Plasma processing device, and plasma processing method

Abstract

The disclosed plasma processing device includes a chamber, a substrate supporting portion, and at least one power source. The substrate supporting portion includes an electrostatic chuck, a gas hole, and an insulating member. The gas hole opens in the upper surface of the electrostatic chuck in order to supply a heat transfer gas to a gap between the electrostatic chuck and the rear surface of a substrate. The insulating member is disposed in the gas hole. The electrostatic chuck includes a dielectric portion, a first electrode, and a second electrode. The first electrode is disposed in the dielectric portion to generate an electrostatic attractive force by means of the electrostatic chuck. The second electrode extends so as to surround the insulating member in the dielectric portion between the first electrode and the insulating member. The at least one power source is configured to apply independent voltages to each of the first electrode and the second electrode.

Description

Plasma processing apparatus and plasma processing method

[0001] SUMMARY OF THE INVENTION Exemplary embodiments of the present disclosure relate to a plasma processing apparatus and a plasma processing method.

[0002] A plasma processing apparatus is used in plasma processing of a substrate. The plasma processing apparatus includes a chamber and an electrostatic chuck. The electrostatic chuck is disposed in the chamber. The electrostatic chuck includes a gas hole for supplying a heat transfer gas between the substrate and the electrostatic chuck. Patent Document 1 listed below discloses an electrostatic chuck in which a porous plug is disposed in the gas hole.

[0003] JP 2023-92822 A

[0004] The present disclosure provides a gas hole for supplying a heat transfer gas to a gap between an electrostatic chuck and a substrate, and a technique for suppressing discharge in the gap.

[0005] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus includes a chamber, a substrate support, a plasma generating unit, and at least one power supply. The substrate support has an electrostatic chuck and is disposed within the chamber. The plasma generating unit is configured to generate plasma from a gas within the chamber. The at least one power supply is connected to the substrate support. The substrate support includes a gas hole and an insulating member. The gas hole is open in the top surface of the electrostatic chuck for supplying a heat transfer gas to a gap between the electrostatic chuck and the backside of the substrate. The insulating member is disposed within the gas hole. The electrostatic chuck includes a dielectric portion, a first electrode, and a second electrode. The first electrode is disposed within the dielectric portion for attracting the substrate to the electrostatic chuck by electrostatic attraction. The second electrode extends within the dielectric portion and between the first electrode and the insulating member to surround the insulating member. The at least one power supply is electrically connected to the first electrode and the second electrode to apply independent voltages to the first electrode and the second electrode, respectively.

[0006] According to one exemplary embodiment, it is possible to provide a gas hole for supplying a heat transfer gas to a gap between an electrostatic chuck and a substrate, and to suppress discharge in the gap.

[0007] FIG. 4 is a diagram for explaining an example of the configuration of a plasma processing system. FIG. 4 is a diagram for explaining an example of the configuration of a capacitively coupled plasma processing apparatus. FIG. 4 is a diagram showing a substrate support and a power supply that can be employed in a plasma processing apparatus according to an exemplary embodiment. FIG. 4( a) is a plan view showing an electrostatic chuck of a substrate support according to an exemplary embodiment, and FIG. 4( b) is a plan view showing gas holes, an insulating member, and a second electrode in the substrate support according to an exemplary embodiment. FIG. 4 is a diagram showing an example of a substrate support and a power supply employed in a plasma processing apparatus according to an exemplary embodiment. FIG. 4 is a diagram showing an example of a substrate support and a power supply employed in a plasma processing apparatus according to an exemplary embodiment. FIG. 4 is a diagram showing an example of a substrate support and a power supply employed in a plasma processing apparatus according to an exemplary embodiment. FIG. 4 is a flow chart showing a plasma processing method according to an exemplary embodiment. FIG. 4 is a block diagram of a processing circuit for performing the operations described herein on a computer.

[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] FIG. 1 is a diagram illustrating an exemplary configuration of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing apparatus 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing apparatus 1 is an example of a substrate processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0010] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Various types of plasma generators may be used, including alternating current (AC) plasma generators and direct current (DC) plasma generators. In one embodiment, the AC signal (AC power) used in the AC plasma generator has a frequency in the range of 100 kHz to 10 GHz. Thus, AC signals include radio frequency (RF) signals and microwave signals. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0011] 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).

[0012] The following describes a configuration example of a capacitively coupled plasma processing apparatus as an example of the plasma processing apparatus 1. Fig. 2 is a diagram for explaining a configuration example of a capacitively coupled plasma processing apparatus.

[0013] The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 is grounded. The showerhead 13 and the substrate support 11 are electrically insulated from the housing of the plasma processing chamber 10.

[0014] 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.

[0015] 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 lower 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 power supply 31 and / or a DC power supply 32, which will be described later, may be disposed within the ceramic member 1111a. In this case, the at least one RF / DC electrode functions as a lower electrode. When a bias RF signal and / or a DC signal, which will be described later, is supplied to the at least one RF / DC electrode, the RF / DC electrode is also called a bias electrode. Note that the conductive member of the base 1110 and the at least one RF / DC electrode may function as multiple lower electrodes. Furthermore, the electrostatic electrode 1111b may function as a lower electrode. Therefore, the substrate support 11 includes at least one lower electrode.

[0016] 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.

[0017] 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 unit configured to supply a heat transfer gas to a gap between the back surface Wb of the substrate W and the central region 111a.

[0018] The showerhead 13 is configured to introduce at least one process gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The process gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes at least one upper electrode. In addition to the showerhead 13, the gas inlet may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[0019] 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 showerhead 13 via 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 at least one flow modulation device that modulates or pulses the flow rate of the at least one process gas.

[0020] 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 lower electrode and / or at least one upper electrode. This generates a plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the at least one lower electrode, a bias potential is generated on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0021] 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 at least one lower electrode and / or at least one upper electrode via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. 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 at least one lower electrode and / or at least one upper electrode.

[0022] The second RF generator 31b is coupled to at least one lower 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 lower electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0023] 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 first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to the at least one lower electrode and configured to generate a first DC signal. The generated first DC signal is applied to the at least one lower electrode. In one embodiment, the second DC generator 32b is connected to the at least one upper electrode and configured to generate a second DC signal. The generated second DC signal is applied to the at least one upper electrode.

[0024] In various embodiments, the first and second DC signals may be pulsed. In this case, a sequence of voltage pulses is applied to at least one lower electrode and / or at least one upper electrode. The voltage pulses may have a rectangular, trapezoidal, triangular, or combination thereof pulse waveform. In one embodiment, a waveform generator for generating the sequence of voltage pulses from the DC signal is connected between the first DC generator 32a and at least one lower electrode. Thus, the first DC generator 32a and the waveform generator constitute a voltage pulse generator. When the second DC generator 32b and the waveform generator constitute a voltage pulse generator, the voltage pulse generator is connected to at least one upper electrode. The voltage pulses may have either 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 period. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0025] 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.

[0026] An example of a substrate support that can be employed in a plasma processing apparatus according to an exemplary embodiment will be described below with reference to Figures 3, 4(a), and 4(b). Figure 3 is a diagram showing a substrate support and a power supply that can be employed in a plasma processing apparatus according to an exemplary embodiment. Figure 4(a) is a plan view showing an electrostatic chuck of the substrate support according to an exemplary embodiment, and Figure 4(b) is a plan view showing gas holes, an insulating member, and a second electrode in the substrate support according to an exemplary embodiment.

[0027] 3 can be used as a substrate support of the plasma processing apparatus 1. As described above, the substrate support 11 includes the base 1110 and the electrostatic chuck 1111. The electrostatic chuck 1111 is provided on the base 1110.

[0028] The electrostatic chuck 1111 has a plurality of protrusions 1111 p. The substrate W is placed on the top surface of each of the plurality of protrusions 1111 p. When the substrate W is placed on the electrostatic chuck 1111, a gap G is formed between the electrostatic chuck 1111 and the back surface Wb of the substrate W.

[0029] The substrate support 11 further includes at least one gas hole 11h and at least one insulating member 14. In one embodiment, the substrate support 11 includes a plurality of gas holes 11h and a plurality of insulating members 14, as shown in FIG.

[0030] Each of the gas holes 11h is provided to supply a heat transfer gas (e.g., helium gas) from a heat transfer gas supply unit 36 ​​to the gap G. Each of the gas holes 11h extends upward from the base 1110 through the electrostatic chuck 1111 and opens at the upper surface of the electrostatic chuck 1111. As shown in FIG. 4A , the gas holes 11h may be arranged along one or more concentric circles centered on the axis AX, which is the central axis of the substrate support unit 11. The gas holes 11h arranged along each concentric circle may be disposed at equal intervals. Note that although the number of concentric circles is two in FIG. 4 , the number of concentric circles is not limited to two.

[0031] 3, in one embodiment, each of the plurality of gas holes 11h may be provided by a sleeve 16 within the base 1110. The sleeve 16 has a tubular shape and may be made of an insulating material such as aluminum oxide.

[0032] The insulating members 14 are respectively disposed in the gas holes 11h. Each of the insulating members 14 has insulating properties, is rod-shaped, and extends upward within the gas holes 11h. Each of the insulating members 14, together with the corresponding gas hole 11h, forms a gas flow path for supplying heat transfer gas to the gap G. The insulating members 14 can reduce the occurrence of discharge within the gas holes 11h and in the gap G.

[0033] In one embodiment, each of the multiple insulating members 14 may include a first portion 14a and a second portion 14b. Each of the first portion 14a and the second portion 14b is rod-shaped. The first portion 14a extends upward within a corresponding gas hole 11h extending within the base 1110. The second portion 14b is provided on the first portion 14a. The second portion 14b extends upward within a corresponding gas hole 11h extending within the electrostatic chuck 1111. The first portion 14a may be made of a resin material such as polytetrafluoroethylene. The second portion 14b may be made of a ceramic such as silicon carbide.

[0034] The electrostatic chuck 1111 includes a dielectric portion 150 and a first electrode 151. The dielectric portion 150 may be made of the ceramic member 1111a described above. In one embodiment, the dielectric portion 150 has a substantially disk shape. The dielectric portion 150 has an axis line AX as its central axis line.

[0035] The first electrode 151 is the electrostatic electrode 1111b described above, and is disposed in the dielectric portion 150. The first electrode 151 may be a film formed from a metal. The first electrode 151 may have a substantially circular shape and may have the axis AX as its central axis.

[0036] The electrostatic chuck 1111 further includes at least one second electrode 152. The number of second electrodes 152 may be the same as the number of gas holes 11h. In one embodiment, the electrostatic chuck 1111 includes a plurality of second electrodes 152. Each of the plurality of second electrodes 152 may be a film formed of a metal. Each of the plurality of second electrodes 152 is disposed in the dielectric portion 150 and extends between the first electrode 151 and the insulating member 14 (or the second portion 14b) in the corresponding gas hole 11h, surrounding the insulating member 14 (or the second portion 14b). Each of the plurality of second electrodes 152 is spaced apart from the first electrode 151. Furthermore, each of the plurality of second electrodes 152 is spaced apart from the plane defining the corresponding gas hole 11h. Each of the plurality of second electrodes 152 may have a ring shape.

[0037] The plasma processing apparatus 1 further includes at least one power supply 34. The at least one power supply 34 is electrically connected to the first electrode 151 and the plurality of second electrodes 152. The at least one power supply 34 may include a DC power supply. The at least one power supply 34 applies a positive voltage (e.g., a DC voltage) to the first electrode 151. When the positive voltage is applied to the first electrode 151, the above-mentioned electrostatic attraction force is generated. The substrate W is attracted to the electrostatic chuck 1111 by the electrostatic attraction force and held by the electrostatic chuck 1111.

[0038] At least one power supply 34 applies a voltage (e.g., a DC voltage) to each of the multiple second electrodes 152, independently of the application of a positive voltage to the first electrode 151. In the example of FIG. 3 , the at least one power supply 34 includes a power supply 34a (first power supply) and a power supply 34b (second power supply). Each of the power supplies 34a and 34b may be a DC power supply. The power supply 34a is connected to the first electrode 151 via a switch and is configured to apply a positive voltage to the first electrode 151 to generate the above-mentioned electrostatic attraction. The power supply 34b is electrically connected to the multiple second electrodes 152 via a switch and is configured to apply a voltage to the multiple second electrodes 152. Note that the at least one power supply 34 may include two or more power supplies 34b for applying a voltage to the multiple second electrodes 152.

[0039] According to the plasma processing apparatus 1, it is possible to apply a voltage to the plurality of second electrodes 152 from at least one power source 34 independently of the application of a positive voltage to the first electrode 151. Therefore, it is possible to adjust the voltage applied to the plurality of second electrodes 152 so as to suppress discharge in the plurality of gas holes 11h and the gap G independently of the positive voltage applied to the first electrode 151.

[0040] In one embodiment, the voltage applied to the first electrode 151 from the at least one power supply 34 and the voltage applied to each of the plurality of second electrodes 152 from the at least one power supply 34 may be different from each other.

[0041] 5 is a diagram showing an example of a substrate support and a power supply employed in a plasma processing apparatus according to an exemplary embodiment. In one example, as shown in FIG. 5 , a positive voltage (e.g., a DC voltage) is applied to the first electrode 151 from at least one power supply 34 (or power supply 34 a). A negative voltage (e.g., a DC voltage) is applied to each of the multiple second electrodes 152 from at least one power supply 34 (or power supply 34 b). In this case, as shown in FIG. 5 , the areas around the multiple second electrodes 152 and the insulating member 14 (or second portion 14 b) within the entire area of ​​the dielectric portion 150 are negatively charged, and above them, the back surface Wb of the substrate W is positively charged. Therefore, emission of primary electrons from the back surface Wb of the substrate W is suppressed, and discharge in the multiple gas holes 11 h and the gap G is suppressed.

[0042] Furthermore, even when the secondary electron emission coefficient of the material constituting the back surface Wb of the substrate W is higher than that of the material constituting the insulating member 14 (or the second portion 14b), a negative voltage (e.g., a DC voltage) may be applied to the multiple second electrodes 152 from at least one power supply 34 (or power supply 34b). In this case, too, a positive voltage (e.g., a DC voltage) is applied to the first electrode 151 from at least one power supply 34 (or power supply 34a). In this case, too, the areas around the multiple second electrodes 152 and the insulating member 14 (or the second portion 14b) within the entire area of ​​the dielectric portion 150 are negatively charged, and above them, the back surface Wb of the substrate W is positively charged. Therefore, the emission of secondary electrons from the back surface Wb of the substrate W is suppressed, and discharge in the multiple gas holes 11h and the gap G is suppressed.

[0043] 6 is a diagram illustrating an example of a substrate support and a power supply employed in a plasma processing apparatus according to an exemplary embodiment. When the secondary electron emission coefficient of the material constituting the back surface Wb of the substrate W is lower than that of the material constituting the insulating member 14 (or the second portion 14b), a positive voltage (e.g., a DC voltage) may be applied to the plurality of second electrodes 152 from at least one power supply 34 (or power supply 34b), as shown in FIG. 6 . In this case, a positive voltage (e.g., a DC voltage) is also applied to the first electrode 151 from at least one power supply 34 (or power supply 34a). In this case, the regions around the plurality of second electrodes 152 and the insulating member 14 (or the second portion 14b) within the entire area of ​​the dielectric portion 150 are positively charged. Therefore, the emission of secondary electrons from the area surrounding the multiple second electrodes 152 and the insulating member 14 (or the second portion 14b) in the entire area of ​​the dielectric portion 150 is suppressed, and discharge in the multiple gas holes 11h and the gap G is suppressed.

[0044] Reference is now made to FIG. 7 , which illustrates an example of a substrate support and power supplies employed in a plasma processing apparatus according to an exemplary embodiment. As illustrated in FIG. 7 , the at least one power supply 34 may include a single power supply 34 a. In this case, the output (e.g., positive terminal) of the power supply 34 a is electrically connected to the first electrode 151 via a switch, and is also electrically connected to the plurality of second electrodes 152 via a DC / DC converter 34 c. The DC / DC converter 34 c allows a voltage independent of the voltage applied to the first electrode 151 to be generated based on the voltage output from the single power supply 34 a and applied to the plurality of second electrodes 152.

[0045] In the plasma processing apparatus 1 , at least one power supply 34 and the above-mentioned switches can be controlled by the control unit 2 .

[0046] A plasma processing method according to one exemplary embodiment will be described below with reference to Fig. 8. Fig. 8 is a flow chart showing the plasma processing method according to one exemplary embodiment. The plasma processing method shown in Fig. 8 (hereinafter referred to as "method MT") can be performed using a plasma processing apparatus 1. In method MT, each part of the plasma processing apparatus 1 can be controlled by a control unit 2.

[0047] 8, the method MT starts with step STa, in which a substrate W is placed on an electrostatic chuck 1111.

[0048] In the subsequent step STb, plasma is generated in the chamber 10. In step STb, the control unit 2 controls the gas supply unit 20 to supply a process gas into the chamber 10, and controls the exhaust system 40 to control the pressure in the chamber 10 to a designated pressure. The control unit 2 also controls the plasma generation unit 12 to generate plasma from the process gas in the chamber 10. For example, the control unit 2 controls the first RF generation unit 31a to supply a source RF signal (source RF power) to generate plasma.

[0049] In addition, in the process STc, a voltage is applied from at least one power supply 34 to the first electrode 151 to generate an electrostatic attraction force between the electrostatic chuck 1111 and the substrate W. In the process STc, the at least one power supply 34 can be controlled by the control unit 2.

[0050] Step STd is performed during the period in which step STc is being performed. In step STd, a voltage is applied to the second electrode 152 (or a plurality of second electrodes 152) from at least one power source 34. In step STd, the at least one power source 34 can be controlled by the control unit 2.

[0051] Step STe is performed during the period when steps STb, STc, and STd are being performed. In step STe, a heat transfer gas is supplied to the gap G from the gas hole 11h (or a plurality of gas holes 11h). In step STe, the control unit 2 controls the heat transfer gas supply unit 36.

[0052] In the method MT, in step STc, the substrate W held by the electrostatic chuck 1111 is processed by the plasma generated in step STb. The substrate W is, for example, etched by chemical species from the plasma. In steps STc and STd, the at least one power supply 34 can be controlled by the controller 2 to apply independent voltages to the first electrode 151 and each second electrode 152.

[0053] In one embodiment, the voltage applied to the first electrode 151 from at least one power source 34 in process STc and the voltage applied to each second electrode 152 from at least one power source 34 in process STd may be different from each other.

[0054] 5, a positive voltage (e.g., a DC voltage) may be applied to the first electrode 151 in step STc, and a negative voltage (e.g., a DC voltage) may be applied to each second electrode 152 in step STd. In another example, a positive voltage (e.g., a DC voltage) may be applied to the first electrode 151 in step STc, and a positive voltage (e.g., a DC voltage) may be applied to each second electrode 152 in step STd, as described above with reference to FIG.

[0055] Examples of processing circuits that can be used as one or more processing circuits in the plasma processing apparatus 1, such as the control unit 2, are described below. FIG. 9 is a block diagram of a processing circuit that performs the operations described herein on a computer. FIG. 9 illustrates a processing circuit 130 that can be used to control a control process on any computer. The descriptions or blocks in the flowcharts represent modules, segments, or portions of code that include one or more executable instructions for implementing specific logical functions or steps of the process. As will be understood by those skilled in the art, other examples having functions that can be performed in a different order than that shown or described, such as substantially simultaneously or in reverse order, depending on the functionality involved, are included within the scope of exemplary embodiments of the present disclosure. The various elements, features, and processes described herein may be used independently of each other or combined in various ways. All conceivable combinations and subcombinations are within the scope of the present disclosure.

[0056] In Figure 9, processing circuitry 130 includes a CPU 1200 that performs one or more of the control processes described above and / or below. Process data and instructions may be stored in memory 1202. These process data and instructions may be stored on a storage medium disk 1204, such as a hard disk drive (HDD) or a portable storage medium, or may be stored remotely. Furthermore, the present disclosure as claimed is not limited by the form of computer-readable medium on which instructions for processes according to the present invention are stored. For example, these instructions may be stored on a CD, DVD, flash memory, RAM, ROM, PROM, EPROM, EEPROM, hard disk, or any other information processing device, such as a server and / or computer, with which processing circuitry 130 communicates.

[0057] Furthermore, the claimed disclosure may be provided as a utility application, a background daemon, a component of an operating system, or a combination thereof, and may execute in conjunction with CPU 1200 and an operating system known to those skilled in the art, such as Microsoft Windows®, UNIX®, Solaris®, LINUX®, Apple MAC-OS, etc.

[0058] The hardware elements making up the processing circuit 130 can be realized by various circuit elements. Furthermore, each function of the above-described embodiments can be implemented by a circuit including one or more processing circuits. As shown in FIG. 9, the processing circuit includes a specifically programmed processing unit, such as a processing unit (CPU) 1200. The processing circuit also includes devices such as application specific integrated circuits (ASICs) or conventional circuit components configured to perform the described functions.

[0059] 9, processing circuitry 130 includes a CPU 1200 that performs the above-described processing. Processing circuitry 130 may be a general-purpose computer or a specialized machine. In one embodiment, processing circuitry 130 functions as a specialized machine when processing device 1200 is programmed to control components of plasma processing device 1, such as gas supply 20, power supply 30, at least one power supply 34, and the switches described above.

[0060] Alternatively or additionally, CPU 1200 may be implemented on an FPGA, ASIC, PLD, or using discrete logic circuitry, as will be appreciated by those skilled in the art. Furthermore, CPU 1200 may be implemented as multiple processing units cooperating to perform in parallel the instructions of the processes of the present invention described above.

[0061] The processing circuitry 130 of FIG. 9 also includes a network controller 1206, such as an Intel Ethernet PRO network interface card from Intel Corporation of America, for interfacing with a network 1228. As can be appreciated, the network 1228 may be a public network, such as the Internet, a private network, such as a LAN or WAN, or any combination thereof, and may include sub-networks, such as a PSTN or ISDN. The network 1228 may also be wired, such as an Ethernet network, or wireless, such as a cellular network, including EDGE, 3G, and 4G wireless cellular systems. The wireless network may also be Wi-Fi, Bluetooth, or any other known form of wireless communication.

[0062] The processing circuitry 130 further includes a display device controller 1208, such as a graphics card or graphics adapter, for interfacing with a display device 1210, such as a monitor. A general-purpose I / O interface 1212 interfaces with a keyboard and / or mouse 1214 and a touch panel 1216, which may be integral with or separate from the display device 1210. The general-purpose I / O interface also connects to various peripheral devices 1218, such as printers and scanners.

[0063] The storage controller 1224 is connected to the storage media disk 1204 via a communication bus 1226, such as ISA, EISA, VESA, PCI, etc., and all components of the processing circuit 130 are connected to each other. The display device 1210, keyboard and / or mouse 1214, and the general features and functions of the display device controller 1208, storage controller 1224, network controller 1206, audio controller 1220, and general purpose I / O interface 1212 are not described herein for the sake of brevity, as they are well known.

[0064] The exemplary circuit elements described in this disclosure may be substituted with other elements and may have different structures than the examples described herein. Furthermore, circuits configured to implement the features described herein may be implemented in multiple circuit units (e.g., chips), or these features may be combined into the circuitry of a single chipset.

[0065] The functions and features described herein may also be performed by various distributed components on a system. For example, one or more processing devices may perform the functions of these systems, where the processing devices are distributed across multiple components communicating within a network. Distributed components may include various human interface and communication devices (e.g., display monitors, smartphones, tablets, personal digital assistants (PDAs)), as well as one or more client and server machines that can share processing. The network may be a private network, such as a LAN or WAN, or a public network, such as the Internet. Input to the system may be received directly by a user or remotely in real time or as a batch process. Furthermore, portions of the embodiments may be implemented on modules or hardware other than those described above. Accordingly, other embodiments are within the scope of the claims.

[0066] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0067] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims.

[0068] 1...plasma processing apparatus, 10...chamber, 11...substrate support portion, 12...plasma generation portion, 1110...base, 1111...electrostatic chuck, 150...dielectric portion, 151...first electrode, 152...second electrode, 14...insulating member, 34...power supply.

Claims

1. A plasma processing apparatus comprising: a chamber; a substrate support portion having an electrostatic chuck and disposed within the chamber; a plasma generation portion configured to generate plasma from a gas within the chamber; and at least one power supply connected to the substrate support portion, wherein the substrate support portion includes: gas holes opening in an upper surface of the electrostatic chuck for supplying a heat transfer gas to a gap between the electrostatic chuck and a backside of the substrate; and an insulating member disposed within the gas holes, wherein the electrostatic chuck includes: a dielectric portion; a first electrode disposed within the dielectric portion for attracting the substrate to the electrostatic chuck by electrostatic attraction; and a second electrode extending within the dielectric portion and between the first electrode and the insulating member to surround the insulating member, wherein the at least one power supply is electrically connected to the first electrode and the second electrode to apply independent voltages to each of the first electrode and the second electrode.

2. The plasma processing apparatus according to claim 1, wherein the voltage applied to the first electrode from the at least one power supply and the voltage applied to the second electrode from the at least one power supply are different from each other.

3. The plasma processing apparatus of claim 2, wherein said at least one power supply is configured to apply a positive voltage to said first electrode and a negative voltage to said second electrode.

4. The plasma processing apparatus according to claim 2, wherein the secondary electron emission coefficient of the material constituting the rear surface of the substrate is higher than the secondary electron emission coefficient of the material constituting the insulating member, and the at least one power source is configured to apply a positive voltage to the first electrode and a negative voltage to the second electrode.

5. The plasma processing apparatus according to claim 2, wherein the secondary electron emission coefficient of the material constituting the rear surface of the substrate is lower than the secondary electron emission coefficient of the material constituting the insulating member, and the at least one power source is configured to apply a positive voltage to the first electrode and a positive voltage to the second electrode.

6. The plasma processing apparatus according to any one of claims 1 to 5, wherein the at least one power supply is a DC power supply.

7. A plasma processing apparatus according to any one of claims 1 to 5, wherein the at least one power supply includes: a first power supply connected to the first electrode; and a second power supply connected to the second electrode.

8. The plasma processing apparatus according to claim 7, wherein each of the first power supply and the second power supply is a DC power supply.

9. The plasma processing apparatus according to any one of claims 1 to 5, wherein the at least one power supply includes: a single power supply having a positive pole connected to the first electrode; and a DC / DC converter connected between the positive pole and the second electrode.

10. The plasma processing apparatus of claim 9, wherein the single power supply is a DC power supply.

11. A plasma processing method comprising: a step of placing a substrate on an electrostatic chuck of a substrate support part in a chamber of a plasma processing apparatus, wherein the substrate support part includes a gas hole opening in an upper surface of the electrostatic chuck and an insulating member disposed in the gas hole, and the electrostatic chuck includes a dielectric part, a first electrode in the dielectric part, and a second electrode extending in the dielectric part and between the first electrode and the insulating member so as to surround the insulating member; a step of generating plasma in the chamber; a step of applying a voltage from at least one power supply to the first electrode to generate an electrostatic attraction between the electrostatic chuck and the substrate; a step of applying a voltage from the at least one power supply to the second electrode during the step of applying a voltage to the first electrode; and a step of supplying a heat transfer gas from the gas hole to a gap between the electrostatic chuck and the back surface of the substrate, wherein the at least one power supply applies independent voltages to the first electrode and the second electrode.

12. The plasma processing method according to claim 11, wherein the voltage applied to the first electrode from the at least one power supply and the voltage applied to the second electrode from the at least one power supply are different from each other.

13. The plasma processing method according to claim 12, wherein the voltage applied to the first electrode is a positive voltage, and the voltage applied to the second electrode is a negative voltage.

14. The plasma processing method according to claim 12, wherein the secondary electron emission coefficient of the material constituting the rear surface of the substrate is higher than the secondary electron emission coefficient of the material constituting the insulating member, the voltage applied to the first electrode is a positive voltage, and the voltage applied to the second electrode is a negative voltage.

15. The plasma processing method according to claim 12, wherein the secondary electron emission coefficient of the material constituting the rear surface of the substrate is lower than the secondary electron emission coefficient of the material constituting the insulating member, the voltage applied to the first electrode is a positive voltage, and the voltage applied to the second electrode is a positive voltage.

16. The plasma processing method according to any one of claims 11 to 15, wherein the voltage applied to the first electrode and the voltage applied to the second electrode from the at least one power supply are each a DC voltage.

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