Substrate Processing Equipment

Abstract

To provide a substrate processing method, a component processing method, and a substrate processing device, that can remove a substance existing on a surface of a substrate or a component.SOLUTION: In one illustrative embodiment, a method of processing a substrate on a substrate support part disposed in a chamber of a substrate processing device is provided. The method includes the steps of: (a) supplying a process gas including a hydrogen fluoride gas into the chamber; (b) controlling the temperature of the substrate support part to a first temperature and the pressure of the hydrogen fluoride gas in the chamber to a first pressure; and (c) controlling the temperature of the substrate support part to a second temperature and the pressure of the hydrogen fluoride gas in the chamber to a second pressure. In a graph whose horizontal axis is temperature and vertical axis is pressure, the first temperature and the first pressure exist in a first region above an adsorption equilibrium curve of the hydrogen fluoride, and the second temperature and the second pressure exist in a second region below the adsorption equilibrium curve.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] SUMMARY Exemplary embodiments of the present disclosure relate to substrate processing methods, component processing methods, and substrate processing apparatus. [Background technology]

[0002] Patent Document 1 discloses a method for removing etching residues adhering to a semiconductor substrate using a stripping solution containing fluorine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-188139 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a substrate processing method, a component processing method, and a substrate processing apparatus that can remove substances present on the surface of a substrate or component. [Means for solving the problem]

[0005] In one exemplary embodiment, a method for processing a substrate on a substrate support disposed in a chamber of a substrate processing apparatus is provided, the method including: (a) supplying a process gas containing hydrogen fluoride gas into the chamber; (b) controlling the temperature of the substrate support at a first temperature and the pressure of the hydrogen fluoride gas in the chamber at a first pressure; and (c) controlling the temperature of the substrate support at a second temperature and the pressure of the hydrogen fluoride gas in the chamber at a second pressure. In a graph with temperature on the horizontal axis and pressure on the vertical axis, the first temperature and the first pressure are located in a first region above an adsorption equilibrium pressure curve for hydrogen fluoride, and the second temperature and the second pressure are located in a second region below the adsorption equilibrium pressure curve. [Effects of the Invention]

[0006] According to one exemplary embodiment, a substrate processing method, a component processing method, and a substrate processing apparatus are provided that are capable of removing material present on the surface of a substrate or component. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram schematically illustrating a substrate processing apparatus according to an exemplary embodiment. [Figure 2] FIG. 2 is a schematic diagram of a substrate processing apparatus according to an exemplary embodiment. [Figure 3] FIG. 3 is a partial enlarged view of a substrate processing apparatus according to an exemplary embodiment. [Figure 4] FIG. 4 is a flowchart of a substrate processing method according to one exemplary embodiment. [Figure 5] FIG. 5 is a partially enlarged cross-sectional view of an example substrate to which a substrate processing method according to an exemplary embodiment can be applied. [Figure 6] FIG. 6 is a graph showing an example of an adsorption equilibrium pressure curve and a saturated vapor pressure curve of hydrogen fluoride. [Figure 7] FIG. 7 is a partially enlarged cross-sectional view of an example substrate in which hydrogen fluoride is adsorbed on the surface of the substrate. [Figure 8] FIG. 8 is a partially enlarged cross-sectional view of an example of a substrate when adsorbed hydrogen fluoride is desorbed. [Figure 9] FIG. 9 is a plan view of an example substrate having a surface with a substance deposited thereon, the substance being generated by a substrate processing apparatus. [Figure 10] FIG. 10 is a flowchart of a part processing method according to one exemplary embodiment. [Figure 11] FIG. 11 is a partially enlarged cross-sectional view of an example substrate to which a substrate processing method according to an exemplary embodiment can be applied. [Figure 12] FIG. 12 is a partially enlarged cross-sectional view of an example substrate in which hydrogen fluoride is adsorbed on the surface of the substrate. [Figure 13]FIG. 13 is a partially enlarged cross-sectional view of an example of a substrate when adsorbed hydrogen fluoride is desorbed. [Figure 14] 14(a) and 14(b) are partially enlarged plan views of the surface of an example substrate. [Figure 15] FIG. 15 is a graph showing an example of the relationship between the pressure of hydrogen fluoride gas and the etching amount. [Figure 16] FIG. 16 is a graph showing an example of the relationship between the temperature of the substrate support and the etching amount. [Figure 17] FIG. 17 is a graph showing an example of the relationship between the adsorption time and the thickness of the mask or the size of the opening in the mask. [Figure 18] FIG. 18 is a graph showing an example of the relationship between temperature and the rate of decrease in the thickness of the mask or the rate of increase in the size of the openings in the mask. [Figure 19] FIG. 19 is a graph showing an example of the relationship between pressure and the rate of decrease in the thickness of the mask or the rate of increase in the size of the opening in the mask. [Figure 20] FIG. 20 is a flowchart of a substrate processing method according to one exemplary embodiment. [Figure 21] FIG. 21 is a diagram schematically illustrating a substrate processing apparatus according to an exemplary embodiment. [Figure 22] FIG. 22 is a graph showing an example of the relationship between the depth of the recess and the size of the recess. [Figure 23] FIG. 23 is a graph showing an example of the positions of the openings in the mask. [Figure 24] FIG. 24 is an enlarged cross-sectional view of a portion of an example substrate. DETAILED DESCRIPTION OF THE INVENTION

[0008] Various exemplary embodiments are described below.

[0009] In one exemplary embodiment, a method for processing a substrate on a substrate support disposed in a chamber of a substrate processing apparatus is provided, the method including: (a) supplying a process gas containing hydrogen fluoride gas into the chamber; (b) controlling the temperature of the substrate support at a first temperature and the pressure of the hydrogen fluoride gas in the chamber at a first pressure; and (c) controlling the temperature of the substrate support at a second temperature and the pressure of the hydrogen fluoride gas in the chamber at a second pressure. In a graph with temperature on the horizontal axis and pressure on the vertical axis, the first temperature and the first pressure are located in a first region above an adsorption equilibrium pressure curve for hydrogen fluoride, and the second temperature and the second pressure are located in a second region below the adsorption equilibrium pressure curve.

[0010] According to the method of the above embodiment, when substances such as etching residues or particles are present on the surface of the substrate, the substances can be removed together with the desorption of hydrogen fluoride.

[0011] In the graph, the first region may be located below the saturated vapor pressure curve of hydrogen fluoride. The first temperature and the second temperature may be in the range of -140°C or more and 0°C or less, and the first pressure and the second pressure may be in the range of 1 Pa or more and 1×10 5 It may be in the range of Pa or less.

[0012] The substrate may include a silicon-containing film. In this case, substances generated from the silicon-containing film can be removed along with the desorption of hydrogen fluoride.

[0013] The substrate may include a metal-containing film. In this case, substances generated from the metal-containing film can be removed along with the desorption of hydrogen fluoride.

[0014] In the step (b), a substance generated in the substrate processing apparatus may be attached to the surface of the substrate, and in this case, the substance generated in the substrate processing apparatus can be removed together with the desorption of hydrogen fluoride.

[0015] The processing gas may contain an inert gas, in which case the amount of material removed can be adjusted by adjusting the flow rate ratio of the inert gas.

[0016] In one exemplary embodiment, a method for processing a component disposed in a chamber of a substrate processing apparatus is provided, the method including: (a) supplying a process gas containing hydrogen fluoride gas into the chamber; (b) controlling the temperature of the component at a first temperature and the pressure of the hydrogen fluoride gas in the chamber at a first pressure; and (c) controlling the temperature of the component at a second temperature and the pressure of the hydrogen fluoride gas in the chamber at a second pressure. In a graph with temperature on the horizontal axis and pressure on the vertical axis, the first temperature and the first pressure are located in a first region above an adsorption equilibrium pressure curve for hydrogen fluoride, and the second temperature and the second pressure are located in a second region below the adsorption equilibrium pressure curve.

[0017] According to the method of the above embodiment, if substances such as etching residues or particles are present on the surface of the component, the substances can be removed while hydrogen fluoride is desorbed.

[0018] In one exemplary embodiment, a substrate processing apparatus is provided, comprising: a chamber; a substrate support for supporting a substrate in the chamber; a gas supply unit configured to supply a process gas containing hydrogen fluoride gas into the chamber; and a controller, wherein the controller is configured to control the temperature of the substrate support to a first temperature, the pressure of the hydrogen fluoride gas in the chamber to a first pressure, and the temperature of the substrate support to a second temperature, and the pressure of the hydrogen fluoride gas in the chamber to a second pressure. In a graph with temperature on the horizontal axis and pressure on the vertical axis, the first temperature and the first pressure are located in a first region above an adsorption equilibrium pressure curve for hydrogen fluoride, and the second temperature and the second pressure are located in a second region below the adsorption equilibrium pressure curve.

[0019] According to the substrate processing apparatus of the above embodiment, when substances such as etching residues or particles are present on the surface of the substrate, the substances can be removed together with the desorption of hydrogen fluoride.

[0020] In one exemplary embodiment, a method for processing a substrate is provided, the method including: (a) providing the substrate with an underlayer and a mask overlying the underlayer and having an opening; (b) etching the underlayer using plasma; and (c) supplying hydrogen fluoride to the mask to remove deposits deposited in the opening of the mask by (b).

[0021] According to the method of the above embodiment, in (c), the deposits can be removed by hydrogen fluoride.

[0022] In the step (c), hydrogen fluoride gas may be supplied without generating plasma, in which case etching of the mask by plasma is suppressed.

[0023] In the step (c), hydrofluoric acid may be supplied, in which case the deposits can be removed by the hydrofluoric acid.

[0024] The method may further include (d) etching the base film using plasma after (c). In this case, deposits are removed in (c). Therefore, recesses having a desired shape can be formed in the base film by subsequent etching.

[0025] The method may further include (e) supplying hydrogen fluoride to the mask after (d) so as to remove deposits that have adhered to the openings of the mask by (d). In this case, the deposits can be removed by hydrogen fluoride in (e).

[0026] The mask may comprise silicon.

[0027] The undercoat film may contain carbon.

[0028] In one exemplary embodiment, a substrate processing apparatus is provided, the substrate processing apparatus comprising: a chamber; a substrate support for supporting a substrate in the chamber, the substrate including an underlayer and a mask disposed on the underlayer and having an opening; a gas supply unit configured to supply a first process gas and a second process gas including hydrogen fluoride gas into the chamber; a plasma generator configured to generate plasma from the first process gas in the chamber; and a controller, wherein the controller is configured to control the gas supply unit and the plasma generator to etch the underlayer using the plasma, and the controller is configured to control the gas supply unit to supply the second process gas to the mask so as to etch the underlayer and thereby remove deposits adhering to the opening in the mask.

[0029] According to the substrate processing apparatus of the above embodiment, deposits can be removed by the second processing gas containing hydrogen fluoride gas.

[0030] In one exemplary embodiment, a substrate processing apparatus is provided, the substrate processing apparatus comprising: a chamber; a substrate support for supporting a substrate in the chamber, the substrate including an underlayer and a mask having an opening disposed on the underlayer; a gas supply unit configured to supply a first process gas into the chamber; a plasma generation unit configured to generate plasma from the first process gas in the chamber; a wet processing apparatus including a container for containing hydrofluoric acid; and a controller, wherein the controller is configured to control the gas supply unit and the plasma generation unit to etch the underlayer using the plasma, and the controller is configured to control the wet processing apparatus to supply the hydrofluoric acid to the mask to etch the underlayer using the plasma, thereby removing deposits adhering to the opening in the mask.

[0031] According to the substrate processing apparatus of the above embodiment, deposits can be removed by hydrofluoric acid.

[0032] Various exemplary embodiments will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0033] 1 and 2 are diagrams schematically illustrating a substrate processing apparatus according to an exemplary embodiment, which is, for example, a plasma processing system.

[0034] In one embodiment, the plasma processing system includes a plasma processing device 1 and a controller 2. The plasma processing device 1 includes a plasma processing chamber 10, a substrate support 11, and a plasma generation unit 12. The plasma processing chamber 10 has a plasma processing space. The plasma processing chamber 10 also has at least one gas supply port for supplying at least one processing gas to the plasma processing space and at least one gas exhaust port for exhausting gas from the plasma processing space. The gas supply port is connected to a gas supply unit 20 (described later), and the gas exhaust port is connected to an exhaust system 40 (described later). The substrate support 11 is disposed in the plasma processing space and has a substrate support surface for supporting a substrate.

[0035] The plasma generating unit 12 is configured to generate plasma from at least one processing gas supplied into the plasma processing space. The plasma formed in the plasma processing space may be capacitively coupled plasma (CCP), inductively coupled plasma (ICP), electron-cyclotron-resonance plasma (ECR plasma), helicon wave plasma (HWP), or surface wave plasma (SWP). Various types of plasma generating units may be used, including alternating current (AC) plasma generating units and direct current (DC) plasma generating units. In one embodiment, the AC signal (AC power) used in the AC plasma generating unit has a frequency in the range of 100 kHz to 10 GHz. Therefore, the AC signal includes a radio frequency (RF) signal and a microwave signal. In one embodiment, the RF signal has a frequency in the range of 200 kHz to 150 MHz.

[0036] The controller 2 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform various processes described in this disclosure. The controller 2 may be configured to control each element of the plasma processing apparatus 1 to perform various processes described herein. In one embodiment, part or all of the controller 2 may be included in the plasma processing apparatus 1. The controller 2 may include, for example, a computer 2a. The computer 2a may include, for example, a processing unit (CPU: Central Processing Unit) 2a1, a storage unit 2a2, and a communication interface 2a3. The processing unit 2a1 may be configured to perform various control operations based on programs stored in the storage unit 2a2. The storage unit 2a2 may include a random access memory (RAM), a read-only memory (ROM), a hard disk drive (HDD), a solid state drive (SSD), or a combination thereof. The communication interface 2a3 may communicate with the plasma processing apparatus 1 via a communication line such as a local area network (LAN).

[0037] An example of the configuration of a plasma processing system will be described below. The plasma processing system includes a capacitively coupled plasma processing apparatus 1 and a controller 2. The capacitively coupled plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply 20, a power supply 30, and an exhaust system 40. The plasma processing apparatus 1 also includes a substrate support 11 and a gas inlet. The gas inlet is configured to introduce at least one process gas into the plasma processing chamber 10. The gas inlet includes a showerhead 13. The substrate support 11 is disposed within the plasma processing chamber 10. The showerhead 13 is disposed above the substrate support 11. In one embodiment, the showerhead 13 forms at least a portion of the ceiling of the plasma processing chamber 10. The plasma processing chamber 10 has a plasma processing space 10s defined by the showerhead 13, a sidewall 10a of the plasma processing chamber 10, and the substrate support 11. The plasma processing chamber 10 has at least one gas inlet for supplying at least one process gas to the plasma processing space 10s and at least one gas outlet for exhausting gas from the plasma processing space 10s. The sidewall 10a is grounded. The showerhead 13 and the substrate support 11 are electrically isolated from the plasma processing chamber 10 housing.

[0038] The substrate support 11 includes a main body 111 and a ring assembly 112. The main body 111 has a central region (substrate support surface) 111a for supporting a substrate (wafer) W and an annular region (ring support surface) 111b for supporting the ring assembly 112. The annular region 111b of the main body 111 surrounds the central region 111a of the main body 111 in a plan view. The substrate W is disposed on the central region 111a of the main body 111, and the ring assembly 112 is disposed on the annular region 111b of the main body 111 so as to surround the substrate W on the central region 111a of the main body 111. In one embodiment, the main body 111 includes a base and an electrostatic chuck. The base includes a conductive member. The conductive member of the base functions as a lower electrode. The electrostatic chuck is disposed on the base. The upper surface of the electrostatic chuck has the substrate support surface 111a. The ring assembly 112 includes one or more annular members. At least one of the one or more annular members is an edge ring. Although not shown, the substrate support 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck, 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, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. The substrate support 11 may also include a heat transfer gas supply unit configured to supply a heat transfer gas between the back surface of the substrate W and the substrate support surface 111a.

[0039] The showerhead 13 is configured to introduce at least one processing gas from the gas supply unit 20 into the plasma processing space 10s. The showerhead 13 has at least one gas supply port 13a, at least one gas diffusion chamber 13b, and multiple gas inlets 13c. The processing gas supplied to the gas supply port 13a passes through the gas diffusion chamber 13b and is introduced into the plasma processing space 10s from the multiple gas inlets 13c. The showerhead 13 also includes a conductive member. The conductive member of the showerhead 13 functions as an upper electrode. In addition to the showerhead 13, the gas introduction unit may also include one or more side gas injectors (SGIs) attached to one or more openings formed in the sidewall 10a.

[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 process gas from a corresponding gas source 21 to the showerhead 13 via a corresponding flow controller 22. Each flow controller 22 may include, for example, a mass flow controller or a pressure-controlled flow controller. Additionally, the gas supply unit 20 may include one or more flow modulation devices to modulate or pulse the flow rate of the at least one process gas.

[0041] The power supply 30 includes an RF power supply 31 coupled to the plasma processing chamber 10 via at least one impedance matching circuit. The RF power supply 31 is configured to supply at least one RF signal (RF power), such as a source RF signal and a bias RF signal, to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13. This causes plasma to be formed from at least one process gas supplied to the plasma processing space 10s. Therefore, the RF power supply 31 can function as at least a part of a plasma generating unit configured to generate plasma from one or more process gases in the plasma processing chamber 10. Furthermore, supplying a bias RF signal to the conductive members of the substrate support 11 generates a bias potential on the substrate W, thereby attracting ion components in the formed plasma to the substrate W.

[0042] In one embodiment, the RF power supply 31 includes a first RF generating unit 31a and a second RF generating unit 31b. The first RF generating unit 31a is coupled to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13 via at least one impedance matching circuit and is configured to generate a source RF signal (source RF power) for plasma generation. In one embodiment, the source RF signal has a frequency in the range of 13 MHz to 150 MHz. In one embodiment, the first RF generating unit 31a may be configured to generate multiple source RF signals having different frequencies. The generated one or more source RF signals are supplied to the conductive members of the substrate support 11 and / or the conductive members of the showerhead 13. The second RF generating unit 31b is coupled to the conductive members of the substrate support 11 via at least one impedance matching circuit and is configured to generate a bias RF signal (bias RF power). In one embodiment, the bias RF signal has a frequency lower than that of the source RF signal. In one embodiment, the bias RF signal has a frequency in the range of 400 kHz to 13.56 MHz. In one embodiment, the second RF generator 31b may be configured to generate multiple bias RF signals having different frequencies. The generated bias RF signals are supplied to the conductive members of the substrate support 11. In various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0043] The power supply 30 may also include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a first DC generator 32a and a second DC generator 32b. In one embodiment, the first DC generator 32a is connected to a conductive member of the substrate support 11 and configured to generate a first DC signal. The generated first bias DC signal is applied to the conductive member of the substrate support 11. In one embodiment, the first DC signal may be applied to another electrode, such as an electrode in an electrostatic chuck. In one embodiment, the second DC generator 32b is connected to a conductive member of the showerhead 13 and configured to generate a second DC signal. The generated second DC signal is applied to the conductive member of the showerhead 13. In various embodiments, at least one of the first and second DC signals may be pulsed. The first and second DC generating units 32a and 32b may be provided in addition to the RF power supply 31, or the first DC generating unit 32a may be provided instead of the second RF generating unit 31b.

[0044] The exhaust system 40 may be connected to, for example, a gas exhaust port 10e provided at the bottom of the plasma processing chamber 10. The exhaust system 40 may include a pressure regulating valve and a vacuum pump. The pressure 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.

[0045] FIG. 3 is a partially enlarged view of a substrate processing apparatus according to an exemplary embodiment. As shown in FIG. 3, the substrate support 11 may include a temperature adjustment module 113 configured to adjust at least one of the main body 111, the ring assembly 112, and the substrate W to a target temperature. The temperature adjustment module 113 may include a heater, a heat transfer medium, a flow path, or a combination thereof. A heat transfer fluid such as brine or gas flows through the flow path. In one embodiment, the temperature adjustment module 113 includes a coolant flow path 113a formed inside the main body 111. A cooling medium, such as cooling water or brine, output from the chiller unit flows through the coolant inlet pipe 113b, the coolant flow path 113a, and the coolant outlet pipe 113c, returns to the chiller unit, and circulates through the above-mentioned path while being controlled to a predetermined temperature. This removes heat from the main body 111, cooling it.

[0046] 4 is a flowchart of a substrate processing method according to one exemplary embodiment. The substrate processing method shown in FIG. 4 (hereinafter referred to as "method MT1") can be performed by the substrate processing apparatus of the above-described embodiment. Method MT1 is applied to a substrate W. Method MT1 includes steps ST1, ST2, and ST3. Steps ST1, ST2, and ST3 are performed in sequence. Step ST2 may be performed simultaneously with step ST1.

[0047] Hereinafter, the method MT1 will be described using the case where the method MT1 is applied to a substrate W using the substrate processing apparatus of the above embodiment as an example. When the plasma processing apparatus 1 is used, the method MT1 can be executed in the plasma processing apparatus 1 by controlling each part of the plasma processing apparatus 1 by the control unit 2.

[0048] In the method MT1, a substrate W on a substrate support 11 disposed in a plasma processing chamber 10 is processed as shown in Figure 2. By the method MT1, the substrate W can be cleaned (or etched).

[0049] 5 is a partially enlarged cross-sectional view of an example substrate to which a substrate processing method according to an exemplary embodiment can be applied. As shown in FIG. 5, in one embodiment, the substrate W includes a base region UR, a metal-containing film MF, and a silicon-containing film SF. The silicon-containing film SF and the metal-containing film MF are provided on the base region UR and are located on the surface Wa of the substrate W.

[0050] The silicon-containing film SF may contain at least one of oxygen and nitrogen. The silicon-containing film SF may be a single-layer film or a multi-layer film. The silicon-containing film SF may be a silicon film, a silicon oxide film, or a silicon nitride film.

[0051] The silicon-containing film SF may have one or more recesses RS. The recesses RS may be openings. The recesses RS may be, for example, holes or trenches. The recesses RS may be formed by etching using the plasma processing apparatus 1. The metal-containing film MF may be exposed at the bottom of the recesses RS. The metal-containing film MF is not disposed below portions of the silicon-containing film SF between adjacent recesses RS.

[0052] A mask for forming the recesses RS by etching may be formed on the silicon-containing film SF. The mask contains, for example, carbon. For example, etching residues RD1 or RD2 generated when forming the recesses RS by etching may adhere to the surface Wa of the substrate W. The etching residue RD1 is a residue (reaction by-product) generated from the silicon-containing film SF. The etching residue RD2 is a residue (reaction by-product) generated from the metal-containing film MF.

[0053] In step ST1, a process gas containing hydrogen fluoride gas is supplied into the plasma processing chamber 10. The process gas may consist essentially of hydrogen fluoride gas alone, or may contain gases other than hydrogen fluoride gas. In one embodiment, the process gas contains hydrogen fluoride gas and an inert gas. Examples of the inert gas include a rare gas such as argon gas.

[0054] In step ST2, the temperature T of the substrate support 11 is controlled to a first temperature T1, and the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 is controlled to a first pressure P1. The control unit 2 is configured to perform such control.

[0055] FIG. 6 is a graph showing an example of an adsorption equilibrium pressure curve and saturated vapor pressure curve for hydrogen fluoride. The horizontal axis represents temperature (°C). The vertical axis represents pressure (mTorr). At the temperature and pressure on the adsorption equilibrium pressure curve C1 in the graph of FIG. 6, the adsorption and desorption of hydrogen fluoride are in equilibrium. The adsorption equilibrium pressure curve C1 may be depicted by an exponential function approximated using measurement data based on the BET adsorption theory.

[0056] The first temperature T1 and the first pressure P1 are located in a first region R1 above the adsorption equilibrium pressure curve C1 of hydrogen fluoride. As a result, in step ST2, hydrogen fluoride is adsorbed on the surface Wa of the substrate W. The first region R1 may be located below the saturated vapor pressure curve C2 of hydrogen fluoride. In this case, hydrogen fluoride is adsorbed in a gas phase on the surface Wa of the substrate W. When the first temperature T1 and the first pressure P1 are located above the saturated vapor pressure curve C2, hydrogen fluoride is adsorbed in a liquid phase on the surface Wa of the substrate W. The first temperature T1 may be in a range of -140°C or higher and 0°C or lower, or in a range of -70°C or higher and -30°C or lower. The first pressure P1 is 1 Pa or higher and 1×10 5 The pressure may be in the range of 100 Pa or less, or in the range of 30 Pa or more and 100 Pa or less. The time for step ST2 is not subject to time constraints as long as it is within a range in which a reaction product due to hydrogen fluoride adsorption is generated, and the cleaning amount is determined according to the time for step ST2. The temperature T of the substrate support 11 can be adjusted using the temperature control module 113. The temperature of the substrate W may be the same as the temperature T of the substrate support 11. The pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 can be adjusted by controlling the flow rate of the hydrogen fluoride gas with the flow rate controller 22. When the processing gas contains a gas other than hydrogen fluoride gas, the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 is the partial pressure of the hydrogen fluoride gas. Plasma is not generated in step ST2.

[0057] FIG. 7 is a partially enlarged cross-sectional view of an example substrate in which hydrogen fluoride is adsorbed on the surface of the substrate. As shown in FIG. 7, hydrogen fluoride is adsorbed on the surface Wa of the substrate W. Hydrogen fluoride molecules HF1 in the hydrogen fluoride gas can be adsorbed on the surface Wa of the substrate W. As a result, a layer HF2 containing hydrogen fluoride can be formed on the surface Wa of the substrate W. The layer HF2 is, for example, a hydrogen fluoride molecule layer. The layer HF2 is formed so as to cover the etching residue RD1 or RD2. The hydrogen fluoride in the layer HF2 may react with the etching residue RD1 or RD2 to form a reaction product HF3 (see FIG. 8), such as silicon fluoride.

[0058] Before step ST1, a process gas containing an inert gas but not containing hydrogen fluoride gas may be supplied into the plasma processing chamber 10. In this case, the temperature T of the substrate support 11 may be controlled to a first temperature T1, and the pressure of the inert gas in the plasma processing chamber 10 may be controlled to a first pressure P1. Thereafter, the process gas containing the inert gas may be replaced with a process gas containing hydrogen fluoride gas, thereby simultaneously starting steps ST1 and ST2.

[0059] In step ST3, the temperature T of the substrate support 11 is controlled to a second temperature T2, and the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 is controlled to a second pressure P2. The control unit 2 is configured to perform such control. In the graph of FIG. 6, the second temperature T2 and the second pressure P2 are located in a second region R2 below the adsorption equilibrium pressure curve C1. As a result, in step ST3, the hydrogen fluoride adsorbed on the surface Wa of the substrate W is desorbed. The second temperature T2 may be in the range of -140°C or higher and 0°C or lower, or may be in the range of -70°C or higher and -30°C or lower. The second pressure P2 is 1 Pa or higher and 1×10 5The pressure may be in the range of 100 Pa or less, or in the range of 30 Pa or more and 100 Pa or less. There are no time restrictions on the duration of step ST3 as long as the reaction product of hydrogen fluoride adsorption can be desorbed. The second temperature T2 may be higher than the first temperature T1. The second pressure P2 may be lower than the first pressure P1. Step ST3 may be performed after stopping the supply of the process gas containing hydrogen fluoride gas in order to promote the desorption of hydrogen fluoride. No plasma is generated in step ST3.

[0060] 8 is a partially enlarged cross-sectional view of an example substrate when adsorbed hydrogen fluoride is desorbed. In step ST3, the hydrogen fluoride adsorbed on the surface Wa of the substrate W is desorbed. The hydrogen fluoride molecules adsorbed on the surface Wa of the substrate W are desorbed and become hydrogen fluoride gas. As the hydrogen fluoride is desorbed, the etching residue RD1 or RD2 may be separated from the surface Wa of the substrate W. Alternatively, as shown in FIG. 8, the reaction product HF3 generated in step ST2 is desorbed from the surface Wa of the substrate W. In this way, the etching residue RD1 or RD2 can be removed from the surface Wa of the substrate W in step ST3.

[0061] According to the method MT1, when substances such as etching residues RD1 and RD2 are present on the surface Wa of the substrate W, the substances can be removed together with the desorption of hydrogen fluoride.

[0062] If the substrate W has a silicon-containing film SF, substances generated from the silicon-containing film SF can be removed along with the desorption of hydrogen fluoride.If the substrate W has a metal-containing film MF, substances generated from the metal-containing film MF can be removed along with the desorption of hydrogen fluoride.

[0063] When the processing gas contains an inert gas, the amount of material removed can be adjusted by adjusting the flow rate of the inert gas. For example, increasing the flow rate of the inert gas decreases the flow rate of the hydrogen fluoride gas, thereby decreasing the amount of material removed.

[0064] Before step ST1, the substrate W may be etched using plasma generated in the plasma processing chamber 10. For example, after forming the recess RS by etching, steps ST1, ST2, and ST3 may be performed. This allows etching and cleaning to be performed successively in situ without removing the substrate W from the plasma processing chamber 10.

[0065] 9 is a plan view of an example substrate having a surface to which a substance generated by a substrate processing apparatus is attached. In step ST2, as shown in FIG. 9, a substance generated by the substrate processing apparatus of the above embodiment may be attached to the surface Wa of the substrate W. The substance may be silicon-containing particles PT1 generated by the plasma processing apparatus 1, or metal-containing particles PT2 generated by the plasma processing apparatus 1. The silicon-containing particles PT1 contain, for example, silicon oxide. The metal-containing particles PT2 contain, for example, yttrium or aluminum. The metal-containing particles PT2 contain, for example, yttrium oxide or aluminum oxide.

[0066] When the method MT1 is applied to the substrate W of FIG. 9, substances such as silicon-containing particles PT1 or metal-containing particles PT2 can be removed.

[0067] FIG. 10 is a flowchart of a component processing method according to one exemplary embodiment. The component processing method shown in FIG. 10 (hereinafter referred to as "method MT2") can be performed by the substrate processing apparatus of the above-described embodiment. Method MT2 is applied to the plasma processing apparatus 1. When method MT2 is performed, the substrate W does not need to be present in the plasma processing chamber 10. Method MT2 includes steps ST11, ST12, and ST13. Steps ST11, ST12, and ST13 are performed in sequence. Step ST12 may be performed simultaneously with step ST11.

[0068] Hereinafter, the method MT2 will be described taking as an example a case where the method MT2 is applied to the ring assembly 112 (see FIG. 3) using the substrate processing apparatus of the above embodiment. When the plasma processing apparatus 1 is used, the method MT2 can be performed in the plasma processing apparatus 1 by controlling each part of the plasma processing apparatus 1 by the control unit 2.

[0069] Method MT2 processes ring assembly 112 as a component disposed in plasma processing chamber 10. Surface 112a of ring assembly 112 may have substances attached thereto, such as silicon-containing particles PT1 or metal-containing particles PT2 shown in Figure 9. Method MT2 allows ring assembly 112 to be cleaned (or etched).

[0070] In step ST11, a processing gas containing hydrogen fluoride gas is supplied into the plasma processing chamber 10. Step ST11 can be performed in the same manner as step ST1, except that the substrate W is not placed on the substrate support 11.

[0071] In step ST12, the temperature TR of the ring assembly 112 is controlled to a first temperature T1, and the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 is controlled to a first pressure P1. This causes hydrogen fluoride to be adsorbed on the surface 112a of the ring assembly 112. Step ST12 can be performed in the same manner as step ST2, except that the substrate W is not placed on the substrate support 11. The temperature TR of the ring assembly 112 may be the same as the temperature T of the substrate support 11, and can be adjusted using the temperature adjustment module 113. The temperature TR of the ring assembly 112 may also be adjusted using a temperature adjustment module different from the temperature adjustment module 113.

[0072] In step ST13, the temperature TR of the ring assembly 112 is controlled to a second temperature T2, and the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 is controlled to a second pressure P2. This causes the hydrogen fluoride adsorbed on the surface 112a of the ring assembly 112 to desorb. Step ST13 can be performed in the same manner as step ST3, except that the substrate W is not placed on the substrate support 11.

[0073] According to the method MT2, if substances such as silicon-containing particles PT1 or metal-containing particles PT2 are present on the surface 112a of the ring assembly 112, the substances can be removed while desorbing hydrogen fluoride.

[0074] The following description will be given taking as an example a case where the method MT1 is applied to a substrate W1 using the substrate processing apparatus of the above embodiment. In this case, when performing the method MT1, a substrate W1 is used instead of the above-described substrate W. The method MT1 can clean (or etch) the substrate W1.

[0075] FIG. 11 is a partially enlarged cross-sectional view of an example substrate to which a substrate processing method according to an illustrative embodiment can be applied. As shown in FIG. 11 , in one embodiment, the substrate W1 includes a carbon-containing film AC and a mask MS disposed on the carbon-containing film AC. The carbon-containing film AC may have one or more recesses RS. The carbon-containing film AC may be an amorphous carbon film. The mask MS may be a mask for forming the recesses RS by etching. The mask MS may have an opening MSa located over the recesses RS. The mask MS may be a film containing silicon, oxygen, and nitrogen. A deposit DP, for example, generated when forming the recesses RS by etching, may adhere to the opening MSa of the mask MS. The deposit DP may contain silicon and oxygen. The deposit DP may reduce the dimension CD of the opening MSa of the mask MS.

[0076] 12 is a partially enlarged cross-sectional view of an example substrate in which hydrogen fluoride is adsorbed on the surface of the substrate. In step ST2, as shown in FIG. 12, hydrogen fluoride is adsorbed on the surface W1a of the substrate W1. Hydrogen fluoride molecules HF1 in the hydrogen fluoride gas can be adsorbed to the openings MSa in the mask MS. This can result in the formation of an adsorption layer containing hydrogen fluoride on the surface W1a of the substrate W1. The adsorption layer is formed to cover the deposits DP. The hydrogen fluoride in the adsorption layer may react with the deposits DP to form a reaction product HF3 (see FIG. 13), such as silicon fluoride.

[0077] 13 is a partially enlarged cross-sectional view of an example substrate in which adsorbed hydrogen fluoride is desorbed. In step ST3, the hydrogen fluoride adsorbed on the surface W1a of the substrate W1 is desorbed. The hydrogen fluoride molecules adsorbed on the surface W1a of the substrate W1 are desorbed and become hydrogen fluoride gas. As the hydrogen fluoride is desorbed, the deposit DP may be separated from the surface Wa of the substrate W. Alternatively, as shown in FIG. 13, the reaction product HF3 generated in step ST2 is desorbed from the opening MSa of the mask MS. In this way, the deposit DP can be removed from the surface W1a of the substrate W1 in step ST3.

[0078] According to the method MT1, when a substance such as a deposit DP is present in the opening MSa of the mask MS, the substance can be removed along with the desorption of hydrogen fluoride. According to the method TM1, compared to removing the substance by plasma etching, it is possible to increase the dimension CD of the opening MSa of the mask MS while suppressing a decrease in the thickness TH of the mask MS.

[0079] Various experiments performed to evaluate Method MT1 are described below, but the experiments described below are not intended to limit the present disclosure.

[0080] (First experiment) In the first experiment, a substrate W was prepared, which included a silicon oxide film and a mask on the silicon oxide film. The silicon oxide film was etched using the mask to form recesses RS. The method MT1 was then performed on the substrate W using the plasma processing system. In step ST2, the first temperature T1 was −70° C., and the first pressure P1 was 50 Pa. In step ST3, the second temperature T2 was −70° C., and the second pressure P2 was 2 Pa.

[0081] Figures 14(a) and 14(b) are partially enlarged plan views of the surface of an example substrate. Figure 14(a) shows the surface Wa of the substrate W before the above-mentioned method MT1 is performed. Figure 14(b) shows the surface Wa of the substrate W after the above-mentioned method MT1 is performed. In Figure 14(a), etching residues RD1 are attached to the surface Wa of the substrate W. On the other hand, in Figure 14(b), the etching residues RD1 have been removed from the surface Wa of the substrate W. In this way, an effect equivalent to that obtained when using a hydrogen fluoride solution was obtained.

[0082] (Second experiment) In the second experiment, a substrate W having a silicon oxide film was prepared. The temperature T of the substrate support 11 was fixed at -70°C, and the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 was changed, and the above-mentioned method MT1 was performed on the substrate W. The etching amount (film thickness reduction) of the silicon oxide film was then measured. The larger the etching amount, the higher the cleaning effect. The results are shown in Figure 15. Furthermore, the pressure P of the hydrogen fluoride gas in the plasma processing chamber 10 was fixed at 350 mTorr (1 mTorr = 0.133322 Pa), and the temperature T of the substrate support 11 was changed, and the above-mentioned method MT1 was then performed on the substrate W. The etching amount of the silicon oxide film was then measured. The results are shown in Figure 16.

[0083] Figure 15 is a graph showing an example of the relationship between the pressure of hydrogen fluoride gas and the etching amount. The vertical axis represents the etching amount (nm). The horizontal axis represents the hydrogen fluoride gas pressure P (mTorr). Two experiments were conducted for each pressure P. E1 and E2 represent the results of the two experiments. Figure 15 shows that the etching amount increases as the pressure P increases. Therefore, the etching amount can be controlled by adjusting the pressure P. Furthermore, it was found that the etching amount can be more easily controlled in the low-pressure region below 200 mTorr. It was also found that the increasing profile of pressure P approximates the Langmuir adsorption line. This suggests that the adsorption and desorption of hydrogen fluoride gas molecules may be dominant.

[0084] FIG. 16 is a graph showing an example of the relationship between the temperature of the substrate support and the etching amount. The vertical axis represents the etching amount (nm). The horizontal axis represents the temperature T (°C) of the substrate support 11. Two experiments were conducted for each temperature T. E3 and E4 show the results of the two experiments. From FIG. 16, it can be seen that the etching amount decreases as the temperature T increases. When the temperature T is -35°C, the etching amount decreases compared to when it is -70°C.

[0085] (Third experiment) In the third experiment, a substrate W1 (see FIG. 11) was prepared, which included an amorphous carbon film and a mask on the amorphous carbon film. The mask was a SiON film. The amorphous carbon film was etched using the mask to form recesses RS. Then, using the plasma processing system described above, the method MT1 was performed on the substrate W1, varying the time (adsorption time) in step ST2. The first temperature T1 and first pressure P1 in step ST2 were located in a first region R1 above the adsorption equilibrium pressure curve C1 of hydrogen fluoride. The thickness of the mask and the dimensions of the opening in the mask were then measured. The results are shown in FIG. 17.

[0086] FIG. 17 is a graph showing an example of the relationship between adsorption time and the thickness of the mask or the size of the opening in the mask. The vertical axis shows the thickness of the mask or the size of the opening in the mask (nm). The horizontal axis shows the adsorption time (seconds). The result for an adsorption time of zero shows the thickness or size of the substrate W1 before method MT1 was performed. From FIG. 17, it can be seen that when the adsorption time is about 60 seconds, the size of the opening in the mask can be increased while suppressing a decrease in the thickness of the mask.

[0087] (Experiment 4) In the fourth experiment, the same substrate W1 as in the third experiment was prepared, and the amorphous carbon film was etched using a mask to form recesses RS. Then, using the plasma processing system described above, the method MT1 was performed on the substrate W1 while varying the first temperature T1 in step ST2. The first temperature T1 and first pressure P1 in step ST2 were located in the first region R1 above the hydrogen fluoride adsorption equilibrium pressure curve C1. The thickness of the mask and the dimensions of the mask opening were then measured, and the rate of decrease in the mask thickness and the rate of increase in the dimensions of the mask opening were calculated. The results are shown in Figure 18.

[0088] FIG. 18 is a graph showing an example of the relationship between temperature and the rate of decrease in mask thickness or the rate of increase in the size of the mask opening. The vertical axis represents the rate of decrease in mask thickness or the rate of increase in mask opening size (nm / min). The horizontal axis represents temperature (°C). FIG. 18 shows that the lower the temperature, the more the size of the mask opening can be increased while suppressing the decrease in mask thickness.

[0089] (5th experiment) In the fifth experiment, the same substrate W1 as in the third experiment was prepared, and the amorphous carbon film was etched using a mask to form recesses RS. Then, using the plasma processing system described above, the method MT1 was performed on the substrate W1 while varying the first pressure P1 in step ST2. The first temperature T1 and first pressure P1 in step ST2 were located in the first region R1 above the hydrogen fluoride adsorption equilibrium pressure curve C1. The thickness of the mask and the dimensions of the mask opening were then measured, and the rate of decrease in the mask thickness and the rate of increase in the dimensions of the mask opening were calculated. The results are shown in Figure 19.

[0090] FIG. 19 is a graph showing an example of the relationship between pressure and the rate of mask thickness reduction or mask opening size increase. The vertical axis represents the rate of mask thickness reduction or mask opening size increase (nm / min). The horizontal axis represents pressure (mTorr). FIG. 19 shows that the higher the pressure, the more the mask opening size can be increased while suppressing mask thickness reduction.

[0091] FIG. 20 is a flowchart of a substrate processing method according to an exemplary embodiment. The substrate processing method shown in FIG. 20 (hereinafter referred to as "method MT3") can be performed by the substrate processing apparatus according to the above-described embodiment. When the plasma processing apparatus 1 is used, the method MT3 can be performed in the plasma processing apparatus 1 by controlling each unit of the plasma processing apparatus 1 using the control unit 2. The method MT3 includes steps ST21, ST22, ST23, ST24, and ST25. Steps ST21 to ST25 can be performed sequentially. Steps ST21 to ST25 can be performed in situ or in different chambers. For example, steps ST21, ST22, and ST24 can be performed in the plasma processing chamber 10, while steps ST23 and ST25 can be performed in a chamber different from the plasma processing chamber 10. Steps ST23 and ST25 can be performed by batch processing or single-wafer processing. At least one of steps ST24 and ST25 can be omitted.

[0092] 11 to 13 and 20, an example in which the method MT3 is applied to the substrate W1 using the substrate processing apparatus of the above embodiment will be described below. The substrate W1 can be cleaned (or etched) by the method MT3.

[0093] In step ST21, a substrate W1 is provided. The substrate W1 includes a carbon-containing film AC as an underlayer film and a mask MS having an opening MSa disposed on the carbon-containing film AC. The substrate W1 may be placed on a substrate support 11 disposed in a plasma processing chamber 10, as shown in FIG.

[0094] The mask MS may contain silicon. The mask MS may be a silicon-containing film. The silicon-containing film may include at least one of a silicon film, a silicon nitride film, a silicon carbide film, and a silicon oxynitride film. The silicon-containing film does not have to include a silicon oxide film.

[0095] The carbon-containing film AC may be any film containing carbon, and may include, for example, at least one of a spin-on carbon (SOC) film, an amorphous carbon film, and a resist film. The resist film may be an ArF resist film, a KrF resist film, or the like. A film different from the carbon-containing film AC may be used as the underlayer film. As the underlayer film different from the carbon-containing film AC, for example, at least one of a polycrystalline silicon film, an amorphous silicon film, and a SiGe film may be used.

[0096] 11, in step ST22, the carbon-containing film AC is etched using plasma. The plasma may be generated from a first process gas supplied into the plasma processing chamber 10. By the etching, recesses RS are formed in the carbon-containing film AC, and deposits DP are attached to the openings MSa of the mask MS.

[0097] In step ST23, as shown in FIGS. 12 and 13, hydrogen fluoride is supplied to the mask MS to remove the deposits DP. In one exemplary embodiment, a second process gas containing hydrogen fluoride gas is supplied into the plasma processing chamber 10. In step ST23, steps ST1 to ST3 of the method MT1 described above can be performed. Hydrogen fluoride molecules HF1 in the hydrogen fluoride gas react with the deposits DP to generate reaction products HF3 such as silicon fluoride. The reaction products HF3 volatilize, removing the deposits DP. In one exemplary embodiment, the second process gas containing hydrogen fluoride gas is supplied without generating plasma. In this case, etching of the mask MS by the plasma can be suppressed. As a result, deformation of the mask MS can be suppressed.

[0098] In step ST24, similarly to step ST22, the carbon-containing film AC is etched using plasma.

[0099] In step ST25, similar to step ST23, hydrogen fluoride is supplied to the mask MS so as to remove the deposit DP formed in step ST24.

[0100] After step ST25, steps ST22 and ST23 may be further repeated, thereby deepening the recesses RS.

[0101] According to the method MT3, the deposits DP can be removed by hydrogen fluoride in step ST23 while suppressing deformation of the mask MS. Therefore, in step ST24, recesses RS having a desired shape can be formed in the carbon-containing film AC. For example, compared to removing the deposits DP using plasma generated from a fluorine-containing gas other than hydrogen fluoride, poor shape (bowing) of the recesses RS can be suppressed. This is thought to be because step ST24 can be performed with the slope of the shoulders of the mask MS small.

[0102] In one example, the recess RS having the desired shape has sidewalls parallel to the thickness direction of the carbon-containing film AC. In another example, the recess RS having the desired shape has sidewalls inclined with respect to the thickness direction of the carbon-containing film AC. For example, the sidewalls of the recess RS have a tapered shape.

[0103] 21 is a schematic diagram illustrating a substrate processing apparatus according to an exemplary embodiment, in which the method MT3 may be applied to the substrate W1 using the substrate processing apparatus illustrated in FIG.

[0104] 21 includes a plasma processing apparatus 1, a controller 2, and a wet processing apparatus 200. The substrate processing apparatus may include a transfer robot that transfers the substrate W1 between the plasma processing apparatus 1 and the wet processing apparatus 200. The controller 2 is configured to control each component of the plasma processing apparatus 1 and the wet processing apparatus 200. Under the control of the controller 2, a method MT3 can be performed in the substrate processing apparatus of FIG.

[0105] The wet processing apparatus 200 may include a container 210 for containing hydrofluoric acid, a container 212 for containing a rinse liquid, and a container 214 for containing pure water. The wet processing apparatus 200 may also include a dryer for drying the substrate W1.

[0106] The wet processing apparatus 200 may include an inlet 216 for receiving the substrate W1 unloaded from the plasma processing apparatus 1, an outlet 218 for unloading the substrate W1 into the plasma processing apparatus 1, and a transfer robot 220 for transporting the substrate W1. The transfer robot 220 transports the substrate W1 from the inlet 216 to the container 210. The transfer robot 220 transports the substrate W1 from the container 210 to the container 212. The transfer robot 220 transports the substrate W1 from the container 212 to the container 214. The transfer robot 220 transports the substrate W1 from the container 214 to the outlet 218.

[0107] When the method MT3 is performed in the substrate processing apparatus of FIG. 21 , steps ST21, ST22, and ST24 may be performed in the plasma processing apparatus 1. Steps ST23 and ST25 may be performed in the wet processing apparatus 200. In steps ST23 and ST25, hydrofluoric acid is supplied to the substrate W1. As a result, the deposits DP are removed by the hydrofluoric acid. The substrate W1 may be immersed in hydrofluoric acid in the container 210. Thereafter, the substrate W1 may be immersed in a rinse liquid in the container 212. Thereafter, the substrate W1 may be immersed in pure water in the container 214. Thereafter, the substrate W1 may be dried in a dryer of the wet processing apparatus 200. Alternatively, the substrate W1 may be dried by reducing the pressure in the plasma processing chamber 10 of the plasma processing apparatus 1.

[0108] Various experiments performed to evaluate method MT3 are described below, but the experiments described below are not intended to limit the present disclosure.

[0109] (Experiment 6) In the sixth experiment, a substrate was prepared that included an amorphous carbon film and a mask disposed on the amorphous carbon film. The mask was a silicon oxynitride film. Then, steps ST21 to ST23 of the method MT3 were performed on the substrate. In step ST22, the amorphous carbon film was etched using plasma. In step ST23, the substrate was immersed in hydrofluoric acid. This removed deposits that had adhered to the openings of the mask due to etching.

[0110] (Experiment 7) In the seventh experiment, after step ST22, step ST23 was not performed, and deposits adhering to the openings of the mask were removed using plasma generated from a fluorine-containing gas other than hydrogen fluoride.

[0111] (result) The depth and dimensions of the recesses formed in the amorphous carbon film were measured from the cross-sectional images of the substrates obtained in Experiments 6 and 7. The results are shown in FIG.

[0112] FIG. 22 is a graph showing an example of the relationship between recess depth and recess dimension. The vertical axis represents the depth (μm) of the recess formed in the amorphous carbon film. The position where the vertical axis value is 0 μm is the boundary position between the amorphous carbon film and the mask. The horizontal axis represents the dimension (nm) of the recess formed in the amorphous carbon film. In the graph, E6 represents the results of the sixth experiment, and E7 represents the results of the seventh experiment. As shown in FIG. 22, in the depth ranges of −0.5 to 0 μm and −3 to −1 μm, the recess dimension in the sixth experiment was smaller than the recess dimension in the seventh experiment. This indicates that the sixth experiment suppressed recess shape defects (bowing) compared to the seventh experiment.

[0113] Furthermore, the positions of the mask openings were measured from the cross-sectional images of the substrate obtained in Experiments 6 and 7. The results are shown in FIG.

[0114] FIG. 23 is a graph showing an example of the position of the mask opening. The vertical axis represents the position (μm) in the thickness direction of the mask. The position where the vertical axis value is 0 μm is the boundary position between the amorphous carbon film and the mask. The horizontal axis represents the position (nm) in the surface direction of the substrate (the direction perpendicular to the thickness direction of the mask). The position where the horizontal axis value is 0 μm is the center position of the mask opening. In the graph, E8 represents the results of the sixth experiment, and E9 represents the results of the seventh experiment. As shown in FIG. 23, the mask thickness in the sixth experiment was greater than that in the seventh experiment. This indicates that mask etching was suppressed in the sixth experiment compared to the seventh experiment. Also, as shown in FIG. 23, the inclination E8a of the mask shoulder with respect to the surface direction of the substrate W1 in the sixth experiment was smaller than the inclination E9a of the mask shoulder with respect to the surface direction of the substrate W1 in the seventh experiment. This indicates that the mask shoulder was less likely to deform in the sixth experiment compared to the seventh experiment.

[0115] FIG. 24 is a partially enlarged cross-sectional view of an example substrate. As shown in FIG. 24, in the cross section of the substrate W1, the shoulder of the mask MS is inclined at an angle θ with respect to the surface direction of the substrate W1. If the angle θ is small, ions I1 in the plasma collide with the shoulder of the mask and sputter the mask. On the other hand, if the angle θ is large, ions I2 in the plasma may be reflected by the shoulder of the mask into the recess RS. As a result, the sidewall of the recess RS is etched by the ions I2, which is likely to cause a defective shape of the recess (bowing).

[0116] Although various exemplary embodiments have been described above, the present invention is not limited to the above-described exemplary embodiments, and various additions, omissions, substitutions, and modifications may be made. Furthermore, elements in different embodiments may be combined to form other embodiments.

[0117] For example, the substrate processing apparatus does not have to include the plasma generating unit 12. In this case, plasma processing is not performed in the chamber of the substrate processing apparatus. Methods MT1 and MT2 can also be performed using such a substrate processing apparatus.

[0118] From the foregoing, it will be understood that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the appended claims. [Explanation of symbols]

[0119] 2...controller, 10...plasma processing chamber, 11...substrate support, 20...gas supply, 112...ring assembly, 112a...surface, C1...adsorption equilibrium pressure curve, R1...first region, R2...second region, W, W1...substrate.

Claims

1. A chamber, a substrate support within the chamber; a temperature regulation module configured to regulate a temperature of at least one of the substrate support and the substrate; a gas supply configured to supply a process gas containing hydrogen fluoride gas into the chamber; an exhaust system configured to regulate the pressure within the chamber; A control unit; Equipped with The control unit (a) placing the substrate on the substrate support; (b) supplying the process gas into the chamber; (c) controlling the temperature of the substrate support to a first temperature and the pressure of the hydrogen fluoride gas in the chamber to a first pressure; (d) controlling the temperature of the substrate support to a second temperature and the pressure of the hydrogen fluoride gas in the chamber to a second pressure; configured to perform a process including At least one of the temperature control module, the gas supply unit, and the exhaust system is controlled so that the second temperature is higher than the first temperature and / or the second pressure is lower than the first pressure; a substrate processing apparatus, wherein control is performed so that, in a graph having temperature on the horizontal axis and pressure on the vertical axis, the first temperature and the first pressure are located in a first region above an adsorption equilibrium pressure curve of hydrogen fluoride, and the second temperature and the second pressure are located in a second region below the adsorption equilibrium pressure curve.

2. The substrate processing apparatus according to claim 1 , wherein control is performed so that the first region is located below a saturated vapor pressure curve of hydrogen fluoride in the graph.

3. A chamber, a substrate support within the chamber; a temperature regulation module configured to regulate a temperature of at least one of the substrate support and the substrate; a gas supply configured to supply a process gas containing hydrogen fluoride gas into the chamber; an exhaust system configured to regulate the pressure within the chamber; A control unit; Equipped with The control unit (a) placing the substrate on the substrate support; (b) supplying the process gas into the chamber; (c) controlling the temperature of the substrate support to a first temperature and the pressure of the hydrogen fluoride gas in the chamber to a first pressure; (d) controlling the temperature of the substrate support to a second temperature and the pressure of the hydrogen fluoride gas in the chamber to a second pressure; configured to perform a process including At least one of the temperature control module, the gas supply unit, and the exhaust system is controlled so that the second temperature is higher than the first temperature and / or the second pressure is lower than the first pressure; The first temperature and the second temperature are in the range of −140° C. or more and 0° C. or less, and the first pressure and the second pressure are in the range of 1 Pa or more and 1×10 ５ The substrate processing apparatus is controlled so that the temperature is within a range of Pa or less.

4. A substrate processing apparatus as described in claim 3, in which control is performed so that, in a graph with temperature on the horizontal axis and pressure on the vertical axis, the first temperature and the first pressure are located in a first region above the adsorption equilibrium pressure curve of hydrogen fluoride, and the second temperature and the second pressure are located in a second region below the adsorption equilibrium pressure curve.

5. A substrate processing apparatus as described in claim 4, wherein control is performed so that the first region in the graph is located below the saturated vapor pressure curve of hydrogen fluoride.

6. 6. The substrate processing apparatus according to claim 1, wherein the temperature adjustment module includes a heater, a heat transfer medium, a flow path, or a combination thereof.

7. The substrate processing apparatus according to claim 1, wherein the substrate comprises a silicon-containing film.

8. The substrate processing apparatus according to claim 1, wherein the substrate comprises a metal-containing film.

9. 9. The substrate processing apparatus according to claim 1, wherein in (c), a substance produced in the substrate processing apparatus adheres to the surface of the substrate.

10. 10. The substrate processing apparatus according to claim 1, wherein the processing gas includes an inert gas.

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