Plasma processing apparatus and plasma processing method

Abstract

In the plasma processing apparatus of the present invention, a first processing condition including supplying a first processing gas into a chamber and a second processing condition including supplying a second processing gas into the chamber are respectively applied in a first processing period and a second processing period. In each of the first processing period and the second processing period, a source high-frequency electric power is supplied to generate plasma, and an electric bias is supplied to the substrate supporting part. In the first processing period, a plurality of frequencies of the first frequency set are used in sequence as the frequencies of the source high-frequency electric power in the waveform period of the electric bias. In the second processing period, a plurality of frequencies of the second frequency set are used in sequence as the frequencies of the source high-frequency electric power in the waveform period of the electric bias.

Description

Technical Field

[0001] Exemplary embodiments of the present invention relate to a plasma processing apparatus and a plasma processing method. Background Art

[0002] A plasma processing device is used for plasma processing of a substrate. In the plasma processing device, bias high-frequency electric power is used to attract ions from plasma generated in a chamber to the substrate. Patent document 1 below discloses a plasma processing device capable of modulating the power level and frequency of the bias high-frequency electric power.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2009-246091 Summary of the invention

[0006] Technical problem to be solved by the invention

[0007] The present invention provides a technology capable of reducing the degree of reflection of source high-frequency electric power.

[0008] Means for solving technical problems

[0009] In an exemplary embodiment, a plasma processing device is provided. The plasma processing device includes a chamber, a substrate support, a gas supply, a high-frequency power supply, and a bias power supply. The substrate support is arranged in the chamber. The gas supply can supply gas into the chamber. The high-frequency power supply can supply source high-frequency electric power to generate plasma from the gas in the chamber. The bias power supply is electrically coupled to the substrate support and can generate an electric bias. During the first processing period, the high-frequency power supply uses a plurality of frequencies included in the first frequency set as the source frequency of the source high-frequency electric power used for each of the multiple phases in the waveform period of the electric bias, wherein the first frequency set is determined to suppress the degree of reflection of the source high-frequency electric power from the load. During the first processing period, a first processing condition is applied, and the first processing condition includes supplying the first processing gas from the gas supply into the chamber. During the second processing period, the high-frequency power supply uses a plurality of frequencies included in the second frequency set as the source frequency of the source high-frequency electric power used for each of the multiple phases in the waveform period of the electric bias, wherein the second frequency set is determined to suppress the degree of reflection of the source high-frequency electric power from the load. During the second process period, a second process condition is applied, and the second process condition includes supplying a second process gas from the gas supply unit into the chamber.

[0010] Effects of the Invention

[0011] According to an exemplary embodiment, the degree of reflection of source high frequency electric power can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a diagram for explaining a configuration example of a plasma processing system.

[0013] Figure 2 This is a diagram for explaining a configuration example of a capacitive coupling type plasma processing apparatus.

[0014] Figure 3 FIG. 1 is a diagram showing a configuration example of a power supply system in a plasma processing apparatus according to an exemplary embodiment.

[0015] Figure 4 is a timing chart showing an example of an electrical bias used in a plasma processing apparatus according to an exemplary embodiment.

[0016] Figure 5 FIG. 1 is a timing chart showing an example of an electric bias and a source frequency of a source high-frequency electric power used in a plasma processing apparatus according to an exemplary embodiment.

[0017] Figure 6 is a timing diagram associated with a plasma processing apparatus according to an exemplary embodiment.

[0018] Figure 7 (a) Figure 7 (b) and Figure 7 (c) are diagrams each showing a pulse period in a pulse period sequence related to a plasma processing apparatus according to an exemplary embodiment.

[0019] Figure 8 is a flow chart of a plasma processing method according to an exemplary embodiment. DETAILED DESCRIPTION

[0020] Hereinafter, various exemplary embodiments will be described in detail with reference to the accompanying drawings. In addition, in each of the drawings, the same reference numerals are given to the same or corresponding parts.

[0021] Figure 1: is a diagram for illustrating a structural example of a plasma processing system. In one embodiment, the plasma processing system includes a plasma processing device 1 and a control unit 2. The plasma processing system is an example of a substrate processing system, and the plasma processing device 1 is an example of a substrate processing device. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support portion 11, and a plasma generating portion 12. The plasma processing chamber 10 has a plasma processing space. In addition, the plasma processing chamber 10 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 the gas supply portion 20 described later, and the gas exhaust port is connected to the exhaust system 40 described later. The substrate support portion 11 is arranged in the plasma processing space and has a substrate supporting surface for supporting a substrate.

[0022] The plasma generating unit 12 can generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space can be capacitively coupled plasma (CCP: Capacitively Coupled Plasma), inductively coupled plasma (ICP: Inductively Coupled Plasma), ECR plasma (Electron-Cyclotron-Resonance Plasma: Electron Cyclotron Resonance Plasma), helicon wave plasma (HWP: Helicon Wave Plasma) or surface wave plasma (SWP: Surface Wave Plasma), etc.

[0023] The control unit 2 is capable of processing computer-executable commands, which are used to cause the plasma processing device 1 to perform various processes described in the present invention. The control unit 2 is capable of controlling the various elements of the plasma processing device 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 device 1. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The control unit 2 is implemented, for example, by a computer 2a. The processing unit 2a1 is capable of reading a program from the storage unit 2a2 and performing various control actions by executing the read program. The program may be pre-stored in the storage unit 2a2 or acquired via a medium when necessary. The acquired program is stored in the storage unit 2a2 and is read and executed from the storage unit 2a2 by the processing unit 2a1. 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 RAM (Random Access Memory), a ROM (Read Only Memory), a HDD (Hard Disk Drive), an SSD (Solid State Drive), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing device 1 via a communication line such as a LAN (Local Area Network).

[0024] Next, a configuration example of a capacitive coupling type plasma processing apparatus will be described as an example of the plasma processing apparatus 1 . Figure 2 This is a diagram for explaining a configuration example of a capacitive coupling type plasma processing apparatus.

[0025] A capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply system 30, and an exhaust system 40. In addition, the plasma processing apparatus 1 includes a substrate support unit 11 and a gas introduction unit. The gas introduction unit is capable of introducing at least one processing gas into the plasma processing chamber 10. The gas introduction unit includes a shower head 13. The substrate support unit 11 is disposed in the plasma processing chamber 10. The shower head 13 is disposed above the substrate support unit 11. In one embodiment, the shower head 13 constitutes 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 shower head 13, the side wall 10a of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 is grounded. The substrate support unit 11 is electrically insulated from the shell of the plasma processing chamber 10.

[0026] The substrate support portion 11 includes a main body 111 and a ring assembly 112. The main body 111 has: a central area 111a for supporting a substrate W; and an annular area 111b for supporting the ring assembly 112. A wafer is an example of a substrate W. The annular area 111b of the main body 111 surrounds the central area 111a of the main body 111 when viewed from above. The substrate W is arranged on the central area 111a of the main body 111, and the ring assembly 112 is arranged on the annular area 111b of the main body 111 in a manner surrounding the substrate W on the central area 111a of the main body 111. Therefore, the central area 111a is also referred to as a substrate support surface for supporting the substrate W, and the annular area 111b is also referred to as a ring support surface for supporting the ring assembly 112.

[0027] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive component. The electrostatic chuck 1111 is arranged on the base 1110. The electrostatic chuck 1111 includes a ceramic component 1111a and an electrostatic electrode 1111b arranged in the ceramic component 1111a. The ceramic component 1111a has a central area 111a. In one embodiment, the ceramic component 1111a also has an annular area 111b. In addition, other components surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating component, may have an annular area 111b. In this case, the ring assembly 112 may be arranged on the annular electrostatic chuck or the annular insulating component, or may be arranged on both the electrostatic chuck 1111 and the annular insulating component.

[0028] The ring assembly 112 includes one or more ring-shaped components. In one embodiment, the one or more ring-shaped components 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.

[0029] In addition, the substrate support portion 11 may include a temperature regulating module capable of regulating at least one of the electrostatic chuck 1111, the ring assembly 112 and the substrate to a target temperature. The temperature regulating module may include a heater, a heat transfer medium, a flow path 1110a or a combination thereof. A heat transfer fluid such as salt water or gas may flow in the flow path 1110a. In one embodiment, the flow path 1110a is formed in the base 1110, and one or more heaters are arranged in the ceramic component 1111a of the electrostatic chuck 1111. In addition, the substrate support portion 11 may include a heat transfer gas supply portion capable of supplying a heat transfer gas to the gap between the back side of the substrate W and the central area 111a.

[0030] The shower head 13 can introduce at least one processing gas from the gas supply part 20 into the plasma processing space 10s. The shower head 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b and multiple gas introduction ports 13c. The processing gas supplied to the gas supply port 13a can be introduced into the plasma processing space 10s from the multiple gas introduction ports 13c through the gas diffusion chamber 13b. In addition, the shower head 13 includes at least one upper electrode. In addition, the gas introduction part may include, in addition to the shower head 13, one or more side gas injection parts (SGI: Side Gas Injector) installed in one or more openings formed on the side wall 10a.

[0031] 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 capable of supplying at least one process gas from the gas source 21 corresponding to each other to the shower head 13 via the flow controller 22 corresponding to each other. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Furthermore, the gas supply unit 20 may include at least one flow modulation device for modulating or pulsing the flow of at least one process gas.

[0032] The exhaust system 40 can be connected to the gas exhaust port 10e provided at the bottom of the plasma processing chamber 10, for example. The exhaust system 40 can include a pressure regulating valve and a vacuum pump. The pressure in the plasma processing space 10s can be adjusted by the pressure regulating valve. The vacuum pump can include a turbomolecular pump, a dry pump, or a combination thereof.

[0033] Below, with Figure 2 Refer to Figure 3 . Figure 3 1 is a diagram showing a configuration example of a power supply system in a plasma processing apparatus according to an exemplary embodiment. The power supply system 30 includes a high-frequency power supply 31 and a bias power supply 32. The high-frequency power supply 31 constitutes a plasma generating unit 12 according to an embodiment. The high-frequency power supply 31 can generate a source high-frequency electric power HF. The source high-frequency electric power HF has a source frequency f HF . Source frequency f HF The frequency may be in the range of 10 MHz to 150 MHz. The power level of the source high frequency electric power HF or its pulse HFP described later can be specified by the control unit 2 to the high frequency power source 31 .

[0034] The high frequency power supply 31 can supply source high frequency electric power HF to the high frequency electrode. The high frequency electrode can be arranged in the substrate support part 11. The high frequency electrode can be a conductive component of the base 1110 or at least one electrode arranged in the ceramic component 1111a. Alternatively, the high frequency electrode can also be an upper electrode. When the source high frequency electric power HF is supplied to the high frequency electrode, plasma can be generated from the gas in the chamber 10.

[0035] The high frequency power source 31 is electrically connected to the high frequency electrode via a matching device 33. The matching device 33 has a variable impedance. The variable impedance of the matching device 33 is set to reduce reflection of the source high frequency electric power HF of the load from the high frequency power source 31. The matching device 33 can be controlled by the control unit 2, for example.

[0036] In one embodiment, the high frequency power source 31 may include a signal generator 31g, a D / A converter 31c, and an amplifier 31a. The signal generator 31g is capable of generating a signal having a source frequency f HF The signal generator 31g can be composed of a programmable processor or a programmable logic device such as an FPGA (Field-Programmable Gate Array). The signal generator 31g can be composed of a single programmable device together with the signal generator 32g described later, or can be composed of a different programmable device from the signal generator 32g.

[0037] The output of the signal generator 31g is connected to the input of the D / A converter 31c. The D / A converter 31c can convert the high-frequency signal from the signal generator 31g into an analog signal. The output of the D / A converter 31c is connected to the input of the amplifier 31a. The amplifier 31a can amplify the analog signal from the D / A converter 31c to generate the source high-frequency electric power HF. The amplification factor of the amplifier 31a can be specified to the high-frequency power supply 31 from the control unit 2. In addition, the high-frequency power supply 31 may not include the D / A converter 31c. In this case, the output of the signal generator 31g is connected to the input of the amplifier 31a, and the amplifier 31a amplifies the high-frequency signal from the signal generator 31g to generate the source high-frequency electric power HF. Alternatively, the amplifier 31a can also directly receive the frequency information from the signal generator 31g and generate the source high-frequency electric power HF having the source frequency determined from the frequency information.

[0038] The bias power supply 32 is electrically coupled to the substrate support portion 11. The bias power supply 32 is electrically connected to the bias electrode in the substrate support portion 11, and can supply an electric bias EB to the bias electrode. The bias electrode can be a conductive component of the base 1110 or at least one electrode provided in the ceramic component 1111a. The bias electrode can also be shared with the high-frequency electrode. When the electric bias EB is supplied to the bias electrode, ions from the plasma can be attracted to the substrate W.

[0039] In one embodiment, the bias power supply 32 may be Figure 3 As shown, the signal generator 32g includes a signal generator 32g, a D / A converter 32c and an amplifier 32a. The signal generator 32g can generate a bias signal having a specified waveform. The signal generator 32g can be composed of a programmable processor or a programmable logic device such as an FPGA.

[0040] The output of the signal generator 32g is connected to the input of the D / A converter 32c. The D / A converter 32c can convert the bias signal from the signal generator 32g into an analog signal. The output of the D / A converter 32c is connected to the input of the amplifier 32a. The amplifier 32a can amplify the analog signal from the D / A converter 32c to generate the electrical bias EB. The amplification factor of the amplifier 32a can be specified from the control unit 2 to the bias power supply 32. In addition, the bias power supply 32 may not include the D / A converter 32c. In this case, the output of the signal generator 32g is connected to the input of the amplifier 32a, and the amplifier 32a generates the electrical bias EB from the voltage waveform or electric power information of the bias signal from the signal generator 32g.

[0041] Below, with Figure 2 and Figure 3 Refer to Figure 4 . Figure 4 1 is a timing diagram showing an example of an electrical bias used in a plasma processing apparatus according to an exemplary embodiment. The electrical bias EB or its pulse EBP described later, such as Figure 4 As shown, the electric bias EB has a waveform period CY and is periodically supplied to the bias electrode from the bias power supply 32. The waveform period CY of the electric bias EB is determined by the bias frequency. The bias frequency is, for example, a frequency of 100 kHz to 50 MHz. The time length of the waveform period CY of the electric bias EB is the inverse of the bias frequency.

[0042] The electrical bias EB can be Figure 4 As shown in FIG. 1 , the bias high frequency electric power LF is biased. That is, the electric bias EB may have a waveform having a sine wave shape whose frequency is the bias frequency. In this case, the bias power supply 32 is electrically connected to the bias electrode via the matching device 34. The variable impedance of the matching device 34 is set to reduce the reflection of the bias high frequency electric power LF from the load.

[0043] Alternatively, the electrical bias EB may also be a sequence of voltage pulses. The sequence of voltage pulses includes periodically generated voltage pulses PV. The voltage pulses PV are applied to the bias electrode within a waveform period CY. The voltage pulses PV are periodically applied to the bias electrode at time intervals of the same length as the time length of the waveform period CY. The waveform of the voltage pulse PV may be a rectangular wave, a triangular wave, or an arbitrary waveform. The polarity of the voltage of the voltage pulse PV is set so as to generate a potential difference between the substrate W and the plasma to attract ions from the plasma to the substrate W. The voltage pulse PV may be a pulse of a negative voltage or a pulse of a negative direct current voltage. In the case where the electrical bias EB includes a sequence of voltage pulses PV, the plasma processing device 1 may not include a matcher 34.

[0044] The level of the electric bias EB or its pulse EBP can be specified from the control unit 2 to the bias power supply 32. When the electric bias EB or its pulse EBP is the bias high-frequency electric power LF, the level of the electric bias EB or its pulse EBP is the power level of the bias high-frequency electric power LF. When the electric bias EB or its pulse is a voltage pulse sequence, the level of the electric bias EB or its pulse EBP is the magnitude in the negative direction of the voltage level of the voltage pulse PV relative to the reference voltage level (e.g., 0V). The level of the electric bias EB or its pulse EBP can also be the absolute value of the negative voltage level of the voltage pulse PV.

[0045] Figure 5 FIG. 1 is a timing diagram showing an example of an electric bias and a source frequency of a source high frequency electric power used in a plasma processing apparatus according to an exemplary embodiment. Figure 5 As shown in FIG. 1 , the high-frequency power supply 31 can change the source frequency within the waveform period CY of the electric bias EB so as to suppress the degree of reflection of the source high-frequency electric power HF from the load. In the plasma processing device 1, the waveform period CY of the electric bias EB is divided into a plurality of phase periods SP. The high-frequency power supply 31 changes the source frequency during the plurality of phase periods SP by using a plurality of source frequencies for each of the plurality of phase periods SP. The change of the source frequency within the waveform period CY of the electric bias EB will be described later.

[0046] Below, with Figure 2 to Figure 5 Refer to Figure 6 . Figure 6 is a timing diagram related to a plasma processing apparatus according to an exemplary embodiment. The high frequency power source 31 may be as follows: Figure 6As shown, a pulse HFP of source high-frequency electric power HF can be generated and supplied to the high-frequency electrode. The pulse HFP can be supplied repeatedly. The pulse HFP can also be supplied periodically. The pulse period of the pulse HFP (for example, any one of the processing periods P1 to P4 described later) and the duty ratio of the pulse HFP can be specified from the control unit 2. The pulse period of the pulse HFP (for example, each of the processing periods P1 to P4 described later) includes a period (ON period) when the pulse HFP is in the ON (or high power level) state and a period (OFF period) when the pulse HFP is in the OFF (or low power level) state. The duty ratio of the pulse HFP is the ratio of the period when the pulse HFP is in the ON (or high power level) state to the pulse period of the pulse HFP.

[0047] The bias power supply 32 may be Figure 4 and Figure 6 As shown in FIG. 1 , a pulse EBP that can generate an electric bias EB and supply it to the bias electrode. The pulse EBP can be supplied repeatedly. The pulse EBP can also be supplied periodically. The pulse period of the pulse EBP (for example, any one of the processing periods P1 to P4 described later) and the duty ratio of the pulse EBP can be specified by the control unit 2. The pulse period of the pulse EBP (for example, each of the processing periods P1 to P4 described later) includes a period during which the pulse EBP is set to ON (ON period P ON ) and the period set to OFF (OFF period P OFF ). The duty cycle of the pulse EBP is the ON period P ON The proportion of the pulse duration of the pulse EBP.

[0048] In the plasma processing apparatus 1, a plurality of mutually different processing conditions are respectively set during a plurality of processing periods (for example, Figure 6 The plasma processing apparatus 1 is applied to the substrate W in the processing periods P1 to P4. The processing plan data for determining the plurality of processing conditions and the plurality of processing periods may be stored in the storage unit 2a2 of the control unit 2. The control unit 2 controls the various parts of the plasma processing apparatus 1 according to the processing plan data so as to perform plasma processing in each of the plurality of processing periods with a corresponding processing condition among the plurality of processing conditions.

[0049] Each of the plurality of processing conditions includes supplying a processing gas different from the processing gas supplied from the gas supply unit 20 to the chamber 10 in each of the other processing conditions in the plurality of processing conditions. The plurality of processing periods includes at least a first processing period (e.g., Figure 6 The processing period P1) and the second processing period (eg Figure 6The processing gas (first processing gas) in the first processing condition applied to the substrate W in the first processing period is different from the processing gas (second processing gas) in the second processing condition applied to the substrate W in the second processing period.

[0050] Each of the plurality of process gases of each of the plurality of process conditions may include at least one gas component that is different from all gas components of each of the other process gases of the plurality of process gases. Alternatively, each of the plurality of process gases of each of the plurality of process conditions may include the same plurality of gas components as each of the other process gases, but the flow rate of at least one of the plurality of gas components may be different from the flow rate of the corresponding gas component of the other process gases.

[0051] In an example, Figure 6 As shown, the plurality of processing periods include processing periods P1 to P4. The plurality of processing gases in the plurality of processing conditions used in each of the processing periods P1 to P4 include the same plurality of gas components as the plurality of gas components of the other processing gases in the plurality of processing gases. Specifically, the plurality of processing gases in the plurality of processing conditions used in each of the processing periods P1 to P4 include C4F6 gas, C4F8 gas, O2 gas, and Ar gas. However, the flow rate of at least one of the plurality of gas components of the processing gas in each of the processing periods P1 to P4 is different from the flow rate of the corresponding gas component in the other processing periods in the processing periods P1 to P4.

[0052] Specifically, if Figure 6 As shown, the flow rate of O2 gas in process period P1 is larger than the flow rate of O2 gas in process period P2. The flow rate of C4F6 gas in process period P2 is larger than the flow rate of C4F6 gas in process period P1, and the flow rate of O2 gas in process period P2 is smaller than the flow rate of O2 gas in process period P1. The flow rate of C4F6 gas in process period P3 is smaller than the flow rate of C4F6 gas in process period P2, the flow rate of O2 gas in process period P3 is larger than the flow rate of O2 gas in process period P2, and the flow rate of Ar gas in process period P3 is larger than the flow rate of Ar gas in process period P2. The flow rate of C4F8 gas in process period P4 is larger than the flow rate of C4F8 gas in process period P3, and the flow rate of Ar gas in process period P4 is smaller than the flow rate of Ar gas in process period P3.

[0053] In addition, during the processing period P1, the shape of the mask of the substrate W can be adjusted by using the chemical species supplied from the plasma of the processing gas. During the processing period P2, a deposit containing carbon can be formed on the surface of the substrate W by using the chemical species supplied from the plasma of the processing gas. During the processing period P3, the region of the film of the substrate W exposed from the opening of the mask can be etched by using the chemical species supplied from the plasma of the processing gas. The film can be a silicon-containing film such as a silicon oxide film. During the processing period P4, the film can be overetched by using the chemical species supplied from the plasma of the processing gas.

[0054] In one embodiment, when the electric bias EB is a voltage pulse sequence, the plurality of processing conditions may further include: at least one of the power level of the source high-frequency electric power HF or pulse HFP, the level of the electric bias EB or pulse EBP, the duty cycle (ON duty cycle) of the voltage pulse PV, the bias frequency, and the pressure in the chamber 10. Alternatively, when the electric bias EB is the bias high-frequency electric power LF, the plurality of processing conditions may further include: at least one of the power level of the source high-frequency electric power HF or pulse HFP, the level of the electric bias EB or pulse EBP, the bias frequency, and the pressure in the chamber 10.

[0055] In an example, Figure 6 As shown, the power level of the pulse HFP in the process period P4 is lower than the power level of the pulse HFP in each of the process periods P1 to P3. In addition, the level of the pulse EBP in the process period P3 is higher than the level of the pulse EBP in each of the process periods P1 and P2, and the level of the pulse EBP in the process period P4 is higher than the level of the pulse EBP in the process period P3. In addition, the duty ratio of the voltage pulse PV in the process period P2 and the duty ratio of the voltage pulse PV in the process period P3 are higher than the duty ratio of the voltage pulse PV in the process period P1 and the duty ratio of the voltage pulse PV in the process period P4. In addition, the pressure in the chamber 10 in the process period P4 is higher than the pressure in the chamber 10 in each of the process periods P1 to P3.

[0056] In order to suppress the reflection of the source high-frequency electric power HF from the load, the high-frequency power source 31 uses a specific frequency set in each of the above-mentioned multiple processing periods (for example, the processing periods P1 to P4). For example, the high-frequency power source 31 uses the first frequency set in the first processing period and the second frequency set in the second processing period. The specific frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power HF from the load under the corresponding processing conditions. The specific frequency set includes multiple frequencies. The high-frequency power source 31 uses the multiple frequencies included in the specific frequency set as the source frequency for each of the multiple phase periods SP of the waveform period CY in each of the multiple processing periods.

[0057] In the plasma processing apparatus 1, the frequency set determined to suppress the degree of reflection of the source high-frequency electric power HF from the load in the multiple phase periods SP in the waveform cycle CY can be selected at least in accordance with the processing gas. Therefore, the degree of reflection of the source high-frequency electric power HF can be reduced in the multiple phase periods in the waveform cycle CY in each of two or more processing periods using different processing gases.

[0058] In one embodiment, in each of a plurality of processing periods (eg, processing periods P1 to P4), Figure 6 As shown, the pulse HFP is supplied before the pulse EBP. During the period when the pulse HFP is before the pulse EBP, the plasma is ignited. During the period when the pulse HFP is before the pulse EBP in each of the plurality of processing periods, the high frequency power supply 31 uses a predetermined source frequency for plasma ignition. The source frequency for plasma ignition can be specified to the high frequency power supply 31 from the control unit 2.

[0059] In one embodiment, the unique frequency sets used in each of the plurality of processing periods (e.g., processing periods P1 to P4) may be registered in a corresponding frequency table in a storage unit of the plasma processing apparatus 1. For example, the first frequency set and the second frequency set may be registered in the first frequency table and the second frequency table in the storage unit, respectively. The storage unit may be the storage unit 2a2 or a storage unit in the high frequency power supply 31.

[0060] In one embodiment, the bias power supply 32 may supply pulses EBP in each of a plurality of processing periods (e.g., processing periods P1 to P4). The bias power supply 32 may repeatedly supply pulses EBP in each of a plurality of pulse period sequences. Each of a plurality of pulse period sequences includes a plurality of pulse periods. The plurality of pulse periods are repetitions of corresponding processing periods in a plurality of processing periods (e.g., processing periods P1 to P4). The bias power supply 32 supplies pulses EBP in each of a plurality of pulse periods included in each of a plurality of pulse period sequences. In one example, Figure 6 As shown, the bias power supply 32 repeatedly supplies the pulse EBP in each of the four pulse period sequences which are the repetitions of the processing periods P1 to P4. The four pulse period sequences are composed of the repetitions of the corresponding processing periods (ie, pulse periods) among the processing periods P1 to P4.

[0061] The high frequency power source 31 may supply pulse HFP in each of a plurality of processing periods (for example, processing periods P1 to P4). The high frequency power source 31 may repeatedly supply pulse HFP in each of the plurality of pulse period sequences. Figure 6 As shown in FIG. 1 , the high frequency power source 31 repeatedly supplies the pulse HFP in each of the four pulse period sequences which are repeated as the processing periods P1 to P4. Figure 6As shown, in at least a portion of each pulse period, the pulse HFP and the pulse EBP are supplied simultaneously.

[0062] In one embodiment, the high-frequency power supply 31 can use a set of inherent frequencies registered in a corresponding frequency table in one or more waveform cycles CY in each processing period or each pulse period. Afterwards, the high-frequency power supply 31 can adjust the source frequency used in each of the multiple phase periods SP of the waveform cycle CY in each processing period or each pulse period through the first feedback. The first feedback adjusts the source frequency used in each phase period SP in accordance with the degree of reflection of the source high-frequency electric power HF obtained by using different source frequencies in the same phase period in two or more previous waveform cycles in each processing period or each pulse period. The details of the first feedback will be described later.

[0063] In one embodiment, the high-frequency power supply 31 may adjust the source frequency used for the phase period SP in each pulse period by the second feedback. The second feedback adjusts the source frequency used for the phase period SP in each pulse period in accordance with the degree of reflection of the source high-frequency electric power HF obtained by using different source frequencies in the same phase period in the same waveform cycle in two or more previous pulse periods in each pulse period sequence. In addition, the high-frequency power supply 31 may use both the first feedback and the second feedback. The details of the second feedback will be described later.

[0064] In one embodiment, the high frequency power source 31 may be configured to generate a pulse during at least one pulse (eg Figure 6 The OFF period P in the processing period P3) OFF During the OFF period, the source high frequency electric power HF having a power level lower than the power level of the pulse HFP is supplied to the high frequency electrode. OFF The source frequency of the source high-frequency electric power HF is determined in order to suppress the degree of reflection of the source high-frequency electric power HF, and may be a fixed frequency or may vary with time.

[0065] Next, the first feedback and the second feedback are described.

[0066] [1st Feedback]

[0067] The first feedback is performed to adjust the source frequency used for the multiple phase periods SP in each of the multiple waveform cycles CY within each processing period or each pulse period. The multiple waveform cycles CY each include N phase periods SP(1) to SP(N). N is an integer greater than 2. The N phase periods SP(1) to SP(N) divide the multiple waveform cycles CY into N phase periods. In the following description, the waveform cycle CY(m) represents the mth waveform cycle in the continuous multiple waveform cycles CY. The phase period SP(n) represents the nth phase period in the phase periods SP(1) to SP(N). In addition, the phase period SP(m,n) represents the nth phase period in the waveform cycle CY(m).

[0068] The source frequency in the first feedback can be adjusted by the high frequency power supply 31 (or its signal generator 31g). The high frequency power supply 31 adjusts the source frequency of the source high frequency power HF in the phase period SP (m, n) according to the change in the degree of reflection of the source high frequency power HF.

[0069] In order to determine the degree of reflection of the source high-frequency electric power HF, the plasma processing device 1 may further include a sensor 35 and / or a sensor 36. The sensor 35 is capable of measuring the power level Pr of the reflected wave of the source high-frequency electric power HF from the load. The sensor 35 includes, for example, a directional coupler. The directional coupler may be provided between the high-frequency power supply 31 and the matcher 33. In addition, the sensor 35 may be configured to also be capable of measuring the power level Pf of the traveling wave of the source high-frequency electric power HF. The power level Pr of the reflected wave measured by the sensor 35 is notified to the high-frequency power supply 31. In addition, the power level Pf of the traveling wave may also be notified to the high-frequency power supply 31 from the sensor 35.

[0070] The sensor 36 includes a voltage sensor and a current sensor. The sensor 36 can measure a voltage V in a power supply path connecting the high-frequency power source 31 and the high-frequency electrode to each other. HF and current I HF The source high frequency electric power HF is supplied to the high frequency electrode via the power supply path. The sensor 36 may be provided between the high frequency power supply 31 and the matching device 33. The voltage V HF and current I HF The high frequency power supply 31 is notified.

[0071] The high frequency power source 31 generates a representative value from the measured values ​​in each of the multiple phase periods SP. The measured value may be the power level Pr of the reflected wave acquired by the sensor 35. The measured value may also be the value of the ratio of the power level Pr of the reflected wave to the output power level of the source high frequency electric power HF (i.e., reflectivity). The measured value may also be the voltage V obtained by the sensor 36 in each of the multiple phase periods SP. HF With current I HFThe measured value may also be the impedance Z of the load side of the high frequency power supply 31 in each of the multiple phase periods SP. The impedance Z can be obtained from the voltage V obtained by the sensor 36. HF and current I HF The representative value may be an average value or a maximum value of the measured values ​​in each of the plurality of phase periods SP. The high-frequency power source 31 uses the representative value in each of the plurality of phase periods SP as a value indicating the degree of reflection of the source high-frequency electric power HF.

[0072] In the first feedback, the high frequency power supply 31 determines the change in the degree of reflection by using different source frequencies in the corresponding phase periods SP(n) in each of two or more waveform periods CY before the waveform period CY(m) in each processing period or each pulse period.

[0073] By using different source frequencies in the phase period SP(n) in each of two or more waveform periods CY, the relationship between the change in source frequency (frequency shift) and the change in the degree of reflection of the source high-frequency electric power can be determined. Therefore, by using the plasma processing device 1, the source frequency used in the phase period SP(m,n) can be adjusted in accordance with the change in the degree of reflection so as to reduce the degree of reflection. In addition, by using the plasma processing device 1, the degree of reflection can be reduced at a high speed in each of the plurality of waveform periods CY in which the electrical bias EB is provided to the bias electrode of the substrate support portion 11.

[0074] In one embodiment, the two or more waveform periods CY before the waveform period CY(m) include the waveform period CY(m-M1) and the waveform period CY(m-M2). Here, M1 and M2 are natural numbers satisfying M1>M2. In one embodiment, the waveform period CY(m-M1) is the waveform period CY(m-2Q), and the waveform period CY(m-M2) is the waveform period CY(mQ). "Q" and "M2" can be "1", and "2Q" and "M1" can be "2". "Q" can also be an integer greater than 2.

[0075] In the first feedback, the high-frequency power supply 31 imparts a frequency shift in one direction (frequency shift on one side) from the source frequency f(m-M1,n) to the source frequency f(m-M2,n). Here, f(m,n) represents the source frequency of the source high-frequency electric power HF used in the phase period SP(m,n). f(m,n) is represented by f(m,n)=f(m-M2,n)+Δ(m,n). Δ(m,n) represents the amount of frequency shift. The frequency shift in one direction is one of a decrease in frequency and an increase in frequency. If the frequency shift in one direction is a decrease in frequency, Δ(m,n) has a negative value. If the frequency shift in one direction is an increase in frequency, Δ(m,n) has a positive value.

[0076] In the first feedback, when the degree of reflection is reduced by using the source frequency f(m-M2,n) obtained by frequency shifting in one direction, the high-frequency power supply 31 sets the source frequency f(m,n) to a frequency having a frequency shift in one direction relative to the source frequency f(m-M2,n). For example, when the power level Pr(m-M2,n) is reduced from the power level Pr(m-M1,n) by frequency shifting in one direction, the high-frequency power supply 31 sets the source frequency f(m,n) to a frequency having a frequency shift in one direction relative to the source frequency f(m-M2,n). Wherein, Pr(m,n) represents the power level Pr of the reflected wave of the source high-frequency electric power HF in the phase period SP(m,n).

[0077] In the first feedback, a situation may occur where the degree of reflection increases due to the use of the source frequency f(m-M2,n) obtained by frequency shifting in one direction. For example, a situation may occur where the power level Pr(m-M2,n) of the reflected wave increases from the power level Pr(m-M1,n) of the reflected wave due to frequency shifting in one direction. In this case, the high-frequency power supply 31 may set the source frequency f(m,n) to a frequency having a frequency shift in another direction (frequency shift on the other side) relative to the source frequency f(m-M2,n).

[0078] In another embodiment, the source frequency of the source high-frequency electric power HF in the phase period SP(m,n) can be obtained as a frequency that minimizes the degree of reflection based on the degree of reflection (for example, power level Pr) obtained by using different source frequencies in the corresponding phase period SP(n) of each of the two or more waveform periods CY before the waveform period CY(m). The frequency that minimizes the degree of reflection can be obtained by using the least square method of each of the different source frequencies and the corresponding degree of reflection.

[0079] [2nd Feedback]

[0080] Next, the second feedback is described. In the following description, the pulse period P P (k) represents a plurality of pulse periods P in each pulse period sequence P In addition, the waveform period CY(m) represents a plurality of pulse periods P in each pulse period sequence. P The waveform period CY(k, m) represents the mth waveform period in the plurality of waveform periods CY(1) to CY(M). P (k) represents the mth waveform period in the pulse period sequence. PThe nth phase period among the multiple phase periods SP(1) to SP(N) in each of the multiple waveform periods CY. In addition, the phase period SP(m,n) represents the nth phase period in the waveform period CY(m). In addition, the phase period SP(k,m,n) represents the pulse period P in each pulse period sequence. P The nth phase period in the waveform cycle CY(m) within (k).

[0081] In the second feedback, the high frequency power source 31 adjusts the source frequency f(k, m, n) in accordance with the change in the degree of reflection of the source high frequency electric power HF. In the second feedback, the degree of reflection is determined in the same manner as the degree of reflection in the first feedback. In the second feedback, the change in the degree of reflection is determined by changing the pulse period P in each pulse period sequence to the value of the first pulse period. P The source frequencies of the source high frequency electric powers HF are different from each other in the corresponding phase periods SP(n) within the waveform period CY(m). In each pulse period sequence, two or more pulse periods P P Each is relative to the pulse period P P (k) During the preceding pulse.

[0082] In the second feedback, by using more than two pulse periods P P By using different source frequencies in the same phase period within the same waveform cycle in each of the two pulse periods, the relationship between the change in source frequency (frequency shift) and the change in the degree of reflection of the source high-frequency electric power can be determined. Therefore, by using the second feedback, the source frequency used in the phase period SP (k, m, n) can be adjusted in accordance with the change in the degree of reflection to reduce the degree of reflection. In addition, by using the second feedback, it is possible to adjust the source frequency used in the phase period SP (k, m, n) in accordance with the change in the degree of reflection. P In each of the plurality of waveform periods CY, the degree of reflection is reduced at a high speed.

[0083] In each pulse period sequence, relative to the pulse period P P (k) During the first two or more pulses P P , including the (k-K1)th pulse period P P During the (k-K1) and (k-K2)th pulses, P P (k-K2) Here, K1 and K2 are natural numbers satisfying K1>K2.

[0084] In one embodiment, the pulse duration P P (k-K1) is the pulse period P P (k-2). Pulse duration P P (k-K2) is the pulse period P PThe pulse period after (k-K1) is, in one embodiment, the pulse period P P (k-1). That is, in one embodiment, K2 and K1 are 1 and 2 respectively.

[0085] The high-frequency power supply 31 imparts a frequency shift in one direction (frequency shift on one side) from the source frequency in the phase period SP (k-K1, m, n) to the source frequency f (k-K2, m, n) in the phase period SP (k-K2, m, n). Here, f (k, m, n) represents the source frequency of the source high-frequency electric power HF used in the phase period SP (k, m, n). f (k, m, n) is represented by f (k, m, n) = f (k-K2, m, n) + Δ (k, m, n). Δ (k, m, n) represents the amount of frequency shift. The frequency shift in one direction is one of a decrease in frequency and an increase in frequency. If the frequency shift in one direction is a decrease in frequency, Δ (k, m, n) has a negative value. If the frequency shift in one direction is an increase in frequency, Δ (k, m, n) has a positive value.

[0086] In the second feedback, when the degree of reflection is reduced when using the source frequency f(k-K2,m,n) obtained by a frequency shift in one direction, the high-frequency power supply 31 sets the source frequency f(k,m,n) to a frequency having a frequency shift in one direction relative to the source frequency f(k-K2,m,n). For example, when the power level Pr(k-K2,m,n) is reduced from the power level Pr(k-K1,m,n) due to a frequency shift in one direction, the high-frequency power supply 31 sets the source frequency f(k,m,n) to a frequency having a frequency shift in one direction relative to the source frequency f(k-K2,m,n). Pr(k,m,n) represents the power level Pr of the reflected wave of the source high-frequency electric power HF in the phase period SP(k,m,n).

[0087] In the second feedback, a situation may occur where the degree of reflection increases due to the use of the source frequency f(k-K2,m,n) obtained by frequency shifting in one direction. For example, a situation may occur where the power level Pr(k-K2,m,n) of the reflected wave increases from the power level Pr(k-K1,m,n) of the reflected wave due to frequency shifting in one direction. In this case, the high-frequency power supply 31 may set the source frequency f(k,m,n) to a frequency having a frequency shift in another direction (frequency shift on the other side) relative to the source frequency f(k-K2,m,n).

[0088] Alternatively, it may be that, in each pulse period sequence, the source frequency f(k,m,n) is determined by P (k) During the first two or more pulses P PThe degree of reflection (for example, power level Pr) obtained by using two or more different source frequencies of source high-frequency electric power HF in the corresponding phase period SP(n) within the waveform period CY(m) is obtained as the frequency that minimizes the degree of reflection. The frequency that minimizes the degree of reflection can be obtained by using the least square method of each of the different source frequencies and the corresponding degree of reflection.

[0089] Below, refer to Figure 7 (a) Figure 7 (b) and Figure 7 (c). Figure 7 (a) Figure 7 (b) and Figure 7 (c) are diagrams each showing a pulse period in a pulse period sequence related to a plasma processing apparatus according to an exemplary embodiment.

[0090] The multiple pulse periods P in each pulse period sequence P Can include 1st to Kth a Pulse duration P P (1)~P P (K a ). Here, K a is a natural number greater than 2. It can be that the high frequency power supply 31 has a pulse period P P (1)~P P (K a ) each includes the first to the Mth of the plurality of waveform cycles CY a Waveform cycles CY(1)~CY(M a ) respectively, the frequency set registered in the above-mentioned corresponding frequency table is used. The high frequency power source 31 is in the pulse period P P (1)~P P (K a ) each of the 1st to the Mth a Waveform cycles CY(1)~CY(M a ) In each of the multiple phase periods SP, multiple frequencies included in the frequency set registered in the corresponding frequency table are used as source frequencies.

[0091] The high frequency power source 31 may be configured such that the pulse period P in each pulse period sequence is P (1)~P P (K a ) respectively, in the waveform period CY (M a ) and then the first feedback is performed. That is, the high frequency power supply 31 may be configured such that during the pulse period P in each pulse period sequence P (1)~P P (Ka ) each includes a waveform period CY(M a +1)~CY(M) performs the above-mentioned first feedback.

[0092] In one embodiment, the plurality of pulse periods P in each pulse period sequence may be P Also includes the (K a +1) to Kth b Pulse duration P P (K a +1)~P P (K). Here, K represents the last pulse period P in each pulse period sequence. P The natural numbers in order.

[0093] The high frequency power source 31 can be configured to generate a pulse during the pulse period P in each pulse period sequence. P (K a +1)~P P (K) The 1st to Mth items included in each b Waveform cycles CY(1)~CY(M b ) to perform the second feedback described above. Here, M b is a natural number. In addition, the high frequency power supply 31 can be in each pulse period P in the pulse period sequence P (K a +1)~P P (K) In each case, in the waveform period CY(M b ) and then perform the first feedback. That is, the high frequency power supply 31 can be used during the pulse period P in each pulse period sequence. P (K a +1)~P P (K) The waveform period CY(M) included in each b The above-mentioned first feedback is performed in the steps of:

[0094] Below, refer to Figure 8 . Figure 8 is a flow chart of a plasma processing method according to an exemplary embodiment. Figure 8 The illustrated plasma processing method (hereinafter referred to as “method MT”) can be performed using the plasma processing apparatus 1 .

[0095] like Figure 8 As shown, the method MT starts at step STp. In step STp, a substrate W is prepared on the substrate support 11 in the chamber 10.

[0096] In method MT, as described above, regarding the plasma processing apparatus 1 , as the processing conditions for plasma processing on the substrate W, a plurality of processing conditions that are different from each other are used in a plurality of processing periods.

[0097] In one embodiment, step STa is performed during the first processing period. In step STa, the first plasma treatment is performed under the first processing condition. The first processing condition includes supplying a first processing gas from which plasma can be generated into the chamber 10. Step STa may be performed only once. Alternatively, step STa may be performed repeatedly. That is, pulse EBP may be repeatedly supplied in a first pulse period sequence consisting of repeated performance of the first processing period. In the case of repeatedly performing step STa, in step STJA, it is determined whether a stop condition is satisfied. In step STJA, the stop condition is satisfied when the number of repetitions of step STa reaches a predetermined number of times. When it is determined in step STJA that the stop condition is not satisfied, step STa is performed again. When it is determined in step STJA that the stop condition is satisfied, the repetition of step STa ends.

[0098] In one embodiment, step STb is performed during the second processing period. In step STb, the second plasma treatment is performed under the second processing condition. The second processing condition includes: supplying a second processing gas from which plasma can be generated into the chamber 10. The second processing gas is a processing gas different from the first processing gas. Step STb may be performed only once. Alternatively, step STb may be performed repeatedly. That is, in a second pulse period sequence consisting of repeated performance of the second processing period, pulse EBP may be repeatedly supplied. In the case of repeatedly performing step STb, it is determined in step STJB whether the stop condition is satisfied. In step STJB, the stop condition is satisfied when the number of repetitions of step STb reaches a specified number of times. When it is determined in step STJB that the stop condition is not satisfied, step STb is performed again. When it is determined in step STJB that the stop condition is satisfied, the repetition of step STb ends.

[0099] In method MT, a loop including step STa and step STb can be repeatedly performed. In this case, in step STJZ, it is determined whether the end condition is satisfied. In step STJZ, the end condition is satisfied when the number of repetitions of the loop reaches a predetermined number. When it is determined in step STJZ that the end condition is not satisfied, the loop is performed again. When it is determined in step STJZ that the stop condition is satisfied, the repetition of the loop ends.

[0100] Furthermore, the method MT may include three or more steps of performing plasma treatment on the substrate W. The three or more steps include a step STa and a step STb. The three or more steps are respectively performed in three or more treatment periods. In the three or more treatment periods, as described above, three or more treatment conditions different from each other are respectively used as treatment conditions for performing plasma treatment on the substrate W. Furthermore, a cycle of the method MT may include these three or more steps.

[0101] In method MT, during the first processing period, a plurality of frequencies included in a first frequency set are used as source frequencies for each of the plurality of phase periods SP within a waveform period CY of the electric bias EB. The first frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power HF from the load during the first processing period. Furthermore, during the second processing period, a plurality of frequencies included in a second frequency set different from the first frequency set are used as source frequencies for each of the plurality of phase periods SP within a waveform period CY of the electric bias EB. The second frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power HF from the load during the second processing period. Thus, in method MT, a plurality of frequency sets different from each other are used in the above-mentioned plurality of processing periods.

[0102] Various exemplary embodiments have been described above, but the present invention is not limited to the exemplary embodiments described above, and various additions, omissions, substitutions, and changes may be made. In addition, elements in different embodiments may be combined to form other embodiments.

[0103] In other embodiments, the plasma processing device may be an inductively coupled plasma processing device, an ECR plasma processing device, a helicon wave excitation plasma processing device, or a surface wave plasma processing device. In any of the plasma processing devices, the source high frequency electric power HF is used to generate plasma, and the source frequency of the source high frequency electric power HF can be adjusted as described above with respect to the plasma processing device 1.

[0104] Here, various exemplary embodiments included in the present invention are described in the following [E1] to [E9].

[0105] [E1]

[0106] A plasma processing device, characterized in that it comprises:

[0107] Chamber;

[0108] a substrate support portion disposed within the chamber;

[0109] a gas supply unit capable of supplying gas into the chamber;

[0110] a high frequency power supply capable of supplying a source high frequency electric power to generate a plasma from a gas in the chamber; and

[0111] a bias power supply electrically coupled to the substrate support and capable of generating an electrical bias,

[0112] The high frequency power supply is composed of:

[0113] It is possible to use a plurality of frequencies included in a first frequency set as source frequencies of the source high-frequency electric power for each of a plurality of phases in a waveform period of the electrical bias during a first process in which a first process condition is applied, wherein the first process condition includes supplying a first process gas from the gas supply unit into the chamber, the first frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from a load, and,

[0114] It is possible to use, during a second process in which a second process condition is applied, a plurality of frequencies included in a second frequency set different from the first frequency set as the source frequencies used for each of the plurality of phase periods within the waveform period of the electrical bias, wherein the second process condition includes supplying a second process gas from the gas supply unit into the chamber, and the second frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from a load.

[0115] In the embodiment [E1], the frequency set determined to suppress the degree of reflection of the source high frequency electric power from the load during the multiple phases in the waveform cycle of the electric bias can be selected at least in accordance with the process gas. Therefore, the degree of reflection of the source high frequency electric power can be reduced during the multiple phases in the waveform cycle of the electric bias in each of two or more periods using different process gases.

[0116] [E2]

[0117] The plasma processing device as described in [E1] is characterized in that:

[0118] The electrical bias is a voltage pulse sequence comprising voltage pulses periodically generated at time intervals equal to the time length of the waveform period,

[0119] The first processing condition and the second processing condition each also include: the power level of the source high-frequency electric power, the level of the electrical bias, the duty cycle of the voltage pulse of the electrical bias in the waveform period, the bias frequency which is the inverse of the waveform period, and at least one of the pressure in the chamber.

[0120] [E3]

[0121] The plasma processing device as described in [E1] is characterized in that:

[0122] The electric bias is a bias high frequency electric power having the waveform period,

[0123] The first processing condition and the second processing condition each further include: at least one of the power level of the source high-frequency electric power, the level of the electrical bias, the bias frequency which is the inverse of the waveform period, and the pressure within the chamber.

[0124] [E4]

[0125] The plasma processing device as described in any one of [E1] to [E3], characterized in that:

[0126] The plurality of frequencies of the first frequency set are registered in a first frequency table prepared in advance in a storage unit of the plasma processing apparatus.

[0127] The plurality of frequencies of the second frequency set are registered in a second frequency table prepared in advance in the storage unit.

[0128] [E5]

[0129] The plasma processing device as described in any one of [E1] to [E4], characterized in that:

[0130] The high-frequency power supply is configured to be able to adjust the source frequency used in the nth phase period within the mth waveform period of the electrical bias in accordance with the change in the degree of reflection of the source high-frequency electric power during each of the first processing period and the second processing period, wherein the change in the degree of reflection of the source high-frequency electric power is a change in the degree of reflection of the source high-frequency electric power when the source frequency of different frequencies is used in the nth phase period within two or more waveform periods of the electrical bias prior to the mth waveform period.

[0131] [E6]

[0132] The plasma processing device as described in any one of [E1] to [E5], characterized in that:

[0133] The bias power supply is composed of:

[0134] The pulse of the electrical bias can be supplied in each of a plurality of pulse periods as a repetition of the first processing period included in the first pulse period sequence, and

[0135] The pulse of the electrical bias can be supplied in each of a plurality of pulse periods as a repetition of the second processing period included in the second pulse period sequence.

[0136] [E7]

[0137] The plasma processing device as described in [E6] is characterized in that:

[0138] The high-frequency power supply is configured to be able to adjust the source frequency used in the nth phase period within the mth waveform cycle within the kth pulse period in accordance with the change in the degree of reflection of the source high-frequency electric power in each of the first pulse period sequence and the second pulse period sequence, wherein the change in the degree of reflection of the source high-frequency electric power is the change in the degree of reflection of the source high-frequency electric power when a source frequency of a different frequency is used in the nth phase period within the mth waveform cycle within two or more pulse periods prior to the kth pulse period.

[0139] [E8]

[0140] The plasma processing device as described in [E6] or [E7] is characterized in that:

[0141] The high frequency power supply is composed of:

[0142] A pulse of the source high-frequency electric power can be supplied in each of the plurality of pulse periods included in the first pulse period sequence, and

[0143] A pulse of the source high-frequency electric power can be supplied in each of the plurality of pulse periods included in the second pulse period sequence.

[0144] [E9]

[0145] A plasma treatment method, comprising:

[0146] The step of preparing a substrate on a substrate support in a chamber of a plasma processing apparatus;

[0147] A step of performing a first plasma treatment on the substrate using a first treatment condition during a first treatment period, wherein the first treatment condition includes supplying a first treatment gas into the chamber from a gas supply unit; and

[0148] A step of performing a second plasma treatment on the substrate using a first processing condition during a second processing period, wherein the first processing condition includes supplying a second processing gas from a gas supply unit into the chamber,

[0149] In each of the first processing period and the second processing period, source high frequency electric power for generating plasma is supplied, and an electric bias is supplied from a bias power supply to the substrate support portion,

[0150] During the first processing period, a plurality of frequencies included in a first frequency set are used as source frequencies of the source high-frequency electric power for each of a plurality of phases within a waveform period of the electrical bias, wherein the first frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from the load,

[0151] During the second processing, multiple frequencies included in a second frequency set different from the first frequency set are used as the source frequencies for each of the multiple phase periods within the waveform period of the electrical bias, wherein the second frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from the load.

[0152] It should be understood from the above description that the various embodiments of the present invention are described in this specification for the purpose of illustration, and various changes can be made without departing from the scope and spirit of the present invention. Therefore, the various embodiments disclosed in this specification are not intended to be limited, and the true scope and spirit are represented by the attached claims.

[0153] Description of Reference Numerals

[0154] 1 ... plasma processing apparatus, 10 ... chamber, 11 ... substrate support portion, 31 ... high frequency power supply, 32 ... bias power supply.

Claims

1. A plasma processing device, characterized in that: include: Chamber; a substrate support portion disposed within the chamber; a gas supply unit capable of supplying gas into the chamber; a high frequency power supply capable of supplying a source high frequency electric power to generate a plasma from a gas in the chamber; and a bias power supply electrically coupled to the substrate support and capable of generating an electrical bias, The high frequency power supply is composed of: It is possible to use a plurality of frequencies included in a first frequency set as source frequencies of the source high-frequency electric power for each of a plurality of phases in a waveform period of the electrical bias during a first process in which a first process condition is applied, wherein the first process condition includes supplying a first process gas from the gas supply unit into the chamber, the first frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from a load, and, It is possible to use, during a second process in which a second process condition is applied, a plurality of frequencies included in a second frequency set different from the first frequency set as the source frequencies used for each of the plurality of phase periods within the waveform period of the electrical bias, wherein the second process condition includes supplying a second process gas from the gas supply unit into the chamber, and the second frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from a load.

2. The plasma processing device according to claim 1, wherein: The electrical bias is a voltage pulse sequence comprising voltage pulses periodically generated at time intervals equal to the time length of the waveform period, The first processing condition and the second processing condition each also include: the power level of the source high-frequency electric power, the level of the electrical bias, the duty cycle of the voltage pulse of the electrical bias in the waveform period, the bias frequency which is the inverse of the waveform period, and at least one of the pressure in the chamber.

3. The plasma processing apparatus according to claim 1, wherein: The electric bias is a bias high frequency electric power having the waveform period, The first processing condition and the second processing condition each further include: at least one of the power level of the source high-frequency electric power, the level of the electrical bias, the bias frequency which is the inverse of the waveform period, and the pressure within the chamber.

4. The plasma processing apparatus according to claim 1, wherein: The plurality of frequencies of the first frequency set are registered in a first frequency table prepared in advance in a storage unit of the plasma processing apparatus. The plurality of frequencies of the second frequency set are registered in a second frequency table prepared in advance in the storage unit.

5. The plasma processing device according to any one of claims 1 to 4, characterized in that: The high-frequency power supply is configured to be able to adjust the source frequency used in the nth phase period within the mth waveform period of the electrical bias in accordance with the change in the degree of reflection of the source high-frequency electric power during each of the first processing period and the second processing period, wherein the change in the degree of reflection of the source high-frequency electric power is a change in the degree of reflection of the source high-frequency electric power when the source frequency of different frequencies is used in the nth phase period within two or more waveform periods of the electrical bias prior to the mth waveform period.

6. The plasma processing apparatus according to any one of claims 1 to 4, characterized in that: The bias power supply is composed of: The pulse of the electrical bias can be supplied in each of a plurality of pulse periods as a repetition of the first processing period included in the first pulse period sequence, and The pulse of the electrical bias can be supplied in each of a plurality of pulse periods as a repetition of the second processing period included in the second pulse period sequence.

7. The plasma processing apparatus according to claim 6, wherein: The high-frequency power supply is configured to be able to adjust the source frequency used in the nth phase period within the mth waveform cycle within the kth pulse period in accordance with the change in the degree of reflection of the source high-frequency electric power in each of the first pulse period sequence and the second pulse period sequence, wherein the change in the degree of reflection of the source high-frequency electric power is the change in the degree of reflection of the source high-frequency electric power when a source frequency of a different frequency is used in the nth phase period within the mth waveform cycle within two or more pulse periods prior to the kth pulse period.

8. The plasma processing apparatus according to claim 6, wherein: The high frequency power supply is composed of: A pulse of the source high-frequency electric power can be supplied in each of the plurality of pulse periods included in the first pulse period sequence, and A pulse of the source high-frequency electric power can be supplied in each of the plurality of pulse periods included in the second pulse period sequence.

9. A plasma treatment method, characterized in that: include: The step of preparing a substrate on a substrate support in a chamber of a plasma processing apparatus; A step of performing a first plasma treatment on the substrate using a first treatment condition during a first treatment period, wherein the first treatment condition includes supplying a first treatment gas into the chamber from a gas supply unit; and A step of performing a second plasma treatment on the substrate using a first processing condition during a second processing period, wherein the first processing condition includes supplying a second processing gas from a gas supply unit into the chamber, In each of the first processing period and the second processing period, source high frequency electric power for generating plasma is supplied, and an electric bias is supplied from a bias power supply to the substrate support portion, During the first processing period, a plurality of frequencies included in a first frequency set are used as source frequencies of the source high-frequency electric power for each of a plurality of phases within a waveform period of the electrical bias, wherein the first frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from the load, During the second processing, multiple frequencies included in a second frequency set different from the first frequency set are used as the source frequencies for each of the multiple phase periods within the waveform period of the electrical bias, wherein the second frequency set is determined in order to suppress the degree of reflection of the source high-frequency electric power from the load.

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