Plasma processing device

Abstract

The present invention provides a plasma processing device for stably igniting and maintaining plasma.　This plasma processing device includes: a plasma processing chamber that forms a plasma processing space; a substrate support part that is provided in the plasma processing chamber; a gas introduction part that introduces gas into the plasma processing space; an antenna that is provided above the plasma processing chamber and to which a source RF signal for plasma generation is supplied; an AC power supply that supplies the source RF signal to the antenna; an electromagnet that is provided radially outward of the antenna and has an annular coil arranged concentrically with a center axis of the substrate support part; a DC power supply that supplies power to the coil of the electromagnet; and a control unit. The control unit controls the DC power supply within an ampere turns range of 356-600, which is a product of the number of turns of the coil of the electromagnet and the current flowing in the coil of the electromagnet.

Description

Plasma processing equipment

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

[0002] Patent Document 1 discloses a plasma processing apparatus comprising a processing vessel, a mounting table provided within the processing vessel on which an object to be processed is placed, a dielectric having a facing surface facing the mounting table, a planar antenna provided on the surface of the dielectric opposite the facing surface and introducing an induction electric field for plasma excitation into the processing vessel via the dielectric, and a group of electromagnets arranged along the outer periphery of the processing vessel and forming a magnetic field within the processing vessel that moves ions in the plasma based on the induction electric field along the facing surface of the dielectric.

[0003] JP 2018-98094 A

[0004] In one aspect, the present disclosure provides a plasma processing apparatus that stably ignites and maintains a plasma.

[0005] In order to solve the above problem, according to one aspect, a plasma processing apparatus can be provided, comprising: a plasma processing chamber forming a plasma processing space; a substrate support provided within the plasma processing chamber; a gas inlet for introducing gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply for supplying the source RF signal to the antenna; an electromagnet provided radially outward of the antenna and having an annular coil arranged concentrically with a central axis of the substrate support; a DC power supply for supplying power to the coil of the electromagnet; and a controller, wherein the controller controls the DC power supply so that the number of ampere-turns, which is the product of the number of turns in the coil of the electromagnet and the current flowing through the coil of the electromagnet, is within a range of 356 to 600.

[0006] According to one aspect, it is possible to provide a plasma processing apparatus that stably ignites and maintains plasma.

[0007] An example of a diagram for explaining an example of the configuration of an inductively coupled plasma processing apparatus. An example of a partially enlarged view of a plasma processing apparatus. A graph showing an example of the number of combinations of the frequency of a source RF signal that allows easy ignition and maintenance and the adjustment range of a matching box. A graph showing an example of the number of combinations of the frequency of a source RF signal that allows easy ignition and the adjustment range of a matching box. An example of a graph showing the relationship between the number of ampere turns and magnetic flux density of an electromagnet coil. An example of a graph showing the relationship between the wire diameter of a coil and electrical characteristics. An example of a prototype electromagnet coil. An example of a diagram showing the relationship between magnetic field strength and current value in each coil.

[0008] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0009] [Plasma Processing System] An example of the configuration of a plasma processing system will be described below with reference to Figures 1 and 2. Figure 1 is an example of a diagram for explaining an example of the configuration of an inductively coupled plasma processing apparatus 1. Figure 2 is an example of a partially enlarged view of the plasma processing apparatus 1. Note that Figure 2 shows the structure of the upper part of a plasma processing chamber 10, with the central gas injection unit 13 omitted.

[0010] 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. The plasma processing apparatus 1 also includes a substrate support 11, a gas inlet, and an antenna 14. The substrate support 11 is disposed within 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, a sidewall 102 of the plasma processing chamber 10, and the substrate support 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 exhaust port for exhausting gas from the plasma processing space 10s. The plasma processing chamber 10 is grounded.

[0011] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region 111a for supporting a substrate W and an annular region 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. Therefore, the central region 111a is also called a substrate support surface for supporting the substrate W, and the annular region 111b is also called a ring support surface for supporting the ring assembly 112.

[0012] In one embodiment, the main body 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 also has an annular region 111b. Note that the annular region 111b may also be provided by another member surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member. In this case, the ring assembly 112 may be disposed on the annular electrostatic chuck or the annular insulating member, or may be disposed on both the electrostatic chuck 1111 and the annular insulating member. Furthermore, 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) may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple bias electrodes. Alternatively, the electrostatic electrode 1111b may function as a bias electrode. Therefore, the substrate support 11 includes at least one bias electrode.

[0013] 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 rings are formed of a conductive or insulating material, and the cover rings are formed of an insulating material.

[0014] The substrate support 11 may also include a temperature adjustment module configured 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 passage 1110a, or a combination thereof. A heat transfer fluid such as brine or a gas flows through the flow passage 1110a. In one embodiment, the flow passage 1110a is formed in the base 1110, and one or more heaters are disposed in the ceramic member 1111a of the electrostatic chuck 1111. The substrate support 11 may also include a heat transfer gas supply configured to supply a heat transfer gas to a gap between the backside of the substrate W and the central region 111a.

[0015] The gas inlet is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. In one embodiment, the gas inlet includes a center gas injector (CGI) 13. The center gas injector 13 is disposed above the substrate support 11 and attached to a central opening formed in the dielectric window 101. The center gas injector 13 has at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas inlet port 13c. The process gas supplied to the gas supply port 13a passes through the gas flow path 13b and is introduced into the plasma processing space 10s from the gas inlet port 13c. Note that the gas inlet may include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 102 in addition to or instead of the center gas injector 13.

[0016] The gas supply unit 20 may include at least one gas source 21 and at least one flow controller 22. In one embodiment, the gas supply unit 20 is configured to supply at least one process gas from a corresponding gas source 21 to the gas inlet through a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0017] 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 supply at least one RF signal (RF power) to at least one bias electrode and the antenna 14. This causes a plasma to be formed from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate a plasma from one or more process gases in the plasma processing chamber 10. Furthermore, by supplying a bias RF signal to the at least one bias electrode, a bias potential is generated on the substrate W, thereby attracting ions in the formed plasma to the substrate W.

[0018] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to the antenna 14 and configured to generate a source RF signal (source RF 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 generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to the antenna 14.

[0019] The second RF generator 31b is coupled to at least one bias electrode via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF 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 generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one bias electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0020] 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 generator 32a. In one embodiment, the bias DC generator 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 the at least one bias electrode.

[0021] In various embodiments, the bias DC signal may be pulsed. In this case, a sequence of voltage pulses is applied to at least one bias electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the bias DC generator 32a and at least one bias electrode. Thus, the bias DC generator 32a and the waveform generator constitute a voltage pulse generator. The voltage pulses may have positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one cycle. Note that the bias DC generator 32a may be provided in addition to the RF power supply 31 or may be provided instead of the second RF generator 31b.

[0022] The antenna 14 includes one or more coils. In one embodiment, the antenna 14 may include an outer coil and an inner coil arranged coaxially. In this case, the RF power supply 31 may be connected to both the outer coil and the inner coil, or to either the outer coil or the inner coil. In the former case, the same RF generator may be connected to both the outer coil and the inner coil, or separate RF generators may be connected to the outer coil and the inner coil separately.

[0023] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s is regulated by the pressure regulating valve. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0024] The plasma processing apparatus 1 also includes a magnetic field generating unit 50 that generates a magnetic field in the plasma processing space 10s. The magnetic field generating unit 50 includes an electromagnet 51 and a power supply 52.

[0025] The electromagnet 51 has an annular coil that is arranged concentrically with the central axis of the substrate support 11 (an axis that passes through the center of the substrate support surface and is perpendicular to the substrate support surface). As shown in Fig. 2, the electromagnet 51 is arranged above the plasma processing chamber 10 (dielectric window 101). The electromagnet 51 is also arranged radially outward of the diameter D14 of the antenna 14.

[0026] Furthermore, electromagnet 51 is disposed radially inward of diameter D10 of the inner wall of plasma processing chamber 10. Note that electromagnet 51 may also be configured to be disposed radially outward of diameter D10 of the inner wall of plasma processing chamber 10.

[0027] Specifically, if the diameter D14 of the antenna 14 is in the range of 300 mm to 500 mm and the diameter D10 of the inner wall of the plasma processing chamber 10 is in the range of 540 mm to 580 mm, the inner diameter of the coil of the electromagnet 51 is preferably in the range of 540 mm to 640 mm.

[0028] A power supply (DC power supply) 52 supplies power to the coil of the electromagnet 51. This causes the electromagnet 51 to generate a magnetic field within the plasma processing space 10s. The power supply 52 supplies continuous wave or pulsed power to the coil of the electromagnet 51, thereby generating a continuous wave or pulsed magnetic field within the plasma processing space 10s.

[0029] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The control unit 2 may be configured to control each element of the plasma processing apparatus 1 to perform 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 may be implemented by, for example, a computer 2a. The processing unit 2a1 may be configured to read a program from the storage unit 2a2 and execute the read program to perform various control operations. This program may be stored in the storage unit 2a2 in advance or may be acquired via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 by the processing unit 2a1 for execution. The medium may be various storage media readable by the computer 2a or a communication line connected to the communication interface 2a3. The processing unit 2a1 may be a CPU (Central Processing Unit). 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 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0030] Next, a method for generating plasma in the plasma processing space 10s using the plasma processing apparatus 1 will be described.

[0031] Improved plasma uniformity is required as semiconductor devices formed on substrates W become smaller. In addition, in plasma etching processes, the plasma generated in plasma processing chamber 10 controlled at a low pressure (1 mTorr to 20 mTorr) becomes more uniform, resulting in improved uniformity of the etching rate.

[0032] On the other hand, under low pressure, the density of gas molecules is low and collisions between gas molecules are reduced, making it difficult to ignite and maintain plasma. Furthermore, with the miniaturization of semiconductor devices formed on the substrate W, there is a limit to how much the strength of the source RF signal (source RF power) that generates plasma can be increased.

[0033] By applying a magnetic field from the magnetic field generating unit 50, the charged particles of the plasma move along the magnetic field lines. This increases the distance the charged particles travel before reaching the sheath. In other words, the probability that the charged particles will collide with other gas molecules before reaching the sheath increases, increasing the density of the plasma. This makes it possible to suppress deactivation of the plasma even under low pressure.

[0034] Furthermore, when generating plasma, it is preferable that the control unit 2 first controls the power supply 52 to supply power to the coil of the electromagnet 51, and then controls the first RF generating unit 31a to supply a source RF signal to the antenna 14. This makes it easier to ignite plasma.

[0035] In the plasma processing space 10s, a dynamic magnetic flux is generated by supplying a source RF signal to the antenna 14, and a static magnetic flux is generated by the magnetic field generation unit 50. If the strength of the static magnetic field generated by the magnetic field generation unit 50 is made too strong, it may hinder the generation of inductively coupled plasma (ICP) generated by supplying a source RF signal to the antenna 14. For this reason, the magnetic field generation unit 50 is required to have an appropriate static magnetic field strength and static magnetic field distribution that do not deteriorate the efficiency of generating inductively coupled plasma.

[0036] Here, the static magnetic field strength in the vicinity of the antenna 14 that forms a dynamic magnetic flux and directly below the dielectric window (top panel) 101 will be described.

[0037] FIG. 3 is a graph showing an example of the number of combinations of the frequency of the source RF signal and the adjustment range of the matching box that are easy to ignite and maintain.

[0038] Here, the reflectivity was measured for each combination (data point) of the frequency of the source RF signal applied to the antenna 14 at the time of plasma ignition and the adjustment range (variable capacitance) of the matching box provided in the power supply, with the pressure in the plasma processing chamber 10 set to 3 mTorr and each static magnetic field strength (0 G to 30.6 G). Data points with a reflectivity of 50% or less were then counted.

[0039] Similarly, for each static magnetic field strength (0 G to 30.6 G), the reflectivity was measured for each combination (data point) of the frequency of the source RF signal applied to the antenna 14 during plasma maintenance and the adjustment range (variable capacitance) of the matching box provided in the power supply. Data points with a reflectivity of 50% or less were counted.

[0040] As shown in Figure 3, when the static magnetic field strength is in the range of 13 G to 22 G (in the example of Figure 3, the range of 12.9 G to 20.5 G indicated by the dashed line), the number of data points where the reflectivity is 50% or less at the time of ignition and during maintenance increases. This indicates that there is a wide range of combinations of the frequency of the source RF signal applied to the antenna 14 and the adjustment range (variable capacitance) of the matching box that improves both the ability to ignite the plasma and the ability to maintain the plasma.

[0041] In other words, by setting the static magnetic field strength generated by the magnetic field generating unit 50 to within the range of 13 G to 22 G, the range of selectable combinations of the frequency of the source RF signal applied to the antenna 14 and the adjustment range (variable capacitance) of the matching box, which can ignite and maintain inductively coupled plasma, is expanded, thereby making it possible to stably ignite and maintain plasma under low pressure.

[0042] FIG. 4 is a graph showing an example of the number of combinations of the frequency of the source RF signal that allows easy ignition and the adjustment range of the matching box.

[0043] Here, for each combination of pressure (3 mTorr, 10 mTorr) and static magnetic field strength (0 G to 22.8 G) in the plasma processing chamber 10, the reflectance was measured for each combination (data point) of the frequency of the source RF signal applied to the antenna 14 at the time of plasma ignition and the adjustment range (variable capacitance) of the matching box provided in the power supply, when the source RF signal supplied to the antenna 14 was a continuous wave (CW) or pulsed. Data points with a reflectance of 50% or less were then counted.

[0044] As shown in Figure 4, by setting the static magnetic field strength generated by the magnetic field generator 50 to a range of 13 G to 22 G (18.0 G in the example of Figure 4), the range of selectable combinations of the frequency of the source RF signal applied to the antenna 14 and the adjustment range (variable capacitance) of the matching box, which can ignite and maintain inductively coupled plasma, is expanded within a pressure range of 3 mTorr to 10 mTorr within the plasma processing chamber 10. Furthermore, whether the source RF signal supplied to the antenna 14 is continuous wave (CW) or pulsed (Pulse), the range of selectable combinations of the frequency of the source RF signal applied to the antenna 14 and the adjustment range (variable capacitance) of the matching box, which can ignite inductively coupled plasma, is expanded. This allows stable ignition and maintenance of plasma under low pressure.

[0045] 5 is an example of a graph showing the relationship between the number of ampere turns and magnetic flux density of the coil of the electromagnet 51. The number of ampere turns (AT) on the horizontal axis is the product of the number of turns (windings) of the coil and the current (amperes) flowing through the coil. The vertical axis is the magnetic flux density (G).

[0046] As shown in FIG. 5, once the required magnetic flux density (20 G in the example of FIG. 5) is determined, the required number of ampere turns can be determined from the graph shown in FIG.

[0047] As a result, when the static magnetic field strength generated by electromagnet 51 is in the range of 13 G to 22 G, the number of ampere turns of the coil of electromagnet 51 is in the range of 356 AT to 600 AT. In other words, by setting the number of ampere turns of the coil of electromagnet 51 in the range of 356 AT to 600 AT, the range of selectable combinations of the frequency of the source RF signal applied to antenna 14 and the adjustment range (variable capacitance) of the matching box, which can ignite and maintain inductively coupled plasma, is expanded. This makes it possible to stably ignite and maintain plasma under low pressure.

[0048] 6 is an example of a graph showing the relationship between coil wire diameter and electrical characteristics. Here, the relationship between coil wire diameter and electrical characteristics is shown as an example for 600 AT, which is the upper limit of the ampere-turn range. The horizontal axis is the wire diameter (diameter) of the coil of the electromagnet 51. The graph indicated by black circles is the voltage (required voltage) applied to the coil when the ampere-turn number is 600 AT. The graph indicated by white circles is the current (required current) flowing through the coil when the ampere-turn number is 600 AT.

[0049] In the region S2 where the wire diameter of the coil of the electromagnet 51 is less than 0.5 mm, the voltage applied to the coil increases. On the other hand, in the region S3 where the wire diameter of the coil is greater than 2.1 mm, the current flowing through the coil increases. This requires a power supply 52 with a higher output, which may increase costs.

[0050] For this reason, the wire diameter of the coil of electromagnet 51 is preferably within a range of 0.5 mm to 2.1 mm (region S1). Note that, as shown in Fig. 6, the required current when the wire diameter of the coil of electromagnet 51 is 0.5 mm is 1.3 A, and the required current when the wire diameter of the coil of electromagnet 51 is 2.1 mm is 20 A. For this reason, the current flowing through the coil is preferably within a range of 1.3 A to 20 A.

[0051] Furthermore, if the wire diameter of the coil of electromagnet 51 is 2.1 mm and the static magnetic field strength is 13 G (ampere turns 356 AT), and the number of coil turns is 30, the current will be 11.8 A. Furthermore, if the wire diameter of the coil of electromagnet 51 is 0.5 mm and the static magnetic field strength is 22 G (ampere turns 600 AT), and the number of coil turns is 455, the current will be 1.32 A. Therefore, it is preferable that the number of coil turns of electromagnet 51 be within the range of 30 to 455.

[0052] 7 is a diagram showing an example of the coils of the prototype electromagnet 51. Here, a first coil (E-mag A), a second coil (E-mag B), and a third coil (E-mag C) were prototyped.

[0053] The first coil (E-magA) has a wire diameter of 0.7 mm. In this case, when the number of ampere turns is set to the maximum (600 AT), the maximum value of the current flowing through the coil is 2.0 A, as shown in Figure 6. In the first coil (E-magA), by setting the number of turns to 293 and passing the desired current through the coil, the number of ampere turns was able to be set to 585 (equivalent to a magnetic field strength of 21.9 G).

[0054] The second coil (E-magB) has a wire diameter of 0.95 mm. In this case, the maximum current flowing through the coil when the number of ampere turns is set to the maximum (600 AT) is 3.9 A, as shown in Figure 6. In the second coil (E-magB), by setting the number of turns to 150 and passing the desired current through the coil, the number of ampere turns was able to be set to 585 (equivalent to a magnetic field strength of 21.9 G).

[0055] The third coil (E-magC) has a wire diameter of 1.4 mm. In this case, the maximum value of the current flowing through the coil when the number of ampere turns is set to the maximum (600 AT) is 7.5 A, as shown in Figure 6. In the third coil (E-magC), by setting the number of turns to 78 and passing the desired current through the coil, the number of ampere turns was able to be set to 585 (equivalent to a magnetic field strength of 21.9 G).

[0056] Figure 8 shows an example of the relationship between the magnetic field strength and the current value in each coil. Here, the current flowing through the first coil (E-mag A), second coil (E-mag B), and third coil (E-mag C) was controlled to achieve the desired magnetic field strength.

[0057] As shown in Figure 8, the desired magnetic field strength can be generated by controlling the current in any of the first coil (E-mag A), second coil (E-mag B), and third coil (E-mag C).

[0058] The embodiments disclosed above include, for example, the following: (Supplementary Note 1) A plasma processing apparatus comprising: a plasma processing chamber forming a plasma processing space; a substrate support provided within the plasma processing chamber; a gas inlet for introducing gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply for supplying the source RF signal to the antenna; an electromagnet provided radially outward of the antenna and having an annular coil arranged concentrically with the central axis of the substrate support; a DC power supply for supplying power to the coil of the electromagnet; and a controller, wherein the controller controls the DC power supply so that the number of ampere-turns, which is the product of the number of turns in the coil of the electromagnet and the current flowing through the coil of the electromagnet, is within a range of 356 to 600. (Supplementary Note 2) The plasma processing apparatus according to Supplementary Note 1, wherein the wire diameter of the coil of the electromagnet is within a range of 0.5 mm to 2.1 mm. (Supplementary Note 3) The plasma processing apparatus according to Supplementary Note 1 or 2, wherein the number of turns in the coil of the electromagnet is within a range of 30 to 455. (Supplementary Note 4) The plasma processing apparatus according to any of Supplementary Notes 1 to 3, wherein a current flowing through the coil of the electromagnet is within a range of 1.3 A to 20 A. (Supplementary Note 5) A plasma processing apparatus comprising: a plasma processing chamber forming a plasma processing space; a substrate support provided in the plasma processing chamber; a gas inlet configured to introduce a gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply that supplies the source RF signal to the antenna; an electromagnet provided radially outward of the antenna and having an annular coil arranged concentrically with a central axis of the substrate support; a DC power supply that supplies power to the coil of the electromagnet; and a controller, wherein the number of turns in the coil of the electromagnet is within a range of 30 to 455. (Supplementary Note 6) The plasma processing apparatus according to Supplementary Note 5, wherein a wire diameter of the coil of the electromagnet is in the range of 0.5 mm to 2.1 mm. (Supplementary Note 7) The plasma processing apparatus according to Supplementary Note 5 or 6, wherein a current flowing through the coil of the electromagnet is in the range of 1.3 A to 20 A.(Supplementary Note 8) A plasma processing apparatus comprising: a plasma processing chamber forming a plasma processing space; a substrate support provided within the plasma processing chamber; a gas inlet for introducing gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply for supplying the source RF signal to the antenna; an electromagnet provided radially outward of the antenna and having an annular coil arranged concentrically with a central axis of the substrate support; a DC power supply for supplying power to the coil of the electromagnet; and a controller, wherein the controller controls the DC power supply so that a static magnetic field strength directly below a top plate of the plasma processing chamber is in a range of 13 G to 22 G. (Supplementary Note 9) The plasma processing apparatus according to any one of Supplementary Notes 1 to 8, wherein an inner diameter of the coil of the electromagnet is 540 mm or more and 640 mm or less. (Supplementary Note 10) The plasma processing apparatus according to any one of Supplementary Notes 1 to 9, wherein a pressure inside the plasma processing chamber is 3 mTorr or more and 10 mTorr or less. (Supplementary Note 11) The plasma processing apparatus according to any one of Supplementary Note 1 to Supplementary Note 10, wherein the control unit executes the steps of: controlling the DC power supply to supply power to the coil of the electromagnet; and, after supplying power to the coil of the electromagnet, controlling the AC power supply to supply the source RF signal to the antenna.

[0059] The present invention is not limited to the configurations described in the above embodiments, but may be combined with other elements, etc. These aspects can be changed without departing from the spirit of the present invention, and can be appropriately determined depending on the application form.

[0060] This application claims priority based on Japanese Patent Application No. 2023-213217, filed on December 18, 2023, the entire contents of which are incorporated herein by reference.

[0061] REFERENCE SIGNS LIST 1 Plasma processing apparatus 2 Control unit 10 Plasma processing chamber 10s Plasma processing space 101 Dielectric window 102 Side wall 11 Substrate support unit 13 Central gas injection unit 14 Antenna 20 Gas supply unit 30 Power supply 31 RF power supply 31a First RF generation unit 31b Second RF generation unit 32 DC power supply 32a Bias DC generation unit 40 Exhaust system 50 Magnetic field generation unit 51 Electromagnet 52 Power supply (DC power supply) W Substrate

Claims

1. A plasma processing apparatus comprising: a plasma processing chamber which forms a plasma processing space; a substrate support part provided within the plasma processing chamber; a gas inlet part which introduces gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply which supplies the source RF signal to the antenna; an electromagnet which is provided radially outward of the antenna and has a ring-shaped coil arranged concentrically with a central axis of the substrate support part; a DC power supply which supplies power to the coil of the electromagnet; and a control part, wherein the control part controls the DC power supply so that the number of ampere turns, which is the product of the number of turns of the coil of the electromagnet and the current flowing through the coil of the electromagnet, is within a range of 356 to 600.

2. The plasma processing apparatus according to claim 1, wherein the wire diameter of the coil of the electromagnet is within a range of 0.5 mm to 2.1 mm.

3. The plasma processing apparatus according to claim 1, wherein the number of turns of the coil of the electromagnet is within a range of 30 to 455.

4. The plasma processing apparatus according to claim 1, wherein the current flowing through the coil of the electromagnet is within the range of 1.3 A to 20 A.

5. A plasma processing apparatus comprising: a plasma processing chamber forming a plasma processing space; a substrate support provided within the plasma processing chamber; a gas inlet for introducing gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply for supplying the source RF signal to the antenna; an electromagnet having an annular coil disposed concentrically with a central axis of the substrate support provided radially outward of the antenna; a DC power supply for supplying power to the coil of the electromagnet; and a control unit, wherein the number of turns of the coil of the electromagnet is within the range of 30 to 455.

6. The plasma processing apparatus according to claim 5, wherein the wire diameter of the coil of the electromagnet is within a range of 0.5 mm to 2.1 mm.

7. The plasma processing apparatus according to claim 5, wherein the current flowing through the coil of the electromagnet is within the range of 1.3 A to 20 A.

8. A plasma processing apparatus comprising: a plasma processing chamber which forms a plasma processing space; a substrate support part provided within the plasma processing chamber; a gas inlet part which introduces gas into the plasma processing space; an antenna provided above the plasma processing chamber and supplied with a source RF signal for plasma generation; an AC power supply which supplies the source RF signal to the antenna; an electromagnet which is provided radially outward of the antenna and has a ring-shaped coil arranged concentrically with a central axis of the substrate support part; a DC power supply which supplies power to the coil of the electromagnet; and a control part, wherein the control part controls the DC power supply so that a static magnetic field strength directly below a top plate of the plasma processing chamber is within a range of 13 G to 22 G.

9. The plasma processing apparatus according to claim 1, wherein the inner diameter of the coil of the electromagnet is not less than 540 mm and not more than 640 mm.

10. The plasma processing apparatus according to claim 1, wherein the pressure in the plasma processing chamber is equal to or higher than 3 mTorr and equal to or lower than 10 mTorr.

11. A plasma processing apparatus as described in any one of claims 1 to 8, wherein the control unit executes the steps of: controlling the DC power supply to supply power to the coil of the electromagnet; and, after supplying power to the coil of the electromagnet, controlling the AC power supply to supply the source RF signal to the antenna.

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