Plasma processing apparatus and dielectric window

Abstract

The plasma processing apparatus includes: a chamber for accommodating a substrate, the chamber including a dielectric window forming an upper portion of the chamber and having a plurality of gas flow paths formed therein; a gas supply unit connected to the plurality of gas flow paths and configured so as to be able to supply a process gas into the chamber; an antenna module disposed above the chamber, having a central region, a first peripheral region surrounding the central region, a second peripheral region surrounding the first peripheral region, and a third peripheral region surrounding the second peripheral region, and having a primary coil disposed in the third peripheral region and a secondary coil disposed in the first peripheral region; and an RF power source capable of supplying RF electric power to at least one of the primary coil and the secondary coil, each of the gas flow paths extending in the radial direction of the dielectric window, and formed such that the distance from the gas supply port to the gas introduction port is equal.

Description

Technical Field

[0001] The present invention relates to a plasma processing apparatus and a dielectric window. Background Art

[0002] There is disclosed a plasma processing apparatus including: a chamber that houses a substrate; a dielectric window that forms an upper portion of the chamber; a gas supply unit that supplies a processing gas into the chamber from an upper portion of the chamber; an antenna that is disposed above the chamber and around the gas supply unit and generates plasma of the processing gas in the chamber by supplying high frequency into the chamber; and an electric power supply unit that supplies high-frequency electric power to the antenna (Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-67503 Summary of the Invention

[0006] Technical Problem to be Solved by the Invention

[0007] The present invention provides a plasma processing apparatus and a dielectric window capable of uniformly supplying a processing gas while suppressing abnormal discharge.

[0008] Technical Means for Solving the Technical Problem

[0009] A plasma processing apparatus according to one aspect of the present invention includes: a chamber that houses a substrate, including a dielectric window that forms an upper portion of the chamber and has a plurality of gas flow paths formed therein; a gas supply unit that is connected to the plurality of gas flow paths and configured to be able to supply a processing gas into the chamber; an antenna assembly that is disposed above the chamber, having a central region, a first peripheral region surrounding the central region, a second peripheral region surrounding the first peripheral region, and a third peripheral region surrounding the second peripheral region, and having a primary coil disposed in the third peripheral region and a secondary coil disposed in the first peripheral region; and an RF power supply configured to be able to supply RF (radio frequency) electric power to at least one of the primary coil and the secondary coil. Each of the plurality of gas flow paths extends in a radial direction of the dielectric window and is formed such that a distance from a gas supply port connected to the gas supply unit to a gas introduction port that introduces the processing gas into the chamber is equal.

[0010] Advantageous Effects of the Invention

[0011] According to the present invention, it is possible to uniformly supply a processing gas while suppressing abnormal discharge. Brief Description of the Drawings

[0012] Figure 1 is a diagram showing an example of a plasma processing system in one embodiment of the present invention.

[0013] Figure 2 It is a schematic perspective view showing an example of the antenna in the present embodiment.

[0014] Figure 3 It is a view showing an example of the arrangement of the inner coil and the outer coil in the present embodiment.

[0015] Figure 4 It is a top view showing an example of the dielectric window in the present embodiment.

[0016] Figure 5 It is a graph showing an example of the relationship between the angle formed by the gas flow path and the inner coil and the acceleration distance of electrons.

[0017] Figure 6 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil.

[0018] Figure 7 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil.

[0019] Figure 8 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil.

[0020] Figure 9 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil.

[0021] Figure 10 It is a schematic perspective view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil.

[0022] Figure 11 It is a cross-sectional view showing an example of the positional relationship when the radial gas flow paths overlap in the thickness direction of the dielectric window.

[0023] Figure 12 It is a cross-sectional view showing an example of the flow path near the gas inlet.

[0024] Figure 13 It is a cross-sectional view showing an example of the flow path near the gas inlet.

[0025] Figure 14 It is a cross-sectional view showing an example of the flow path near the gas inlet.

[0026] Figure 15 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil.

[0027] Figure 16 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil.

[0028] Figure 17 This is a cross-sectional view showing an example of the positional relationship between the gas flow path, the inner coil, and the outer coil.

[0029] Figure 18 This is a cross-sectional view showing an example of the positional relationship between the gas flow path, the inner coil, and the outer coil.

[0030] Figure 19 This is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil.

[0031] Figure 20 This is a cross-sectional view showing an example of the positional relationship between the gas flow path, the inner coil, and the outer coil.

[0032] Figure 21 This is a cross-sectional view showing an example of the positional relationship between the gas flow path, the inner coil, and the outer coil. Detailed Embodiments

[0033] Hereinafter, embodiments of the plasma processing apparatus and the dielectric window of the present invention will be described in detail with reference to the accompanying drawings. In addition, the technology of the present invention is not limited to the following embodiments.

[0034] In an ICP (Inductively Coupled Plasma) type plasma processing apparatus, a dielectric window and a coil-shaped antenna are provided above a chamber to generate an induced electric field in the chamber. Therefore, for introducing a processing gas into the chamber, a gas injector provided at the center of the dielectric window avoiding the antenna or a gas injector provided on the side wall of the chamber is used. However, when these gas injectors are used, the in-plane uniformity of the processing gas is insufficient. In addition, in the case of using a gas shower head, when the diffusion space of the processing gas is directly below the coil of the antenna, abnormal discharge sometimes occurs in the diffusion space. Therefore, it is desired to uniformly supply the processing gas while suppressing abnormal discharge.

[0035] [Structure of Plasma Processing System]

[0036] Hereinafter, a structural example of the plasma processing system will be described. Figure 1 This is a diagram showing an example of the plasma processing system in one embodiment of the present invention. As Figure 1As shown, the plasma processing system includes an inductively coupled plasma processing apparatus 1 and a control unit 2. The inductively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing chamber 10 includes a dielectric window 101. In addition, the plasma processing apparatus 1 includes a substrate support unit 11, a gas introduction unit 16, and an antenna 14. The substrate support unit 11 is disposed inside the plasma processing chamber 10. The antenna 14 is disposed on or above the plasma processing chamber 10 (i.e., on or above the dielectric window 101). The plasma processing chamber 10 has a plasma processing space 10s defined by the dielectric window 101, the side wall 102 of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 has at least one gas supply port for supplying at least one processing gas to the plasma processing space 10s and at least one gas discharge port for discharging gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded.

[0037] The substrate support unit 11 includes a main body portion 111 and a ring assembly 112. The main body portion 111 has a central region 111a for supporting the substrate W and a ring-shaped region 111b for supporting the ring assembly 112. A wafer is an example of the substrate W. The ring-shaped region 111b of the main body portion 111 surrounds the central region 111a of the main body portion 111 in a plan view. The substrate W is disposed on the central region 111a of the main body portion 111, and the ring assembly 112 is disposed on the ring-shaped region 111b of the main body portion 111 so as to surround the substrate W on the central region 111a of the main body portion 111. Accordingly, the central region 111a is also referred to as a substrate support surface for supporting the substrate W, and the ring-shaped region 111b is also referred to as a ring support surface for supporting the ring assembly 112.

[0038] In one embodiment, the main body portion 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a bias electrode. The electrostatic chuck 1111 is disposed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic electrode 1111b disposed within the ceramic member 1111a. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a further has an annular region 111b. In addition, other components surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck and an annular insulating member, may also have the annular region 111b. In this case, the ring assembly 112 can be disposed either on the annular electrostatic chuck or the annular insulating member, or on both the electrostatic chuck 1111 and the annular insulating member. Additionally, at least one RF / DC electrode coupled to an RF (Radio Frequency) power supply 31 and / or a DC (Direct Current) power supply 32 described later can also be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a bias electrode. Furthermore, the conductive member of the base 1110 and the at least one RF / DC electrode can also function as a plurality of bias electrodes. In addition, the electrostatic electrode 1111b can function as a bias electrode. Therefore, the substrate support portion 11 includes at least one bias electrode.

[0039] The ring assembly 112 includes one or more annular members. In one embodiment, the one or more annular members include one or more edge rings and at least one cover ring. The edge ring is formed of a conductive material or an insulating material, and the cover ring is formed of an insulating material.

[0040] Alternatively, the substrate support portion 11 may also include a temperature adjustment module configured to be able to adjust at least one of the electrostatic chuck 1111, the ring assembly 112, and the substrate to a target temperature. The temperature adjustment module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows in the flow path 1110a. In one embodiment, the flow path 1110a is formed within the base 1110, and one or more heaters are disposed within the ceramic member 1111a of the electrostatic chuck 1111. Alternatively, the substrate support portion 11 may also include a heat transfer gas supply portion configured to be able to supply a heat transfer gas to the gap between the back surface of the substrate W and the central region 111a.

[0041] The dielectric window 101 is formed with a plurality of gas flow paths 13 and a gas flow path 15 in the central portion inside. The dielectric window 101 is formed of a dielectric such as ceramics such as quartz and alumina. The plurality of gas flow paths 13 are respectively arranged to extend in the radial direction of the dielectric window 101. That is, the plurality of gas flow paths 13 are respectively formed radially from near the center of the dielectric window 101. A gas introduction portion 16 is formed in the central portion of the dielectric window 101, including each gas supply port 13a of the plurality of gas flow paths 13 and the gas supply port 15a of the gas flow path 15. The plurality of gas flow paths 13 are respectively formed such that the distances from each gas supply port 13a to each gas introduction port 13b leading to the plasma processing chamber 10 are equal. Each gas introduction port 13b is provided at a position that does not overlap with the following outer coil 141 and inner coil 142 of the antenna 14 in the longitudinal direction (for example, along the Figure 1 Z-axis direction). The gas flow path 15 has a gas introduction port 15b on the plasma processing space 10s side. The gas introduction portion 16 is configured to be able to introduce at least one processing gas from the gas supply portion 20 into the plasma processing space 10s via the gas flow paths 13 and 15. In addition, the gas flow path 15 may be omitted.

[0042] The gas supply portion 20 may also include at least one gas source 21, at least one flow controller 22, and at least one diverter 23. In one embodiment, the gas supply portion 20 is configured to be able to supply at least one processing gas from the corresponding gas source 21 to the gas introduction portion 16 via the corresponding flow controller 22 and diverter 23. Each flow controller 22 may also include, for example, a mass flow controller or a pressure-controlled flow controller. The diverter 23 divides the gas flow of the processing gas into the respective gas flow paths 13 and 15. Moreover, the gas supply portion 20 may also include one or more flow modulation devices for modulating or pulsing the flow rate of at least one processing gas. Among them, the diverter 23 may be omitted in the case where the gas flow path 15 is omitted and in the case where the processing gas is uniformly (collectively) supplied to the gas flow paths 13 and 15.

[0043] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to be able to provide at least one RF signal (RF electric power) to at least one bias electrode and the antenna 14. Thereby, it is possible to form plasma from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power supply 31 can function as at least a part of the plasma generation unit, where the plasma generation unit is configured to be able to generate plasma from one or more processing gases in the plasma processing chamber 10. In addition, by supplying a bias RF signal to at least one bias electrode, a bias potential can be generated on the substrate W, and ions in the formed plasma can be introduced into the substrate W.

[0044] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is configured to be coupled to the antenna 14 and generate a source RF signal (source RF electric power) for plasma generation via at least one impedance matching circuit. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may also be configured to generate a plurality of source RF signals having different frequencies. The generated one or more source RF signals are supplied to the antenna 14.

[0045] The second RF generation unit 31b is configured to be coupled to at least one bias electrode via at least one impedance matching circuit and generate a bias RF signal (bias RF electric power). The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generation unit 31b may also be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one bias electrode. Additionally, in each embodiment, at least one of the source RF signal and the bias RF signal may be pulsed.

[0046] Furthermore, the power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a bias DC generation unit 32a. In one embodiment, the bias DC generation unit 32a is connected to at least one bias electrode and configured to generate a bias DC signal. The generated bias DC signal is applied to at least one bias electrode.

[0047] In each embodiment, the bias DC signal may also be pulsed. In this case, a sequence of voltage pulses is applied to at least one bias electrode. The voltage pulses may have a pulse waveform such as rectangular, trapezoidal, triangular, or a combination thereof. In one embodiment, a waveform generation unit for generating a sequence of voltage pulses based on the DC signal is connected between the bias DC generation unit 32a and at least one bias electrode. Thus, the bias DC generation unit 32a and the waveform generation unit constitute a voltage pulse generation unit. The voltage pulses may have a positive polarity or a negative polarity. Additionally, the sequence of voltage pulses may include one or more positive polarity voltage pulses and one or more negative polarity voltage pulses within one period. Furthermore, it may be that, in addition to providing the RF power supply 31, a bias DC generation unit 32a is provided, or a bias DC generation unit 32a may be provided in place of the second RF generation unit 31b.

[0048] The antenna 14 has an outer coil 141 and an inner coil 142 that are coaxially arranged with the gas introduction part 16. The inner coil 142 is arranged around the gas introduction part 16 so as to surround the gas introduction part 16. The outer coil 141 is arranged around the inner coil 142 so as to surround the inner coil 142. The outer coil 141 functions as a primary coil (primary winding) to which the first RF generation unit 31a is connected. In one embodiment, the outer coil 141 is a planar coil and is formed in a substantially circular spiral shape. The inner coil 142 functions as a secondary coil (secondary winding) inductively coupled to the primary coil. That is, the inner coil 142 is not connected to the first RF generation unit 31a. In one embodiment, the inner coil 142 is a planar coil and is formed in a substantially circular ring shape. In one embodiment, the inner coil 142 is connected to a variable capacitor, and the direction and magnitude of the current flowing through the inner coil 142 are controlled by controlling the capacitance of the variable capacitor. The outer coil 141 and the inner coil 142 may be arranged at the same height or at different heights. In one embodiment, the inner coil 142 is arranged at the same height as the outer coil 141.

[0049] The exhaust system 40 can be connected, for example, to a gas discharge port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may also include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s can be regulated by using the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0050] The control unit 2 processes computer-executable commands that cause the plasma processing apparatus 1 to perform the various processes described in the present invention. The control unit 2 can be configured to control the respective elements of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 can be implemented by a computer 2a, for example. The processing unit 2a1 can be configured to perform various control actions by reading a program from the storage unit 2a2 and executing the read program. The program may be pre-stored in the storage unit 2a2 or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and is read and executed by the processing unit 2a1 from the storage unit 2a2. The medium may be various storage media readable by the computer 2a or may be a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a Central Processing Unit (CPU). The storage unit 2a2 may include a Random Access Memory (RAM), a Read Only Memory (ROM), a Hard Disk Drive (HDD), a Solid State Drive (SSD), or a combination thereof. The communication interface 2a3 can also communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0051] [Structure of antenna 14]

[0052] Next, use Figure 2 and Figure 3 to describe the details of the antenna 14. Figure 2 is a schematic perspective view showing an example of the antenna in the present embodiment. Figure 3 is a diagram showing an example of the arrangement of the inner coil and the outer coil in the present embodiment. As Figure 2 and Figure 3As shown, antenna 14 is an example of an antenna assembly disposed above dielectric window 101. When viewed from above, antenna 14 is provided with a central region 101a, a first peripheral region 101b surrounding the central region 101a, a second peripheral region 101c surrounding the first peripheral region 101b, and a third peripheral region 101d surrounding the second peripheral region 101c. In addition, the central region 101a, the first peripheral region 101b, the second peripheral region 101c, and the third peripheral region 101d are set to define the positional relationship between antenna 14 and dielectric window 101. In addition, with respect to the positional relationship with dielectric window 101, each gas inlet 13b is provided at a position longitudinally overlapping with the second peripheral region 101c.

[0053] The outer coil 141 is formed, for example, in a substantially circular spiral shape of two or more turns (two rounds), and is disposed in the third peripheral region 101d such that the central axis of the outer shape of the outer coil 141 coincides with the Z axis. The inner coil 142 is formed, for example, in a substantially circular ring shape, and is disposed in the first peripheral region 101b such that the central axis of the inner coil 142 coincides with the Z axis.

[0054] The outer coil 141 and the inner coil 142 are planar coils, and are disposed above the lower surface of the dielectric window 101, which is the boundary surface with the plasma processing space 10s, in a manner substantially parallel to the surface of the substrate W placed on the electrostatic chuck 1111. In addition, the distance between the outer coil 141 and the lower surface of the dielectric window 101 and the distance between the inner coil 142 and the lower surface of the dielectric window 101 are the same distance. In addition, as another example, the distance between the outer coil 141 and the lower surface of the dielectric window 101 and the distance between the inner coil 142 and the lower surface of the dielectric window 101 may also be different. In addition, the distance between the outer coil 141 and the upper surface of the dielectric window 101 may also be longer than the distance between the inner coil 142 and the upper surface of the dielectric window 101. In addition, the distance between the outer coil 141 and the lower surface of the dielectric window 101 and the distance between the inner coil 142 and the lower surface of the dielectric window 101 may also be configured to be independently changeable by a driving unit (not shown).

[0055] Figure 3 An example of the arrangement of the inner coil 142 and the outer coil 141 when viewed from the direction along the Z axis is shown. The inner coil 142 is disposed in the first peripheral region 101b such that the center of the circle coincides with the Z axis.

[0056] The outer coil 141 includes a line having two open ends. Additionally, a first RF generation unit 31a is connected at or near the midpoint of the line constituting the outer coil 141, and the generation source RF electric power (high-frequency electric power) is supplied from the first RF generation unit 31a to the outer coil 141. Further, the vicinity of the midpoint of the line constituting the outer coil 141 is grounded. The outer coil 141 is configured to resonate at λ / 2 with respect to the wavelength λ of the generation source RF electric power supplied from the first RF generation unit 31a. That is, the outer coil 141 functions as a planar spiral resonator. The voltage generated in the line constituting the outer coil 141 is distributed such that it is minimum near the midpoint of the line and maximum at both ends of the line. Additionally, the current generated in the line constituting the outer coil 141 is distributed such that it is maximum near the midpoint of the line and minimum at both ends of the line. The first RF generation unit 31a that supplies the generation source RF electric power to the outer coil 141 can change the frequency and the electric power. The frequency and the electric power of the generation source RF electric power supplied from the first RF generation unit 31a to the outer coil 141 are controlled by the control unit 2.

[0057] Both ends of the line constituting the inner coil 142 of the inner coil 142 are connected via a capacitor 143. That is, the inner coil 142 includes: a line having two ends and a capacitor 143 connected to the two ends. Additionally, the inner coil 142 is not connected to the first RF generation unit 31a. The capacitor 143 is a variable capacitor. The capacitor 143 can be a capacitor having a fixed capacitance. The inner coil 142 is inductively coupled to the outer coil 141, and a current flows in the inner coil 142 in a direction that cancels the magnetic field generated by the current flowing in the outer coil 141. As a result, the generation source RF electric power from the first RF generation unit 31a is indirectly supplied to the inner coil 142. By controlling the capacitance of the capacitor 143, the direction and magnitude of the current flowing in the inner coil 142 can be controlled with respect to the current flowing in the outer coil 141. The capacitance of the capacitor 143 is controlled by the control unit 2.

[0058] Due to the current flowing through the outer coil 141 and the current flowing through the inner coil 142, a magnetic field in the shape of concentric circles is generated around the outer coil 141 and the inner coil 142. Due to the generated magnetic field, an induced electric field is generated along the outer coil 141 and the inner coil 142 in a direction opposite to the direction of the current flowing through the outer coil 141 and in a direction opposite to the direction of the current flowing through the inner coil 142. Through the induced electric field generated in the plasma processing space 10s due to the magnetic field passing through the dielectric window 101, particularly the induced electric field generated directly below the dielectric window 101, the electrons floating in the plasma processing space 10s are accelerated, and the processing gas supplied to the plasma processing space 10s from the plurality of gas flow paths 13 and the gas flow path 15 of the dielectric window 101 collides with the accelerated electrons, thereby causing the processing gas to be plasmaized. Thus, it is possible to perform a prescribed process such as etching on the substrate W on the electrostatic chuck 1111 using the ions and active species contained in the plasma.

[0059] [Arrangement of the gas flow paths 13 and 15 of the dielectric window 101]

[0060] Next, use Figures 4 to 6 to describe the gas flow paths 13 and 15 in the dielectric window 101. Figure 4 is a top view showing an example of the dielectric window in the present embodiment. In Figure 4 , the positional relationship between the gas flow paths 13 and 15 formed in the dielectric window 101 and the central region 101a, the first peripheral region 101b, the second peripheral region 101c, and the third peripheral region 101d of the antenna 14 is described. In addition, in Figure 4 , for the sake of explanation, the gas flow paths 13 and 15 are shown by solid lines, and the central region 101a, the first peripheral region 101b, the second peripheral region 101c, and the third peripheral region 101d are shown by dashed lines. In addition, in the following description, regarding the positions that overlap longitudinally with the central region 101a, the first peripheral region 101b, the second peripheral region 101c, and the third peripheral region 101d of the antenna 14, the meaning of overlapping longitudinally is sometimes omitted.

[0061] As Figure 4As shown, at positions longitudinally overlapping in the central region 101a, a gas supply port 15a of the gas flow path 15 is disposed at its center. Further, at positions longitudinally overlapping in the central region 101a, gas supply ports 13a of the respective gas flow paths 13 are disposed so as to surround the gas supply port 15a. In the longitudinally overlapping positions of the first peripheral region 101b, the respective gas flow paths 13 are extended along the radial direction of the dielectric window 101. In the first peripheral region 101b, the respective gas flow paths 13 cross the inner coil 142 overlapping longitudinally in a plan view. Here, the crossing includes a case where the angle formed by the respective gas flow paths 13 and the inner coil 142 overlapping longitudinally is within a specified range including substantially orthogonal (90°) with respect to the orthogonal as a reference, for example, a range of 90° ± 45°.

[0062] The induced electric field generated by the current flowing in the inner coil 142 accelerates the electrons in the respective gas flow paths 13. However, when the respective gas flow paths 13 and the inner coil 142 are substantially orthogonal in a plan view, that is, when the angle formed by the respective gas flow paths 13 and the inner coil 142 is 90°, the electrons can only be accelerated over a distance corresponding to the width of the respective gas flow paths 13, and the electrons collide with the inner walls of the respective gas flow paths 13 and disappear. Therefore, abnormal discharge does not occur. However, if the respective gas flow paths 13 and the inner coil 142 are in the same direction in a plan view, the distance over which the electrons can be accelerated becomes longer, and thus abnormal discharge may occur inside the respective gas flow paths 13.

[0063] Figure 5 It is a graph showing an example of the relationship between the angle formed by the gas flow path and the inner coil and the acceleration distance of electrons. Figure 5 The graph 50 shown represents the relationship between the acceleration distance of electrons based on the diameter of the gas flow path 13 and the angle formed by the respective gas flow paths 13 and the inner coil 142. The point 51 on the graph 50 is the point where the angle formed by the respective gas flow paths 13 and the inner coil 142 is 45° or 135°. When the angle formed by the respective gas flow paths 13 and the inner coil 142 is in the range of 45° to 135°, the distance that the accelerated electrons can move is maximally about 1.4 times as large as that in the case where the angle is 90°, as shown by the point 51, and the risk of abnormal discharge is within an allowable range. Therefore, it is preferable that the respective gas flow paths 13 cross the inner coil 142 in a plan view within the range of 90° ± 45° of the angle formed by the respective gas flow paths 13 and the inner coil 142 in a plan view.

[0064] In addition, point 52 on the graph 50 is the point where the angle formed by each gas flow path 13 and the inner coil 142 is 65° or 115°. When the angle formed by each gas flow path 13 and the inner coil 142 is between 65° and 115°, compared with the case where the angle is 90°, the distance that the accelerated electrons can move is about 1.1 times at most as shown by point 52, and the risk of abnormal discharge is within the allowable range. Therefore, it is more preferable that each gas flow path 13 intersects with the inner coil 142 in plan view within the range of 90° ± 25° of the angle formed by each gas flow path 13 and the inner coil 142 in plan view.

[0065] Moreover, point 53 on the graph 50 is the point where the angle formed by each gas flow path 13 and the inner coil 142 is 75° or 105°. When the angle formed by each gas flow path 13 and the inner coil 142 is between 75° and 105°, compared with the case where the angle is 90°, the distance that the accelerated electrons can move is about 1.05 times at most as shown by point 53, and the risk of abnormal discharge is within the allowable range. Therefore, it is more preferable that each gas flow path 13 intersects with the inner coil 142 in plan view within the range of 90° ± 15° of the angle formed by each gas flow path 13 and the inner coil 142 in plan view.

[0066] In Figure 4 's example, in the first peripheral region 101b, each gas flow path 13 branches into two. The gas inlets 13b are arranged at positions longitudinally overlapping in the second peripheral region 101c. In Figure 4 's example, in the second peripheral region 101c, each gas flow path 13 branches into two. That is, in Figure 4 's example, each gas flow path 13 has one gas supply port 13a and four gas inlets 13b, and is formed such that the distances from the gas supply port 13a to each gas inlet 13b are equal. In other words, each gas flow path 13 is formed into a so-called branch flow path (tournament) structure. Therefore, the conductance from the gas supply port 13a to each gas inlet 13b of each gas flow path 13 can be made the same, and uniform gas supply can be performed. In the third peripheral region 101d, the gas flow paths 13 are not formed at positions longitudinally overlapping, and the outer coil 141 is arranged in the third peripheral region 101d.

[0067] Figure 6 is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil. In Figure 6 , regarding the dielectric window 101, it shows a cross-section from the Z-axis to one side in the radial direction. As Figure 6As shown, the gas flow path 13 successively has a longitudinal flow path 13c, a radial (lateral) flow path 13d, a longitudinal flow path 13e, lateral flow paths 13f and 13g, and longitudinal flow paths 13h and 13i starting from the gas supply port 13a side. The flow paths 13f and 13g branch off from the flow path 13e and are formed at a specified angle deviating from the radial direction. The flow path 13f is connected to the flow path 13h and the gas introduction port 13b, and the flow path 13g is connected to the flow path 13i and the gas introduction port 13b. In addition, in Figure 6 the branching in the flow path 13d is omitted. The gas flow path 15 is a longitudinal flow path from the gas supply port 15a to the gas introduction port 15b.

[0068] Here, in the plasma processing chamber 10, an induced electric field is generated along the outer coil 141 and the inner coil 142 in a direction opposite to the direction of the current flowing in the outer coil 141 and in a direction opposite to the direction of the current flowing in the inner coil 142. That is, in Figure 6 since the potential of the induced electric field is in the horizontal direction penetrating the paper surface, abnormal discharge caused by the induced electric field does not occur inside the flow paths 13d, 13f, and 13g which are lateral flow paths and the flow paths 13c, 13e, 13h, and 13i which are longitudinal flow paths. However, sometimes an electric field based on capacitive coupling is generated simultaneously with the generation of the induced electric field from the outer coil 141 and the inner coil 142. In order not to generate abnormal discharge due to the electric field of this capacitive coupling component, the width of each flow path is preferably 5 mm or less, for example.

[0069] In the plasma processing chamber 10, plasma is generated by using the induced electric field generated in the plasma processing space 10s. At this time, high-density plasma is generated directly below the dielectric window 101 when the distance between the outer coil 141 and the inner coil 142 and the plasma processing space 10s is the shortest, as observed from the outer coil 141 and the inner coil 142. That is, there are a high-density plasma generation region P1 and a low-density plasma generation region P2 directly below the dielectric window 101. When there is a gas introduction port 13b near this high-density plasma (plasma generation region P1), the plasma P1 invades the flow paths 13h and 13i from the gas introduction port 13b, and abnormal discharge may occur in the flow paths 13h and 13i.

[0070] In order not to cause such abnormal discharge, it is preferable to space the high-density plasma generation region P1 from the gas introduction port 13b. The distance for spacing the gas introduction port 13b from the high-density plasma generation region P1 depends on the thickness of the dielectric window 101 and the plasma density. For example, when the dielectric window 101 has a thickness of about 50 mm and the plasma density used in the process treatment is 5×10 11 cm -3In the following cases, by setting the gap distance to be about 5 mm or more, abnormal discharge in the gas inlet 13b and the flow paths 13h, 13i can be suppressed, which is based on the inventor's experience.

[0071] Therefore, the distance between the high-density plasma generation region P1 and the gas inlet 13b is preferably 5 mm or more. That is, the distance between the outer coil 141 or the inner coil 142 and the gas inlet 13b is preferably 5 mm or more. Therefore, the radial distance 17 between the gas inlet 13b and the inner coil 142 is, for example, 5 mm or more. In addition, the radial distance 18 between the gas inlet 13b and the outer coil 141 is, for example, 5 mm or more. In addition, the distances 17 and 18 are preferably 10 mm or more. Thereby, the risk of abnormal discharge in the flow paths 13h, 13i can be reduced.

[0072] In addition, in Figure 6 the connection portion between the longitudinal flow path and the lateral flow path is L-shaped, but it is not limited thereto. Figures 7 to 9 is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil. For example, Figure 7 in the dielectric window 101-1 shown, regarding the connection portions of the respective gas flow paths 13, they are connected in the bent flow paths 13j to 13m. Thus, the connection portions of the respective gas flow paths 13 may also be bent.

[0073] In addition, in Figure 6 the longitudinal flow path extends in the vertical direction and the lateral flow path extends in the horizontal direction, but it is not limited thereto. For example, Figure 8 in the dielectric window 101-2 shown, the flow paths 13d-1, 13f-1, 13g-1 are inclined with respect to the vertical direction and the horizontal direction. In addition, the flow paths 13f-1, 13g-1 are connected to the gas inlet 13b-1 in an inclined state. In addition, for example, Figure 9 in the dielectric window 101-3 shown, the flow path 13c-1 is inclined with respect to the vertical direction and is connected to the horizontal flow path 13d-2. The flow path 13c-1 is connected to the gas supply port 13a-1 in an inclined state. In the cases of the dielectric windows 101-2 and 101-3 like this, the risk of abnormal discharge caused by the induced electric field becomes high, but similar to Figure 4 the angle formed by the inner coil 142 and the respective gas flow paths 13 in the top view, if the inclination with respect to the vertical direction and the horizontal direction is in the range of ±45°, the generation of abnormal discharge can be suppressed. In addition, the long longitudinal flow path (for example, the flow path 13a) and the lateral flow path (for example, the flow path 13d) may also be bent.

[0074] Figure 10 is a schematic perspective view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil. AsFigure 10 As shown, the gas flow path 13 is formed such that the gas supply port 13a is located in the central region 101a and the gas introduction port 13b is located in the second peripheral region 101c. The gas flow path 13 extends radially in the first peripheral region 101b where the inner coil 142 is located and is positioned substantially orthogonal to the inner coil 142, so the risk of abnormal discharge is reduced. Since the longitudinal flow path of the gas flow path 15 from the gas supply port 15a to the gas introduction port 15b is located in the central region 101a, the risk of abnormal discharge is reduced. Since the outer coil 141 is located in the third peripheral region 101d, the distance in the radial direction from the gas introduction port 13b is large, and the risk of abnormal discharge can be reduced.

[0075] Next, use Figure 11 To describe the positional relationship when the radial gas flow paths overlap in the thickness direction of the dielectric window. Figure 11 FIG. is a cross-sectional view showing an example of the positional relationship when the radial gas flow paths overlap in the thickness direction of the dielectric window. Figure 11 The shown dielectric window 201 has gas flow paths 202 and 203 that overlap in the thickness direction of the dielectric window 201 instead of the gas flow path 13. The gas flow path 202 sequentially has a longitudinal flow path 202c, a radial flow path 202d, and a longitudinal flow path 202e from the gas supply port 202a to the gas introduction port 202b. The gas flow path 203 sequentially has a longitudinal flow path 203c, a radial flow path 203d, and a longitudinal flow path 203e from the gas supply port 203a to the gas introduction port 203b. The gas flow paths 202 and 203 are, for example, an example of the gas flow paths in an RDC (Radical Distribution Control) structure that divides the process gas into two or more systems and distributes and controls the flow rate for each system. In addition, the gas flow paths 202 and 203 are, for example, an example of the gas flow paths in a PostMix structure that arranges the gas introduction ports in a staggered manner for each gas to shorten the switching time of the process gas.

[0076] The dielectric window 201 has a thickness 204. The thickness 204 can be any thickness in the range of, for example, 15 mm to 50 mm. The dielectric window 201 requires mechanical strength for separating the atmosphere from the vacuum. For example, when using a general ceramic material in a plasma processing apparatus with a substrate W having a diameter of 300 mm, the thickness 204 preferably has a thickness of 15 mm. On the other hand, if the dielectric window is too thick, the distance from the antenna to the inside of the plasma processing chamber 10 becomes far, and the induced electric field inside the plasma processing chamber 10 becomes small, so the plasma generation efficiency decreases. Therefore, the thickness 204 is preferably a thickness of 50 mm or less.

[0077] In addition, the cross-sections of the gas flow paths 202 and 203 can be, for example, circular with any diameter in the range of 2 mm to 5 mm, or quadrilateral with any length in the range of 2 mm to 5 mm for one side. In order to introduce the required flow rate of the processing gas into the plasma processing space 10s, the size of the cross-sections of the gas flow paths 202 and 203 is preferably at least 2 mm or more in diameter. On the other hand, if the cross-section is too large, it may weaken the mechanical strength of the dielectric window and damage the dielectric window. In addition, since abnormal discharge caused by the capacitive coupling component may be generated inside the gas flow paths 202 and 203, the diameter or one side of the gas flow paths 202 and 203 is preferably 5 mm or less.

[0078] In addition, if the intervals between the internal gas flow paths 202 and 203 of the dielectric window 201 are unbalanced (biased to one side), the bending stress becomes weak and it may crack. Therefore, the thickness 205 from the upper surface of the dielectric window 201 to the flow path 202d, the thickness 206 from the flow path 202d to the flow path 203d, and the thickness 207 from the flow path 203d to the lower surface of the dielectric window 201 are preferably equally spaced. Furthermore, in order to ensure strength, the thicknesses 205 to 207 preferably have a thickness of 3 mm or more, for example. In addition, in the case of the dielectric window 101 having a single gas flow path 13 in the thickness direction as described above, the thicknesses from the upper surface and the lower surface of the dielectric window 101 to the flow path 13d are preferably 3 mm or more. And more preferably, the flow path 13d is arranged at the center in the longitudinal direction (thickness direction) of the dielectric window 101. In this way, by providing a thickness between the radial gas flow paths, the breakage of the dielectric windows 101 and 201 can be suppressed.

[0079] [Flow paths near the gas inlet]

[0080] Next, Figures 12 to 14 the flow paths near the gas inlet will be described. In the flow paths 13h and 13i connected to the gas inlet 13b shown in the above Figure 6 , they are shown to have approximately the same thickness as the upstream flow paths 13c to 13g, but in order to further suppress abnormal discharge, they can also be configured as complex flow paths. In addition, the dielectric windows 101, 201, 301, 303, and 305 of the present embodiment are formed into an integral structure by a die casting method without joining multiple components. Therefore, complex flow paths can be formed at low cost.

[0081] Figures 12 to 14 It is a cross-sectional view showing an example of the flow paths near the gas inlet. Figure 12The dielectric window 301 shown has, starting from the gas supply port side, a radial flow path 302a, a longitudinal flow path 302b, a plurality of flow paths 302c thinner than the flow path 302b, and respective gas inlets 302d corresponding to the respective flow paths 302c as the gas flow path 302. In addition, in Figure 12 , the gas flow path 302 on the gas supply port side is omitted. Each flow path 302c is a flow path with a spray structure in the longitudinal or inclined direction. In addition, each gas inlet 302d may also be in the range including each flow path 302c. Since the space inside each flow path 302c is narrow and there are many inclined flow paths, abnormal discharge can be further suppressed. In addition, the flow rate of the processing gas can be controlled by adjusting the number and diameter of the flow paths for each flow path 302c.

[0082] Figure 13 The dielectric window 303 shown has, starting from the gas supply port side, a radial flow path 304a, a longitudinal flow path 304b, and a gas inlet 304c corresponding to the flow path 304b as the gas flow path 304. In addition, in Figure 13 , the gas flow path 304 on the gas supply port side is omitted. Since the flow path 304b is spiral, the space continuous in the longitudinal direction becomes narrow, and abnormal discharge can be further suppressed. In addition, the gas inlet 304c may also be in the range including the flow path 304b.

[0083] Figure 14 The dielectric window 305 shown has, starting from the gas supply port side, a radial flow path 306a, a longitudinal flow path 306b, and a gas inlet 306c corresponding to the flow path 306b as the gas flow path 306. In addition, in Figure 14 , the gas flow path 306 on the gas supply port side is omitted. The flow path 306b has a labyrinth (zigzag) shape, so the space continuous in the longitudinal direction becomes narrow, and abnormal discharge can be further suppressed. In addition, the gas inlet 306c may also be in the range including the flow path 306b. In addition, the spiral shape and the labyrinth shape can be formed by the gasification of a mold such as resin during firing in the die casting method.

[0084] In addition, in the dielectric windows 101, 201, 301, 303, 305 of the present embodiment, a Faraday shield such as metal embedding or a metal film, or a refrigerant flow path for cooling, a heater, etc. can also be formed by the die casting method. And in the case of forming a dielectric window by a structure in which a plurality of components are stacked, alignment is required, but in the present embodiment, since the dielectric windows 101, etc. are formed by integral molding, mechanical errors can be reduced.

[0085] In addition, in the above-described embodiment, a spiral (helical) coil having an open end is used as the antenna 14, but it is not limited thereto. For example, it may be formed as a coil in which an RF generation unit is connected to one end of a circuit and the other end is grounded, a loop-shaped coil, or other shaped antennas.

[0086] In addition, in the above-described embodiment, the antenna 14 has an inner coil 142 and an outer coil 141, and the outer coil 141 is connected to the first RF generation unit 31a, and the inner coil 142 is inductively coupled to the outer coil 141, but it is not limited thereto. For example, the first RF generation unit 31a may be connected to the inner coil 142, and the outer coil 141 may be inductively coupled to the inner coil 1 , or the inner coil 142 and the outer coil 141 may be independently connected to the first RF generation unit 31a. Alternatively, the inner coil 142 and / or the outer coil 141 may be supplied with the generated source RF electric power by being inductively coupled to a coil connected to the first RF generation unit 31a and disposed above the inner coil 142 and / or the outer coil < / END>

[0087] In addition, in the above-described embodiment, the antenna 14 has two coils, an inner coil 142 and an outer coil 141, and a central region 101a, a first peripheral region 101b surrounding the central region 101a, a second peripheral region 101c surrounding the first peripheral region 101b, and a third peripheral region 101d surrounding the second peripheral region 101c are defined. The inner coil 142 is disposed in the first peripheral region 101b, and the outer coil 141 is disposed in the third peripheral region 101d, but it is not limited thereto. Figure 15 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil. As Figure 15 shown, for example, the antenna 14 may be only one inner coil 142. The gas inlets 13b are each provided at a position longitudinally overlapping with the second peripheral region 101c.

[0088] In addition, in the above-described embodiment, the gas inlets 13b are each provided at a position longitudinally overlapping with the second peripheral region 101c, but it is not limited thereto. Hereinafter, using Figures 16 to 20 , variations in the arrangement of each gas flow path 13 with respect to the outer coil 141 and the inner coil 142 will be described. Figure 16 It is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil. It may also be as Figure 16As in the case of the dielectric window 101-4 shown, for example, a fourth surrounding region 101e surrounding the third surrounding region 101d-1 is further set, and the plurality of gas flow paths 13 are respectively extended in the radial direction of the dielectric window 101-4 to the fourth surrounding region 101e. For example, it is extended as shown by the flow path 13d-3. In addition, the gas inlets 13b may be respectively arranged at positions that move from the second surrounding region 101c-1 and overlap with the fourth surrounding region 101e in the longitudinal direction. The gas inlets 13b are respectively arranged at positions spaced 5 mm or more as shown by the distance 18a from the outer coil 141a.

[0089] Figure 17 and Figure 18 is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil and the outer coil. As Figure 17 In the case of the dielectric window 101-5 shown, for example, the gas inlets 13b may be respectively arranged at positions that overlap with the third surrounding region 101d-2 where the outer coil 141b is arranged in the longitudinal direction. The outer coil 141b is formed, for example, into a substantially circular vortex shape with 2 turns (2 rounds) or more, and when the interval between each turn is 10 mm or more, the gas inlets 13b are respectively located in the middle of the interval between each turn, thereby being able to reduce the risk of abnormal discharge. In this case, each gas flow path 13 is extended, for example, as shown by the flow paths 13d-4, 13f-2, and 13g-2. In addition, the intervals between the turns of the outer coil 141b are set such that the radial distances 18b and 18c between the gas inlets 13b and the outer coil 141b are, for example, 5 mm or more. That is, the gas inlets 13b may be respectively arranged at positions that overlap with either the second surrounding region 101c-1 or the third surrounding region 101d-2 in the longitudinal direction. In addition, as Figure 18 In the case of the dielectric window 101-6 shown, the gas inlets 13b may be respectively arranged at positions that overlap with both the second surrounding region 101c-2 and the third surrounding region 101d-3 in the longitudinal direction. In this case, each gas flow path 13 is extended, for example, as shown by the flow paths 13d-5, 13f-3, and 13g-3. In addition, the intervals between the turns of the outer coil 141b are set such that the radial distances 18d and 18e between the gas inlets 13b and the outer coil 141c are, for example, 5 mm or more. And, it is arranged such that the radial distance 17a between the gas inlets 13b and the inner coil 142 is, for example, 5 mm or more. In other words, the gas inlets 13b are respectively arranged at positions spaced 5 mm or more from the outer coils 141b and 141c.

[0090] Figure 19 is a cross-sectional view showing an example of the positional relationship between the gas flow path and the inner coil. Figure 20This is a cross-sectional view showing an example of the positional relationship between the gas flow path, the inner coil, and the outer coil. As Figure 19 shown in the dielectric window 101-7, for example, the gas inlets 13b may each be provided at a position longitudinally overlapping with the first peripheral region 101b-1 where the inner coil 142a is disposed. The inner coil 142a is formed, for example, in a substantially circular spiral shape with two or more turns. When the interval between each turn is 10 mm or more, by positioning the gas inlets 13b at the middle of the interval between each turn, the risk of abnormal discharge can be reduced. In this case, each gas flow path 13 extends, for example, like the flow paths 13d-6, 13f-4, and 13g-4. In addition, the interval between each turn of the inner coil 142a is set such that the radial distances 17b and 17c between the gas inlets 13b and the inner coil 142a are, for example, 5 mm or more. That is, the gas inlets 13b may each be provided at a position longitudinally overlapping with either the first peripheral region 101b-1 or the second peripheral region 101c-3. In addition, as Figure 20 shown in the dielectric window 101-8, the gas inlets 13b are each provided at a position longitudinally overlapping with at least one of the first peripheral region 101b-2 and the second peripheral region 101c-4. In this case, each gas flow path 13 extends, for example, like the flow paths 13d-7, 13f-5, and 13g-5. In addition, the interval between each turn of the inner coil 142b is set such that the radial distances 17c and 17d between the gas inlets 13b and the inner coil 142b are, for example, 5 mm or more. And, it is configured such that the radial distance 18f between the gas inlet 13b and the outer coil 141d is, for example, 5 mm or more. In other words, the gas inlets 13b are each provided at a position spaced 5 mm or more from the inner coils 142a and 142b.

[0091] In addition, in the above-described embodiment, in the dielectric window 201, similar to the gas inlets 13b of the dielectric window 101, the gas inlets 202b are each provided at a position longitudinally overlapping with the second peripheral region 101c, but it is not limited thereto. Figure 21 This is a cross-sectional view showing an example of the positional relationship between the gas flow path, the inner coil, and the outer coil. It may also be like Figure 21Like the dielectric window 201-1 shown, for example, a fourth surrounding region 101e-1 surrounding the third surrounding region 101d-5 is further set, and at least one of the plurality of gas flow paths 202 and 203 extends in the radial direction of the dielectric window 201-1 to the fourth surrounding region 101e-1. For example, it extends as shown by the flow path 202d-1. In addition, in the example of the dielectric window 201-1, since the gas inlet 203b is arranged in the second surrounding region 101c-5, the flow path 203d-1 extends to the second surrounding region 101c-5. Further, at least one of the gas inlets 202b and 203b may be arranged at a position that moves from the second surrounding region 101c-5 and overlaps the fourth surrounding region 101e-1 in the longitudinal direction. The gas inlets 202b and 203b are arranged at positions spaced 5 mm or more apart from the outer coil 141e as shown by distances 18g and 18h. In addition, the gas inlet 203b is arranged at a position spaced 5 mm or more apart from the inner coil 142c as shown by distance 17e, where the inner coil 142c is arranged at a position that overlaps the first surrounding region 101b-3 in the longitudinal direction.

[0092] As described above, according to the present embodiment, the plasma processing apparatus 1 includes a chamber (plasma processing chamber 10), a gas supply unit 20, an antenna assembly (antenna 14), and an RF power supply (first RF generation unit 31a). The chamber is a chamber for accommodating the substrate W and includes a dielectric window 101 that forms the upper part of the chamber and in which a plurality of gas flow paths 13 are formed inside. The gas supply unit 20 is connected to the plurality of gas flow paths 13 and is configured to be able to supply a processing gas into the chamber. The antenna assembly is arranged above the chamber, and a central region 101a, a first surrounding region 101b surrounding the central region 101a, a second surrounding region 101c surrounding the first surrounding region 101b, and a third surrounding region 101d surrounding the second surrounding region 101c are set. It has a primary coil (outer coil 141) arranged in the third surrounding region 101d and a secondary coil (inner coil 142) arranged in the first surrounding region 101b. The RF power supply is configured to be able to supply RF electric power to at least one of the primary coil and the secondary coil. The plurality of gas flow paths 13 each extend in the radial direction of the dielectric window 101 and are formed such that the distances from the gas supply port 13a connected to the gas supply unit 20 to the gas inlet 13b for introducing the processing gas into the chamber are equal. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0093] In addition, according to the present embodiment, the gas inlets 13b are each arranged at a position that overlaps the second surrounding region 101c in the longitudinal direction. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0094] In addition, according to the present embodiment, the primary coil is formed in a substantially circular vortex shape, and the gas inlets 13b are each provided at a position longitudinally overlapping with either the second peripheral region 101c or the third peripheral region 101d. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0095] In addition, according to the present embodiment, the gas supply ports 13a are each provided at a position longitudinally overlapping with the central region 101a. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0096] In addition, according to the present embodiment, the plurality of gas flow paths 13 are each orthogonal to the secondary coil in a plan view, or each of the plurality of gas flow paths 13 intersects the secondary coil at an angle within the range of 90° ± 45° with respect to the secondary coil in a plan view. As a result, it is possible to suppress abnormal discharge directly below the secondary coil.

[0097] In addition, according to the present embodiment, the plurality of gas flow paths 13 are each formed as a branched flow path structure from one gas supply port 13a to the plurality of gas inlets 13b. As a result, it is possible to uniformly supply the processing gas to the plurality of gas inlets 13b.

[0098] In addition, according to the present embodiment, the gas inlets 13b are provided at positions spaced 5 mm or more from the primary coil and the secondary coil. As a result, it is possible to suppress abnormal discharge.

[0099] In addition, according to the present embodiment, the gas inlets 13b are formed in a spiral shape or a labyrinth structure. As a result, it is possible to suppress abnormal discharge near the gas inlets 13b.

[0100] In addition, according to the present embodiment, the gas flow paths 202 and 203 are arranged at positions where the thickness (thickness 204) of the dielectric window 201 in the longitudinal direction is uniform (uniformly distributed) in the portion (flow paths 202d and 203d) extending in the radial direction. As a result, it is possible to suppress breakage of the dielectric window 201.

[0101] In addition, according to the present embodiment, a gas flow path 15 having a gas supply port 15a and a gas inlet 15b is formed inside the dielectric window 101 at a position longitudinally overlapping with the central region 101a. As a result, it is possible to further control the in-plane uniformity of the processing gas.

[0102] In addition, according to the present embodiment, the antenna assembly is also configured to surround a fourth peripheral region 101e that surrounds the third peripheral region 101d-1. Further, the plurality of gas flow paths 13 each extend in the radial direction of the dielectric window 101-4 to the fourth peripheral region 101e. Further, the gas inlets 13b are each provided at a position longitudinally overlapping with the fourth peripheral region 101e. As a result, the in-plane uniformity of the processing gas can be further improved.

[0103] In addition, according to the present embodiment, the plasma processing apparatus 1 includes a chamber (plasma processing chamber 10), a gas supply unit 20, an antenna assembly (antenna 14), and an RF power supply (first RF generation unit 31a). The chamber is a chamber for accommodating the substrate W, and includes a dielectric window 101 that forms the upper part of the chamber and in which a plurality of gas flow paths 13 are formed inside. The gas supply unit 20 is connected to the plurality of gas flow paths 13 and is configured to be able to supply a processing gas into the chamber. The antenna assembly is disposed above the chamber, and a central region 101a, a first peripheral region 101b that surrounds the central region 101a, and a second peripheral region 101c that surrounds the first peripheral region 101b are defined. The antenna assembly has a coil (inner coil 142) disposed in the first peripheral region 101b. The RF power supply is configured to be able to supply RF electric power to the coil. The plurality of gas flow paths 13 each extend in the radial direction of the dielectric window 101 and are formed such that the distances from the gas supply port 13a connected to the gas supply unit 20 to the gas inlets 13b for introducing the processing gas into the chamber are equal. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0104] In addition, according to the present embodiment, the coil (inner coil 142a) is formed in a substantially circular vortex shape, and the gas inlets 13b are each provided at a position longitudinally overlapping with the first peripheral region 101b-1. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0105] In addition, according to the present embodiment, the coil (inner coil 142b) is formed in a substantially circular vortex shape, and the gas inlets 13b are each provided at a position longitudinally overlapping with at least one of the first peripheral region 101b-2 and the second peripheral region 101c-4. As a result, it is possible to uniformly supply the processing gas while suppressing abnormal discharge.

[0106] The embodiments of the present invention should be considered illustrative in all respects and not restrictive. The above embodiments can also be omitted, replaced, or changed in various ways without departing from the scope of the claims and their gist.

[0107] In addition, the above-described embodiments may be any device that processes a substrate using an ICP-type plasma source. It is not limited to etching and can also be applied to devices that perform film formation, modification, and other processes.

[0108] In addition, the present invention can also adopt the following structure. (1)

[0110] A plasma processing apparatus, comprising:

[0111] A chamber for accommodating a substrate, which includes a dielectric window forming an upper part of the chamber and having a plurality of gas flow paths formed therein;

[0112] A gas supply unit connected to the plurality of gas flow paths and configured to supply a processing gas into the chamber;

[0113] An antenna assembly disposed above the chamber, having a central region, a first peripheral region surrounding the central region, a second peripheral region surrounding the first peripheral region, and a third peripheral region surrounding the second peripheral region, and having a primary coil disposed in the third peripheral region and a secondary coil disposed in the first peripheral region; and

[0114] An RF power supply configured to supply RF (Radio Frequency) electric power to at least one of the primary coil and the secondary coil,

[0115] Each of the plurality of gas flow paths extends in the radial direction of the dielectric window and is formed such that the distance from the gas supply port connected to the gas supply unit to the gas introduction port for introducing the processing gas into the chamber is equal. (2)

[0117] The plasma processing apparatus according to the above (1), wherein each of the gas introduction ports is provided at a position longitudinally overlapping with the second peripheral region. [[ID=3,0]](3)

[0119] The plasma processing apparatus according to the above (1), wherein the primary coil is formed in a substantially circular spiral shape,

[0120] Each of the gas introduction ports is provided at a position longitudinally overlapping with either the second peripheral region or the third peripheral region. (4)

[0122] The plasma processing apparatus according to the above (1), wherein each of the gas supply ports is provided at a position longitudinally overlapping with the central region. (5)

[0124] The plasma processing apparatus according to any one of (1) to (4) above, wherein each of the plurality of gas flow paths is orthogonal to the secondary coil when viewed from above, or crosses the secondary coil when viewed from above at an angle of 90° ± 45° formed by each of the plurality of gas flow paths and the secondary coil when viewed from above. (6)

[0126] The plasma processing apparatus according to any one of (1) to (5) above, wherein each of the plurality of gas flow paths is formed into a branch flow path structure from one gas supply port to a plurality of gas introduction ports. (7)

[0128] The plasma processing apparatus according to any one of (1) to (6) above, wherein the gas supply port and the gas introduction port are provided at positions spaced 5 mm or more from the primary coil and the secondary coil. (8)

[0130] The plasma processing apparatus according to any one of (1) to (7) above, wherein the gas introduction port is formed in a spiral shape or a labyrinth structure. (9)

[0132] The plasma processing apparatus according to any one of (1) to (8) above, wherein the gas flow path is arranged at a position where a portion of the dielectric window extending in the radial direction of the gas flow path has a uniform thickness distribution in the longitudinal direction. (10)

[0134] The plasma processing apparatus according to any one of (1) to (9) above, wherein a gas flow path having the gas supply port and the gas introduction port is formed inside the dielectric window at a position longitudinally overlapping the central region. (11)

[0136] The plasma processing apparatus according to (1) above, wherein

[0137] The antenna assembly is further provided with a fourth peripheral region surrounding the third peripheral region,

[0138] Each of the plurality of gas flow paths extends in the radial direction of the dielectric window to the fourth peripheral region,

[0139] Each of the gas introduction ports is provided at a position longitudinally overlapping the fourth peripheral region. (12)

[0141] A dielectric window forms the upper part of a chamber of a plasma processing apparatus, wherein,

[0142] The dielectric window has a plurality of gas flow paths inside, and the plurality of gas flow paths are arranged to extend in the radial direction of the dielectric window, and are formed such that the distances from a gas supply port connected to a gas supply unit to gas introduction ports for introducing a processing gas into the chamber are equal, wherein the gas supply unit is configured to supply the processing gas into the chamber.

[0143] The gas introduction ports are each provided at a position longitudinally overlapping with a second peripheral region of an antenna assembly, the antenna assembly is disposed above the chamber, a central region, a first peripheral region surrounding the central region, a second peripheral region surrounding the first peripheral region, and a third peripheral region surrounding the second peripheral region are defined, and the antenna assembly has a primary coil disposed in the third peripheral region and a secondary coil disposed in the first peripheral region. (13)

[0145] A plasma processing apparatus includes:

[0146] A chamber for accommodating a substrate, which includes a dielectric window forming the upper part of the chamber and having a plurality of gas flow paths formed inside;

[0147] A gas supply unit connected to the plurality of gas flow paths and configured to be able to supply a processing gas into the chamber;

[0148] An antenna assembly disposed above the chamber, a central region, a first peripheral region surrounding the central region, and a second peripheral region surrounding the first peripheral region are defined, and the antenna assembly has a coil disposed in the first peripheral region; and

[0149] An RF power supply configured to be able to supply RF (radio frequency) electric power to the coil.

[0150] Each of the plurality of gas flow paths of the gas flow paths is arranged to extend in the radial direction of the dielectric window and is formed such that the distances from a gas supply port connected to the gas supply unit to gas introduction ports for introducing the processing gas into the chamber are equal. (14)

[0152] According to the plasma processing apparatus described in (13) above, wherein the gas introduction ports are each provided at a position longitudinally overlapping with the second peripheral region. (15)

[0154] According to the plasma processing apparatus described in (13) above, wherein the coil is formed in a substantially circular vortex shape.

[0155] Each of the gas inlets is provided at a position that overlaps with the first peripheral region in the longitudinal direction. (16)

[0157] The plasma processing apparatus according to (13) above, wherein the coil is formed in a substantially circular vortex shape.

[0158] Each of the gas inlets is provided at a position that overlaps with at least one of the first peripheral region and the second peripheral region in the longitudinal direction. (17)

[0160] The plasma processing apparatus according to (13) above, wherein each of the gas supply ports is provided at a position that overlaps with the central region in the longitudinal direction. (18)

[0162] The plasma processing apparatus according to any one of (13) to (17) above, wherein each of the plurality of gas flow paths is orthogonal to the coil in a plan view, or intersects the coil in a plan view within a range of an angle of 90° ± 45° formed by each of the plurality of gas flow paths and the coil in a plan view. (19)

[0164] The plasma processing apparatus according to any one of (13) to (18) above, wherein each of the plurality of gas flow paths is formed into a branch flow path structure from one of the gas supply ports to a plurality of the gas inlets. (20)

[0166] The plasma processing apparatus according to any one of (13) to (19) above, wherein the gas inlets are provided at positions spaced 5 mm or more from the coil. (21)

[0168] The plasma processing apparatus according to any one of (13) to (20) above, wherein the gas inlets are formed in a spiral shape or a labyrinth structure. (22)

[0170] The plasma processing apparatus according to any one of (13) to (21) above, wherein a plurality of the gas flow paths are arranged in the longitudinal direction of the dielectric window, and the gas flow paths are arranged at positions where the dielectric window in a part where the gas flow paths extend in the radial direction is made uniform in thickness in the longitudinal direction. (23)

[0172] The plasma processing apparatus according to any one of the above (13) to (22), wherein a gas flow path having the gas supply port and the gas introduction port is formed inside the dielectric window at a position longitudinally overlapping with the central region. (24)

[0174] A dielectric window that forms an upper part of a chamber of a plasma processing apparatus, wherein

[0175] the dielectric window has a plurality of gas flow paths inside, the plurality of gas flow paths are radially extended in the dielectric window, and are formed such that distances from a gas supply port connected to a gas supply unit to a gas introduction port for introducing a processing gas into the chamber are equal, wherein the gas supply unit supplies the processing gas into the chamber.

[0176] each of the gas introduction ports is provided at a position longitudinally overlapping with a second peripheral region of an antenna assembly, the antenna assembly is disposed above the chamber, a central region, a first peripheral region surrounding the central region, and a second peripheral region surrounding the first peripheral region are defined, and a coil disposed in the first peripheral region is provided.

[0177] Description of reference numerals

[0178] 1 Plasma processing apparatus

[0179] 10 Plasma processing chamber

[0180] 13, 15, 202, 203, 302, 304, 306 Gas flow path

[0181] 13a, 15a, 202a, 203a Gas supply port

[0182] 13b, 15b, 202b, 203b, 302d, 304c, 306c Gas introduction port 14 Antenna

[0183] 20 Gas supply unit

[0184] 31a First RF generation unit (First RF generation unit)

[0185] 101, 201, 301, 303, 305 Dielectric window

[0186] 101a Central region

[0187] 101b First peripheral region

[0188] 101c Second peripheral region

[0189] 101d Third peripheral region

[0190] 141 Outer coil

[0191] 142 Inner coil

[0192] 202d, 203d flow paths

[0193] 204 Thickness

[0194] W substrate.

Claims

1. A plasma processing apparatus, characterized in that, Comprising: A chamber for accommodating a substrate, which includes a dielectric window forming an upper portion of the chamber and having a plurality of gas flow paths formed therein; A gas supply unit connected to the plurality of gas flow paths and configured to supply a processing gas into the chamber; An antenna assembly disposed above the chamber, having a central region, a first peripheral region surrounding the central region, a second peripheral region surrounding the first peripheral region, and a third peripheral region surrounding the second peripheral region, and having a primary coil disposed in the third peripheral region and a secondary coil disposed in the first peripheral region; And An RF power supply configured to supply RF (radio frequency) electric power to at least one of the primary coil and the secondary coil, Each of the plurality of gas flow paths extends in the radial direction of the dielectric window and is formed such that the distance from a gas supply port connected to the gas supply unit to a gas introduction port for introducing the processing gas into the chamber is equal.

2. The plasma processing apparatus according to claim 1, wherein: Each of the gas introduction ports is provided at a position longitudinally overlapping with the second peripheral region.

3. The plasma processing apparatus according to claim 1, wherein: The primary coil is formed in a substantially circular vortex shape, Each of the gas introduction ports is provided at a position longitudinally overlapping with either the second peripheral region or the third peripheral region.

4. The plasma processing apparatus according to claim 1, wherein: Each of the gas supply ports is provided at a position longitudinally overlapping with the central region.

5. The plasma processing apparatus according to claim 1, wherein: Each of the plurality of gas flow paths is orthogonal to the secondary coil in a top view, or intersects the secondary coil in a top view at an angle within a range of 90° ± 45° formed between each of the plurality of gas flow paths and the secondary coil in a top view.

6. The plasma processing apparatus according to claim 1, wherein: Each of the plurality of gas flow paths is formed as a branched flow path structure from one gas supply port to a plurality of gas introduction ports.

7. The plasma processing apparatus according to claim 1, wherein: The gas introduction ports are provided at positions spaced 5 mm or more from the primary coil and the secondary coil.

8. The plasma processing apparatus according to claim 1, wherein: The gas introduction ports are formed in a spiral shape or a labyrinth structure.

9. The plasma processing apparatus according to claim 1, wherein: The gas flow paths are arranged at positions where the dielectric window portions extending in the radial direction have a uniform thickness distribution in the longitudinal direction.

10. The plasma processing apparatus according to claim 1, wherein: The dielectric window has a gas flow path having the gas supply port and the gas introduction port formed therein at a position longitudinally overlapping with the central region.

11. The plasma processing apparatus according to claim 1, wherein: The antenna assembly is also provided with a fourth peripheral region surrounding the third peripheral region. Each of the plurality of gas flow paths extends in the radial direction of the dielectric window to the fourth peripheral region. Each of the gas inlets is provided at a position longitudinally overlapping with the fourth peripheral region.

12. A dielectric window that forms an upper part of a chamber of a plasma processing apparatus, wherein the dielectric window is characterized in that: The dielectric window has a plurality of gas flow paths inside, and the plurality of gas flow paths extend in the radial direction of the dielectric window and are formed such that the distances from the gas supply port connected to the gas supply unit to the gas introduction port for introducing the processing gas into the chamber are equal. Among them, The gas supply unit is configured to supply the processing gas into the chamber. Each of the gas inlets is provided at a position longitudinally overlapping with a second peripheral region of an antenna assembly, wherein the antenna assembly is disposed above the chamber, has a central region, a first peripheral region surrounding the central region, a second peripheral region surrounding the first peripheral region, and a third peripheral region surrounding the second peripheral region, and includes a primary coil disposed in the third peripheral region and a secondary coil disposed in the first peripheral region.

13. A plasma processing apparatus, characterized in that, Comprising: A chamber for accommodating a substrate, including a dielectric window that forms an upper part of the chamber and has a plurality of gas flow paths formed therein; A gas supply unit connected to the plurality of gas flow paths and configured to be able to supply a processing gas into the chamber; An antenna assembly disposed above the chamber, having a central region, a first peripheral region surrounding the central region, and a second peripheral region surrounding the first peripheral region, and including a coil disposed in the first peripheral region; And An RF power supply configured to be able to supply RF (radio frequency) electric power to the coil. Each of the plurality of gas flow paths extends in the radial direction of the dielectric window, and is formed such that the distances from a gas supply port connected to the gas supply unit to a gas inlet for introducing the processing gas into the chamber are equal.

14. The plasma processing apparatus according to claim 13, wherein: Each of the gas inlets is provided at a position longitudinally overlapping with the second peripheral region.

15. The plasma processing apparatus according to claim 13, wherein: The coil is formed in a substantially circular spiral shape. Each of the gas inlets is provided at a position longitudinally overlapping with the first peripheral region.

16. The plasma processing apparatus according to claim 13, wherein: The coil is formed in a substantially circular spiral shape. Each of the gas inlets is provided at a position longitudinally overlapping with at least one of the first peripheral region and the second peripheral region.

17. The plasma processing apparatus according to claim 13, wherein: Each of the gas supply ports is provided at a position longitudinally overlapping with the central region.

18. The plasma processing apparatus according to claim 13, wherein: Each of the plurality of gas flow paths is orthogonal to the coil in a top view, or intersects the coil in a top view within a range where the angle formed by each of the plurality of gas flow paths and the coil in a top view is 90° ± 45°.

19. The plasma processing apparatus according to claim 13, wherein: Each of the plurality of gas flow paths is formed into a branched flow path structure from one of the gas supply ports to the plurality of gas introduction ports.

20. The plasma processing apparatus according to claim 13, wherein: The gas introduction port is provided at a position spaced 5 mm or more from the coil.

21. The plasma processing apparatus according to claim 13, wherein: The gas introduction port is formed in a spiral shape or a labyrinth structure.

22. The plasma processing apparatus according to claim 13, wherein: A plurality of the gas flow paths are arranged longitudinally in the dielectric window, and the gas flow paths are arranged at positions where the dielectric window in a part where the gas flow path extends in the radial direction makes the thickness in the longitudinal direction uniformly distributed.

23. The plasma processing apparatus according to claim 13, wherein: The dielectric window has a gas flow path having the gas supply port and the gas introduction port formed therein at a position longitudinally overlapping with the central region.

24. A dielectric window that constitutes an upper part of a chamber of a plasma processing apparatus, the dielectric window being characterized in that: The dielectric window has a plurality of gas flow paths inside, the plurality of gas flow paths extending in the radial direction of the dielectric window and formed such that the distances from the gas supply port connected to the gas supply section to the gas introduction port for introducing the processing gas into the chamber are equal, wherein, The gas supply unit is configured to supply the processing gas into the chamber, The gas introduction ports are each provided at a position longitudinally overlapping with a second peripheral region of the antenna assembly, the antenna assembly being arranged above the chamber, having a central region, a first peripheral region surrounding the central region, and the second peripheral region surrounding the first peripheral region, and having a coil arranged in the first peripheral region.

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