Plasma processing apparatus

Abstract

This invention provides a plasma processing apparatus. The plasma processing apparatus includes an antenna made of a conductive material in a wire shape, disposed above a chamber through a dielectric window. The antenna generates plasma within the chamber by radiating RF power into the chamber. The two ends of the line constituting the antenna are open, and power is supplied from a power supply unit to a point near the midpoint of the line. The antenna is grounded near the midpoint of the line, and resonates at half the wavelength of the RF power supplied from the power supply unit. The distances between a first portion of the antenna and the lower surface of the dielectric window, and the distances between a second portion of the antenna and the lower surface of the dielectric window, are longer than the distance between a middle portion of the antenna and the lower surface of the dielectric window. The first portion is a portion of a first distance range from a first end of the antenna, the second portion is a portion of a second distance range from a second end of the antenna, and the middle portion is the portion between the first and second portions of the antenna.

Description

Technical Field

[0001] Various aspects and embodiments of this disclosure relate to a plasma processing apparatus. Background Technology

[0002] As a processing apparatus for performing semiconductor manufacturing processes, plasma processing is known to involve plasmaizing process gases for etching, film deposition, and other similar processes. For example, in monolithic plasma processing apparatuses, it is required to adjust the plasma density distribution along the surface of the substrate to an appropriate distribution depending on the type of processing. Specifically, this can be based on factors such as the structure within the processing container and deviations from subsequent processing on the substrate surface. Therefore, it is not limited to processing the plasma density distribution to make it uniform across the entire surface of the substrate; sometimes, it is intentionally created that the plasma density distribution differs between the central and peripheral portions of the substrate.

[0003] One method for generating plasma in a plasma processing apparatus is to supply high-frequency power to an antenna to induce an electric field within the processing container, thereby exciting the processing gas (see, for example, Patent Document 1 below). This method describes a structure in which an inner coil-shaped antenna, serving as an output high-frequency antenna, and an outer coil-shaped antenna concentric with the inner antenna are provided, such that each antenna resonates at a frequency half the wavelength of the high-frequency wave. According to this plasma processing apparatus, the in-plane distribution of plasma density can be finely adjusted by independently controlling the high-frequency power supplied to each antenna.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2010-258324 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] This disclosure provides a plasma processing apparatus capable of suppressing contamination and improving the uniformity of the process.

[0009] Solution for solving the problem

[0010] One aspect of this disclosure is a plasma processing apparatus comprising: a chamber, a dielectric window, a first antenna, and a first power supply unit. The chamber houses a substrate. The dielectric window forms the upper part of the chamber. The first antenna, formed of a conductive material in a linear shape, is disposed above the chamber through the dielectric window. Furthermore, the first antenna generates plasma within the chamber by radiating RF (Radio Frequency) power into the chamber. The first power supply unit supplies RF power to the first antenna. The first antenna is configured such that both ends of a first line constituting the first antenna are open, power is supplied from the first power supply unit to the midpoint of the first line or the vicinity of the midpoint, the first antenna is grounded near the midpoint of the first line, and the first antenna resonates at half the wavelength of the RF wave power supplied from the first power supply unit. The first antenna has a first portion, a second portion, and a first intermediate portion. The first portion is the portion of the first antenna further from a first position, a first distance away from the center of the first line from a first end, the first end being one of the two ends of the first line. The second part is the portion of the first antenna that is further from the second end than the second position, which is a second distance away from the center of the first line from the second end. The second end is the other end of the two ends of the first line. The first intermediate part is the portion of the first antenna between the first part and the second part. The distance between the first part and the lower surface of the dielectric window, and the distance between the second part and the lower surface of the dielectric window, are longer than the distance between the first intermediate part and the lower surface of the dielectric window.

[0011] The effects of the invention

[0012] According to various aspects and embodiments of this disclosure, it is possible to suppress the generation of contamination and improve the uniformity of processing. Attached Figure Description

[0013] Figure 1 This is a schematic cross-sectional view showing an example of the plasma processing apparatus in the first embodiment.

[0014] Figure 2 This is a schematic perspective view showing an example of the antenna in the first embodiment.

[0015] Figure 3 This is a schematic diagram illustrating an example of the shape of the antenna in the first embodiment.

[0016] Figure 4 It is a diagram used to illustrate the distribution of the intensity of the electric field radiated from the antenna.

[0017] Figure 5A This is a diagram showing an example of the distribution of distances between the antenna and the lower surface of the dielectric window.

[0018] Figure 5BThis is a diagram showing an example of the distribution of the electric field intensity at the lower surface of the dielectric window.

[0019] Figure 6 This is a diagram illustrating an example of the distribution of the distance between the antenna and the lower surface of the dielectric window, as well as the distribution of the electric field intensity at the lower surface of the dielectric window.

[0020] Figure 7 These are schematic diagrams illustrating other examples of antenna shapes.

[0021] Figure 8 These are schematic diagrams illustrating other examples of antenna shapes.

[0022] Figure 9 This is a graph illustrating an example of the amount of pollution generated.

[0023] Figure 10 This is a diagram illustrating an example of the etch rate distribution on a substrate in a comparative example.

[0024] Figure 11 This is a diagram illustrating an example of the distribution of etching rates on the substrate in the first embodiment.

[0025] Figure 12 This is a diagram illustrating an example of the distribution of etching rates near the edges of the substrates in the comparative example and the first embodiment.

[0026] Figure 13 This is a schematic diagram illustrating an example of the shape of the antenna and dielectric window in the second embodiment.

[0027] Figure 14 This is a schematic perspective view showing an example of the shape of the lower surface of the dielectric window in the second embodiment.

[0028] Figure 15 This is a cross-sectional view showing an example of the shape of the protrusion of the dielectric window at the periphery of the antenna when viewed from the direction of the antenna.

[0029] Figure 16 This is a cross-sectional view showing an example of the shape of the protrusion of the dielectric window near the end of the antenna when viewed from a direction orthogonal to the antenna.

[0030] Figure 17 This is a schematic cross-sectional view showing an example of the plasma processing apparatus in the third embodiment.

[0031] Figure 18 This is a schematic perspective view showing an example of the antenna in the third embodiment.

[0032] Figure 19 This is a schematic cross-sectional view showing an example of the plasma processing apparatus in the fourth embodiment.

[0033] Figure 20 This is a schematic diagram illustrating an example of the shape of the first antenna in the fourth embodiment.

[0034] Figure 21 This is a schematic diagram illustrating an example of the shape of the third antenna in the fourth embodiment.

[0035] Figure 22 These are schematic diagrams illustrating other examples of antenna shapes.

[0036] Figure 23A These are schematic diagrams illustrating other examples of antenna shapes.

[0037] Figure 23B These are schematic diagrams illustrating other examples of antenna shapes.

[0038] Figure 23C These are schematic diagrams illustrating other examples of antenna shapes.

[0039] Explanation of reference numerals in the attached figures

[0040] W: Substrate; 10: Plasma processing device; 100: Control device; 11: Chamber; 110: Opening; 111: Gate valve; 12: Partition; 13: Exhaust port; 14: Exhaust pipe; 15: Exhaust device; 21: Base; 212: Flow path; 213: Piping; 214: Gas supply pipe; 22: Base support; 23: Electrostatic chuck; 24: Edge ring; 30: RF power supply; 31: Matching device; 32: Power supply rod; 41: Gas supply pipe; 42 44: Injection section; 45: Gas supply source; 46: MFC; 51: Valve; 52: Shielding box; 53: Dielectric window; 543: Protrusion; 544: Protrusion; 555: Antenna; 54a: First antenna; 54b: Second antenna; 54c: Third antenna; 540: Shape; 541: End portion; 542: End portion; 543: Middle portion; 545: Capacitor; 548: Movable part; 549: Movable part; 61: RF power supply; 62: Matching unit Detailed Implementation

[0041] Hereinafter, embodiments of the disclosed plasma processing apparatus will be described in detail based on the accompanying drawings. Furthermore, the disclosed plasma processing apparatus is not limited to the embodiments described below.

[0042] Furthermore, in antennas utilizing resonance, the electric field intensity radiated from the antenna's ends is higher than that from the center. Therefore, charged particles such as ions are sometimes attracted to the electric field radiated from the antenna's ends, causing sputtering of these attracted particles onto components near the antenna's ends. This can sometimes lead to contamination of components near the antenna's ends.

[0043] Furthermore, near the antenna's end, the intensity distribution of the electric field radiated from the antenna changes drastically, resulting in a disordered distribution. Consequently, the plasma distribution can become disordered, leading to decreased uniformity during substrate processing.

[0044] Therefore, this disclosure provides a technique that can suppress the generation of contamination and improve the uniformity of the process.

[0045] (First Implementation)

[0046] [Structure of plasma processing device 10]

[0047] Figure 1 This is a schematic cross-sectional view showing an example of the plasma processing apparatus 10 in the first embodiment. The plasma processing apparatus 10 includes a chamber 11 formed of a conductive material such as aluminum. An opening 110 for loading and unloading a substrate W is provided on the side of the chamber 11, and the opening 110 can be opened and closed by a gate valve 111. The chamber 11 is grounded.

[0048] A circular plate-shaped base 21, made of a conductive material such as aluminum, is disposed approximately at the center of the bottom surface of the chamber 11, and is used to hold the substrate W, which is the object to be processed. The base 21 also functions as an electrode for attracting ions in the plasma (for generating a bias voltage). The base 21 is supported by a cylindrical base support 22 made of an insulator.

[0049] Additionally, the base 21 is connected to the RF power supply 30 for generating bias voltage via the power supply bar 32 and the matching device 31. RF power at a frequency of, for example, 13 [MHz] is supplied from the RF power supply 30 to the base 21. The frequency and power of the RF power supplied from the RF power supply 30 to the base 21 are controlled by the control device 100, which will be described later.

[0050] An electrostatic chuck 23 for holding the substrate W by electrostatic attraction is provided on the upper surface of the base 21. An edge ring 24 is provided on the outer periphery of the electrostatic chuck 23 in a manner that surrounds the substrate W. The edge ring 24 is sometimes also referred to as a focusing ring.

[0051] Additionally, a flow path 212 for supplying refrigerant, such as cooling water, is formed inside the base 21. The flow path 212 is connected to a cooling unit (not shown) via a pipe 213, from which refrigerant at a regulated temperature is supplied into the flow path 212 via the pipe 213. The temperature of the refrigerant in the cooling unit is controlled by the control device 100, described later.

[0052] A gas supply pipe 214 is provided inside the base 21. The gas supply pipe 214 is used to supply a heat transfer gas, such as He gas, between the electrostatic chuck 23 and the substrate W. The gas supply pipe 214 passes through the electrostatic chuck 23, and the space inside the gas supply pipe 214 is connected to the space between the electrostatic chuck 23 and the substrate W.

[0053] Furthermore, an annular partition 12 is provided between the outer wall of the base support portion 22 and the inner wall of the chamber 11, and a plurality of through holes are formed on the partition 12. Additionally, an exhaust port 13 is formed on the bottom surface of the chamber 11, and the exhaust port 13 is connected to an exhaust device 15 via an exhaust pipe 14. The exhaust device 15 is controlled by a control device 100 described later.

[0054] A circular dielectric window 53, made of a dielectric such as quartz, is provided in the upper part of the chamber 11. The dielectric window 53 constitutes the upper part of the chamber 11. The space above the dielectric window 53 is covered by a cylindrical shielding box 51 made of a conductive material such as aluminum. The shielding box 51 is grounded through the chamber 11. An opening is formed in the center of the shielding box 51 and the dielectric window 53, and a gas supply pipe 41 for supplying processing gas into the chamber 11 is provided in the opening.

[0055] The gas supply source 44 is connected to the gas supply pipe 41 via a valve 46 and an MFC (Mass Flow Controller) 45. In this embodiment, the gas supply source 44 is a supply source of etching processing gas such as CF4 gas or chlorine gas. The MFC 45 controls the flow rate of the processing gas supplied from the gas supply source 44. The valve 46 controls the supply and cut-off of the processing gas, the flow rate of which is controlled by the MFC 45, into the gas supply pipe 41. The processing gas supplied into the gas supply pipe 41 is supplied into the chamber 11 via the injection unit 42.

[0056] An antenna 54 is housed in a space above chamber 11 and surrounded by a dielectric window 53 and a shielding box 51. The antenna 54 is constructed using wiring made of a conductive material. The antenna 54 generates plasma within chamber 11 by radiating RF power into chamber 11. The antenna 54 is an example of a first antenna, and the wiring constituting the antenna 54 is an example of a first wiring. The antenna 54 is positioned around the gas supply pipe 41 in a manner that surrounds the gas supply pipe 41. The wiring constituting the antenna 54 is connected via a matching adapter 62 to an RF power supply 61 for supplying RF power for plasma generation. The RF power supply 61 supplies RF power at a frequency of, for example, 27 MHz to the antenna 54 via the matching adapter 62. Furthermore, the antenna 54 is grounded at a location on the wiring different from the location where the RF power supply 61 is connected via the matching adapter 62. The RF power supply 61 is an example of a first power supply unit.

[0057] In the antenna 54 of this embodiment, both ends of the line constituting the antenna 54 are open, and the RF power supply 61 is connected to the midpoint or vicinity of the line via a matching converter 62, with the vicinity of the midpoint being grounded. Thus, the antenna 54 of this embodiment resonates at half the wavelength of the RF wave power supplied from the RF power supply 61.

[0058] The control device 100 includes a memory such as ROM (Read Only Memory) or RAM (Random Access Memory) and a processor such as a CPU (Central Processing Unit). The memory within the control device 100 stores process data and programs. The processor within the control device 100 reads and executes the programs stored in the memory, thereby controlling the various parts of the plasma processing apparatus 10 based on the process data stored in the memory.

[0059] [Construction of Antenna 54]

[0060] Figure 2 This is a schematic perspective view showing an example of the antenna 54 in the first embodiment. For example, as shown in the diagram... Figure 2 As shown, in this embodiment, the antenna 54 is formed in a generally circular spiral shape with two or more turns. Additionally, for example... Figure 2 As shown, in this embodiment, the area near the end of the lines constituting antenna 54 is shaped such that the lines within a predetermined length range from the end are positioned higher than the plane including lines outside this range. Furthermore, below, the end of the outermost line in the spiral-shaped antenna 54 will be defined as P. out The end of the line located on the inside is defined as P. in End P out As an example of the first end, end P in This is an example of the second end.

[0061] Figure 3 This is a schematic diagram illustrating an example of the shape of the antenna 54 in the first embodiment. Figure 3 The diagram schematically illustrates an example of antenna 54 and dielectric window 53 when they are deployed along the extension direction of the lines constituting antenna 54. In this embodiment, the lower surface of dielectric window 53 (the surface opposite to the surface near antenna 54) is flat.

[0062] exist Figure 3 In the example, from end P outThe position of P1, which is defined as a predetermined distance ΔL1 separated from the line along antenna 54, will be from end P. in The position separated from the line of antenna 54 by a predetermined distance ΔL2 is defined as P2. Additionally, in Figure 3 In the example, end portion 541 is closer to end P than position P1 of the line. out The portion of the side range, the end portion 542 is closer to the end P than the position P2 of the line. in The middle portion 543 is the range of distance ΔL3 from position P1 to position P2. Position P1 is an example of a first position, and position P2 is an example of a second position. Furthermore, distance ΔL1 is an example of a first distance, and distance ΔL2 is an example of a second distance. Additionally, end portion 541 is an example of a first portion, end portion 542 is an example of a second portion, and middle portion 543 is an example of a first middle portion.

[0063] In this embodiment, for example, Figure 3 As shown, the distance Δd1 between the end portion 541 of the antenna 54 and the lower surface of the dielectric window 53 is longer than the distance Δd3 between the middle portion 543 of the antenna 54 and the lower surface of the dielectric window 53. Additionally, for example... Figure 3 As shown, the distance Δd2 between the end portion 542 of the antenna 54 and the lower surface of the dielectric window 53 is longer than the distance Δd3 between the middle portion 543 of the antenna 54 and the lower surface of the dielectric window 53. Distances Δd1 and Δd2 can be the same or different.

[0064] In addition, in this embodiment, for example, Figure 3 As shown, the distance Δd3 between the middle portion 543 of the antenna 54 and the lower surface of the dielectric window 53 is fixed.

[0065] In addition, for example, Figure 3 As shown, in the end portion 541 of the antenna 54 in this embodiment, as the line along the antenna 54 moves from position P1 to end P... out As it moves forward, the distance between the end portion 541 and the lower surface of the dielectric window 53 increases. Similarly, for example, as Figure 3 As shown, in the end portion 542 of the antenna 54 in this embodiment, as the line along the antenna 54 moves from position P2 to end P... in As it moves forward, the distance between the end portion 542 and the lower surface of the dielectric window 53 increases.

[0066] Here, for example, Figure 4 As shown, when an electromagnetic wave with electric field E0 is radiated from antenna 54, the electric flux density D at a location a distance r away from antenna 54 is... rFor example, it can be expressed as in equation (1) below.

[0067]

Number 1

[0068]

[0069] In equation (1) above, α is a proportionality constant.

[0070] With the length of the line constituting the antenna 54 set to 2L, the voltage V(x) generated on the line at a position separated from the center of the line by a distance x is expressed, for example, as shown in equation (2) below.

[0071]

Number 2

[0072]

[0073] In the above formula (2), V m This represents the maximum voltage generated on the line.

[0074] Here, the intensity of the electric field radiated from the line, E0(x), is proportional to the voltage V(x) generated on the line. Furthermore, when the distance between the antenna 54 and the lower surface of the dielectric window 53 is defined as z(x), the intensity of the electric field E(x) at the lower surface of the dielectric window 53 is inversely proportional to the distance z(x). Therefore, the intensity of the electric field E(x) at the lower surface of the dielectric window 53 is expressed, for example, as shown in equation (3) below.

[0075]

Number 3

[0076]

[0077] For example, Figure 5A As shown, when the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53 is fixed along the entire line of the antenna 54, the electric field intensity E(x) at the lower surface of the dielectric window 53 is, for example, as shown in the figure. Figure 5B That's how it's distributed. Figure 5A This is a diagram showing an example of the distribution of the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53. Figure 5B This is a diagram showing an example of the distribution of the electric field intensity E(x) at the lower surface of the dielectric window 53.

[0078] exist Figure 5A In the vertical axis, the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53 is normalized to 1. Additionally, in Figure 5A In the horizontal axis, the distance from the center of the line of antenna 54 with a length of 2L is standardized using length L as a reference. Additionally, in Figure 5BIn the vertical axis, the electric field strength E(x) at each position on the lower surface of the dielectric window 53 corresponding to the line of the antenna 54 is normalized to the electric field strength at the position corresponding to the end of the line of the antenna 54 and the lower surface of the dielectric window 53. Furthermore, in Figure 5B In the horizontal axis, with the position of the lower surface of the dielectric window 53 corresponding to the center of the line of the antenna 54 with length 2L as the reference, the distance of length L to each position of the lower surface of the dielectric window 53 corresponding to the line from the center to the end of the line is standardized.

[0079] Here, the strength of the maximum electric field that does not cause contamination from the lower surface of the dielectric window 53 even if it is sputtered is defined as E. max For example, as shown in equation (4) below, in order to prevent contamination from the lower surface of the dielectric window 53, the electric field strength E(x) at the lower surface of the dielectric window 53 needs to be equal to the electric field strength E. max the following.

[0080]

Number 4

[0081]

[0082] According to equation (4) above, the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53 needs to satisfy equation (5) below.

[0083]

Number 5

[0084]

[0085] For example in Figure 5B Among the distributions of electric field intensity E(x) shown, the maximum electric field intensity E that will not cause contamination from the lower surface of the dielectric window 53 is... max Assuming it is 0.8 times the maximum value of the electric field intensity E(x) at the lower surface of the dielectric window 53. When referring to... Figure 5B At that time, the range of the antenna 54 line is the range from the end of the line to ΔL, where the electric field strength at the lower surface of the dielectric window 53 is more than 0.8 times the maximum value of the electric field strength E(x) at the lower surface of the dielectric window 53. Within this range, if the distance between the antenna 54 and the lower surface of the dielectric window 53 is increased, the electric field strength E(x) at the lower surface of the dielectric window 53 can be suppressed to a lower level.

[0086] Therefore, consider setting the shape of the line from the end of the line to ΔL as a curve that cancels out the increase in the electric field intensity E(x) on the lower surface of the dielectric window 53. That is, consider setting the shape of the end portion 541 such that, for each position of the end portion 541 on the line, the distance z(x) between the end portion 541 and the lower surface of the dielectric window 53 is a distance corresponding to the magnitude of the voltage generated at that position. Similarly, consider setting the shape of the end portion 542 such that, for each position of the end portion 542 on the line, the distance z(x) between the end portion 542 and the lower surface of the dielectric window 53 is a distance corresponding to the magnitude of the voltage generated at that position. Such a curve is represented, for example, by the following equation (6).

[0087]

Number 6

[0088]

[0089] In equation (6) above, when E max When the distance between the antenna 54 and the lower surface of the dielectric window 53 is set to, for example, 0.8 times the maximum value of the electric field strength on the lower surface of the dielectric window 53, the shape of the antenna 54 from the end to ΔL is, for example, as shown in the figure. Figure 6 Like the solid line on the curve above. In this case, for example, as... Figure 6 As shown in the graph below, the electric field intensity E(x) on the lower surface of the dielectric window 53, corresponding to the range from the end of the line to ΔL, is suppressed to 0.8 times the maximum value of the electric field intensity E(x) at the lower surface of the dielectric window 53. Thus, the distance between the end portion 541 and the lower surface of the dielectric window 53 is such that the intensity of the electric field generated on the lower surface of the dielectric window 53 below the end portion 541 due to the voltage generated in the end portion 541 is below a predetermined intensity. Similarly, the distance between the end portion 542 and the lower surface of the dielectric window 53 is such that the intensity of the electric field generated on the lower surface of the dielectric window 53 below the end portion 541 due to the voltage generated in the end portion 542 is below a predetermined intensity.

[0090] In addition, for example, Figure 6 As shown by the dashed line in the curve above, if the shape is longer than the distance z(x) expressed by equation (6), then for example, as shown by the dashed line above the curve. Figure 6As shown by the dashed line in the graph below, the electric field strength E(x) at the lower surface of the dielectric window 53 becomes lower than 0.8 times the maximum value. Furthermore, from the viewpoint of ease of fabrication of the antenna 54, a shape in which the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53 increases at a fixed rate is preferred. Therefore, the antenna 54 of this embodiment adopts a shape in which the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53 increases at a fixed rate. That is, in this embodiment, the end portion 541 increases as the line along the antenna 54 moves from position P1 to end P. out It extends forward and away from the lower surface of the dielectric window 53. Additionally, the end portion 542 extends from position P2 towards end P along the line of the antenna 54. in It extends forward and away from the lower surface of the dielectric window 53.

[0091] Furthermore, if the shapes of the end portions 541 and 542 of the antenna 54 are longer than the shape 540 of the distance z(x) expressed by equation (6), then it can be considered as... Figure 7 That kind of curved shape can also be Figure 8 Such a stepped shape. Furthermore, in any case, the total length of antenna 54 is an integer multiple of 1 / 2 of the wavelength of the supplied RF wave power.

[0092] Furthermore, when the electric field strength E(x) at the lower surface of the dielectric window 53 is too low, it may be difficult to ignite the plasma within the chamber 11. Therefore, it is preferable that the distance z(x) between the antenna 54 and the lower surface of the dielectric window 53 is a distance that allows the electric field strength to be radiated into the chamber 11 within a range that facilitates plasma ignition.

[0093] [Amount of pollution generated]

[0094] Next, an experiment was conducted to generate plasma in chamber 11 and measure the amount of contamination generated in chamber 11. Figure 9 This is a graph illustrating one example of the amount of pollution generated. In Figure 9 The data for a comparative example in which the distance between the antenna 54 and the lower surface of the dielectric window 53 is fixed is also shown. Figure 9 The “1750 / 180[W]” indicates that the RF power supplied to the antenna 54 for generating plasma is 1750[W] and the RF power supplied to the base 21 for generating bias is 180[W].

[0095] In this embodiment, for example, Figure 9As shown, even with arbitrary RF power, the amount of pollution generated is reduced by more than 30% compared to the comparative example. Therefore, in this embodiment, the amount of pollution generated can be reduced compared to the comparative example.

[0096] [Process uniformity]

[0097] Next, an experiment was conducted to measure the distribution of etching rates on substrate W. Figure 10 This is a graph illustrating an example of the etch rate distribution on substrate W in a comparative example. Figure 11 This is a diagram illustrating an example of the etch rate distribution on the substrate W in the first embodiment. In the comparative example, the distance between the antenna 54 and the lower surface of the dielectric window 53 is fixed. Furthermore, the end P of the line of the antenna 54... out The end P is located at approximately -60° relative to the reference direction. in The direction is approximately +60° relative to the reference direction.

[0098] When reference Figure 10 At the end P in Near the edge of the substrate W in the direction of etching, the etching rate locally increases. Furthermore, the deviation of the circumferential etching rate in the region near the edge is greater than the deviation of the circumferential etching rate in the region on the central side of the substrate W.

[0099] On the other hand, when referring to Figure 11 At that time, the deviation of the circumferential etching rate in the central region of the substrate W and the deviation of the circumferential etching rate in the region near the edge were suppressed to the same degree. In addition, no region with a local increase in etching rate was found near the edge of the substrate W.

[0100] Figure 12 This is a diagram illustrating an example of the etch rate distribution near the edge of each substrate W in the comparative example and the first embodiment. Figure 12 The diagram shows the circumferentially normalized etch rate at a position 147 mm from the center of a 300 mm substrate W. Normalization is based on the average of the etch rates in the comparative example and the first embodiment.

[0101] When reference Figure 12 In this embodiment, the deviation in etching rate is reduced compared to that in the comparative example. Specifically, the deviation in etching rate in the first embodiment shows an improvement of approximately 61% compared to that in the comparative example. Therefore, in this embodiment, the uniformity of the processing can be improved compared to the comparative example.

[0102] The first embodiment has been described above. As can be seen from the above description, the plasma processing apparatus of this embodiment includes a chamber 11, a dielectric window 53, an antenna 54, and an RF power supply 61. The chamber 11 houses a substrate W. The dielectric window 53 forms the upper part of the chamber 11. The antenna 54 is formed in a linear shape from a conductive material such as copper and is disposed above the chamber 11 across the dielectric window 53. Furthermore, the antenna 54 generates plasma within the chamber 11 by radiating RF power into the chamber 11. The RF power supply 61 supplies RF power to the antenna 54. The antenna 54 is configured such that both ends of the line constituting the antenna 54 are open, power is supplied from the RF power supply 61 to the midpoint or vicinity of the line, the antenna 54 is grounded near the midpoint of the line, and the antenna 54 resonates at half the wavelength of the RF wave power supplied from the RF power supply 61. The antenna 54 has an end portion 541, an end portion 542, and a middle portion 543. The end portion 541 is the portion of the antenna 54 that is larger than the end portion 542. out The portion of the line moving towards the center is further away from the end P1, which is a distance ΔL1 from the center. out The side portion, the end P out It is one end of the line. End portion 542 is the antenna 54, compared to end P. in The portion of the line moving towards the center is further from the end P2, which is a distance ΔL2 away from the center. in The side portion, the end P in It is the other end of the line. The middle portion 543 is the portion of the antenna 54 between the end portion 541 and the end portion 542. The distance between the end portion 541 and the lower surface of the dielectric window 53, and the distance between the end portion 542 and the lower surface of the dielectric window 53 are longer than the distance between the middle portion 543 and the lower surface of the dielectric window 53. As a result, the generation of contamination can be suppressed and the uniformity of processing can be improved.

[0103] Furthermore, in the first embodiment described above, in the end portion 541, as the line along the antenna 54 moves from position P1 to end P... out As it moves forward, the distance between the end portion 541 and the lower surface of the dielectric window 53 increases. Additionally, in the end portion 542, as the line along the antenna 54 moves from position P2 towards end P... in As the antenna moves forward, the distance between the end portion 542 and the lower surface of the dielectric window 53 increases. This helps to suppress the generation of an excessively large electric field on the lower surface of the dielectric window 53 near the end of the antenna 54.

[0104] Furthermore, in the first embodiment described above, for each position of the end portion 541 on the line, the distance between the end portion 541 and the lower surface of the dielectric window 53 is a distance corresponding to the magnitude of the voltage generated at that position. Similarly, for each position of the end portion 542 on the line, the distance between the end portion 542 and the lower surface of the dielectric window 53 is a distance corresponding to the magnitude of the voltage generated at that position. Therefore, the intensity of the electric field generated on the lower surface of the dielectric window 53 near the end of the antenna 54 can be suppressed to a fixed value or less.

[0105] Furthermore, in the first embodiment described above, the distance between the end portion 541 and the lower surface of the dielectric window 53 is such that the intensity of the electric field generated on the lower surface of the dielectric window 53 below the end portion 541 due to the voltage generated in the end portion 541 is below a predetermined intensity. Similarly, the distance between the end portion 542 and the lower surface of the dielectric window 53 is such that the intensity of the electric field generated on the lower surface of the dielectric window 53 below the end portion 542 due to the voltage generated in the end portion 542 is below a predetermined intensity. Therefore, the intensity of the electric field generated on the lower surface of the dielectric window 53 near the end of the antenna 54 can be suppressed to a fixed value or less.

[0106] Furthermore, in the first embodiment described above, the lower surface of the dielectric window 53 is flat. Additionally, the end portion 541 extends from position P1 to end P along the line of the antenna 54. out It extends forward and away from the lower surface of the dielectric window 53. The end portion 542 extends from position P2 to end P along the line of the antenna 54. in It extends forward and away from the lower surface of the dielectric window 53.

[0107] (Second Implementation)

[0108] In the first embodiment described above, the antenna 54 is configured such that the distance between the vicinity of the end of the antenna 54 and the lower surface of the dielectric window 53 is longer than the distance between the vicinity of the center of the antenna 54 and the lower surface of the dielectric window 53. In contrast, in this embodiment, the dielectric window 53 is configured such that the lower surface of the dielectric window 53 corresponding to the vicinity of the end of the antenna 54 protrudes away from the antenna 54, relative to the antenna 54 which is configured to be included in a plane. Even so, it is possible to make the distance between the vicinity of the end of the antenna 54 and the lower surface of the dielectric window 53 longer than the distance between the vicinity of the center of the antenna 54 and the lower surface of the dielectric window 53.

[0109] Figure 13This is a schematic diagram showing an example of the shape of the antenna 54 and dielectric window 53 in the second embodiment. Figure 14 This is a schematic perspective view showing an example of the shape of the lower surface of the dielectric window 53 in the second embodiment. Figure 13 The diagram schematically illustrates an example of an antenna 54 and dielectric window 53 deployed along the extension direction of the lines constituting the antenna 54. In this embodiment, the antenna 54 is configured as a generally circular spiral shape contained within a plane.

[0110] In this embodiment, for example, Figure 13 and Figure 14 As shown, on the dielectric window 53, a protrusion 531 is formed on the lower surface of the dielectric window 53 corresponding to the end portion 541 of the antenna 54, protruding in a direction away from the antenna 54. The protrusion 531 extends from position P1 toward end P. out The antenna 54 is formed with circuitry. Furthermore, the protrusion 531 is formed such that as it approaches the end P from the position corresponding to the position P1 of the antenna 54... out At the corresponding position, the amount of protrusion increases in the direction away from antenna 54.

[0111] In addition, in this embodiment, for example, Figure 13 and Figure 14 As shown, on the dielectric window 53, a protrusion 532 is formed on the lower surface of the dielectric window 53 corresponding to the end portion 542 of the antenna 54, protruding in a direction away from the antenna 54. The protrusion 532 extends from position P2 toward end P. in The antenna 54 is formed with circuitry. Furthermore, the protrusion 532 is formed such that as it approaches the end P from the position corresponding to position P2 of the antenna 54... in At the corresponding position, the amount of protrusion increases in the direction away from antenna 54.

[0112] In addition, for example, Figure 15 As shown, preferably, the cross-sectional shape of the protrusion 531 along the direction of the end portion 541 is formed such that the distance between the surface of the end portion 541 and the lower surface of the dielectric window 53 is Δd1. Preferably, the cross-sectional shape of the protrusion 532 along the direction of the end portion 542 is also formed such that the distance between the surface of the end portion 542 and the lower surface of the dielectric window 53 is Δd2.

[0113] In addition, for example, Figure 16 As shown, preferably, the end P of the end portion 541 outThe cross-sectional shape of the protrusion 531 in the vicinity is also formed such that the distance between the surface of the end portion 541 and the lower surface of the dielectric window 53 is Δd1. Preferably, the end P of the protrusion 532 at the end portion 542 is... in The cross-sectional shape in the vicinity is also formed such that the distance between the surface of the end portion 542 and the lower surface of the dielectric window 53 is Δd2.

[0114] The second embodiment has been described above. As can be seen from the above description, in this embodiment, the lower surface of the dielectric window 53 below the end portion 541 protrudes in a direction away from the antenna 54, and along the line of the antenna 54 from position P1 downwards towards the end P... out As it moves downwards, the protrusion increases. Additionally, the lower surface of the dielectric window 53 below the end portion 542 protrudes away from the antenna 54, along the line of the antenna 54 from below position P2 towards the end P. in As it moves downwards, the amount of protrusion increases. This helps to suppress contamination and improve the uniformity of the treatment process.

[0115] (Third Implementation)

[0116] In the first embodiment, plasma was generated using antenna 54. In contrast, in this embodiment, two antennas are used to generate plasma. Figure 17 This is a schematic cross-sectional view showing an example of the plasma processing apparatus 10 in the third embodiment. Furthermore, in addition to the aspects described below, Figure 17 In the middle, it is marked with Figure 1 The same structure of the attached figures and Figure 1 The structures in these examples are identical or have the same function, therefore the description is omitted.

[0117] In this embodiment, the antenna 54 has a first antenna 54a and a second antenna 54b. The first antenna 54a and the second antenna 54b are arranged around the gas supply pipe 41 in a manner that surrounds the gas supply pipe 41. The RF power supply 61 is connected to the line constituting the first antenna 54a via a matching adapter 62. In addition, the line constituting the first antenna 54a is grounded at a location on the line that is different from the location where the RF power supply 61 is connected via the matching adapter 62.

[0118] The second antenna 54b is disposed inside the first antenna 54a, that is, between the first antenna 54a and the gas supply pipe 41. In addition, the second antenna 54b can be disposed near the first antenna 54a, or it can be disposed outside the first antenna 54a.

[0119] [Construction of Antenna 54]

[0120] Figure 18This is a schematic perspective view showing an example of the antenna 54 in the third embodiment. The antenna 54 in this embodiment has a first antenna 54a and a second antenna 54b. For example, as... Figure 18 As shown, the first antenna 54a is formed in a roughly circular spiral shape with two or more turns, for example, it is similar to... Figure 2 The antenna 54 of the first embodiment shown has the same construction.

[0121] The second antenna 54b is formed in a loop, and its two ends are connected via a capacitor 545. In this embodiment, the capacitor 545 is a variable capacitor. Alternatively, the capacitor 545 may be a capacitor with a fixed capacitance. The second antenna 54b is inductively coupled to the first antenna 54a, and a current flows in the second antenna 54b in a direction that cancels out the magnetic field generated by the current flowing through the first antenna 54a. The direction and magnitude of the current flowing in the second antenna 54b relative to the current flowing in the first antenna 54a can be controlled by adjusting the capacitance of the capacitor 545. The capacitance of the capacitor 545 is controlled by the control device 100.

[0122] The third embodiment has been described above. As can be seen from the above description, the plasma processing apparatus 10 of this embodiment, in addition to the first antenna 54a of the first embodiment, also includes a second antenna 54b formed in a ring shape, with both ends of the second antenna 54b connected via capacitors. The second antenna 54b is disposed inside or outside the spiral-shaped antenna 54. The first antenna 54a and the second antenna 54b are inductively coupled. Even with this configuration, contamination generation can be suppressed and the uniformity of processing can be improved.

[0123] (Fourth Implementation)

[0124] In the first embodiment, plasma was generated using antenna 54. In contrast, in this embodiment, two antennas are used to generate plasma. Figure 19 This is a schematic cross-sectional view showing an example of the plasma processing apparatus 10 in the fourth embodiment. Furthermore, in addition to the aspects described below, Figure 19 In the middle, it is marked with Figure 1 The same structure of the attached figures and Figure 1 The structures in these examples are identical or have the same function, therefore the description is omitted.

[0125] In this embodiment, the antenna 54 includes a first antenna 54a and a third antenna 54c. The first antenna 54a and the third antenna 54c are disposed around the gas supply pipe 41 in a manner that surrounds the gas supply pipe 41. The first antenna 54a and the third antenna 54c are formed in a generally circular spiral shape with two or more turns, for example, with... Figure 2The antenna 54 of the first embodiment shown has the same construction.

[0126] In the first antenna 54a, both ends of the line constituting the first antenna 54a are open, and the RF power supply 61a is connected to the midpoint or vicinity of the line via a matching converter 62a, the vicinity of which is grounded. Thus, the first antenna 54a resonates at half the wavelength of the RF wave power supplied from the RF power supply 61a.

[0127] In the third antenna 54c, both ends of the circuit constituting the third antenna 54c are open, and the RF power supply 61ca is connected to the midpoint or vicinity of the circuit via a matching converter 62c, with the vicinity of the midpoint being grounded. Thus, the third antenna 54c resonates at half the wavelength of the RF wave power supplied from the RF power supply 61c.

[0128] In this embodiment, the third antenna 54c is disposed inside the first antenna 54a, that is, between the first antenna 54a and the gas supply pipe 41. Furthermore, the third antenna 54c can be disposed near the first antenna 54a, or it can be disposed outside the first antenna 54a, between the first antenna 54a and the dielectric window 53, or above the first antenna 54a. The wiring constituting the first antenna 54a is an example of a first wiring, and the wiring constituting the third antenna 54c is an example of a second wiring.

[0129] Figure 20 This is a schematic diagram illustrating an example of the shape of the first antenna 54a in the fourth embodiment. Figure 20 The diagram schematically illustrates an example of a first antenna 54a and a dielectric window 53 deployed along the extension direction of the line constituting the first antenna 54a. In this embodiment, the lower surface of the dielectric window 53 (the surface opposite to the surface near the first antenna 54a) is flat.

[0130] exist Figure 20 In the example, from end P aout The distance ΔL was separated along the line of the first antenna 54a by a predetermined distance. a1 The position is defined as P a1 It will be from end P ain The distance ΔL was separated along the line of the first antenna 54a by a predetermined distance. a2 The position is defined as P a2 Additionally, in Figure 20 In the example, end portion 541a is compared to position P. a1 More towards the end P aout The portion of the line within the side range, end portion 542a is compared to position P. a2 More towards the end Pain The section of the line extending to the side. Additionally, the middle section 543a is the section of the line from position P. a1 To position P a2 Distance ΔL a3 The portion of the range. End P aout This is an example of the first end, end P. ain This is an example of the second end. Position P a1 This is an example of the first position, position P. a2 This is an example of the second position. Additionally, the distance ΔL... a1 This is an example of the first distance, distance ΔL a2 This is an example of the second distance. In addition, the end portion 541a is an example of the first portion, the end portion 542a is an example of the second portion, and the middle portion 543a is an example of the first middle portion.

[0131] In this embodiment, for example, Figure 20 As shown, the distance Δd between the end portion 541a of the first antenna 54a and the lower surface of the dielectric window 53 is... a1 The distance Δd between the middle portion 543a of the first antenna 54a and the lower surface of the dielectric window 53. a3 Long. Also, for example, Figure 20 As shown, the distance Δd between the end portion 542a of the first antenna 54a and the lower surface of the dielectric window 53 is... a2 The distance Δd between the middle portion 543a of the first antenna 54a and the lower surface of the dielectric window 53. a3 long.

[0132] Figure 21 This is a schematic diagram illustrating an example of the shape of the third antenna 54c in the fourth embodiment. Figure 21 The diagram schematically illustrates an example of the third antenna 54c and dielectric window 53 when they are deployed along the extension direction of the lines constituting the third antenna 54c. In this embodiment, the lower surface of the dielectric window 53 (the surface opposite to the surface near the third antenna 54c) is flat.

[0133] exist Figure 21 In the example, from end P cout The predetermined distance ΔL was separated along the line of the third antenna 54c. c1 The position is defined as P c1 It will be from end P cin The predetermined distance ΔL was separated along the line of the third antenna 54c. c2 The position is defined as P c2 Additionally, in Figure 21In the example, the end portion 541c is the line relative position P. c1 More towards the end P cout The portion of the side range, the end portion 542c is the line relative position P. c2 More towards the end P cin The side portion. Additionally, the middle portion 543c is the line from position P. c1 To position P c2 Distance ΔL c3 The portion of the range. End P cout This is an example of a third end, end P. cin This is an example of the fourth end. Position P c1 This is an example of the third position, position P. c2 This is an example of the fourth position. Additionally, the distance ΔL... c1 This is an example of the third distance, distance ΔL c2 This is an example of the fourth distance. In addition, the end portion 541c is an example of the third portion, the end portion 542c is an example of the fourth portion, and the middle portion 543c is an example of the second middle portion.

[0134] In this embodiment, for example, Figure 21 As shown, the distance Δd between the end portion 541c of the third antenna 54c and the lower surface of the dielectric window 53 is... c1 The distance Δd between the middle portion 543c of the third antenna 54c and the lower surface of the dielectric window 53. c3 Long. Also, for example... Figure 21 As shown, the distance Δd between the end portion 542c of the third antenna 54c and the lower surface of the dielectric window 53 is... c2 The distance Δd between the middle portion 543c of the third antenna 54c and the lower surface of the dielectric window 53. c3 long.

[0135] The fourth embodiment has been described above. Even with this configuration, it is possible to suppress contamination and improve the uniformity of the treatment process.

[0136] [other]

[0137] Furthermore, this disclosure is not limited to the above-described embodiments, and various modifications can be made within its scope.

[0138] For example, in the antenna 54 of the first embodiment described above, the angle between the middle portion 543 and the end portion 541, and the angle between the middle portion 543 and the end portion 542, are fixed, but the disclosed technology is not limited thereto. For example, Figure 22As shown, alternatively, a movable part 548 can be provided at position P1 on the antenna 54, allowing the angle between the middle part 543 and the end part 541 to be changed. Similarly, a movable part 549 can be provided at position P2 on the antenna 54, allowing the angle between the middle part 543 and the end part 542 to be changed. That is, the end part 541 can rotate about position P1 away from the dielectric window 53, and the end part 542 can rotate about position P2 away from the dielectric window 53.

[0139] Therefore, for example, during plasma ignition, the angles between the intermediate portion 543 and the end portion 541, and between the intermediate portion 543 and the end portion 542, can be increased to shorten the distance between the end portions 541 and 542 and the lower surface of the dielectric window 53. Alternatively, after plasma ignition, the angles between the intermediate portion 543 and the end portion 541, and between the intermediate portion 543 and the end portion 542, can be decreased to lengthen the distance between the end portions 541 and 542 and the lower surface of the dielectric window 53. This makes plasma ignition easier and suppresses contamination.

[0140] Alternatively, after igniting the plasma, the angle between the intermediate portion 543 and the end portion 541, and the angle between the intermediate portion 543 and the end portion 542, can be changed according to the cumulative plasma treatment time. This can suppress changes in the state of the plasma.

[0141] Alternatively, as shown in Figure 23, multiple movable parts 548 and 549 may be provided on the antenna 54. For example, when igniting the plasma, the shape of the antenna 54 may be set as follows: Figure 23A The shape shown is used to shorten the distance between the end portions 541 and 542 and the lower surface of the dielectric window 53. This makes plasma ignition easier. Furthermore, for example, after plasma ignition, the shape of the antenna 54 is set to... Figure 23B The shape shown increases the distance between the end portions 541 and 542 and the lower surface of the dielectric window 53. This helps to suppress contamination. Furthermore, for example, if the intensity of the electric field radiated into the chamber 11 decreases due to the deposition of reaction byproducts on the lower surface of the dielectric window 53, the shape of the antenna 54 is designed to... Figure 23C That shape shortens the distance between end portions 541 and 542 and the lower surface of the dielectric window 53. This helps to suppress fluctuations in the plasma state.

[0142] In addition, Figures 23A-23CIn the middle, three movable parts 548 are provided at the end portion 541, but the number of movable parts 548 can also be two or more. Furthermore, in Figures 23A-23C In the middle, three movable parts 549 are provided in the end portion 542, but the number of movable parts 549 can also be two or more.

[0143] Furthermore, while the antenna 54 in the first, second, and fourth embodiments described above is formed in a generally circular spiral shape, the disclosed technology is not limited to this. Alternatively, as long as the total length of the antenna 54 is an integer multiple of half the wavelength of the supplied RF wave power, the shape of the antenna 54 can also be ring-shaped (a generally circular shape with only one turn), straight, cross-shaped, radial, sawtooth, or similar shapes.

[0144] Furthermore, the embodiments disclosed herein should be considered illustrative in all respects and not restrictive. In fact, the above embodiments can be embodied in various ways. In addition, the above embodiments can be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

Claims

1. A plasma processing apparatus, comprising: The chamber contains the substrate; A dielectric window, which forms the upper part of the chamber; A first antenna, which is formed into a wire from a conductive material, is disposed above the cavity through the dielectric window. The first antenna generates plasma in the cavity by radiating radio frequency power into the cavity. as well as The first power supply unit supplies radio frequency power to the first antenna. in, The first antenna is configured such that both ends of a first line constituting the first antenna are open, power is supplied from the first power supply unit to the midpoint of the first line or the vicinity of the midpoint, the first antenna is grounded near the midpoint, and the first antenna resonates at half the wavelength of the radio frequency power supplied from the first power supply unit. The first antenna has: The first part is the portion of the first antenna that is closer to the first end than a first position located a first distance away from the center portion of the first line from the first end, the first end being one of the two ends of the first line. The second part is the portion of the first antenna that is further from the second end than the second position of the portion of the first line that is a second distance away from the center of the first line from the second end, and the second end is the other end of the two ends of the first line. The first intermediate portion is the portion of the first antenna between the first portion and the second portion. The distances between the first portion and the lower surface of the dielectric window, and between the second portion and the lower surface of the dielectric window, are longer than the distance between the first intermediate portion and the lower surface of the dielectric window. In the first part and the second part, the distance z(x) between the first antenna and the lower surface of the dielectric window at a distance x separated from the center of the first line along the first line satisfies the following equation: Where α is a proportionality constant, V m The maximum voltage generated on the first line is given by E, where 2L is the length of the first line. max The strength of the electric field generated on the lower surface of the dielectric window that is such that no contamination is generated from the lower surface of the dielectric window.

2. The plasma processing apparatus according to claim 1, characterized in that, in, In the first portion, as the first portion advances along the first line of the first antenna from the first position toward the first end, the distance between the first portion and the lower surface of the dielectric window increases. In the second part, as the second part moves along the first line of the first antenna from the second position toward the second end, the distance between the second part and the lower surface of the dielectric window increases.

3. The plasma processing apparatus according to claim 1 or 2, characterized in that, For each location of the first portion on the first line, the distance between the first portion and the lower surface of the dielectric window is a distance corresponding to the magnitude of the voltage generated at that location. For each location of the second portion on the first line, the distance between the second portion and the lower surface of the dielectric window is a distance corresponding to the magnitude of the voltage generated at that location.

4. The plasma processing apparatus according to claim 1 or 2, characterized in that, The distance between the first portion and the lower surface of the dielectric window is such that the intensity of the electric field generated on the lower surface of the dielectric window below the first portion due to the voltage generated in the first portion is below a predetermined intensity. The distance between the second portion and the lower surface of the dielectric window is such that the intensity of the electric field generated on the lower surface of the dielectric window below the second portion by the voltage generated in the second portion is below a predetermined intensity.

5. The plasma processing apparatus according to claim 1 or 2, characterized in that, The lower surface of the dielectric window is flat. The first portion extends away from the lower surface of the dielectric window as it advances from the first position toward the first end along the first line of the first antenna. The second portion extends away from the lower surface of the dielectric window as it advances from the second position toward the second end along the first line of the first antenna.

6. The plasma processing apparatus according to claim 5, characterized in that, The first part is capable of rotating about the first position as a fulcrum in a direction away from the dielectric window. The second part is capable of rotating about the second position as a fulcrum in a direction away from the dielectric window.

7. The plasma processing apparatus according to claim 1 or 2, characterized in that, The lower surface of the dielectric window below the first portion protrudes away from the first antenna, and the amount of protrusion increases as it advances along the first line from below the first position towards below the first end. The lower surface of the dielectric window below the second portion protrudes away from the first antenna, and the amount of protrusion increases as it moves along the first line from below the second position to below the second end.

8. The plasma processing apparatus according to claim 1 or 2, characterized in that, It also includes a second antenna, which is formed in a loop and its two ends are connected via capacitors. The second antenna is disposed inside or outside the first antenna, which is formed in a loop or spiral shape. The first antenna and the second antenna are inductively coupled.

9. The plasma processing apparatus according to claim 1 or 2, further comprising: The third antenna, which is formed into a ring shape by a conductive material and disposed above the cavity, is disposed inside or outside the first antenna formed into a ring shape, and generates plasma in the cavity by radiating radio frequency power into the cavity. as well as The second power supply unit supplies radio frequency power to the third antenna. The third antenna is configured such that both ends of the second line constituting the third antenna are open, and power is supplied from the second power supply unit to the midpoint or vicinity of the second line. The third antenna is grounded near the midpoint, and the third antenna resonates at half the wavelength of the radio frequency wave power supplied from the second power supply unit. The third antenna has: The third part is the portion of the third antenna that is further from the third end than the third position of the third position towards the center of the second line from the third end, the third end being one of the two ends of the second line. The fourth part is the portion of the third antenna that is further from the fourth end than the third position located a third distance from the center of the second line from the fourth end, the fourth end being the other end of the second line; and The second intermediate portion is the portion of the third antenna between the third portion and the fourth portion. The distance between the third portion and the lower surface of the dielectric window, and the distance between the fourth portion and the lower surface of the dielectric window, are longer than the distance between the second intermediate portion and the lower surface of the dielectric window.

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