Plasma treatment method, plasma treatment apparatus, and plasma treatment system

Abstract

This invention provides a plasma processing method that allows for controllable aperture dimensions. [Solution] The plasma processing method according to the present disclosure includes a preparation step of preparing a substrate having (a) a film to be etched, (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface that defines at least one opening on the upper surface of the film to be etched, and (c) a first film comprising at least a first portion and a second portion, wherein the first portion is a portion formed on the upper surface of the photoresist film and the second portion is a portion formed on the side surface of the photoresist film, and the first portion is thicker than the second portion, and a trimming step of etching at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a plasma processing method, a plasma processing apparatus, and a plasma processing system.

Background Art

[0002] As a technique for improving the controllability of patterns, there are a method and an apparatus for processing a substrate described in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a plasma processing method, a plasma processing apparatus, and a plasma processing system capable of controlling the dimensions of openings.

Means for Solving the Problems

[0005] In one exemplary embodiment of the present disclosure, a plasma processing method is provided. The plasma processing method includes a preparation step of preparing a substrate having (a) an etching target film, (b) a photoresist film formed on the upper surface of the etching target film and having a side surface that defines at least one opening on the upper surface of the etching target film, and (c) a first film including at least a first portion and a second portion, wherein the first portion is formed on the upper surface of the photoresist film, the second portion is formed on the side surface of the photoresist film, and the first portion is thicker than the second portion, and a trimming step of etching at least a part of the side surface of the photoresist film and at least a part of the second portion of the first film.

[0006] In one exemplary embodiment of the present disclosure, a plasma processing apparatus is provided. The plasma processing apparatus comprises a plasma processing chamber, a gas supply unit for supplying a processing gas to the plasma processing chamber, a power supply unit for supplying power for generating plasma in the plasma processing chamber, and a control unit, wherein the control unit places a substrate having (a) a film to be etched, (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface defining at least one opening on the upper surface of the film to be etched, (c) a first film comprising at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, wherein the first portion is thicker than the second portion, and (d) a second film formed on at least the first portion of the first film, and performs control to etch at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film.

[0007] In one exemplary embodiment of the present disclosure, a plasma processing system is provided. The plasma processing system comprises a first plasma processing apparatus having a first chamber and a second plasma processing apparatus having a second chamber, wherein the first plasma processing apparatus is configured to place a substrate in the first chamber having (a) a film to be etched and (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface defining at least one opening on the upper surface of the film to be etched, and to form a first film in the first chamber having (c) a first film including at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, wherein the first portion is thicker than the second portion, and (d) to form a second film on at least the first portion of the first film, and the second plasma processing apparatus is configured to etch at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film.

[0008] In one exemplary embodiment of the present disclosure, a plasma processing method is provided. The plasma processing method includes the steps of: preparing (a) a film to be etched and (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface defining at least one opening on the upper surface of the film to be etched; determining the ratio of the film thickness of the photoresist film to the dimensions of the opening; forming a first film on the photoresist film if the ratio is 1 or more and less than 2; forming a first film on the photoresist film and a second film on the first film if the ratio is less than 1; and trimming the photoresist film by etching at least a portion of the side surface of the photoresist film, wherein the first film includes at least (c) a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, the first portion being thicker than the second portion, and the second film is (d) formed on at least the first portion of the first film. [Effects of the Invention]

[0009] According to one exemplary embodiment of the present disclosure, a plasma processing method, a plasma processing apparatus, and a plasma processing system can be provided that allow control over the dimensions of an aperture. [Brief explanation of the drawing]

[0010] [Figure 1] This figure schematically shows a plasma processing apparatus 1 according to one exemplary embodiment. [Figure 2] This figure schematically shows a substrate processing system PS according to one exemplary embodiment. [Figure 3] This flowchart shows an example of this processing method. [Figure 4A] This figure shows an example of a substrate W. [Figure 4B] This figure shows an example of a substrate W. [Figure 5A] This diagram schematically shows an example of the cross-sectional structure of the substrate W, following the flow of this processing method. [Figure 5B] It is a diagram schematically showing an example of the cross-sectional structure of the substrate W along the flow of this processing method. [Figure 5C] It is a diagram schematically showing an example of the cross-sectional structure of the substrate W along the flow of this processing method. [Figure 5D] It is a diagram schematically showing an example of the cross-sectional structure of the substrate W along the flow of this processing method. [Figure 5E] It is a diagram schematically showing an example of the cross-sectional structure of the substrate W along the flow of this processing method. [Figure 6] It is a flowchart showing a modification example of this processing method. [Figure 7] It is a flowchart showing a modification example of this processing method. [Figure 8] It is a flowchart showing a modification example of this processing method. [Figure 9] It is a flowchart showing a modification example of this processing method.

Mode for Carrying Out the Invention

[0011] Hereinafter, each embodiment of the present disclosure will be described.

[0012] In one exemplary embodiment, a plasma processing method is provided. The plasma processing method includes a preparation step of preparing a substrate having (a) an etching target film, (b) a photoresist film formed on the upper surface of the etching target film and having a side surface defining at least one opening on the upper surface of the etching target film, and (c) a first film including at least a first portion and a second portion, wherein the first portion is a portion formed on the upper surface of the photoresist film, the second portion is a portion formed on the side surface of the photoresist film, and the thickness of the first portion is thicker than that of the second portion; and a trimming step of etching at least a part of the side surface of the photoresist film and at least a part of the second portion of the first film.

[0013] In one exemplary embodiment, the preparation step includes a step of forming a second film on at least the first portion of the first film.

[0014] In one exemplary embodiment, after the trimming process, an etching process is further included in which the etched film is etched using the photoresist film, the first film, and the second film as masks.

[0015] In one exemplary embodiment, the side surface of the photoresist film has at least one of a recessed portion and a portion protruding from the side surface to the opening.

[0016] In one exemplary embodiment, the protruding portion exists from the side surface of the photoresist film to the upper surface of the etched film.

[0017] In one exemplary embodiment, the first film is an organic film and the second film is an inorganic film.

[0018] <​​​​​​​​​​​​​​​​​​​​​​​​In one exemplary embodiment, the predetermined processing gas includes an oxygen-containing gas and a halogen-containing gas.

[0025] In one exemplary embodiment, the first and second films are formed by plasma CVD.

[0026] In one exemplary embodiment, a first film is formed using plasma generated from a gas containing a carbon-containing gas, and a second film is formed using plasma generated from a gas containing a Si-containing gas.

[0027] In one exemplary embodiment, the carbon-containing gas is CxHy (where x and y are integers greater than or equal to 1), CtHuFv (where t and v are integers greater than or equal to 1, and u is an integer greater than or equal to 0), CO, or CO2.

[0028] In one exemplary embodiment, the thickness of the first portion of the first film is greater than the thickness of the photoresist film and the thickness of the second film.

[0029] In one exemplary embodiment, the etching step etches the film to be etched and the second film.

[0030] In one exemplary embodiment, the film to be etched is a Si-containing film, and the second film is a Si-containing film.

[0031] In one exemplary embodiment, the trimming and etching processes are performed within the same chamber.

[0032] In one exemplary embodiment, the trimming step further includes measuring the dimensions of an opening defined on the etched film by the etched side in the trimming step, forming a third film on the etched side in the trimming step based on the measured dimensions, and etching a portion of the third film.

[0033] In one exemplary embodiment, the third film includes an organic film.

[0034] In one exemplary embodiment, the third film is a laminated film comprising an organic film and an inorganic film formed on the organic film.

[0035] In one exemplary embodiment, the trimming step includes repeating the steps of measuring the dimensions of the opening, forming a third film, and etching a portion of the third film.

[0036] In one exemplary embodiment, a plasma processing apparatus is provided. The plasma processing apparatus comprises a plasma processing chamber, a gas supply unit for supplying a processing gas to the plasma processing chamber, a power supply unit for supplying power for generating plasma in the plasma processing chamber, and a control unit, the control unit placing a substrate having (a) a film to be etched, (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface defining at least one opening on the upper surface of the film to be etched, (c) a first film comprising at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, wherein the first portion is thicker than the second portion, and (d) a second film formed on at least the first portion of the first film, and performing control to etch at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film.

[0037] In one exemplary embodiment, a plasma processing system is provided. The plasma processing system comprises a first plasma processing apparatus having a first chamber and a second plasma processing apparatus having a second chamber, wherein the first plasma processing apparatus is configured to place a substrate in the first chamber having (a) a film to be etched and (b) a photoresist film formed on the upper surface of the film to be etched and having sides defining at least one opening on the upper surface of the film to be etched, and to form a first film in the first chamber, (c) a first film including at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side of the photoresist film, wherein the first portion is thicker than the second portion, and (d) a second film formed on at least the first portion of the first film, and the second plasma processing apparatus is configured to etch at least a portion of the side of the photoresist film and at least a portion of the second portion of the first film.

[0038] In one exemplary embodiment, a plasma processing method is provided. The plasma processing method includes the steps of: preparing (a) a film to be etched and (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface that defines at least one opening on the upper surface of the film to be etched; determining the ratio of the film thickness of the photoresist film to the dimensions of the opening; forming a first film on the photoresist film if the ratio is 1 or more and less than 2; forming a first film on the photoresist film and a second film on the first film if the ratio is less than 1; and trimming the photoresist film by etching at least a portion of the side surface of the photoresist film, wherein the first film includes at least (c) a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, the first portion being thicker than the second portion, and the second film is formed (d) on at least the first portion of the first film.

[0039] 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.

[0040] <Configuration of Plasma Processing Device 1> Figure 1 is a schematic diagram showing a plasma processing apparatus 1 according to one exemplary embodiment. The plasma processing method according to one exemplary embodiment (hereinafter referred to as "this processing method") may be performed using the plasma processing apparatus 1.

[0041] The plasma processing apparatus 1 is an inductively coupled plasma processing apparatus. The plasma processing apparatus 1 includes a plasma processing chamber 10, a gas supply unit 20, a power supply 30, and an exhaust system 40. The plasma processing chamber 10 includes a dielectric window 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 wall 102 of the plasma processing chamber 10, and the substrate support unit 11. 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 the gas supply unit 20, which will be described later, and the gas outlet is connected to the exhaust system 40, which will be described later. The substrate support section 11 is positioned within the plasma processing space and has a substrate support surface for supporting the substrate.

[0042] 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 (substrate support surface) 111a for supporting the 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 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. In one embodiment, the main body portion 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 placed on the base. The upper surface of the electrostatic chuck has a 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 in the figures, the substrate support 11 may also include a temperature control module configured to adjust at least one of the electrostatic chuck, ring assembly 112, and 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.

[0043] 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 Center Gas Injector (CGI) 13. The Center 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 Center Gas Injector 13 has at least one gas supply port 13a, at least one gas flow path 13b, and at least one gas inlet 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 Center 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.

[0044] 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 introduction unit 13 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.

[0045] 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 member of the substrate support 11 and the antenna 14. This causes plasma to be formed from at least one processing gas supplied to the plasma processing space 10s. Thus, the RF power supply 31 can function as at least part of the plasma generation unit 12. Furthermore, by supplying a bias RF signal to the conductive member of the substrate support 11, a bias potential is generated on the substrate W, and ions in the formed plasma can be drawn into the substrate W.

[0046] In one embodiment, the RF power supply 31 includes a first RF generation unit 31a and a second RF generation unit 31b. The first RF generation unit 31a is coupled to the antenna 14 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 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. The second RF generation unit 31b is coupled to a conductive member 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 lower frequency than 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 generation unit 31b may be configured to generate a plurality of bias RF signals having different frequencies. The generated bias RF signals are supplied to the conductive member of the substrate support 11. In addition, in various embodiments, at least one of the source RF signal and the bias RF signal may be pulsed.

[0047] Furthermore, the power supply 30 may include a DC power supply 32 coupled to the plasma processing chamber 10. The DC power supply 32 includes a bias DC generation unit 32a. In one embodiment, the bias DC generation unit 32a is connected to a conductive member of the substrate support unit 11 and configured to generate a bias DC signal. The generated bias DC signal is applied to the conductive member of the substrate support unit 11. In one embodiment, the bias DC signal may be applied to other electrodes, such as electrodes in an electrostatic chuck. In various embodiments, the bias DC signal may be pulsed. The bias DC generation unit 32a may be provided in addition to the RF power supply 31, or it may be provided in place of the second RF generation unit 31b.

[0048] The antenna 14 includes one or more coils. In one embodiment, the antenna 14 may include an outer coil and an inner coil arranged coaxially. In this case, the RF power supply 31 may be connected to both the outer coil and the inner coil, or to either the outer coil or the inner coil. In the former case, the same RF 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.

[0049] 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.

[0050] The control unit 50 processes computer-executable instructions that cause the plasma processing apparatus 1 to perform the various processes described herein. The control unit 50 may be configured to control each element of the plasma processing apparatus 1 to perform the various processes described herein. In one embodiment, part or all of the control unit 50 may be included in the plasma processing apparatus 1. The control unit 50 may include, for example, a computer 50a. The computer 50a may include, for example, a processing unit (CPU: Central Processing Unit) 50a1, a storage unit 50a2, and a communication interface 50a3. The processing unit 50a1 may be configured to perform various control operations based on a program stored in the storage unit 50a2. The storage unit 50a2 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 50a3 may communicate with the plasma processing apparatus 1 via a communication line such as a LAN (Local Area Network).

[0051] <Configuration of the PCB processing system PS> Figure 2 is a schematic diagram showing a substrate processing system PS according to one exemplary embodiment. This processing method may be performed using the substrate processing system PS.

[0052] The substrate processing system PS comprises substrate processing chambers PM1 to PM6 (hereinafter collectively referred to as "substrate processing modules PM"), a transport module TM, load lock modules LLM1 and LLM2 (hereinafter collectively referred to as "load lock modules LLM"), a loader module LM, and load ports LP1 to LP3 (hereinafter collectively referred to as "load ports LP"). The control unit CT controls each component of the substrate processing system PS to perform predetermined processing on the substrate W.

[0053] The substrate processing module PM performs processes such as etching, trimming, film deposition, annealing, doping, lithography, cleaning, and ashing on the substrate W. Part of the substrate processing module PM may be a measurement module, which may measure, for example, the film thickness of a film formed on the substrate W or the dimensions of a pattern formed on the substrate W using an optical method. The plasma processing apparatus 1 shown in Figure 1 is an example of a substrate processing module PM.

[0054] The transport module TM has a transport device for transporting substrates W, and transports substrates W between substrate processing modules PM or between substrate processing modules PM and load lock modules LLM. The substrate processing modules PM and load lock modules LLM are located adjacent to the transport module TM. The transport module TM, substrate processing modules PM, and load lock modules LLM are spatially separated or connected by gate valves that can be opened and closed.

[0055] Load lock modules LLM1 and LLM2 are installed between the transport module TM and the loader module LM. The load lock modules LLM can switch the internal pressure between atmospheric pressure and vacuum. The load lock modules LLM transport the substrate W from the loader module LM, which is under atmospheric pressure, to the transport module TM, which is under vacuum, and also transport it from the transport module TM, which is under vacuum, back to the loader module LM, which is under atmospheric pressure.

[0056] The loader module LM has a transport device for transporting substrates W, and transports substrates W between the load lock module LLM and the load board LP. Inside the load port LP, a FOUP (Front Opening Unified Pod) capable of holding, for example, 25 substrates W, or an empty FOUP can be placed. The loader module LM takes substrates W from the FOUP in the load port LP and transports them to the load lock module LLM. The loader module LM also takes substrates W from the load lock module LLM and transports them to the FOUP in the load board LP.

[0057] The control unit CT controls each component of the substrate processing system PS to execute predetermined processing on the substrate W. The control unit CT stores a recipe that sets the process procedure, process conditions, transport conditions, etc., and controls each component of the substrate processing system PS to execute predetermined processing on the substrate W according to the recipe. The control unit CT may also perform some or all of the functions of the control unit 50 of the plasma processing apparatus 1 shown in Figure 1.

[0058] <An example of this processing method> Figure 3 is a flowchart illustrating an example of this processing method. As shown in Figure 3, this processing method includes a step of preparing a substrate (preparation step: step ST1), a step of trimming a photoresist film (trimming step: step ST2), and a step of etching the film to be etched (etching step: step ST3). Each step may be performed in any substrate processing module PM within the substrate processing system PS. Multiple steps may be performed consecutively within a single substrate processing module PM. In step ST1, a substrate with a patterned resist formed on it may be provided. That is, after steps ST11 and ST12 are performed in one or more substrate processing modules PM within the substrate processing system PS, steps ST13 and ST14 may be performed in other substrate processing modules PM different from the one or more substrate processing modules mentioned above. Steps ST11 and / or ST12 may also be performed outside the substrate processing system PS.

[0059] Figures 4A and 4B show an example of a substrate W. Figure 4A is a top view of the substrate W. Figure 4B is a cross-sectional view AA' of the substrate W. Figures 4A and 4B show the substrate W in part of the preparation process described later. The substrate W has a structure in which a base film UF, an etchable film EF, and a photoresist film PR are laminated. A predetermined pattern is formed on the photoresist film PR. As shown in Figure 4A, the photoresist film PR in this example has a pattern in which multiple openings OP are repeatedly arranged at regular intervals when viewed in plan view of the substrate W (when the substrate W is viewed from top to bottom in Figure 4B).

[0060] Figure 5 is a schematic diagram showing an example of the cross-sectional structure of the substrate W, following the flow of this processing method. Figure 5A shows the cross-sectional structure of the substrate W after processing in steps ST11 and ST12, Figure 5B shows the cross-sectional structure of the substrate W after processing in step ST13, Figure 5C shows the cross-sectional structure of the substrate W after processing in step ST14, Figure 5D shows the cross-sectional structure of the substrate W after processing in step ST2, and Figure 5E shows the cross-sectional structure of the substrate W after processing in step ST3.

[0061] An example of the processing method shown in Figure 3 will be described below, with reference to the respective figures. The processing in each step may be performed in the substrate processing module PM (see Figure 2) of the substrate processing system PS. The etching process in each step may be performed in the plasma processing apparatus 1 shown in Figure 1. The processing in one step of the processing method may be performed in one module of the substrate processing module PM, and the processing in other steps of the processing method may be performed in other modules of the substrate processing module PM. The processing in multiple steps of the processing method may be performed consecutively in one module of the substrate processing module PM.

[0062] In step ST1, the substrate W is prepared. Step ST1 includes the steps of forming the etchable film EF (step ST11), forming the photoresist film PR (step ST12), forming the first film TD1 (step ST13), and forming the second film (step ST14).

[0063] In step ST11, the film to be etched EF is formed on the underlayer film UF (Figure 5A). The underlayer film UF is, for example, an organic film such as a spin-on carbon film (SOC) or amorphous carbon film formed on a silicon wafer (including both cases where it is formed on the surface of the silicon wafer and where it is formed on top of other films formed on the silicon wafer). The film to be etched EF is, for example, a dielectric film such as a silicon oxide film, silicon nitride film, SiARC, or SiON. The underlayer film UF and / or the film to be etched EF may be formed by CVD, ALD, spin coating, etc. The underlayer film UF and / or the film to be etched EF may be a flat film or a film with irregularities.

[0064] In step ST12, a photoresist film PR is formed on the film EF to be etched (see Figure 5A). The photoresist film PR has a top surface TS, a side surface SS continuous with the top surface TS, and a bottom surface in contact with the film EF to be etched. The photoresist film PR also has at least one opening OP. The opening OP is defined by the side surface SS of the photoresist film PR. The opening OP is a space on the film EF to be etched surrounded by the side surface SS. That is, in Figure 5A, the top surface of the film EF to be etched is covered by the photoresist film PR, and the photoresist film PR has a portion covered by the top surface and a portion exposed at the bottom surface BS of the opening OP.

[0065] The side surface SS of the photoresist film PR has a portion SC that protrudes from the side surface SS towards the opening OP. The portion SC is, for example, a portion that protrudes from the side surface SS of the photoresist film PR and extends to at least a part of the upper surface of the film EF to be etched. The portion SC may be, for example, scum of the photoresist film PR that exists around or near the bottom surface BS of the opening OP. This scum is, for example, residual resist that could not be completely removed in the process of forming the opening OP on the photoresist film PR (e.g., the development process). The portion SC may also be a protrusion that projects from the side surface SS toward the opening OP in a region of the side surface SS that is far from the bottom surface BS. This protrusion is a portion of the side surface SS that protrudes toward the opening OP more than its surroundings or periphery. This protrusion may be scum of the photoresist film PR. The side surface SS may have depressions or cracks (including breaks in patterns such as line patterns).

[0066] The aperture OP may have any shape in a plan view of the substrate W (when the substrate W is viewed from top to bottom in Figure 5A). This shape may be, for example, a circle, an ellipse, a rectangle, a line, or a combination of one or more of these. The photoresist film PR may have multiple apertures OP. As shown in Figure 4A, the multiple apertures OP may each have a hole shape and form an array pattern arranged at regular intervals. Alternatively, the multiple apertures OP may each have a line shape and form a line-and-space pattern arranged at regular intervals.

[0067] Two or more of the photoresist film PR, the film to be etched EF, and the underlayment film UF may function as a multilayer resist. For example, if the substrate W has another film further beneath the underlayment film UF, the multilayer film of the photoresist film PR, the film to be etched EF, and the underlayment film UF may be used as a multilayer resist to etch the other film. The multilayer resist film may include, for example, an organic film or other dielectric films or inorganic films. Examples of organic films include spin-on carbon films (SOC) and amorphous carbon. Examples of dielectric films include silicon oxide films, silicon nitride films, SiARC, and SiON. The photoresist film PR, or metal-containing film MF, may be a film containing at least one metal selected from the group consisting of tin (Sn), hafnium (Hf), indium (In), titanium (Ti), and zirconium (Zr), and in one example, a Sn-containing film. The photoresist film PR may be formed by vapor deposition methods such as CVD, MLD, or ALD, or by liquid deposition methods such as spin coating. The aperture OP may be formed in the photoresist film PR by lithography, or by etching the photoresist film PR. In one example, first, a photoresist film containing a metal such as tin is formed on the film to be etched EF. Then, using an exposure mask, the photoresist film is selectively irradiated with light (e.g., an EUV excimer laser) to expose the photoresist film with a pattern of the shape corresponding to the exposure mask. Before exposure, a pre-exposure bake may be performed to remove the solvent from the photoresist film, or after exposure, a post-exposure bake may be performed to harden the photoresist film. Then, the photoresist film after exposure is developed. Development may be performed by dry development using heat or plasma, or by wet development using a developer solution. For example, when developing using plasma, the photoresist film after exposure may be exposed to plasma generated from a gas containing a halogen compound such as hydrogen fluoride. Based on the above, a photoresist film PR having an aperture OP may be formed.

[0068] In step ST13, a first film TD1 is formed (see Figure 5B). The first film TD1 is formed to have at least a portion formed on the upper surface TS of the photoresist film PR and a portion formed on the side surface SS of the photoresist film PR. The first film TD1 may also be formed on the etched film EF exposed on the bottom surface BS of the opening OP. The film thickness of the portion of the first film TD1 formed on the upper surface TS may be thicker than the film thickness of the portion formed on the side surface SS and the portion formed on the bottom surface BS. Furthermore, the surface roughness (including the number and size of irregularities) of the portion of the first film TD1 formed on the side surface SS may be less than that of the side surface SS of the photoresist film PR.

[0069] Furthermore, the portion of the first film TD1 formed on the upper surface TS of the photoresist film PR may be formed to protrude from the upper surface TS to the opening OP in a plan view of the substrate W. This portion may be formed to overlap, for example, part or all of the portion SC in a plan view of the substrate W. The surface of this portion may be curved or flat.

[0070] The first film TD1 is, for example, an organic film. The first film TD1 is formed by PECVD using plasma generated from a process gas containing a hydrocarbon (CxHy) system (x and y are positive numbers). The process gas is C t H u F v The gas may contain a system (t and v are positive numbers; u is a number greater than or equal to 0). For example, the processing gas may be a gas containing CH3F or C4F6. The processing gas may also further contain an inert gas such as N2. The first film TD1 is formed by adjusting the film formation conditions such that the film thickness on the top surface TS is thicker than the film thickness on the side surface SS and bottom surface BS. The first film TD1 may be an inorganic film, such as a Si-containing film.

[0071] In step ST14, a second film TD2 is formed (see Figure 5C). The second film TD2 is formed on at least the portion of the first film TD1 formed on the top surface TS. The second film TD2 may be selectively formed on the portion of the first film TD1 formed on the top surface TS. Furthermore, the second film TD2 may be formed on the portions of the first film TD1 formed on the side surface SS and the bottom surface BS. The surface of this portion may be curved or flat.

[0072] The second film TD2 is, for example, an inorganic film such as a Si-containing film. The second film TD2 is formed by PECVD using plasma generated from a Si-containing gas. By adjusting the deposition conditions, the second film TD2 is selectively formed on the portion of the first film TD1 formed on the upper surface TS. The second film TD2 may also be, for example, a non-metallic inorganic film containing boron, phosphorus, or sulfur, or a metallic film containing tin, tungsten, titanium, or aluminum.

[0073] In step ST2, the partial SC of the photoresist film PR is trimmed (see Figure 5D). The trimming of the partial SC may be performed by anisotropically etching a portion of the first film TD1, a portion of the second film TD2, and the partial SC of the photoresist film PR using plasma generated from one or more processing gases. Alternatively, a portion of the first film TD1 and a portion of the second film TD2 may be etched anisotropically as well as isotropically. The one or more processing gases are such that the etching rate of the photoresist film PR and / or the first film TD1 with respect to the plasma is greater than the etching rate of the second film TD2 with respect to the plasma. For example, if the first film TD1 is an organic film and the second film TD2 is a Si-containing film, the one or more gases may include an oxygen-containing gas and a halogen-containing gas.

[0074] Furthermore, in step ST2, after trimming the photoresist film PR, a predetermined film may be further formed on at least the sidewall SS of the photoresist film PR. Then, the photoresist film PR with the predetermined film formed on the sidewall SS may be further trimmed. This allows the photoresist film PR to be appropriately trimmed even if the thickness of the first film TD1 and / or the second film TD2 is insufficient. In one example, after trimming the photoresist film PR in step ST2, the dimensions (diameter) of the opening OP formed in the photoresist film PR may be measured, and a predetermined film may be formed on at least the sidewall SS of the photoresist film PR based on the measured dimensions. The predetermined film may also be formed on the sidewall of the first film TD1 and / or the sidewall of the second film TD2 that define the opening OP. The predetermined film may also be formed on the upper surface of the second film TD2. The predetermined film may be formed from the same material as the first film TD1 or the same material as the second film TD2. Furthermore, the predetermined film may be a laminated film consisting of a film formed from the same material as the first film TD1 and a film formed from the same material as the second film TD2. The thickness of the predetermined film may be set based on the dimensions (diameter) of the opening OP formed in the photoresist film PR.

[0075] The dimensions of the aperture OP may be measured using an optical measuring device. This measuring device may be one of the substrate processing modules PM shown in Figure 2. For example, when this processing method processes multiple substrates W (e.g., 25 substrates) as a single unit (hereinafter also referred to as a "lot"), the dimensions of the aperture OP may be measured for each substrate included in the lot. Alternatively, the dimensions of the aperture OP may be measured for a specific substrate included in a lot, and this measured value may be used as the dimensions of the aperture for that specific substrate and for other substrates included in that lot. Among the multiple substrates included in a lot, the substrate to be measured may be (a) the first substrate on which this processing method is performed in that lot, (b) the last substrate on which this processing method is performed, or (c) a substrate on which this processing method is performed other than the first and last.

[0076] In step ST3, the film to be etched EF is etched (see Figure 5E). The film to be etched EF is anisotropically etched using the photoresist film PR, the first film TD1, and the second film TD2 as masks. That is, the film to be etched EF is anisotropically etched in the depth direction of the opening OP, starting from the portion exposed at the bottom surface BS of the opening OP.

[0077] The film to be etched EF may be etched by a method that selectively etches the film to be etched EF with respect to the first film TD1 and the photoresist film PR. If the film to be etched EF is a silicon oxide film, silicon nitride film, or Si-containing film such as SiON, the processing gas used for etching the film to be etched EF may be a fluorocarbon gas and / or a hydrofluorocarbon gas.

[0078] Next, examples and reference examples of this processing method will be described. This disclosure is not limited in any way by the following examples.

[0079] <Examples> In this embodiment, the substrate W has a structure in which an organic film (first film TD1) and a Si-containing film (second film TD2) are stacked in the order of a laminated structure of an SOC film (underlayment film UF), a SiON film (etched film EF), and a photoresist film (photoresist film PR) (see Figure 5C). The aperture pattern of the photoresist film is the hole pattern shown in Figure 4A, similar to the reference example.

[0080] In this example, an organic film (first film TD1) was formed by PECVD using a mixed gas of CH4 and Ar. A Si-containing film (second film TD2) was formed by PECVD using a mixed gas of SiCl4, H2, and Ar. After the formation of the organic film and the Si-containing film, a portion of the organic film, a portion of the Si-containing film, and a portion of the photoresist film were etched by plasma etching using a mixed gas of O2, HBr, and Ar. Then, the SiON film was etched using the organic film, the Si-containing film, and the photoresist film as masks. The SiON film was etched using plasma generated from a mixed gas of CHF-based gas, NF3, N2, and Ar.

[0081] <Reference example> In the reference example, the substrate W has the same structure as in the embodiment, with the SOC film (underlying film UF), the SiON film (etched film EF), and the photoresist film (photoresist film PR) stacked in this order (see Figure 5A). The aperture pattern of the photoresist film is the hole pattern shown in Figure 4A. In the reference example, after forming the aperture pattern on the photoresist film, the SiON film was etched using the photoresist film as a mask. The SiON film was etched using plasma generated from a mixed gas of CHF-based gas, NF3, N2, and Ar.

[0082] Table 1 shows the measurement results of CD (Critical Dimension) and LCDU (Local Critical Dimension Uniformity: 3σ of CD) of the aperture OP in the examples and reference examples. In Table 1, "Photoresist film" refers to the measurement results of apertures formed in the photoresist film, and "SiON film" refers to the measurement results of apertures formed in the SiON film. CD is the average value. [Table 1]

[0083] As shown in Table 1, the measurement results in the examples were better than those in the reference examples. Specifically, the LCDDU of the apertures of the SiON film in the examples was significantly improved compared to the LCDDU of the apertures of the SiON film in the reference examples. In other words, the uniformity of the CD of the apertures of the SiON film was significantly improved in the examples. Furthermore, in the examples, the CD of the SiON film became close to that of the photoresist film. Although the CD of the SiON film in the reference examples is considerably smaller than that of the photoresist film, the value obtained by multiplying the LCDDU of the SiON film by CD also showed a significant improvement in the examples compared to the reference examples.

[0084] In this processing method, a first film TD1 is formed on the photoresist film PR, and a second film TD2 is further formed on the first film TD1. Therefore, partial SC present on the side surface SS that defines the opening of the photoresist film PR can be selectively removed or reduced. Furthermore, even if depressions or cracks (including breaks in patterns such as line patterns) exist on the side surface SS that defines the opening of the photoresist film PR, these depressions can be filled in or reduced by forming the first film TD1 on the photoresist film PR. As a result, the surface roughness of the side surface SS that defines the opening OP of the photoresist film PR can be reduced, and the dimensions or shape of the opening OP can be appropriately controlled. Moreover, in this processing method, the film to be etched EF is etched using the photoresist film PR (and / or the first film TD1 and / or the second film TD2) as a mask, so the dimensions or shape of the openings formed in the film to be etched EF can be appropriately controlled.

[0085] Furthermore, in this processing method, a first film TD1 and a second film TD2 are selectively formed on the photoresist film PR. That is, in this processing method, the first film TD1 and the second film TD2 are formed such that the film thickness of the portion formed on the upper surface TS of the photoresist film PR is thicker than the film thickness of the portion formed on the side surface SS. As a result, even when the film thickness of the photoresist film PR is thin, the film to be etched EF can be etched with a sufficient selectivity ratio between the film to be etched EF and the etching mask (photoresist film PR and the first film TD1 and the second film TD2).

[0086] <Modification 1 of this processing method> Figure 6 is a flowchart showing a modified version of the processing method. This example differs from the example shown in Figure 3 in that the preparation step ST1 further includes a step ST121 for determining the thickness of the photoresist film PR. In other words, in this example, the remaining steps in the preparation step ST1 differ based on the thickness of the photoresist film PR formed in step ST12.

[0087] After the photoresist film PR is formed in step ST12, in step ST121, the dimensions of the opening OP formed in the photoresist film PR (for example, the diameter of the opening OP) and the thickness of the photoresist film PR are measured. Then, the ratio of the film thickness of the photoresist film PR to the dimensions of the opening OP (hereinafter also referred to as the "aspect ratio") is calculated. If the aspect ratio is 2 or more, steps ST13 and ST14 are skipped and preparation step ST1 is terminated. Then, in step ST2, a portion SC of the photoresist film PR is trimmed. This trimming is performed, for example, by anisotropic etching of the photoresist film PR. The first thickness may be arbitrarily determined based on the thickness and material of the film EF to be etched, the type of processing gas used to etch the film EF, etc.

[0088] If the aspect ratio is 1 or greater and less than 2, a first film TD1 is formed on the photoresist film PR in step ST13, similar to Figure 3. Then, step 14 is skipped and preparation step ST1 is completed. Then, in step ST2, a portion SC of the photoresist film PR is trimmed. The second thickness may be arbitrarily determined based on the thickness and material of the first film TD1, the thickness and material of the film EF to be etched, the type of processing gas used for etching the film EF to be etched, etc.

[0089] If the aspect ratio is less than 1, steps ST13 and ST14 are performed as in Figure 3 to complete preparation step ST1. Then, as in Figure 3, the portion SC of the photoresist film PR is trimmed in step ST2.

[0090] In step ST121, the dimensions of the aperture OP and the thickness of the photoresist film PR may be measured using an optical measuring device. This measuring device may be one of the substrate processing modules PM shown in Figure 2. For example, when this processing method processes multiple substrates W (e.g., 25 substrates) as one unit (hereinafter also referred to as "lot"), the dimensions of the aperture OP and / or the thickness of the photoresist film PR may be measured for each substrate included in the lot. In addition, in step ST121, the dimensions of the aperture OP and / or the thickness of the photoresist film PR may be measured for a specific substrate included in one lot, and the aspect ratio calculated from these measured values ​​may be used as the aspect ratio of that specific substrate and the other substrates included in that lot. Among the multiple substrates included in one lot, the substrate to be measured may be any of the following in the lot: (a) the substrate on which this processing method is first performed, (b) the substrate on which this processing method is last performed, or (c) the substrate on which this processing method is performed other than the first and last.

[0091] According to this example, the preparation steps for trimming the photoresist film can be appropriately selected based on the film thickness of the photoresist film.

[0092] <Modification 2 of this processing method> Figures 7 to 9 are flowcharts showing modified examples of this processing method. These examples differ from the example shown in Figure 3 in that, in addition to step ST2, they include steps (ST1-a, ST1-b) in which at least a portion of the side surface of the photoresist film PR is trimmed between steps ST12 and ST13 and between steps ST13 and ST14. More specifically, the example shown in Figure 7 includes a step (ST1-a) between steps ST12 and ST13 in which a portion SC of the photoresist film PR is trimmed using plasma generated from one or more processing gases. The example shown in Figure 8 includes a step (ST1-b) between steps ST13 and ST14 in which a portion of the first film TD1 (for example, at least a portion of the second portion of the first film TD) and a portion SC of the photoresist film PR are trimmed using plasma generated from one or more processing gases. In the example shown in Figure 9, between steps ST12 and ST13, there is a step (ST1-a) in which a portion SC of the photoresist film PR is trimmed using plasma generated from one or more processing gases, and between steps ST13 and ST14, there is a step (ST1-b) in which a portion of the first film TD1 (for example, at least a portion of the second portion of the first film TD) is trimmed using plasma generated from one or more processing gases. In the example shown in Figure 9, in step ST1-a, a portion of the portion SC of the photoresist film PR may be trimmed, and in step ST1-b, a portion of the first film TD and the remaining portion of the photoresist film PR may be trimmed.

[0093] According to this example, the partial SC present on the side surface SS that defines the opening of the photoresist film PR can be removed or reduced with greater precision and selectively.

[0094] Each of the embodiments described above is for illustrative purposes only and can be modified in various ways without departing from the scope and spirit of this disclosure. For example, this processing method can be carried out using a plasma processing apparatus that uses any plasma source other than the inductively coupled plasma plasma processing apparatus 1, such as a capacitively coupled plasma or microwave plasma.

[0095] Furthermore, this disclosure includes the following embodiments.

[0096] (Note 1) A preparation step for preparing a substrate having (a) a film to be etched, (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface that defines at least one opening on the upper surface of the film to be etched, and (c) a first film comprising at least a first portion and a second portion, wherein the first portion is a portion formed on the upper surface of the photoresist film, the second portion is a portion formed on the side surface of the photoresist film, and the first portion is thicker than the second portion. A trimming step of etching at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film. A plasma treatment method including [specific details omitted].

[0097] (Note 2) The plasma treatment method according to Appendix 1, wherein the preparation step includes the step of forming a second film on at least a first portion of the first film.

[0098] (Note 3) The aforementioned preparation step is, The etched film and, A step of preparing a substrate having the aforementioned photoresist film, A step of trimming at least a portion of the side surface of the photoresist film, A step of forming a first film on the trimmed photoresist film, including, Plasma treatment method as described in Appendix 1 or 2.

[0099] (Note 4) The plasma treatment method according to Appendix 2 or 3, further comprising, after the trimming step, an etching step of etching the film to be etched using the photoresist film, the first film, and the second film as masks.

[0100] (Note 5) The plasma treatment method according to any one of the appendices 1 to 4, wherein the side surface of the photoresist film has at least one of a recessed portion and a portion that protrudes from the side surface into the opening.

[0101] (Note 6) The plasma treatment method according to Appendix 5, wherein the protruding portion extends from the side surface of the photoresist film to the upper surface of the film to be etched.

[0102] (Note 7) The plasma treatment method according to Appendix 2, wherein the first film is an organic film and the second film is an inorganic film.

[0103] (Note 8) The plasma treatment method according to any one of the appendices 1 to 7, wherein the photoresist film is a Sn-containing film.

[0104] (Note 9) The plasma treatment method according to Appendix 7, wherein the inorganic film is a metal-containing film or a Si-containing film.

[0105] (Note 10) The plasma treatment method described in Appendix 9, wherein the metal-containing film is a Sn-containing film.

[0106] (Note 11) The plasma treatment method according to Appendix 9, wherein the metal-containing film is a W-containing film, a Ti-containing film, or an Al-containing film.

[0107] (Note 12) The plasma treatment method according to Appendix 7, wherein the inorganic film is a nonmetallic inorganic film containing boron, phosphorus, or sulfur.

[0108] (Note 13) The trimming process is performed using plasma generated from a predetermined processing gas. The plasma processing method according to any one of the appendices 1 to 7, wherein the etching rate of the first film with respect to the generated plasma is greater than the etching rate of the second film with respect to the generated plasma.

[0109] (Note 14) The plasma treatment method described in Appendix 13, wherein the predetermined treatment gas includes an oxygen-containing gas and a halogen-containing gas.

[0110] (Note 15) The first film and the second film are formed by plasma CVD, according to the plasma treatment method described in any one of appendices 2, 4, and 7.

[0111] (Note 16) The first film is formed using plasma generated from a gas containing a carbon-containing gas, The second film is formed using plasma generated from a gas containing a Si gas. The plasma treatment method described in Appendix 15.

[0112] (Note 17) The plasma treatment method according to Appendix 16, wherein the carbon-containing gas is CxHy (x, y are integers of 1 or more), CtHuFv (t, v are integers of 1 or more, u is an integer of 0 or more), CO, or CO2.

[0113] (Note 18) The plasma treatment method according to any one of the appendices 2, 4, and 7 to 12, wherein the thickness of the first portion of the first film is thicker than the thickness of the photoresist film and the thickness of the second film.

[0114] (Note 19) The etching step is the plasma treatment method according to Appendix 4, wherein the etching step etches the film to be etched and the second film.

[0115] (Note 20) The plasma treatment method according to Appendix 19, wherein the etched film is a Si-containing film, and the second film is a Si-containing film.

[0116] (Note 21) The plasma treatment method according to Appendix 4, 19, or 20, wherein the trimming step and the etching step are performed in the same chamber.

[0117] (Note 22) The aforementioned trimming process is A step of measuring the dimensions of the opening defined on the etched film by the etched side surface in the trimming step, A step of forming a third film on the side surface etched in the trimming step based on the measured dimensions, A step of etching a portion of the third film and A plasma treatment method according to any one of the appendices 1 to 21, further including the method described in any one of the appendices 1 to 21.

[0118] (Note 23) The plasma treatment method described in Appendix 22, wherein the third film includes an organic film.

[0119] (Note 24) The plasma treatment method according to Appendix 23, wherein the third film is a laminated film comprising the organic film and an inorganic film formed on the organic film.

[0120] (Note 25) The plasma treatment method according to any one of Appendix 22 to 24, wherein the trimming step includes repeating the steps of measuring the dimensions of the opening, forming the third film, and etching a part of the third film.

[0121] (Note 26) The system comprises a plasma processing chamber, a gas supply unit for supplying processing gas to the plasma processing chamber, a power supply unit for supplying power to generate plasma within the plasma processing chamber, and a control unit. The control unit, A substrate is provided having (a) a film to be etched, (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface that defines at least one opening on the upper surface of the film to be etched, (c) a first film comprising at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, wherein the first portion is thicker than the second portion, and (d) a second film formed on at least the first portion of the first film. The control is performed to etch at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film. Plasma processing equipment.

[0122] (Note 27) A plasma processing system comprising a first plasma processing apparatus having a first chamber and a second plasma processing apparatus having a second chamber, The first plasma processing apparatus is configured to place a substrate in a first chamber having (a) a film to be etched and (b) a photoresist film formed on the upper surface of the film to be etched and having a side surface that defines at least one opening on the upper surface of the film to be etched, and to form a first film in the first chamber having (c) a first film including at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, wherein the first portion is thicker than the second portion, and to form a second film on at least the first portion of the first film. A plasma processing system comprising a second plasma processing apparatus configured to etch at least a portion of the side surface of the photoresist film and at least a portion of the second portion of the first film.

[0123] (Note 28) (a) a film to be etched, and (b) a photoresist film formed on the upper surface of the film to be etched, having a side surface that defines at least one opening on the upper surface of the film to be etched, A step of determining the ratio of the thickness of the photoresist film to the dimensions of the opening, A step of forming a first film on the photoresist film when the ratio is 1 or more and less than 2, If the ratio is less than 1, the process involves forming a first film on the photoresist film and forming a second film on the first film. A trimming step of etching at least a portion of the side surface of the photoresist film. Includes, The first film comprises (c) at least a first portion formed on the upper surface of the photoresist film and a second portion formed on the side surface of the photoresist film, wherein the first portion is thicker than the second portion. The second film is (d) formed on at least the first portion of the first film, Plasma treatment method. [Explanation of Symbols]

[0124] 1…Plasma processing apparatus, 10…Plasma processing chamber, 11…Substrate support section, 12…Plasma generation section, 13…Central gas injection section, 13…Gas introduction section, 14…Antenna, 20…Gas supply section, 22…Flow rate controller, 30…Power supply, 31…RF power supply, 32…DC power supply, 40…Exhaust system, 50…Control section, 101…Dielectric window, 102…Side wall, 111…Main body section, 112…Ring assembly, BS…Bottom surface, CT…Control section, EF…Etched film, SC…Part, OP…Opening, PR…Photoresist film, SS…Side surface, TD1…First film, TD2…Second film, TS…Top surface, UF…Undercoat, W…Substrate

Claims

1. Plasma processing chamber and A substrate support section that supports the substrate within the plasma processing chamber, Gas supply department, Plasma generation section, Control unit and Equipped with, The control unit, The step of placing a substrate on the substrate support portion, the substrate comprising a film to be etched, a photoresist film on the film to be etched, and a first film on the photoresist film, wherein the photoresist film has a side surface defining at least one opening, and the first film includes a first portion formed on the upper surface of the photoresist film. A trimming step in which the gas supply unit and the plasma generation unit are controlled to supply trimming gas into the plasma processing chamber and generate plasma from the trimming gas, and a portion of the side surface is selectively removed from the etched film while leaving at least a portion of the first portion; A plasma processing apparatus configured to perform a process including the following.

2. Plasma processing chamber and A substrate support section that supports the substrate within the plasma processing chamber, Gas supply department, Plasma generation section, Control unit and Equipped with, The control unit, The step of placing a substrate on the substrate support portion, the substrate including the film to be etched and a photoresist film on the film to be etched, wherein the photoresist film has a side surface that defines at least one opening. The process involves controlling the gas supply unit and the plasma generation unit to supply a film-forming gas into the plasma processing chamber, generating plasma from the film-forming gas, and forming a first film on the photoresist film, wherein the first film includes a first portion formed on the upper surface of the photoresist film. A trimming step involves controlling the gas supply unit and the plasma generation unit to supply trimming gas into the plasma processing chamber, generating plasma from the trimming gas, and removing a portion of the side surface while leaving at least a portion of the first portion; A plasma processing apparatus configured to perform a process including the following.

3. The plasma generation unit is An antenna including one or more coils, An RF power supply that supplies a source RF signal to the aforementioned antenna, A plasma processing apparatus according to claim 1 or 2, comprising:

4. The plasma processing apparatus according to claim 1 or 2, wherein the gas supply unit includes at least one flow rate controller.

5. The plasma processing apparatus according to claim 4, wherein the gas supply unit further includes at least one gas source.

6. The plasma processing apparatus according to claim 1 or 2, wherein the control unit is configured to control the gas supply unit and the plasma generation unit to perform a process that further includes an etching step of supplying etching gas into the plasma processing chamber after the trimming step to generate plasma from the etching gas, and etching the film to be etched using the photoresist film and the first film as masks.

7. The side surface of the photoresist film has at least one of a recessed portion and a portion that protrudes from the side surface into the opening. The plasma processing apparatus according to claim 1 or 2, wherein the control unit controls the gas supply unit and the plasma generation unit so that at least a portion of at least one of the recessed portion and the protruding portion is removed during the trimming process.

8. The plasma processing apparatus according to claim 7, wherein the protruding portion extends from the side surface of the photoresist film to the upper surface of the film to be etched.

9. The plasma processing apparatus according to claim 1 or 2, wherein the first film further comprises a second portion formed on the side surface of the photoresist.

10. The plasma apparatus according to claim 9, wherein the film thickness of the first portion is thicker than the film thickness of the second portion.

11. The plasma processing apparatus according to claim 1 or 2, wherein the first film is an organic film.

12. The plasma apparatus according to claim 1 or 2, wherein the trimming gas includes an oxygen-containing gas and a halogen-containing gas.

13. The plasma processing apparatus according to claim 2, wherein the film-forming gas includes a carbon-containing gas.

14. The carbon-containing gas is C x H y (x, y are integers greater than or equal to 1), C t H u F v (t, v are integers greater than or equal to 1, u is an integer greater than or equal to 0), CO, or CO 2 The plasma processing apparatus according to claim 13, including the following:

15. The plasma processing apparatus according to claim 1 or 2, wherein the photoresist film is a Sn-containing film.

16. The plasma processing apparatus according to claim 1 or 2, wherein the film to be etched includes at least one selected from the group consisting of silicon oxide film, silicon nitride film, SiARC, and SiON.

17. The system comprises a first substrate processing module, a second substrate processing module, a transport module connected to the first and second substrate processing modules, and a control unit. The first substrate processing module comprises a first chamber, a first gas supply unit, and a first plasma generation unit. The second substrate processing module comprises a second chamber, a second gas supply unit, and a second plasma generation unit. The transport module includes a transport device for transporting substrates, The control unit, The process involves controlling the transport device to position a substrate containing a film to be etched and a photoresist film on the film to be etched within the first chamber, wherein the photoresist film has a side surface that defines at least one opening. The process involves controlling the first gas supply unit and the first plasma generation unit to supply a film-forming gas into the first chamber, generating plasma from the film-forming gas, and forming a first film on the photoresist film, wherein the first film includes a first portion formed on the upper surface of the photoresist film. The process of controlling the transport device to transport the substrate out of the first chamber and place the substrate in the second chamber, A trimming step in which the second gas supply unit and the second plasma generation unit are controlled to supply trimming gas into the second chamber and generate plasma from the trimming gas, thereby selectively removing a portion of the side surface from the etched film while leaving at least a portion of the first portion; A plasma processing system configured to perform a process that includes the following:

Images