first embodiment.

[0039] The plasma generation mechanism 30 according to the first embodiment includes a discharge chamber 32A, a toroidal core 33A, a coil 34A, a power feed line 35, a matching box 36, a coaxial cable 37, and a high-frequency power supply 38.

[0040] The discharge chamber 32A has a looped internal space. In the example shown in FIG. 2, the discharge chamber 32A is looped in the height direction. In other words, the discharge chamber 32A has an internal space that loops around a horizontal axis. For example, the discharge chamber 32A has a first internal space extending in the height direction on the side of the processing vessel 1, a second internal space extending in the height direction on the side away from the processing vessel 1, a third internal space extending horizontally to connect the upper part of the first internal space with the upper part of the second internal space, and a fourth internal space extending horizontally to connect the lower part of the second internal space with the lower part of the first internal space. Thus, the discharge chamber 32A is looped in the order of the first internal space, the third internal space, the second internal space, and the fourth internal space. Note that an opening 31 is provided between the first internal space and the processing vessel 1, and the internal space of the discharge chamber 32A and the internal space of the processing vessel 1 are in communication with each other. 3, the gas supply pipe 22 is preferably disposed in the first internal space where the opening 31 is provided. This makes it possible to make the flow rate distribution of the gas supplied from the opening 31 into the processing vessel 1 more uniform across the height position, compared to when the gas supply pipe 22 is disposed in the second internal space.

[0041] The toroidal core 33A is made of a magnetic material and is formed in an annular (e.g., annular or loop) shape with a through hole in the center. The toroidal core 33A is arranged so that the discharge chamber 32A passes through the through hole. At least one toroidal core 33A may be provided. In addition, the toroidal core 33A is illustrated as being arranged so that the third internal space of the discharge chamber 32A passes through the through hole of the toroidal core 33A and the fourth internal space of the discharge chamber 32A passes through the through hole of the toroidal core 33A, but this is not limiting. The first internal space of the discharge chamber 32A may be arranged to pass through the through hole of the toroidal core 33A, and the second internal space of the discharge chamber 32A may be arranged to pass through the through hole of the toroidal core 33A.

[0042] The coil 34A is wound spirally around the toroidal core 33A. The toroidal core 33A and the coil 34A form an antenna.

[0043] The power supply line 35 electrically connects the coil 34A and the matching box 36. The matching box 36 is a device that performs impedance matching. The coaxial cable 37 electrically connects the matching box 36 and the high-frequency power supply 38. The high-frequency power supply 38 is connected to the antenna (coil 34A) via the coaxial cable 37, the matching box 36, and the power supply line 35, and supplies high-frequency power.

[0044] By supplying power to coil 34A, a circular magnetic flux is formed inside toroidal core 33A. Then, a looping induced current (indicated by the solid arrow in FIG. 2) is generated in discharge chamber 32A. This induced current generates an inductively coupled plasma (ICP) in discharge chamber 32A.

[0045] Here, the magnetic core will be explained using Figure 4. Figure 4 is an example of a graph showing the excitation current of a coil. The horizontal axis shows the number of turns in the coil, and the vertical axis shows the simulation results of the excitation current required to generate a certain induced electric field. The solid line shows the results for an air-core coil (Air), and the dashed line shows the results for a coil with a magnetic core (Core).

[0046] As shown in Figure 4, the excitation current is significantly reduced in the case of a coil with a magnetic core (Core) compared to the case of an air-core coil (Air). This means that by using a magnetic core (toroidal core 33A), it is possible to generate inductively coupled plasma (ICP) by using a material for coil 34A that has higher heat resistance and electrical resistivity than copper.

[0047] The material of the magnetic core (toroidal core 33A) can be any of Mn-Zn ferrite, Ni-Zn ferrite, Fe powder core, etc. Mn-Zn ferrite and Ni-Zn ferrite can be used at temperatures of 300°C or less, and Fe powder core can be used at temperatures of 700°C or less.

[0048] Furthermore, the use of the annular toroidal core 33A can suppress leakage of magnetic flux, which in turn can reduce the excitation current required to generate a certain induced electric field.

[0049] The coil may be made of a heat-resistant metal, such as a nickel alloy (specifically, Inconel (registered trademark), Hastelloy (registered trademark), Nimonic (registered trademark), or the like).

[0050] <Modification of the first embodiment> Next, a substrate processing apparatus 100 including a plasma generation mechanism 30 according to a modification of the first embodiment will be described with reference to Fig. 5 and Fig. 6. Fig. 5 is an example of a schematic diagram showing an example of the configuration of the plasma generation mechanism 30 according to the modification of the first embodiment. Fig. 6 is an example of a schematic horizontal cross-sectional view showing an example of the configuration of the plasma generation mechanism 30 according to the modification of the first embodiment.

[0051] The plasma generation mechanism 30 according to the modification of the first embodiment includes a discharge chamber 32B, a toroidal core 33B, a coil 34B, a power feed line 35, a matching box 36, a coaxial cable 37, and a high-frequency power supply 38. The plasma generation mechanism 30 according to the modification of the first embodiment (see FIGS. 5 and 6) differs from the plasma generation mechanism 30 according to the first embodiment (see FIGS. 2 and 3) in the direction of the looped induced current.

[0052] The discharge chamber 32B has a looped internal space. In the example shown in FIG. 5, the discharge chamber 32B is looped in the height direction. In other words, the discharge chamber 32B has an internal space that loops around a horizontal axis. For example, the discharge chamber 32B has a first internal space extending in the height direction on the near side of the paper surface of FIG. 5, a second internal space extending in the height direction on the far side of the paper surface of FIG. 5, a third internal space extending horizontally to connect the upper part of the first internal space with the upper part of the second internal space, and a fourth internal space extending horizontally to connect the lower part of the second internal space with the lower part of the first internal space. As a result, the discharge chamber 32B is looped in the order of the first internal space, the third internal space, the second internal space, and the fourth internal space. Note that an opening 31 is provided between the first internal space and the second internal space and the processing vessel 1, so that the internal space of the discharge chamber 32B communicates with the internal space of the processing vessel 1. As shown in FIG. 6, the gas supply pipe 22 is preferably arranged in the first internal space and the second internal space.

[0053] The toroidal core 33B is made of a magnetic material and is formed in an annular (e.g., annular or loop) shape with a through hole at the center. The toroidal core 33B is arranged so that the discharge chamber 32B passes through the through hole. At least one toroidal core 33B may be provided. In addition, the toroidal core 33B is illustrated as being arranged so that the third internal space of the discharge chamber 32B passes through the through hole of the toroidal core 33B and the fourth internal space of the discharge chamber 32B passes through the through hole of the toroidal core 33B, but this is not limiting. The first internal space of the discharge chamber 32B may be arranged to pass through the through hole of the toroidal core 33B, or the second internal space of the discharge chamber 32B may be arranged to pass through the through hole of the toroidal core 33B.

[0054] The coil 34B is wound spirally around the toroidal core 33B. The toroidal core 33B and the coil 34B form an antenna.

[0055] The power supply line 35 electrically connects the coil 34B and the matching box 36. The matching box 36 is a device that performs impedance matching. The coaxial cable 37 electrically connects the matching box 36 and the high-frequency power supply 38. The high-frequency power supply 38 is connected to the antenna (coil 34B) via the coaxial cable 37, the matching box 36, and the power supply line 35, and supplies high-frequency power.

[0056] By supplying power to coil 34B, a circular magnetic flux is formed inside toroidal core 33B. Then, a looping induced current (indicated by a solid arrow in FIG. 5) is generated in discharge chamber 32B. This induced current generates an inductively coupled plasma (ICP) in discharge chamber 32B.

[0057] <Another Modification of the First Embodiment> Next, a substrate processing apparatus 100 including a plasma generation mechanism 30 according to a modification of the first embodiment will be described with reference to FIGS. 7 and 8. FIG. 7 is an example of a schematic diagram showing a configuration example of a plasma generation mechanism 30 according to another modification of the first embodiment. FIG. 8 is an example of a schematic horizontal cross-sectional view showing a configuration example of a plasma generation mechanism 30 according to another modification of the first embodiment. Note that the plasma generation mechanism 30 according to another modification of the first embodiment (see FIGS. 7 and 8) has a different direction of the looped induced current compared to the plasma generation mechanism 30 according to the first embodiment (see FIGS. 2 and 3).

[0058] The plasma generation mechanism 30 according to another modification of the first embodiment includes a discharge chamber 32C, a toroidal core 33C, a coil 34C, a power feed line 35, a matching box 36, a coaxial cable 37, and a high-frequency power supply 38.

[0059] The discharge chamber 32C has a looped internal space. In the example shown in FIG. 7, the discharge chamber 32C has a cylindrical internal space that is looped in the horizontal direction. In other words, the discharge chamber 32C has an internal space that loops around a vertical axis. For example, the discharge chamber 32C has a through-hole that penetrates in the height direction. Furthermore, the gas supply pipe 22 is provided on the opposite side of the through-hole of the discharge chamber 32C from the opening 31. Because the discharge chamber 32C has a cylindrical internal space, providing the gas supply pipe 22 at this position makes it possible to uniformize the flow rate distribution of the gas supplied from the opening 31 into the processing vessel 1 at a vertical position.

[0060] The toroidal core 33C is made of a magnetic material and is formed in an annular (loop) shape. The toroidal core 33C is arranged so that the discharge chamber 32C passes through its through-hole. The toroidal core 33C has a first portion extending in the height direction and inserted into the through-hole of the discharge chamber 32C, a second portion extending in the height direction outside the discharge chamber 32C, a third portion connecting the upper portion of the first portion with the upper portion of the second portion, and a fourth portion connecting the lower portion of the first portion with the lower portion of the second portion. As a result, the toroidal core 33C is formed in a loop with the first portion, third portion, second portion, and fourth portion arranged in this order.

[0061] The coil 34C is wound spirally around the toroidal core 33C. Specifically, the coil 34C is wound around the second portion of the toroidal core 33C. The toroidal core 33C and the coil 34C form an antenna.

[0062] The power supply line 35 electrically connects the coil 34C and the matching box 36. The matching box 36 is a device that performs impedance matching. The coaxial cable 37 electrically connects the matching box 36 and the high-frequency power supply 38. The high-frequency power supply 38 is connected to the antenna (coil 34C) via the coaxial cable 37, the matching box 36, and the power supply line 35, and supplies high-frequency power.

[0063] By supplying power to coil 34C, a circular magnetic flux is formed inside toroidal core 33C. A first portion of coil 34C is disposed in the through-hole of discharge chamber 32C, forming a magnetic flux in the height direction. As a result, a looping induced current (indicated by the solid arrow in FIG. 7) is generated in discharge chamber 32C. This induced current generates an inductively coupled plasma (ICP) in discharge chamber 32C.

[0064] Second Embodiment Next, a substrate processing apparatus 100 including a plasma generation mechanism 30 according to a second embodiment will be described with reference to Figs. 9 and 10. Fig. 9 is an example of a schematic diagram showing an example of the configuration of the plasma generation mechanism 30 according to the second embodiment. Fig. 10 is an example of a schematic horizontal cross-sectional view showing an example of the configuration of the plasma generation mechanism 30 according to the second embodiment.

[0065] The plasma generation mechanism 30 according to the second embodiment includes a discharge chamber 32D, a toroidal core 33D, a coil 34D, a power feed line 35, a matching box 36, a coaxial cable 37, and a high-frequency power supply 38.

[0066] In the plasma generation mechanism 30 according to the second embodiment, the discharge chamber 32D is divided in the height direction and multiple discharge chambers 32D are provided. An antenna having a toroidal core 33D and a coil 34D is provided for each discharge chamber 32D. Other configurations are similar to those of the plasma generation mechanism 30 according to the first embodiment (see FIGS. 2 and 3), and redundant explanations will be omitted. In the example of FIG. 8, a single matching box 36 and high-frequency power supply 38 are described as supplying power to each coil 34D, but this is not limiting. Multiple matching boxes 36 and high-frequency power supplies 38 may be provided corresponding to each discharge chamber 32D. A gas supply pipe 22 may be provided corresponding to each discharge chamber 32D.

[0067] This configuration makes it possible to individually adjust the amount of radicals supplied from each discharge chamber 32D to the processing vessel 1. In other words, the distribution of radicals supplied to the processing vessel 1 can be adjusted in the height direction.

[0068] The direction of the induced current formed in each discharge chamber 32D has been described as being the same as in FIGS. 2 and 3, but is not limited to this and may be the same as in FIGS. 5 and 6, or the same as in FIGS.

[0069] <Third embodiment> Next, a substrate processing apparatus 100 including a plasma generation mechanism 30 according to a third embodiment will be described with reference to Figs. 11 and 12. Fig. 11 is an example of a schematic diagram showing an example of the configuration of the plasma generation mechanism 30 according to the third embodiment. Fig. 12 is an example of a horizontal cross-sectional schematic diagram showing an example of the configuration of the plasma generation mechanism 30 according to the third embodiment.

[0070] The plasma generation mechanism 30 according to the third embodiment includes a discharge chamber 32E, a rod core 33E, a coil 34E, a power feed line 35, a matching box 36, a coaxial cable 37, and a high-frequency power supply 38.

[0071] The discharge chamber 32E has a looped internal space. In the example shown in FIG. 11, the discharge chamber 32E has a cylindrical internal space that is looped in the horizontal direction. In other words, the discharge chamber 32E has an internal space that loops around a vertical axis. For example, the discharge chamber 32E has a through-hole that penetrates in the height direction. Furthermore, the gas supply pipe 22 is provided on the opposite side of the through-hole of the discharge chamber 32E from the opening 31. Because the discharge chamber 32E has a cylindrical internal space, providing the gas supply pipe 22 at this position makes it possible to uniformize the flow rate distribution of the gas supplied from the opening 31 into the processing vessel 1 at a vertical position.

[0072] The rod core 33E is made of a magnetic material and is formed in a rod shape, and is disposed in a through hole of the discharge chamber 32E.

[0073] The coil 34E is wound spirally around the rod core 33E. The toroidal core 33E and the coil 34C form an antenna. That is, the rod core 33E around which the coil 34C is wound is disposed in the through-hole of the discharge chamber 32E.

[0074] The power supply line 35 electrically connects the coil 34E and the matching box 36. The matching box 36 is a device that performs impedance matching. The coaxial cable 37 electrically connects the matching box 36 and the high-frequency power supply 38. The high-frequency power supply 38 is connected to the antenna (coil 34E) via the coaxial cable 37, the matching box 36, and the power supply line 35, and supplies high-frequency power.

[0075] By supplying power to coil 34E, a magnetic flux is formed in rod core 33E in the height direction. This generates a looping induced current (indicated by the solid arrow in FIG. 11) in discharge chamber 32E. This induced current generates an inductively coupled plasma (ICP) in discharge chamber 32C.

[0076] The plasma generation mechanism 30 according to the third embodiment can be simplified in structure compared to other embodiments (see FIGS. 2, 3, and 5 to 10) in which the loop-structured core and the loop-structured discharge chamber are inserted into each other's through-holes. Also, the weight of the magnetic core can be reduced compared to the cases shown in FIGS. 7 and 8.

[0077] Furthermore, if a magnetic material with high heat resistance and low magnetic permeability is used as the core material, there is a risk of magnetic flux leakage even in a loop-shaped core. In contrast, according to the plasma generation mechanism 30 of the third embodiment, by placing a rod core 33E with a coil 34E wound directly in the through hole of the discharge chamber 32E, a desired magnetic flux is formed in the through hole of the discharge chamber 32E, and an induced current is formed in the looped discharge chamber 32E, thereby generating plasma.

[0078] The present invention is not limited to the configurations described in the above embodiments, but may be combined with other elements, etc. These aspects can be changed without departing from the spirit of the present invention, and can be appropriately determined depending on the application form. [Explanation of symbols]

[0079] 1. Processing container 5. Wafer boat (substrate holder) 20 Gas supply unit 21, 22 Gas supply pipe 30 Plasma generation mechanism 31 Aperture 32,32A~32E Discharge chamber 33A~33D Toroidal core (magnetic core) 33E Rod core (magnetic core) 34A~34E coil 35 Power supply line 36 Matching box 37 Coaxial Cable 38 High frequency power supply 35 Power supply line 36 Matching box 37 Coaxial Cable 38 High frequency power supply 40 exhaust port 50 Heating mechanism 60 Control Unit 100 Substrate processing apparatus (plasma processing apparatus)

Claims

1. A processing vessel; a substrate holder that holds a substrate and is housed in the processing vessel; a plasma generation mechanism for generating inductively coupled plasma; The plasma generation mechanism includes: a discharge chamber having a loop shape; an antenna having a magnetic core and a coil wound around the magnetic core, for generating an induced current in the discharge chamber; a high frequency power supply that supplies high frequency power to the coil; Plasma processing equipment.

2. The discharge chamber has an interior space that loops around a horizontal axis. The plasma processing apparatus according to claim 1 .

3. the magnetic core is an annular toroidal core, a part of the internal space is inserted into a through hole provided at the center of the toroidal core; The plasma processing apparatus according to claim 2 .

4. The discharge chamber has an interior space that loops around a vertical axis. The plasma processing apparatus according to claim 1 .

5. the magnetic core is an annular toroidal core, a part of the internal space is inserted into a through hole provided at the center of the toroidal core; The plasma processing apparatus according to claim 4 .

6. the magnetic core is a rod-shaped core, The discharge chamber has a through hole penetrating in a height direction, the rod core around which the coil is wound is disposed in the through hole of the discharge chamber; The plasma processing apparatus according to claim 5 .

7. The discharge chamber is Divided into multiple sections in the height direction, The plasma processing apparatus according to claim 1 .

8. The magnetic core is made of any one of Mn-Zn ferrite, Ni-Zn ferrite, and Fe powder core. The plasma processing apparatus according to claim 1 .

9. The coil is Consisting of a nickel alloy, The plasma processing apparatus according to claim 1 .

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