Etching method and plasma processing system

Abstract

The purpose of the present invention is to provide a technology with which it is possible to reduce the environmental load in etching.　A processing gas which contains at least one first gas that is selected from the group consisting of an F2 gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and a second gas represented by CmHn (wherein, m is an integer of 0 or more, and n is an integer of 2 or more) is used as a processing gas that is supplied when a film to be etched containing at least one selected from the group consisting of silicon and a metal is plasma-etched.

Description

Etching method and plasma processing system

[0001] Exemplary embodiments of this disclosure relate to etching methods and plasma processing systems.

[0002] Patent Document 1 discloses a technology related to the ALE (Atomic Layer Etching) method.

[0003] Japanese Patent Publication No. 2018-183319

[0004] This disclosure provides a technology that can reduce the environmental impact of etching.

[0005] In one exemplary embodiment of the present disclosure, (a) a step of preparing a substrate on a substrate support in a chamber including a substrate support, wherein the substrate comprises an etching target film comprising at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, the mask having at least one opening that exposes the etching target film, and (b) a step of supplying a processing gas into the chamber, wherein the processing gas is F ２ A first gas selected from the group consisting of gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and C ｍ H ｎ An etching method is provided, comprising: (c) a step of etching the film to be etched through the opening with plasma generated from the processing gas, comprising: (a) a step of including a second gas represented by (c) an integer of 0 or more (where m represents an integer of 2 or more).

[0006] According to one exemplary embodiment of the present disclosure, a technology can be provided that can reduce the environmental impact of etching.

[0007] This is a diagram for explaining a configuration example of a plasma processing system. This is a diagram for explaining a configuration example of an inductively coupled plasma processing apparatus. This is a flowchart showing an example of this etching method. This is a diagram showing an example of a cross-sectional structure of a substrate W prepared in step ST1. This is a diagram showing an example of a cross-sectional structure of the substrate W after performing steps ST2 and ST3. This is a diagram showing a modified example of an inductively coupled plasma processing apparatus.

[0008] Hereinafter, each embodiment of the present disclosure will be described.

[0009] In one exemplary embodiment, (a) in a chamber including a substrate support portion, a step of preparing a substrate on the substrate support portion, wherein the substrate includes an etching target film containing at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, the mask having at least one opening exposing the etching target film; (b) a step of supplying a processing gas into the chamber, the processing gas including at least one first gas selected from the group consisting of F ２ gas, a fluorine-containing gas having a C—O bond, a fluorine-containing gas having a C═O bond, a fluorine-containing gas having a C═C bond, a fluorine-containing gas having an N—O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and a second gas represented by C ｍ H ｎ (where m represents an integer of 0 or more and n represents an integer of 2 or more); and (c) a step of etching the etching target film through the opening with plasma generated from the processing gas. An etching method is provided.

[0010] In one exemplary embodiment, the first gas is F ２ , CF ３ OF, COF ２ , l-C ４ F ８ , CHF ２ COF, CF ３ COF, C ３ F ６ , C ４ F ６ , F ３ NO, and IF７ It includes at least one selected from the group consisting of the following.

[0011] In one exemplary embodiment, the second gas is H ２ and CH ４ It includes at least one selected from the group consisting of the following.

[0012] In one exemplary embodiment, the first gas is COF ２ The above second gas includes H ２ Includes.

[0013] In one exemplary embodiment, the processing gas is C ｘ H ｙ F ｚ It further includes a third gas represented by (where x represents an integer greater than or equal to 2, y represents an integer greater than or equal to 1, and z represents an integer greater than or equal to 1).

[0014] In one exemplary embodiment, the third gas is C ２ H ２ F ２ , C ２ HF ３ , C ２ H ５ F, C ３ H ２ F ４ and C ４ H ２ F ６ It includes at least one selected from the group consisting of the following.

[0015] In one exemplary embodiment, the processing gas is HF gas, phosphorus-containing gas, nitrogen gas, NH ３ Gas, H ２ The mixture further includes at least one fourth gas selected from the group consisting of O gas, halogen-containing gases, and metal-containing gases.

[0016] In one exemplary embodiment, the flow rate of the first gas is greater than the flow rate of the HF gas.

[0017] In one exemplary embodiment, the flow rate of the HF gas is 500 sccm or less.

[0018] In one exemplary embodiment, the phosphorus-containing gas is PF３ , PF ５ , POCl ３ and PCL ３ The halogen-containing gas comprises at least one selected from the group consisting of HBr, HCl, and BCl. ３ The metal-containing gas comprises at least one selected from the group consisting of SnCl ４ WF ６ WCl ６ and MoF ６ It includes at least one selected from the group consisting of the following.

[0019] In one exemplary embodiment, in (c) above, the plasma is generated by supplying a source RF signal to the plasma generation unit.

[0020] In one exemplary embodiment, the film to be etched is a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a low dielectric constant film, Al ２ O ３ membrane, ZrO ２ membrane, HfO ２ It includes at least one selected from the group consisting of a membrane, an IGZO membrane, a Pt-containing membrane, and a Ru-containing membrane.

[0021] In one exemplary embodiment, the apparatus comprises a chamber, a substrate support provided within the chamber, an electrostatic chuck provided on the substrate support, a gas supply unit configured to supply a processing gas into the chamber, a plasma generation unit configured to generate plasma from the processing gas, and a control unit, wherein the control unit includes: (a) control for holding a substrate on the substrate support by the electrostatic chuck, wherein the substrate comprises an etching target film including at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, wherein the mask has at least one opening that exposes the etching target film; and (b) control for supplying the processing gas into the chamber by the gas supply unit, wherein the processing gas is F ２A first gas selected from the group consisting of gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and C ｍ H ｎ A plasma processing apparatus is provided, configured to perform control including (c) a control that includes a second gas represented by (m) an integer greater than or equal to 0, and n an integer greater than or equal to 2, and (c) a control that etches the film to be etched with the plasma generated from the processing gas by the plasma generation unit.

[0022] In one exemplary embodiment, the processing gas further includes HF gas, and the gas supply unit includes a first supply channel configured to supply a gas other than the HF gas from the processing gas, and a second supply channel configured to supply the HF gas.

[0023] In one exemplary embodiment, the second supply channel is connected to a gas source containing HF in liquid form.

[0024] In one exemplary embodiment, the second supply channel includes a vaporizer and a heater.

[0025] In one exemplary embodiment, the constituent material of the second supply channel has higher corrosion resistance than the constituent material of the first supply channel.

[0026] In one exemplary embodiment, the first gas is COF ２ The above second gas includes H ２ Includes.

[0027] In one exemplary embodiment, in (c) above, the control unit is configured to perform control to supply a source RF signal to the substrate support unit.

[0028] In one exemplary embodiment, in (b) above, the flow rate of the first gas is greater than the flow rate of the HF gas.

[0029] Hereinafter, each embodiment of this disclosure will be described in detail with reference to the drawings. In each drawing, the same or similar elements are denoted by the same reference numeral, and redundant explanations are omitted. Unless otherwise specified, positional relationships such as top, bottom, left, and right will be described based on the positional relationships shown in the drawings. The dimensional ratios in the drawings do not represent actual ratios, and actual ratios are not limited to those shown.

[0030] <Example of a Plasma Processing System> Figure 1 is a diagram illustrating an example of the 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 unit 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 outlet for discharging gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20, which will be described later, and the gas outlet is connected to an exhaust system 40, which will be described later. The substrate support unit 11 is located in the plasma processing space and has a substrate support surface for supporting a substrate.

[0031] The plasma generation 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), ECR (Electron Cyclotron Resonance) plasma, helicon wave excited plasma (HWP), or surface wave plasma (SWP), etc. Various types of plasma generation units, including AC (Alternating Current) plasma generation units and DC (Direct Current) plasma generation units, may also be used. In one embodiment, the AC signal (AC power) used in the AC plasma generation unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes an RF (Radio Frequency) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 100 kHz to 150 MHz.

[0032] The control unit 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described herein. The control unit 2 may be configured to control the elements of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the control unit 2 may be included in the plasma processing apparatus 1. The control unit 2 is implemented, for example, by a computer 2a. The control unit 2 may include a processing unit 2a1, a storage unit 2a2, and a communication interface 2a3. The functions realized by the processing unit 2a1 described herein may be implemented in a circuit or processing circuit, including a general-purpose processor, an application-specific processor, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (Central Processing Unit), a conventional circuit, and / or a combination thereof, programmed to realize the described functions. The processor is considered to be a circuit or processing circuit, including transistors and other circuits. The processor may be a programmed processor that executes a program stored in the storage unit 2a2. This program may be pre-stored in the storage unit 2a2 or retrieved via a medium when needed. The acquired program is stored in the storage unit 2a2 and read from the storage unit 2a2 and executed by the processing unit 2a1. The medium may be various storage media readable by the computer 2a, or it may be a communication line connected to the communication interface 2a3. The storage unit 2a2 may include RAM (Random Access Memory), ROM (Read Only Memory), HDD (Hard Disk Drive), 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).In this disclosure, circuits, units, and means are hardware programmed to perform or configured to perform the functions described. Such hardware may be any hardware described in this disclosure, or any hardware known to be programmed to perform or execute the functions described. If such hardware is a processor that is considered to be a type of circuit, such circuit, means, or unit is a combination of hardware and software used to constitute such hardware and / or processor.

[0033] The following describes an example configuration of an inductively coupled plasma processing apparatus as an example of a plasma processing apparatus 1. Figure 2 is a diagram illustrating an example configuration of an inductively coupled plasma processing apparatus.

[0034] The inductively 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. The plasma processing chamber 10 includes a dielectric window 101. The plasma processing apparatus 1 also includes a substrate support unit 11, a gas introduction unit, and an antenna 14. The substrate support unit 11 is located inside the plasma processing chamber 10. The antenna 14 is located on or above the plasma processing chamber 10 (i.e., on or above the dielectric window 101). The plasma processing chamber 10 has a plasma processing space 10s defined by the dielectric window 101, the side walls 102 of the plasma processing chamber 10, and the substrate support unit 11. The plasma processing chamber 10 is grounded.

[0035] The substrate support portion 11 includes a main body portion 111 and a ring assembly 112. The main body portion 111 has a central region 111a for supporting the substrate W and 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 portion 111 surrounds the central region 111a of the main body portion 111 in a plan view. The substrate W is placed on the central region 111a of the main body portion 111, and the ring assembly 112 is placed on the annular region 111b of the main body portion 111 so as to surround the substrate W on the central region 111a of the main body portion 111. Therefore, the central region 111a is also called the substrate support surface for supporting the substrate W, and the annular region 111b is also called the ring support surface for supporting the ring assembly 112.

[0036] In one embodiment, the main body 111 includes a base 1110 and an electrostatic chuck 1111. The base 1110 includes a conductive member. The conductive member of the base 1110 can function as a bias electrode. The electrostatic chuck 1111 is placed on the base 1110. The electrostatic chuck 1111 includes a ceramic member 1111a and an electrostatic chuck electrode 1111b placed within the ceramic member 1111a. The electrostatic chuck electrode 1111b is also called a clamping electrode. In one embodiment, the electrostatic chuck electrode 1111b is electrically connected or coupled to a chuck power supply. The chuck power supply may be a DC power supply or an AC power supply. The ceramic member 1111a has a central region 111a. In one embodiment, the ceramic member 1111a also has an annular region 111b. Furthermore, other members surrounding the electrostatic chuck 1111, such as an annular electrostatic chuck or an annular insulating member, may have an annular region 111b. In this case, the ring assembly 112 may be placed on the annular electrostatic chuck or the annular insulating member, or on both the electrostatic chuck 1111 and the annular insulating member. Also, at least one bias electrode, electrically connected or coupled to the power supply 31 and / or power supply 32 described later, may be placed inside the ceramic member 1111a. Furthermore, the conductive member of the base 1110 and the bias electrode inside the ceramic member 1111a may function as multiple bias electrodes. Also, the electrostatic chuck electrode 1111b may function as a bias electrode. Therefore, the substrate support portion 11 includes at least one bias electrode.

[0037] 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 covering ring. The edge rings are formed of a conductive or insulating material, and the covering rings are formed of an insulating material.

[0038] The substrate support section 11 may also include a temperature control 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 control module may include a heater, a heat transfer medium, a flow path 1110a, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path 1110a. In one embodiment, the flow path 1110a is formed within the base 1110, and one or more heaters are arranged within the ceramic member 1111a of the electrostatic chuck 1111. The substrate support section 11 may also include a heat transfer gas supply section configured to supply heat transfer gas to the gap between the back surface of the substrate W and the central region 111a.

[0039] The gas introduction section is configured to introduce at least one processing gas from the gas supply section 20 into the plasma processing space 10s. In one embodiment, the gas introduction section includes a central gas injector (CGI) 13. The central gas injector 13 is located above the substrate support section 11 and is attached to a central opening formed in the dielectric window 101. The central gas injector 13 has at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas inlet 13c. The processing gas supplied to the gas supply port 13a passes through the gas flow path 13b and is introduced into the plasma processing space 10s from the gas inlet 13c. In addition to or instead of the central gas injector 13, the gas introduction section may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the side wall 102.

[0040] 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 processing gas to the gas inlet from a corresponding gas source 21 via a corresponding flow controller 22. 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 that modulates or pulses the flow rate of at least one processing gas.

[0041] The power supply system 30 includes a power supply 31 that is electrically connected to or coupled to the plasma processing chamber 10. In one embodiment, the power supply 31 is electrically connected to or coupled to the plasma processing chamber 10 via at least one impedance matcher. The impedance matcher may be a mechanically controlled matcher or an electronically controlled matcher. The power supply 31 is configured to supply at least one RF signal (RF power) to at least one bias electrode and antenna 14. This generates plasma from at least one processing gas supplied to the plasma processing space 10s. Therefore, the power supply 31 can function as at least part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to at least one bias electrode, a bias potential is generated on the substrate W, and ions in the formed plasma can be drawn into the substrate W.

[0042] The power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is electrically connected to or coupled to the antenna 14 and is configured to generate a source RF signal (source RF power) to generate plasma in the plasma processing space 10s. In one embodiment, the first RF generation unit 31a is electrically connected to or coupled to the antenna 14 via at least one impedance matcher. In one embodiment, the source RF signal has a frequency in the range of 10 MHz to 150 MHz. In one embodiment, the first RF generation unit 31a may be configured to generate a plurality of source RF signals having different frequencies. One or more generated source RF signals are supplied to the antenna 14.

[0043] The second RF generation unit 31b is electrically connected to or coupled to at least one bias electrode and is configured to generate a bias RF signal (bias RF power). In one embodiment, the second RF generation unit 31b is electrically connected to or coupled to at least one bias electrode via at least one impedance matcher. The frequency of the bias RF signal may be the same as or different from the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency lower than the frequency of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 100 kHz to 60 MHz. In one embodiment, the second RF generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated one or more bias RF signals are supplied to at least one bias electrode. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0044] The power supply system 30 may also include a power supply 32 that is electrically connected to or coupled to the plasma processing chamber 10. The power supply 32 includes a voltage generation unit 32a. In one embodiment, the voltage generation unit 32a is electrically connected to or coupled to at least one bias electrode and is configured to generate a voltage signal. The generated voltage signal is applied to at least one bias electrode.

[0045] In various embodiments, the voltage signal may be pulsed. In this case, the voltage generation unit 32a functions as a voltage pulse generation unit configured to generate a sequence of voltage pulses. Thus, the sequence of voltage pulses is applied to at least one bias electrode. In one embodiment, the sequence of voltage pulses has multiple cycles, each cycle including a burst of voltage pulses in a first period and a constant reference voltage in a second period. That is, the burst of voltage pulses is repeated in the sequence of voltage pulses. The absolute value of the voltage level of the voltage pulse is greater than the absolute value of the voltage level of the reference voltage. The voltage pulse may have an arbitrary waveform having a rectangular, trapezoidal, triangular, or a combination thereof, and the arbitrary waveform may change over time. The voltage pulse may have positive or negative polarity. Furthermore, the sequence of voltage pulses may include one or more positive voltage pulses and one or more negative voltage pulses within one cycle. Note that the voltage generation unit 32a may be provided in addition to the power supply 31, or it may be provided in place of the second RF generation unit 31b.

[0046] The antenna 14 includes one or more coils. In one embodiment, the antenna 14 may include an outer coil and an inner coil arranged coaxially. In this case, the power supply 31 may be connected to both the outer coil and the inner coil, or to either the outer coil or the inner coil. In the former case, the same RF generation unit may be connected to both the outer coil and the inner coil, or separate RF generation units may be connected to the outer coil and the inner coil separately.

[0047] The exhaust system 40 may be connected to, for example, a gas outlet 10e located 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 regulating valve regulates the pressure in the plasma processing space 10s. The vacuum pump may include a turbomolecular pump, a dry pump, or a combination thereof.

[0048] <Example of Etching Method> Figure 3 is a flowchart of an etching method according to an exemplary embodiment (hereinafter also referred to as "this etching method"). This etching method includes a step ST1 for preparing a substrate, a step ST2 for supplying a processing gas, and a step ST3 for performing etching. Each step may be performed using any one of the plasma processing systems described above (see Figures 1 to 2), or using two or more of these plasma processing systems. For example, this etching method may be performed using the plasma processing apparatus shown in Figure 2. In the following, the case in which the control unit 2 controls each part of the plasma processing apparatus 1 to perform this etching method on the substrate W will be described as an example.

[0049] (Step ST1: Preparation of Substrate) In Step ST1, the substrate W is prepared on the substrate support portion 11 in the plasma processing chamber 10 (hereinafter also referred to as "chamber 10"). The substrate W comprises an etching target film EF and a mask MK placed on the etching target film EF. The mask MK comprises at least one opening OP that exposes the etching target film EF. The substrate W may be used in the manufacture of semiconductor devices. Semiconductor devices include, for example, memory devices such as DRAM and 3D-NAND flash memory, and logic devices.

[0050] Figure 4 shows an example of the cross-sectional structure of the substrate W prepared in step ST1. As illustrated in Figure 4, the substrate W may be constructed by stacking the etching target film EF and the mask MK on an arbitrary underlay film UF in that order.

[0051] The underlayer film UF is, in one example, a silicon wafer or an organic film, dielectric film, metal film, or semiconductor film formed on a silicon wafer. For example, a dielectric film may contain SiN, etc. For example, a metal film may contain TiN, TaN, W, WSi, and WC, etc. The underlayer film UF may be composed of multiple films stacked on top of each other.

[0052] The etchable film EF may include, for example, at least one selected from the group consisting of silicon and metal. The etchable film may be, for example, a silicon-containing film or a metal-containing film. Examples of silicon-containing films include silicon oxide films, silicon nitride films, silicon oxynitride films, and low dielectric constant films. Low dielectric constant films may contain silicon and be used as interlayer insulating films, and examples include films containing SiOC, SiOF, SiCOH, etc. Examples of metal-containing films include Al ２ O ３ membrane, ZrO ２ membrane, HfO ２ Examples include films, Pt-containing films, Ru-containing films, IGZO (indium gallium zinc oxide) films, etc. Examples of Pt-containing films include Pt films and Pt oxide films. Examples of Ru-containing films include Ru films and Ru oxide films. In one embodiment, the film EF to be etched is a silicon oxide film, a silicon nitride film, a silicon oxynitride film, a low dielectric constant film, Al ２ O ３ membrane, ZrO ２ membrane, HfO ２ The substrate W contains at least one selected from the group consisting of films, IGZO films, Pt-containing films, and Ru-containing films. The etchable film EF and the arbitrary undercoat film UF constituting the substrate W may be formed by CVD, atomic layer deposition (ALD), spin coating, etc. The etchable film EF and the arbitrary undercoat film UF may be flat films or films with irregularities.

[0053] The mask MK is formed on the film EF to be etched and has at least one opening OP. The mask MK may contain at least one selected from silicon-containing films, carbon-containing films, and metal-containing films. For example, the silicon-containing film may be a silicon oxide film, a silicon nitride film, a silicon carbonitride film, a polycrystalline silicon film, or a carbon-containing silicon film. For example, the silicon oxide film may be TEOS (tetraethoxysilane). The silicon-containing film may be doped with elements such as phosphorus, boron, or nitrogen. If the film EF to be etched is a silicon-containing film, the mask MK is a different silicon-containing film from the film EF to be etched. For example, the carbon-containing film may be a spin-on carbon (SOC) film, an amorphous carbon (ACL) film, a photoresist film, a tungsten carbide film, or a boron carbide film. For example, the metal-containing film may be a film containing at least one metal selected from the group consisting of tungsten, molybdenum, ruthenium, titanium, tin, and aluminum. In one embodiment, the mask MK may be a single-layer mask consisting of one layer, or it may be a multilayer mask consisting of two or more layers. If the mask MK is a multilayer mask, it may contain a silicon nitride film and a silicon oxide film, and the silicon oxide film may be formed to be thicker than the silicon nitride film. For example, the mask MK may be a multilayer mask containing a SiN film and a TEOS film in that order. In one embodiment, the mask MK may be a photoresist. In one embodiment, the mask MK may be a photoresist exposed to extreme ultraviolet light (EUV). For example, a metal-containing resist may be exposed to EUV. In one embodiment, the mask MK may be a chemically amplified resist (CAR). For example, a CAR may be exposed to EUV.

[0054] The aperture OP may have any shape when viewed in plan view of the substrate W, that is, when the substrate W is viewed from top to bottom in Figure 4. The shape may be, for example, a circle, an ellipse, a rectangle, a line, or a combination of one or more of these. The mask MK may have multiple side walls, and the multiple side walls may define multiple apertures OP. Each of the multiple apertures OP may have a linear shape and be arranged at regular intervals to form a line and space pattern. Alternatively, each of the multiple apertures OP may have a hole shape and form an array pattern. In one embodiment, the dimensions of the aperture OP may be 100 nm or less, 50 nm or less, or 30 nm or less. In one embodiment, the aperture OP may be formed by lithography. For example, the aperture OP may be formed by exposing and developing a photoresist formed on the etching target film EF. When EUV resist is used as the photoresist, exposure may be EUV exposure using an EUV exposure apparatus. Development may be dry development or wet development.

[0055] In step ST1, the substrate W may be prepared in the chamber 10. In one embodiment, the substrate W is transported into the chamber 10 by a transport arm, placed on the substrate support 11 by a lifter, and held by suction on the substrate support 11, for example as shown in Figure 2.

[0056] (Process ST2: Supply of processing gas) In process ST2, processing gas is supplied into the chamber 10. In the example in Figure 2, the processing gas may be supplied into the chamber 10 from a gas source 21 that stores the processing gas via a gas supply passage 23. For example, the processing gas may be supplied into the chamber 10 from, for example, a gas supply unit 20 via a gas inlet 13c of a central gas injection unit 13. In one embodiment, the global warming potential (GWP: 100-year value) of the processing gas may be 1000 or less, 100 or less, or 10 or less. Here, if the processing gas contains multiple types of gases, the GWP value of the processing gas is evaluated considering the volume ratio of each gas. For example, the GWP of a processing gas containing gas A (GWP value = a) and gas B (GWP value = b) in a volume ratio of X:Y can be calculated as a × X / (X + Y) + b × Y / (X + Y). The smaller the GWP value of the processing gas, the greater the contribution to improving the greenhouse effect, and therefore the lower the environmental burden in etching tends to be. From this perspective, the first, second, third, and fourth gases described below can be selected if they have small GWP values. There are no particular limitations on the evaluation criteria for GWP values, but for example, CF ４ The GWP value of the processed gas may be used as a reference. That is, the GWP value of the processed gas is CF ４ It may be smaller than the GWP value. In one embodiment, the processing gas includes a first gas and a second gas. The first gas is F ２ It is at least one selected from the group consisting of gas, fluorine-containing gas having a C-O bond, fluorine-containing gas having a C=O bond, fluorine-containing gas having a C=C bond, fluorine-containing gas having an N-O bond, and fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine. These are relatively easily decomposed in the atmosphere and tend to have low GWP values. As an example, a fluorine-containing gas having a C-O bond is CF ３ It may be OF, etc. As an example, a fluorine-containing gas having a C=O bond is COF. ２ , l-C ４ F ８ O, CHF ２ COF, CF ３It may be COF or the like. As an example, a fluorine-containing gas having a C═C bond is C ３ F ６ 、C ４ F ６ or the like. As an example, a fluorine-containing gas having an N—O bond is F ３ NO or the like. As an example, a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine is IF ７ or the like. In one embodiment, the first gas is F ２ 、CF ３ OF、COF ２ 、l-C ４ F ８ O、CHF ２ COF、CF ３ COF、C ３ F ６ 、C ４ F ６ 、F ３ NO、and IF ７ and includes at least one selected from the group consisting of. Also, the second gas is C ｍ H ｎ (where m represents an integer of m≥0 and n represents an integer of n≥2). The above m and n may be, for example, m = 0 and n = 2, or m = 1 and n = 4. In one embodiment, the second gas includes at least one selected from the group consisting of H ２ and CH ４ . In one embodiment, the first gas includes COF ２ , and the second gas includes H ２ . The fluorine atoms contained in the first gas and the hydrogen atoms contained in the second gas can each serve as a fluorine source and a hydrogen source for the HF plasma generated in step ST3 described later. Therefore, by using the processing gas containing the first gas and the second gas, HF plasma can be generated while reducing the environmental load.

[0057] In one embodiment, the processing gas is C ｘ H ｙ F ｚIt may contain a third gas represented by (where x represents an integer of 2 or more, y represents an integer of 1 or more, and z represents an integer of 1 or more). For example, the third gas may be, for example, C ２ HF ３ , C ２ HF ５ , C ２ H ２ F ２ , C ２ H ２ F ４ , C ２ H ３ F ３ , C ２ H ４ F ２ , C ２ H ５ F, C ３ HF ７ , C ３ H ２ F ２ , C ３ H ２ F ４ , C ３ H ２ F ６ , C ３ H ３ F ５ , C ４ H ２ F ６ , C ４ H ５ F ５ , C ４ H ２ F ８ , C ５ H ２ F ６ , C ５ H ２ F １０ , C ５ H ３ F ７ These may be, etc. In one embodiment, the third gas is C ２ H ２ F ２ , C ２ HF ３ , C ２ H ５ F, C ３ H ２ F ４ and C ４ H ２ F６ It includes at least one selected from the group consisting of the following. The fluorine atoms and hydrogen atoms contained in the third gas may be the fluorine source and hydrogen source of the HF plasma that can be generated in step ST3 described later. In one embodiment, the processing gas may include the third gas in addition to the first gas and the second gas, or it may include the third gas in place of the first gas and the second gas.

[0058] In one embodiment, the processing gas is HF gas, phosphorus-containing gas, nitrogen gas, NH ３ Gas, H ２ It may contain at least one fourth gas selected from the group consisting of O gas, halogen-containing gases, and metal-containing gases. For example, phosphorus-containing gases include PF ３ , PF ５ , POCl ３ and PCL ３ These may be, for example, halogen-containing gases such as HBr, HCl, and BCl. ３ For example, metal-containing gases include SnCl. ４ WF ６ WCl ６ MoF ６ These may be, etc. In one embodiment, the phosphorus-containing gas is PF ３ , PF ５ and PCL ３ It includes at least one selected from the group consisting of HCl and BCl. In one embodiment, the halogen-containing gas is HCl and BCl. ３ It includes at least one selected from the group consisting of WF. In one embodiment, the metal-containing gas is WF ６ WCl ６ and MoF ６ It includes at least one selected from the group consisting of the following.

[0059] In one embodiment, the processing gas may include gases other than the first gas, second gas, third gas, and fourth gas. For example, the processing gas may be C ４ F ６The gas may contain carbon atoms and fluorine atoms. For example, the processed gas may contain noble gases such as Ar. In one embodiment, the sum of the flow rates of the first gas and the second gas relative to the total flow rate of the processed gas excluding the noble gas may be 80% by volume or more. For example, the sum of the flow rates of the first gas and the second gas may be 100 sccm or more. In one embodiment, the flow rate of the first gas is greater than the flow rate of the HF gas. For example, the flow rate of the HF gas may be 500 sccm or less.

[0060] (Step ST3: Etching) In step ST3, the film EF to be etched is etched by plasma generated from the processing gas through the mask MK. In one embodiment, in step ST3, HF plasma may be generated using fluorine atoms contained in the first gas supplied into the chamber 10 in step ST2 as a fluorine source and hydrogen atoms contained in the second gas as a hydrogen source.

[0061] In one embodiment, a source RF signal is supplied to the antenna 14, thereby generating a high-frequency electric field between the antenna 14 and the substrate support 11, and generating plasma from the processing gas in the plasma processing space 10s. At this time, a bias signal may be supplied to the substrate support 11. The bias signal may be a bias RF signal supplied from an RF power supply 31 or a bias DC signal supplied from a DC power supply 32. In this case, a bias potential is generated between the plasma and the substrate W. Active species such as ions and radicals in the plasma are attracted to the substrate W, and the etching target film EF is etched by these active species. In one embodiment, the power of the source RF signal may be 500W or more. In one embodiment, the power of the bias signal may be 500W or less. The pressure in the chamber 10 may be adjusted to a set pressure. The set pressure may be 15mTorr or more and 200mTorr or less.

[0062] Figure 5 shows an example of the cross-sectional structure of the substrate W after performing steps ST2 and ST3. In step ST3, the mask MK functions as a mask. That is, the portion of the film EF to be etched that is exposed to the opening OP is selectively etched by active species in the plasma. As a result, a recess RC is formed as shown in Figure 5. In step ST3, because the processing gas contains the first gas and the second gas, there is a tendency for active species of hydrogen fluoride to be generated in the resulting plasma, thereby ensuring etching performance. In one embodiment, the selectivity ratio can be improved. In one embodiment, the etching rate can be improved.

[0063] (Modified Version) Figure 6 shows a modified version of the inductively coupled plasma processing apparatus. In the example in Figure 6, the gas supply unit 20 is configured to supply HF gas and gases other than HF gas separately to the chamber 10. That is, the gas supply unit 20 includes a gas source 21a for storing gases other than HF gas and a gas source 21b for storing HF gas. The gas stored in the gas source 21a may be at least one selected from the group consisting of a first gas, a second gas, a third gas, a fourth gas (excluding HF gas), and a noble gas. The first supply path 23a connected to the gas source 21a is a path for supplying gases other than HF gas into the chamber. A flow rate controller 22a is provided in the first supply path 23a, which may be used to adjust the flow rate of gases other than HF gas. On the other hand, the second supply path 23b connected to the gas source 21b is a path for supplying HF gas into the chamber. A flow rate controller 22b may be provided in the second supply passage 23b to adjust the flow rate of HF gas. In one embodiment, the gas source 21b may contain HF in liquid state. A vaporizer 24 and a heater (not shown) may also be provided in the second supply passage 23b. For example, the gas source 21b may be configured to maintain the HF at 50°C or below, and the vaporizer 24 may be configured to raise the temperature of the HF to 50°C or above. In one embodiment, the constituent material of the second supply passage may have higher corrosion resistance than the constituent material of the first supply passage. In this case, the risk of corrosion of the supply path due to HF can be reduced.

[0064] <Examples> Next, specific examples of etching performance evaluated based on this etching method will be described. This disclosure is not limited in any way by the following examples.

[0065] (Reference Example 1) An apparatus having the same configuration as the plasma processing apparatus 1 shown in Figure 2 was prepared. A substrate was placed on the substrate support part 11 of the apparatus. This substrate had the same configuration as the substrate W shown in Figure 4. A silicon oxide film was used as the film EF to be etched. Multiple openings OP were formed in the mask MK to expose the film EF to be etched. That is, the multiple openings OP were formed to constitute a contact hole pattern.

[0066] Etching was performed in the plasma processing apparatus 1 under the following conditions to form a contact hole pattern: Processing gas: HF gas 200 sccm, PF ３ Gas 10 sccm, Ar gas 50 sccm. Source RF signal: 27 MHz, 300 W. Bias RF signal: 13 MHz, 500 W.

[0067] Based on the above results, the appearance of the pattern (shape of the recesses formed by etching) was good, and the etching selectivity ratio was 1.8.

[0068] (Example 1) The contact hole pattern was formed in the same manner as in Reference Example 1, except that the conditions were changed as follows: Processing gas: COF ２ Gas 100 sccm, H ２ Gas 100 sccm, PF ３ Gas 10 sccm, Ar gas 50 sccm

[0069] As a result of the above, the pattern appearance was good, similar to Reference Example 1, and the etching selectivity ratio was 1.8. Compared with Reference Example 1, in Example 1, etching was possible with a low GWP processing gas while maintaining the etching selectivity ratio. Thus, COF ２ Gas and H ２It was evaluated that using gas can reduce the environmental impact of etching without impairing etching performance. Furthermore, under the conditions of Example 1, when only the power of the source RF signal was changed (from 300W to 1000W), the etching rate of the target film increased by 1.5 times.

[0070] (Reference Example 2) Except for changing the etching target film EF in Reference Example 1 to a silicon nitride film and changing the mask MK to SOC, the substrate was placed on the substrate support part 11 of the plasma processing apparatus 1 in the same manner as in Reference Example 1.

[0071] Etching was performed in the plasma processing apparatus 1 under the following conditions to form a line-and-space pattern. Processing gas: CH ３ F gas 45 sccm, O ２ Gas 10 sccm, Ar gas 300 sccm. Source RF signal: 27 MHz, 300 W. Bias RF signal: 13 MHz, 300 W.

[0072] Based on the above results, the appearance of the pattern was good.

[0073] (Example 2) A line-and-space pattern was formed in the same manner as in Reference Example 2, except that the conditions were changed as follows: Processing gas: COF ２ Gas 31 sccm, C ４ F ６ Gas 8 sccm, H ２ Gas 16 sccm, Ar gas 300 sccm

[0074] As a result of the above, the pattern appearance was good, similar to Reference Example 2. In Example 2, COF ２ Gas and H ２ The use of gas was evaluated as a way to reduce the environmental impact of etching without compromising etching performance.

[0075] (Reference Example 3) Except for changing the etching target film EF in Reference Example 1 to a silicon oxynitride film and changing the mask MK to SOC, the substrate was placed on the substrate support part 11 of the plasma processing apparatus 1 in the same manner as in Reference Example 1.

[0076] Etching was performed in the plasma processing apparatus 1 under the following conditions to form a contact hole pattern. Processing gas: CH ３ F gas 35 sccm, CHF ３ Gas 17 sccm, NF ３ Gas 50 sccm, N ２ Gas 140 sccm, Ar gas 600 sccm. Source RF signal: 27 MHz, 2000 W. Bias RF signal: 13 MHz, 80 W.

[0077] Based on the above results, the appearance of the pattern was good.

[0078] (Example 3) The contact hole pattern was formed in the same manner as in Reference Example 3, except that the conditions were changed as follows: Processing gas: COF ２ Gas 100 sccm, H ２ Gas 100 sccm, C ３ H ２ F ４ Gas 550 sccm, Ar gas 300 sccm

[0079] As a result of the above, the pattern appearance was good, similar to Reference Example 3. In Example 3, COF ２ Gas and H ２ The use of gas was evaluated as a way to reduce the environmental impact of etching without compromising etching performance.

[0080] Embodiments of this disclosure further include the following embodiments:

[0081] (Note 1) (a) A step of preparing a substrate on a substrate support in a chamber including a substrate support, wherein the substrate comprises an etching target film comprising at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, the mask having at least one opening that exposes the etching target film; (b) A step of supplying a processing gas into the chamber, wherein the processing gas is F ２A first gas selected from the group consisting of gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and C ｍ H ｎ (c) an etching method comprising: (a) a step of etching the film to be etched through the opening with plasma generated from the processing gas, (c) a step of etching the film to be etched through the opening with plasma generated from the processing gas.

[0082] (Note 2) The first gas is F ２ CF ３ OF, COF ２ , l-C ４ F ８ O, CHF ２ COF, CF ３ COF, C ３ F ６ , C ４ F ６ F ３ NO, and IF ７ The etching method described in Appendix 1, comprising at least one selected from the group consisting of the following.

[0083] (Note 3) The second gas is H ２ and CH ４ The etching method according to Appendix 1 or 2, comprising at least one selected from the group consisting of the following.

[0084] (Note 4) The first gas is COF ２ The second gas includes H ２ An etching method described in any one of the appendices 1 to 3, including the method described in appendices 1 to 3.

[0085] (Note 5) The processing gas is C ｘ H ｙ F ｚ The etching method according to any one of the appendices 1 to 4, further comprising a third gas represented by (where x represents an integer of 2 or more, y represents an integer of 1 or more, and z represents an integer of 1 or more).

[0086] (Note 6) The third gas is C ２ H ２ F ２ , C ２ HF ３ , C ２ H ５ F, C ３ H ２ F ４ and C ４ H ２ F ６ The etching method described in Appendix 5, comprising at least one selected from the group consisting of the following.

[0087] (Note 7) The processing gases include HF gas, phosphorus-containing gas, nitrogen gas, and NH ３ Gas, H ２ The etching method according to any one of the appendices 1 to 6, further comprising at least one fourth gas selected from the group consisting of O gas, halogen-containing gas, and metal-containing gas.

[0088] (Note 8) The etching method according to Note 7, wherein the flow rate of the first gas is greater than the flow rate of the HF gas.

[0089] (Note 9) The etching method according to Note 7 or 8, wherein the flow rate of the HF gas is 500 sccm or less.

[0090] (Note 10) The phosphorus-containing gas is PF ３ , PF ５ , POCl ３ and PCL ３ The halogen-containing gas comprises at least one selected from the group consisting of HBr, HCl and BCl ３ The metal-containing gas comprises at least one selected from the group consisting of SnCl ４ WF ６ WCl ６ and MoF ６ An etching method according to any one of appendices 7 to 10, comprising at least one selected from the group consisting of the following.

[0091] (Note 11) The etching method according to any one of Notes 1 to 10, wherein the plasma in (c) is generated by supplying a source RF signal to the plasma generation unit.

[0092] (Note 12) The films to be etched are silicon oxide film, silicon nitride film, silicon oxynitride film, low dielectric constant film, Al ２ O ３ membrane, ZrO ２ membrane, HfO ２ An etching method according to any one of the appendices 1 to 11, comprising at least one selected from the group consisting of a film, an IGZO film, a Pt-containing film, and a Ru-containing film.

[0093] (Note 13) The apparatus comprises: a chamber; a substrate support provided in the chamber; an electrostatic chuck provided in the substrate support; a gas supply unit configured to supply a processing gas into the chamber; a plasma generation unit configured to generate plasma from the processing gas; and a control unit, wherein the control unit includes: (a) a control for holding the substrate on the substrate support by the electrostatic chuck, wherein the substrate comprises an etching target film including at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, wherein the mask has at least one opening that exposes the etching target film; and (b) a control for supplying the processing gas into the chamber by the gas supply unit, wherein the processing gas is F ２ A first gas selected from the group consisting of gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and C ｍ H ｎ A plasma processing apparatus configured to perform a control including (c) a control for etching the target film with the plasma generated from the processing gas by the plasma generation unit, which includes a second gas represented by (c) a second gas represented by (m) a second gas represented by (c) a second gas represented by (m) a second gas represented by (c) a second gas represented by (d) a second gas represented by (c

[0094] (Note 14) The plasma processing apparatus according to Note 13, wherein the processing gas further contains HF gas, and the gas supply unit includes a first supply path configured to supply a gas other than the HF gas from the processing gas, and a second supply path configured to supply the HF gas.

[0095] (Note 15) The plasma processing apparatus according to Note 14, wherein the second supply channel is connected to a gas source containing HF in liquid state.

[0096] (Note 16) The plasma processing apparatus described in Note 15, wherein the second supply channel includes a vaporizer and a heater.

[0097] (Note 17) The plasma processing apparatus according to Note 16, wherein the constituent material of the second supply channel has higher corrosion resistance than the constituent material of the first supply channel.

[0098] (Note 18) The first gas is COF ２ The second gas includes H ２ A plasma processing apparatus as described in any one of appendices 13 to 17, including the one described in appendices 13 to 17.

[0099] (Note 19) The plasma processing apparatus according to any one of Notes 13 to 18, wherein the control unit in (c) above is configured to perform control to supply a source RF signal to the substrate support unit.

[0100] (Note 20) The plasma processing apparatus according to any one of Notes 14 to 19, wherein in (b) above, the flow rate of the first gas is greater than the flow rate of the HF gas.

[0101] The embodiments described above are for illustrative purposes only and are not intended to limit the scope of this disclosure. Each embodiment can be modified in various ways without departing from the scope and spirit of this disclosure. For example, some components of one embodiment can be added to other embodiments, or some components of one embodiment can be replaced with corresponding components of other embodiments.

[0102] 1...Plasma processing apparatus, 2...Control unit, 10...Plasma processing chamber, 11...Substrate support unit, 12...Plasma generation unit, 20...Gas supply unit, 21...Gas source, 21a...Gas source, 21b...Gas source, 23...Gas supply path, 23a...First supply path, 23b...Second supply path, 24...Vaporizer, 1111...Electrostatic chuck, W...Substrate, UF...Undercoat, EF...Etching target film, MK...Mask, OP...Opening, RC...Recess

Claims

1. (a) A step of preparing a substrate on a substrate support in a chamber including a substrate support, wherein the substrate comprises an etching target film comprising at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, the mask having at least one opening that exposes the etching target film; (b) A step of supplying a processing gas into the chamber, wherein the processing gas is F ２ A first gas selected from the group consisting of gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and C ｍ H ｎ (c) an etching method comprising: (a) a step of etching the film to be etched through the opening with plasma generated from the processing gas, (c) a step of etching the film to be etched through the opening with plasma generated from the processing gas.

2. The first gas contains at least one selected from the group consisting of F ２ , CF ３ OF, COF ２ , l-C ４ F ８ O, CHF ２ COF, CF ３ COF, C ３ F ６ , C ４ F ６ , F ３ NO, and IF ７ , and the etching method according to claim 1 3. The second gas is H ２ and CH ４ The etching method according to claim 1, comprising at least one selected from the group consisting of the following.

4. The first gas is COF ２ The second gas includes H ２ The etching method according to claim 1, including the following:

5. The processing gas is C ｘ H ｙ F ｚ The etching method according to claim 1, further comprising a third gas represented by (wherein x represents an integer of 2 or more, y represents an integer of 1 or more, and z represents an integer of 1 or more).

6. The third gas is C ２ H ２ F ２ , C ２ HF ３ , C ２ H ５ F, C ３ H ２ F ４ and C ４ H ２ F ６ The etching method according to claim 5, comprising at least one selected from the group consisting of the following.

7. The processing gas is HF gas, phosphorus-containing gas, nitrogen gas, NH ３ Gas, H ２ The etching method according to claim 1, further comprising at least one fourth gas selected from the group consisting of O gas, halogen-containing gases, and metal-containing gases.

8. The etching method according to claim 7, wherein the flow rate of the first gas is greater than the flow rate of the HF gas.

9. The etching method according to claim 8, wherein the flow rate of the HF gas is 500 sccm or less.

10. The phosphorus-containing gas is PF ３ , PF ５ , POCl ３ and PCL ３ The halogen-containing gas comprises at least one selected from the group consisting of HBr, HCl and BCl ３ The metal-containing gas comprises at least one selected from the group consisting of SnCl ４ WF ６ WCl ６ and MoF ６ The etching method according to claim 7, comprising at least one selected from the group consisting of the following.

11. The etching method according to any one of claims 1 to 9, wherein the plasma in (c) is generated by supplying a source RF signal to a plasma generation unit.

12. The films to be etched include silicon oxide films, silicon nitride films, silicon oxynitride films, low dielectric constant films, and Al ２ O ３ membrane, ZrO ２ membrane, HfO ２ The etching method according to any one of claims 1 to 9, comprising at least one selected from the group consisting of a film, an IGZO film, a Pt-containing film, and a Ru-containing film.

13. The apparatus comprises: a chamber; a substrate support provided within the chamber; an electrostatic chuck provided on the substrate support; a gas supply unit configured to supply a processing gas into the chamber; a plasma generation unit configured to generate plasma from the processing gas; and a control unit, wherein the control unit includes: (a) a control for holding the substrate on the substrate support by the electrostatic chuck, wherein the substrate comprises an etching target film including at least one selected from the group consisting of silicon and metal, and a mask on the etching target film, wherein the mask has at least one opening that exposes the etching target film; and (b) a control for supplying the processing gas into the chamber by the gas supply unit, wherein the processing gas is F ２ A first gas selected from the group consisting of gas, a fluorine-containing gas having a C-O bond, a fluorine-containing gas having a C=O bond, a fluorine-containing gas having a C=C bond, a fluorine-containing gas having an N-O bond, and a fluorine-containing gas having a fluorine atom and a halogen atom other than fluorine, and C ｍ H ｎ A plasma processing apparatus configured to perform a control including (c) a control for etching the target film with the plasma generated from the processing gas by the plasma generation unit, which includes a second gas represented by (c) a second gas represented by (m) a second gas represented by (c) a second gas represented by (m) a second gas represented by (c) a second gas represented by (d) a second gas represented by (c 14. The plasma processing apparatus according to claim 13, wherein the processing gas further comprises HF gas, and the gas supply unit includes a first supply path configured to supply a gas other than the HF gas from the processing gas, and a second supply path configured to supply the HF gas.

15. The plasma processing apparatus according to claim 14, wherein the second supply channel is connected to a gas source containing HF in liquid state.

16. The plasma processing apparatus according to claim 15, wherein the second supply channel includes a vaporizer and a heater.

17. The plasma processing apparatus according to claim 16, wherein the constituent material of the second supply channel has higher corrosion resistance than the constituent material of the first supply channel.

18. The first gas is COF ２ The second gas includes H ２ A plasma processing apparatus according to any one of claims 13 to 17, including the following:

19. The plasma processing apparatus according to any one of claims 13 to 17, wherein the control unit is configured to perform control to supply a source RF signal to the substrate support unit in (c) above.

20. The plasma processing apparatus according to any one of claims 14 to 17, wherein, in (b) above, the flow rate of the first gas is greater than the flow rate of the HF gas.

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