Plasma treatment device, method of operating the plasma treatment device, inspection device and inspection method

Abstract

The objective of the present invention is to provide a technology that evaluates the condition of a component for a plasma processing device in a non-destructive and non-contact manner and presents the evaluation results to the user of the plasma processing device. The plasma processing apparatus of the present invention is a plasma processing apparatus having a member having a film comprising Y and O installed on its surface within a processing chamber for processing a wafer using plasma, and has a control unit that maintains the lifespan of the member when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal, thereby indicating that the damage or consumption of the film has reached a certain value or that the film has reached a certain value.

Description

Technology Field

[0001] The present invention relates to a plasma processing apparatus for forming plasma within a processing chamber inside a vacuum vessel and processing a sample to be processed, such as a semiconductor wafer, placed within the processing chamber, a method of operating the plasma processing apparatus, an inspection apparatus, and an inspection method. Background Technology

[0002] In the process of manufacturing electronic devices or magnetic memory by processing semiconductor wafers (hereinafter also simply referred to as "wafers"), plasma etching (hereinafter also referred to as "plasma etching") is applied for microfabrication to form circuit structures on the surface of the wafer. With the increasing integration of devices, processing by such plasma etching requires higher precision and yield.

[0003] Since the inner wall of the processing chamber of a plasma processing apparatus performing plasma etching is exposed to high-frequency plasma and etching gas during the etching process, the inner wall surface is protected by forming a film with excellent plasma resistance. The following are known as prior art regarding materials for such plasma-resistant films.

[0004] Patent Document 1 describes that a material constituting a film covering the surface of an earth portion disposed inside a plasma etching device comprises a Group IIIA element (having at least one selected from Sm, Eu, Gd, Tb, Dy, Ho, Er, Y, Tm, Yb, and Lu as a main component) and a fluorine element, contains a Group IIIA fluoride phase, and further comprises a crystal phase of at least 50% that is orthorhombic and belongs to the space group Pnma. Specifically, Patent Document 1 discloses the following content as an invention of a fluoride-containing film, a coating member, and a method for forming a fluoride-containing film. A film containing at least a Group IIIA element and a fluorine element, characterized by containing a Group IIIA fluoride phase, wherein the fluoride phase is orthorhombic and contains at least 50% of a crystal phase belonging to the space group Pnma. According to the present invention, for the purpose of imparting corrosion resistance to a member exposed to an atmosphere in which corrosive halogen species are present, the surface thereof is coated with a film containing a Group IIIA fluoride, and by controlling the state of the crystal phase, color change due to corrosion can be suppressed. By including a crystal phase in such a film containing a Group IIIA fluoride, corrosion resistance is improved, and by making the crystal phase orthorhombic and substantially a single phase, it is also possible to suppress color change of the film. Furthermore, by making the hardness of the film Hv100 or higher according to the micro-Vickers method, the amount of film wear can be reduced and suppressed.

[0005] Patent Document 2 describes a method in which a film on the surface of an earth portion disposed inside a plasma etching device is composed of a material comprising one or more types of Al2O3, YAG, Y2O3, Gd2O3, Yb2O3, or YF3, and Patent Document 3 describes Y3Al5O 12 , Y4Al2O9, Er2O3, Gd2O3, Y2O3, Er3Al5O 12 , Gd3Al5O12 It is described that the material is composed of a solid solution of YF3 or Nd2O3, Y4Al2O9, and Y2O3-ZrO2. Specifically, Patent Document 2 discloses the following content as an invention of an etching processing device and a member for an etching processing chamber, with the objective of "providing an etching processing device that improves processing yield by suppressing the occurrence of foreign substances." "An etching processing device that etches a sample placed inside a processing chamber within a vacuum vessel using plasma, comprising a member placed inside the processing chamber and a coating formed by spraying a predetermined material to cover the surface of the member and facing the plasma, wherein the surface of the coating is sealed using the same material as the material." Furthermore, Patent Document 3 discloses the following content as an invention of strengthening a plasma spray coating using plasma flame heat treatment. A method for forming a plasma-resistant ceramic coating on an article comprises a process of placing the article in a chamber or a spray cell of a plasma spraying system. Subsequently, ceramic powder is supplied into the plasma spraying system at a specific powder feed rate, and a plasma-resistant ceramic coating is deposited on at least one surface of the article within a plasma spraying process by the plasma spraying system. Subsequently, the plasma spraying system is used to perform in-situ plasma flame heat treatment of the plasma-resistant ceramic coating to form a crust on the plasma-resistant ceramic coating.

[0006] Patent Document 4 describes that the film material on the surface of the earth portion of a plasma etching device includes yttrium fluoride and yttrium oxyfluoride. Patent Document 4 discloses the following as an invention of a plasma treatment device and a plasma treatment method with the objective of "suppressing the generation of microparticles in a plasma process in which a gas containing a halogen-containing gas and an oxygen gas is introduced." A plasma processing apparatus (10) is provided, comprising: a pressure-reducing processing vessel (12); a lower electrode serving as a mounting platform for mounting a wafer (W) in the processing vessel; an upper electrode or antenna electrode positioned opposite to the lower electrode; a gas supply source (32) for introducing a gas containing a halogen gas and an oxygen gas into the processing vessel; a high-frequency power source (18) for applying high-frequency power for plasma generation to at least one of the upper electrode, the antenna electrode, or the lower electrode; and means for plasmaizing the gas by the high-frequency power for plasma generation and plasma processing the wafer on the mounting platform by the action of the plasma, wherein, among the surfaces exposed to the plasma in the processing vessel, at least a part or all of the surface at a height greater than the upper electrode side, the antenna electrode side, or the lower electrode side relative to the wafer mounting position is coated with a fluoride compound.

[0007] Patent documents 5, 6, and 7 describe forming a film of yttrium oxide, yttrium fluoride, or oxyyttrium oxyfluoride, with an average crystallite size of less than 100 nm, by an aerosol deposition method as a coating material for an earth portion disposed inside a plasma etching device. It is also known that the aerosol deposition method has the characteristic of being able to reduce surface irregularities compared to the above atmospheric pressure plasma spraying method. Specifically, Patent document 5 discloses the following as an invention of a plasma-resistant member with the objective of "providing a plasma-resistant member capable of increasing the adhesion strength or adhesion force of a coating covering the inner wall of a chamber, or reducing particles." "A plasma-resistant member is provided, comprising a substrate and a layered structure formed on the surface of the substrate and including a polycrystalline yttria, and having plasma resistance, wherein the layered structure comprises a first uneven structure and a second uneven structure formed superimposed on the first uneven structure and having finer unevenness than the first uneven structure." Additionally, Patent Document 6 discloses the following content as an invention of a plasma-resistant member and a method for manufacturing the same, with the objective of "providing a plasma-resistant member capable of reducing particles and stably maintaining chamber conditions." "A plasma-resistant member is provided, comprising a substrate and a layered structure having plasma resistance, wherein the layered structure comprises yttria polycrystalline bodies formed by an aerosol deposition method on the surface of the substrate, wherein the yttria polycrystalline bodies constituting the layered structure have a crystal structure in which cubic and monoclinic cells are mixed, the ratio of monoclinic cells to cubic cells among the yttria polycrystalline bodies constituting the layered structure is 0% or more and 60% or less, and the crystallite size of the yttria polycrystalline bodies constituting the layered structure is 8 nm or more and 50 nm or less." Additionally, Patent Document 7 states, "The purpose is to provide a structure capable of increasing plasma resistance."With the task of [problem], the following is disclosed as an invention of a structure: "A structure is provided having a polycrystalline yttrium oxyfluoride having an orthorhombic crystal structure as the main component, wherein the average crystallite size in the polycrystalline material is less than 100 nanometers, and when the peak intensity detected by X-ray diffraction at a diffraction angle 2θ = 32.0° is denoted as γ and the peak intensity detected at a diffraction angle 2θ = 32.8° is denoted as δ, the peak intensity ratio γ / δ is 0% or greater and 150% or less."

[0008] Meanwhile, Non-patent document 1 discloses that increasing the average crystallite size leads to an increase in the occurrence of foreign matter.

[0009] Patent Document 9 discloses a range of specific mixing ratio values ​​for granulated yttrium fluoride powder and granulated yttrium oxide as a thermal spraying material capable of obtaining a thermal spraying film of a yttrium-based fluoride compound that has sufficient corrosion resistance against plasma and can effectively prevent damage to the base material caused by acid penetration even during acid cleaning. Additionally, Patent Document 10 discloses a process for manufacturing a thermal spraying film of yttrium fluoride that can suppress particle generation, wherein a slurry containing yttrium fluoride particles having a specific average particle size is supplied to a position located downstream from the nozzle of a thermal spraying gun that emits a frame in a high-speed frame thermal spraying method, or to a position at the tip of the nozzle of a thermal spraying gun that emits a plasma jet in an atmospheric pressure plasma thermal spraying method, in a direction along the central axis of the nozzle of the thermal spraying gun. Specifically, Patent Document 9 discloses the following regarding an invention of an yttrium-based fluoride thermal spray coating and a corrosion-resistant coating comprising said thermal spray coating: "An yttrium-based fluoride thermal spray coating having a thickness of 10 to 500 μm formed on a substrate surface, characterized by an oxygen concentration of 1 to 6 mass% and a hardness of 350 HV or higher. It exhibits excellent corrosion resistance under a halogen-based gas atmosphere or a halogen-based gas plasma atmosphere, and at the same time, can effectively prevent substrate damage caused by acid penetration even during acid cleaning, and furthermore, can minimize the generation of particles caused by reaction products or detachment from the coating."

[0010] Patent Document 11 discloses a method of forming a thermal spray coating on parts, components, etc., within a plasma etching device by a suspension plasma spraying (SPS, also known as suspension plasma spraying or suspension liquid plasma spraying) method, wherein a rare earth aluminum monoclinic (R4Al2O9), in which a portion of the sites of the Al atoms of the rare earth aluminum monoclinic (R4Al2O9) are substituted with rare earth (R) atoms, is used as a raw material and sprayed in the form of a slurry dispersed in a dispersion solvent. Specifically, Patent Document 11 discloses the following contents as an invention of a thermal spraying material, a method for manufacturing the same, and a method for forming a thermal spray coating. A thermal spray coating comprising a crystalline phase of a composite oxide containing rare earth elements (R), aluminum, and oxygen, wherein the crystalline phase of the composite oxide containing rare earth elements and aluminum comprises a composition in which a portion of the sites of Al atoms in the rare earth-aluminum-monoclinic (R4Al2O9) are substituted with rare earth (R) atoms, and the composition is richer in rare earth elements than the stoichiometric composition of the rare earth-aluminum-monoclinic (R4Al2O9). It is possible to form a highly corrosion-resistant thermal spray coating with a small amount of particles generated by reaction with a halogen-based gas plasma and excellent plasma etching performance, and such a thermal spray coating is excellent as a thermal spray coating formed on parts, components, etc. within a plasma etching device used in semiconductor manufacturing processes. Prior art literature

[0011] Japan Patent Publication No. 2004-197181 Japan Patent Publication No. 2009-176787 Japan Patent Publication No. 2016-539250 Japan Patent Publication No. 2013-140950 Japan Patent Publication No. 2014-141390 Japan Patent Publication No. 2016-27624 Japan Patent Publication No. 2018-82154 Japan Patent Publication No. 2017-190475 Japan Patent Publication No. 2017-150085 Japan Patent Publication No. 2020-172702 Japan

[0012] Kazuhiro Ueda, Kazuyuki Ikenaga, Tomoyuki Tamura, Masahiro Kadoya, "Review of Crystal Structure and Foreign Contamination Mechanism of Yttrium-based Materials for Plasma Etching Devices," X-ray Analysis Research Roundtable of the Japanese Society for Analytical Chemistry (ed.), 50 Advancements in X-ray Analysis, Agne Technology Center, Issued: April 1, 2019, pp. 197-205 The problem to be solved

[0013] When a plasma treatment device is used for a long time, the surface of the inner wall material is exposed to plasma such as N, O, F, H, Cl, and Br. Due to collisions with low-speed ions, the surface of the inner wall material becomes amorphous, or the surface of the inner wall material is sputtered, and atoms of the sputtered material reattach to the surface of the inner wall material. Consequently, the surface of the inner wall material is corroded by plasma reactions, deteriorating as a plasma-resistant film and becoming a source of foreign matter. For instance, even if the average crystal size of the inner wall material is reduced, fine crystals are removed by plasma reactions, and large crystals remain on the surface of the inner wall material, so the surface of the inner wall material may become a source of foreign matter.

[0014] In addition, in the case of earthing members placed in a plasma processing device, since the deterioration of the earthing member surface cannot be evaluated in a non-destructive and non-contact manner, it is necessary to replace the earthing member after a certain operating time to suppress the occurrence of foreign matter. However, the fact that the quality of the member differs when it is new, or that the deterioration situation varies depending on the usage conditions, such as when a large amount of foreign matter occurs before replacement or when evaluating the deterioration of the earthing member after replacement reveals that there is still time before foreign matter occurs, was not sufficiently considered.

[0015] Therefore, the objective of the present invention is to provide a technology that evaluates the condition of a component for a plasma processing device in a non-destructive and non-contact manner and presents the evaluation results to the user of the plasma processing device. means of solving the problem

[0016] To solve the above problem, one of the representative plasma processing devices of the present invention is a plasma processing device having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, and has a control unit that reports that damage or consumption of the film has reached a certain value or that the lifespan of the member has been maintained when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal. Effects of the invention

[0017] According to the present invention, the condition of a component for a plasma processing device can be evaluated non-destructively and non-contactually, and the evaluation results can be presented to the user of the plasma processing device.

[0018] Problems, configurations, and effects other than those mentioned above will become clear from the description of the following forms for carrying out the invention. Brief explanation of the drawing

[0019] FIG. 1 is a cross-sectional view schematically showing the configuration of a plasma processing apparatus according to Example 1 of the present invention. Figure 2 is a cross-sectional view showing a schematic of the plasma processing device at the time of vacuum release. Figure 3 is a diagram showing an example of the spectrum of the absorption intensity of infrared radiation measured. Fig. 4 is 1300cm -1 up to 1800cm -1 This is a diagram showing an enlarged wavenumber region. Fig. 5 is 1300cm -1 up to 1800cm -1 This is a diagram showing the result of subtracting the background interpolated from the infrared absorption intensity in the wavenumber region. Figure 6 is a diagram summarizing the infrared absorption intensity of YO bonds of samples with different manufacturers or plasma treatment conditions. Figure 7 is a diagram showing the case where clustering is applied to Figure 5. Figure 8 is a diagram showing the relationship between the peak value of infrared absorption intensity and normalized lifetime of past data. Fig. 9 is 1300cm -1 up to 1800cm -1 This is a diagram showing the correlation between the peak value of the absorption intensity of clustered infrared rays in the wavenumber region and the normalized lifetime. Fig. 10 is 1300cm -1 up to 1800cm -1 This is a diagram showing the correlation between the peak value of the absorption intensity of clustered infrared rays in the wavenumber region and the normalized lifetime. Figure 11 is a drawing showing the line profile of the cross-section of the film STEM-EDX. Figure 12 is a diagram showing the STEM image of the film. Figure 13 is a drawing showing an example of a model drawing of a film. FIG. 14 is a diagram showing an example of the configuration of the control unit of a plasma processing device. Figure 15 is a diagram showing a flowchart of the operation method of a plasma processing device. FIG. 16 is a cross-sectional view showing a schematic configuration of a plasma processing apparatus according to Example 2 of the present invention. FIG. 17 is a schematic diagram showing the case where the earth electrode is removed and the absorption intensity of infrared rays is measured after the vacuum in the processing chamber of the plasma processing device is broken. Specific details for implementing the invention

[0020] (Example 1)

[0021] (Configuration of the plasma treatment device)

[0022] Example 1 of the present invention will be explained using FIGS. 1 to 6.

[0023] FIG. 1 is a cross-sectional view schematically illustrating the configuration of a plasma processing apparatus (100) according to Embodiment 1 of the present invention. The plasma processing apparatus (100) includes a member (earth electrode (22)) having a film containing Y and O installed on its surface, within a processing chamber (5) that processes a wafer (3) using plasma (13). This will be described in detail below.

[0024] The plasma processing device (100) of Example 1 is provided with a vacuum vessel having a cylindrical portion, a plasma forming portion arranged to surround the cylindrical portion above or to the side, and a vacuum exhaust portion including a vacuum pump arranged below the vacuum vessel to exhaust the inside of the vacuum vessel. Inside the vacuum vessel, a processing chamber (5), which is a space where plasma is formed, is arranged and configured to be in communication with the vacuum exhaust portion.

[0025] The upper part of the processing room (5) is a space surrounded by a cylindrical inner wall and constitutes a discharge room where plasma (13) is formed.

[0026] Inside the processing chamber (5) below the discharge chamber where plasma (13) is generated, a sample stage (4) is arranged on which a wafer (3), which is a substrate to be processed, is placed and maintained on its upper surface.

[0027] The stage (4) of Example 1 is a cylindrical member having a central axis in the vertical direction positioned concentric with or close enough to be considered as such with the discharge chamber when viewed from above, and a space is open between the bottom surface of the processing chamber (5), which has an opening communicating with the vacuum exhaust unit, and the bottom surface of the stage (4), and the stage (4) is maintained at an intermediate position between the top surface and the bottom surface with respect to the vertical direction of the processing chamber (5). The space inside the processing chamber (5) below the stage (4) is connected to the discharge chamber through a gap between the side wall of the stage (4) and the inner wall surface of the processing chamber (5) which has a cylindrical shape surrounding it, and forms an exhaust path through which products generated on the upper surface of the wafer (3) and the discharge chamber during the processing of the wafer (3) above the upper surface of the stage (4), as well as plasma and gas particles inside the discharge chamber, pass and are discharged to the outside of the processing chamber (5) by the vacuum exhaust unit.

[0028] The stage (4) of Example 1 has a substrate which is a metal member having a cylindrical shape, a heater (not shown) disposed inside a dielectric film arranged to cover the upper surface of the substrate, and multiple refrigerant passages (not shown) arranged concentrically or spirally around a central axis inside the substrate. In addition, with a wafer (3) placed on the upper surface of the dielectric film of the stage (4), a thermally conductive gas such as He is supplied into the gap between the lower surface of the wafer (3) and the upper surface of the dielectric film. To this end, a pipe through which the thermally conductive gas flows is disposed inside the substrate and the dielectric film (not shown).

[0029] Additionally, a high-frequency power source (12) is connected to the substrate of the stage (4) via a coaxial cable through an impedance matching device (11) to supply high-frequency power for forming an electric field to attract charged particles in the plasma to the upper surface of the wafer (3) during the processing of the wafer (3) by plasma. Furthermore, above the heater in the dielectric film above the substrate, a film-shaped electrode is disposed to supply DC power for generating an electrostatic force inside the dielectric film and the wafer (3) to adsorb and maintain the wafer (3) on the upper surface of the dielectric film. The film-shaped electrode is symmetrically arranged around the central axis in a plurality of radial regions from the upper and lower central axis of the approximately circular upper surface of the wafer (3) or the stage (4), and is configured to be able to assign different polarities to each.

[0030] Above the upper surface of the stage (4) of the processing room (5), a window member (2) having the shape of a disc made of dielectric material such as quartz or ceramic is provided, which is positioned opposite to it and forms the upper part of the vacuum container to hermetically seal the inside and outside of the processing room (5). Additionally, at a position below the window member (2) and forming the ceiling surface of the processing room (5), a shower plate (1) having the shape of a disc made of dielectric material such as quartz is provided, which is positioned with a gap (6) from the lower surface of the window member (2) and has a plurality of through holes (7) in the center.

[0031] The gap (6) is connected to a vacuum vessel so as to be in communication with the treatment gas supply pipe (25), and a valve (26) for opening or closing the interior is provided at a predetermined location on the treatment gas supply pipe (25). The treatment gas (treatment gas) supplied to the treatment chamber (5) has its flow rate or speed controlled by a gas flow control means (not shown) connected to one end of the treatment gas supply pipe (25), and after flowing into the gap (6) through the treatment gas supply pipe (25) with the valve (26) open, it diffuses inside the gap (6) and is supplied from above into the treatment chamber (5) through the through hole (7).

[0032] Below the vacuum vessel, a vacuum exhaust section is provided for discharging gas or particles from inside the processing chamber (5) through an exhaust port, which is an exhaust opening positioned directly below the stage (4) on the bottom surface of the processing chamber (5) and positioned with the vertical center axis being nearly identical. The vacuum exhaust section is equipped with a pressure regulating plate (14), which is a disc-shaped valve that moves up and down above the exhaust port to increase or decrease the area of ​​the flow path through which gas flows into the exhaust port, and a turbo molecular pump (10), which is a vacuum pump. Additionally, in the vacuum exhaust section, the outlet of the turbo molecular pump (10) is connected to a dry pump (9), which is a roughing pump, through an exhaust pipe, and a valve (16) is provided on the exhaust pipe.

[0033] The pressure adjustment plate (14) of Example 1 also serves as a valve for opening and closing the exhaust port. The vacuum vessel is equipped with a pressure detector (27), which is a sensor for detecting the pressure inside the processing chamber (5). A signal output from the pressure detector (27) is transmitted to a control unit (not shown) to detect a pressure value, and based on a command signal output from the control unit according to that value, the pressure adjustment plate (14) is driven so that its position in the up and down direction changes, thereby increasing or decreasing the area of ​​the exhaust passage. The control unit will be described later. Among the valve (15) and valve (17) connected to the exhaust pipe (8), valve (17) is a slow exhaust valve for slowly exhausting the processing chamber (5) from atmospheric pressure to vacuum using a dry pump (9), and valve (15) is a main exhaust valve for high-speed exhaust using a dry pump (9).

[0034] In the area surrounding the upper and side walls of the cylindrical portion at the top of the vacuum vessel constituting the processing chamber (5), a configuration is arranged to form an electric field or magnetic field supplied to the processing chamber (5) to form plasma. That is, above the window member (2), a waveguide (19), which is a conduit through which the electric field of microwaves supplied to the inside of the processing chamber (5) propagates inward, is arranged, and a magnetron oscillator (18) that generates and outputs a microwave electric field is arranged at one end thereof. The waveguide (19) has a rectangular cross-section and its axis extends in the horizontal direction, and is provided with a rectangular waveguide section in which the magnetron oscillator (18) is arranged at one end, and a circular waveguide section connected to the other end of the rectangular waveguide section, in which the central axis extends in the vertical direction and the cross-section is circular. The lower portion of the circular waveguide has a cylindrical shape with a large diameter and a cavity is arranged therein in which an electric field of a specific mode is strengthened. Additionally, a plurality of solenoid coils (20) and solenoid coils (21), which are magnetic field generating means, are provided to surround the upper portion of the cavity and its surroundings, and furthermore, the side of the processing room (5).

[0035] In this plasma processing apparatus (100), an unprocessed wafer (3) is placed in the transfer chamber of a vacuum transfer device (not shown), such as a robot arm, which is placed inside the transfer chamber of another vacuum vessel (not shown) connected to the side wall of the vacuum vessel, and is transferred into a processing chamber (5) and delivered to a stage (4) and placed on the upper surface. When the arm of the vacuum transfer device exits the processing chamber (5), the inside of the processing chamber (5) is sealed, and at the same time, a DC voltage is applied to an electrostatic adsorption electrode in the dielectric film, and the wafer is maintained on the dielectric film by the electrostatic force generated. In this state, a gas with heat transfer properties, such as He, is supplied through a pipe placed inside the stage (4) into the gap between the wafer (3) and the upper surface of the dielectric film constituting the upper surface of the stage (4), and a refrigerant whose temperature is controlled to a predetermined range by a refrigerant temperature controller not shown is supplied to the internal refrigerant flow path. Accordingly, heat transfer between the temperature-controlled substrate and the wafer (3) is promoted, and the temperature of the wafer (3) is adjusted to a value within a range suitable for initiating processing.

[0036] Processing gas, whose flow rate or speed is controlled by a gas flow rate control means, passes through the processing gas supply pipe (25) and is supplied into the processing chamber (5) through the gap (6) and through the through hole (7), while simultaneously the inside of the processing chamber (5) is exhausted from the exhaust port by the operation of the turbo molecular pump (10), and the pressure inside the processing chamber (5) is adjusted to a value within a range suitable for processing by the balance of the two. In this state, the electric field of microwaves oscillated from the magnetron oscillator (18) propagates through the inside of the waveguide (19), passes through the window member (2) and the shower plate (1), and is radiated into the inside of the processing chamber (5). In addition, a magnetic field generated from a solenoid coil (20, 21) is supplied to a processing room (5), and electron cyclotron resonance (ECR) occurs due to the interaction between the magnetic field and the electric field of the microwave, and atoms or molecules of the processing gas are excited, ionized, and dissociated, thereby generating plasma (13) inside the processing room (5).

[0037] When the plasma (13) is formed, high-frequency power from the high-frequency power source (12) is supplied to the substrate, and a bias potential is formed above the upper surface of the wafer (3). Charged particles, such as ions in the plasma (13), are attracted to the upper surface of the wafer (3), and the etching process of the film layer of the target to be processed, which has a film structure including a plurality of film layers including a film layer of the target to be processed and a mask layer formed on the upper surface of the wafer (3), proceeds along the pattern shape of the mask layer. When it is detected by a detector not shown that the processing of the film layer of the target to be processed has reached its end point, the supply of high-frequency power from the high-frequency power source (12) is stopped, the plasma (13) is extinguished, and the processing is stopped.

[0038] When the control unit determines that there is no need to proceed further with the etching process of the wafer (3), high vacuum evacuation is performed. Additionally, after the static electricity is removed and the adsorption of the wafer (3) is released, the arm of the vacuum transport device enters the processing room (5) and the wafer (3) that has completed processing is delivered, and as the arm contracts, the wafer (3) is transferred to the vacuum transport room outside the processing room (5).

[0039] (Treatment of the inner wall surface of the treatment room (5))

[0040] The inner wall surface of the processing chamber (5) is a surface that faces the plasma (13) and is exposed to the particles. Meanwhile, in order to stabilize the potential of the dielectric plasma (13), it is necessary to place a member that functions as an earth electrode that faces and contacts the plasma within the processing chamber (5).

[0041] In the plasma processing apparatus (100) of Example 1, an earth electrode (22), which is a ring-shaped member arranged to cover the lower surface of the inner wall of the processing chamber (5) surrounding the discharge chamber and to surround the upper surface of the stage (4), is arranged for the purpose of functioning as an earth electrode. This earth electrode (22) is provided with a base material (23) composed of a conductive material and a coating (24) covering the surface thereof, and in Example 1, the base material (23) of the earth electrode is composed of a metal such as a stainless steel alloy or an aluminum alloy.

[0042] If there is no coating on the surface of the base material (23), the earth electrode (22) is exposed to plasma (13) at that location, thereby becoming a source of corrosion or foreign matter that causes contamination of the wafer (3). Therefore, to suppress contamination, a coating (24) made of a material with high plasma resistance is placed on the surface of the base material (23) of the earth electrode (22) to cover the base material (23). By the coating (24) covering the base material (23), damage caused by plasma can be suppressed while maintaining the function of the earth electrode (22) as an electrode through plasma.

[0043] Additionally, the film (24) may be a laminated film. In Example 1, a film (24) was used in which fine particles of yttrium fluoride (YF3) and oxyyttrium oxyfluoride (YOF) were deposited and formed by atmospheric pressure plasma spraying using the spraying material on the surface of the base material (23) of the earth electrode (22). In the following description, the film (24) may be referred to as a YF inner wall material. Additionally, the case of the YF inner wall material of the earth electrode (22) is described, but the present disclosure is not limited to this case. The present disclosure can be applied to a member placed in the processing chamber (5) of the plasma processing device (100) other than the earth electrode (22), and can also be applied to a film for protecting the member from plasma processing, without being limited to the type of film.

[0044] Meanwhile, in the substrate (28) that does not function as an earth, a metal component such as a stainless steel alloy or an aluminum alloy is used. On the surface of the substrate (28), in order to suppress corrosion, metal contamination, and the occurrence of foreign matter caused by exposure to plasma (13), treatments such as passivation treatment, thermal spraying, physical vapor deposition (PVD), and chemical vapor deposition (CVD) are performed to improve corrosion resistance to plasma and reduce consumption.

[0045] Additionally, to reduce the interaction between the substrate (28) and the plasma (13), a cylindrical ceramic cover (not shown), such as yttrium oxide or quartz, may be placed between the inner wall surface of the cylindrical substrate (28) and the discharge chamber. By placing such a cover between the substrate (28) and the plasma (13), contact with highly reactive particles within the plasma (13) or collisions with charged particles are blocked or reduced, thereby suppressing the consumption of the substrate (28).

[0046] (Evaluation of status)

[0047] FIG. 2 is a cross-sectional view showing a schematic of the plasma processing device (100) when the vacuum is released. During maintenance, the processing chamber (5) of the plasma processing device (100) is vacuum-breaked by introducing nitrogen gas, inert gas, or atmosphere, and is lifted by a crane (not shown) equipped with a member on the upper part of the processing chamber (5) to the state shown in FIG. 2. At this time, without contacting the film (24) of the earth electrode (22), a Fourier transform infrared absorption spectrometer (29) is used to measure the spectrum of infrared intensity reflected and scattered from the surface of the film (24). The inspection device (30) evaluates the condition of the film (24) of the earth electrode (22) using the measured spectrum.

[0048] Referring to FIGS. 3 to 10, the processing procedure of the measured infrared absorption spectrum performed in the inspection device (30) is described. FIG. 3 is a diagram showing an example of the spectrum of the measured infrared absorption intensity. In FIG. 3, the vertical axis represents the infrared absorption intensity (reception intensity), and the horizontal axis represents the infrared wavenumber. FIG. 3 shows the spectra of the infrared absorption intensity of a new coating (graph labeled 'New'), a coating used for about half of its predicted lifespan (graph labeled 'In Use'), and a coating used up to its predicted lifespan (graph labeled 'Deteriorated'). The transmission absorption spectrum of Y2O3 registered in the Fourier Transform Infrared Spectroscopy (FT-IR) database is 2930 cm⁻¹ -1 , 1384cm -1 , 563cm -1 , 465cm -1 , 450cm -1 The absorption, and also the transmission absorption spectrum of YF3, is 417 cm⁻¹ -1 Wow, 401cm -1 The absorption of is shown. In Fig. 3, 2930 cm -1 The absorption is broad absorption of OH bonds (3000–3750 cm⁻¹)-1 ) or absorption of CH bonds (2750–3000 cm -1 It was not detected because it overlaps with ). Also 700cm -1 The region below shows high absorption and a steep background slope, and no absorption peak was detected. 1300 cm⁻¹ -1 up to 1800cm -1 In the wavenumber region, there is infrared absorption of the YO bond. Figure 4 shows the infrared absorption spectrum in this wavenumber region.

[0049] Next, Fig. 4 is 1300cm -1 up to 1800cm -1 This is a diagram showing an enlarged wavenumber region. In the diagram, because the background varies depending on the manufacturer or plasma processing room usage, 1300cm -1 Infrared absorption intensity and 1850cm -1 The background was interpolated using two points of infrared absorption intensity. The results are also shown in Fig. 4. In addition, '1300 cm -1 up to 1800cm -1 The notation of ' is '1300 to 1800cm -1 There are cases where it is denoted as '. The same applies to other wavenumber regions.

[0050] Next, Fig. 5 is 1300cm -1 up to 1800cm -1 This is a diagram showing the result of subtracting the background interpolated from the infrared absorption intensity in the wavenumber region. By subtracting the background, the peaks included in the infrared absorption intensity are highlighted.

[0051] Next, Figure 6 is a diagram summarizing the infrared absorption intensity of YO bonds in samples with different manufacturers or plasma treatment conditions. It can be seen that there are 2 to 6 peaks, depending on the sample. The peaks were identified, the wavenumber regions containing the peaks were classified, and clustered into 6 types ((1) to (6)).

[0052] Next, Fig. 7 is a diagram showing the case where peaks are searched according to clustering in Fig. 5. The six vertical lines indicate the positions of the peaks detected in the clustered range. Since the number of peaks detected varies depending on the spectrum, for spectra where no peaks were detected, the spectral intensity at the average wavenumber in the clustered wavenumber region was interpolated.

[0053] Next, Fig. 8 is a diagram showing the relationship between the peak values ​​of infrared absorption intensity and normalized lifetime of past data. Fig. 8 shows the 1592 cm⁻¹ of YO bonding for samples with different manufacturers or plasma treatment conditions. -1 The results are plotted with the infrared absorption intensity on the vertical axis and the normalized life value (1 representing a new product and 0 representing no remaining life, respectively) on the horizontal axis, which is the remaining life of the used film relative to the life predicted from a new product. Additionally, the curve shown in Fig. 8 is a regression curve, and it can be seen that the infrared absorption intensity takes a minimum around the normalized life of 0.4. Fig. 8 also shows the results for the film shown in Fig. 7.

[0054] Figures 9 and 10 are 1300cm -1 up to 1800cm -1 This is a diagram showing the correlation between the peak value of the absorption intensity of clustered infrared rays in the wavenumber region and the normalized lifetime. FIG. 9(a) is 1355 cm of clustering (1). -1 Near, Fig. 9(b) is 1437cm of clustering (2). -1 Near, Fig. 9 (c) is 1536 cm of clustering (3). -1 Near, Fig. 10 (a) is 1592 cm of clustering (4). -1 Near, Fig. 10(b) is 1641cm of clustering (5). -1 Near, Fig. 10 (c) is 1738 cm of clustering (6). -1This shows the correlation between the peak value of infrared absorption intensity in the vicinity and the normalized lifespan. It can be seen that in all clustered wavenumber regions, the peak value has a minimum around the normalized lifespan of 0.4. The time elapsed from the time of new use until the peak value reached a minimum (usage time) corresponds to a period of 0.6 relative to a normalized lifespan of 1. If the usage time to date (0.6) is set to 1, it can be seen that the remaining lifespan is less than 2 / 3 of the usage time. Meanwhile, the difference in intensity between the time of new use and the minimum value varies depending on the peak. The largest difference is at 1592 cm, which is Fig. 10 (a). -1 It was a peak in the vicinity.

[0055] (Consideration of the mechanism of infrared absorption peaks)

[0056] A deterioration model of the YF inner wall material is considered based on the analysis results of the absorption intensity of the YO bond. Here, as a first approximation, it is assumed that if the YF bond on the surface of the YF inner wall material decreases and the YO bond increases, the peak intensity shown on the vertical axis of Figures 9 and 10 increases, and conversely, if the YF bond increases, the absorption intensity of the YO bond decreases, and the peak value on the vertical axis of Figures 9 and 10 decreases.

[0057] FIG. 11 is a drawing showing the cross-sectional STEM-EDX line profile of a film (24). The cross-sectional STEM-EDX represents the results of analysis performed by combining a Scanning Transmission Electron Microscope and Energy Dispersive X-ray Spectroscopy. FIG. 11 (a) is the cross-sectional STEM-EDX line profile of a new film sample with a normalized lifespan of 1.0. In the region of 0.0 to 0.02 μm, the O concentration increases due to the influence of minute irregularities on the surface of the film (24), and the concentrations of Y and F decrease. In the region of 0.02 to 0.038 μm, the O concentration is thought to be high due to the influence of natural oxidation. In the 0.04–0.09 µm range, there is some variation in the concentrations of O and F, but it is similar to the range inside 0.09 µm, and Y is thought to be about 25 at%, O 20 at%, and F 55 at%.

[0058] FIG. 12 is a drawing showing a STEM image of a film (24). FIG. 12 (a) corresponds to the STEM image of a new film (24) shown in FIG. 11 (a), where (1) in FIG. 12 (a) is the brightfield image and (2) in FIG. 12 (a) is the Z contrast image. The line profile of FIG. 11 (a) is a measurement of the white line portion of FIG. 12 (a). It is shown that the surface side of the film (24) is in an uneven state.

[0059] FIG. 13 is a drawing showing an example of a model drawing of a coating (24). The upper side of the ground represents the surface of the base material(s) of the coating (24), excluding the uneven parts and the natural oxidation parts, and the lower side of the ground represents the interior of the coating (24). FIG. 13 (a) is a model drawing showing the state of the base material(s) shown in FIG. 11 (a) and FIG. 12 (a). 'YO-F3' represents the approximate ratio of the concentrations of O and F when the Y contained in the base material(s) of the coating (24) is set to 1.

[0060] When the surface of the film (24) is fluorinated by plasma treatment, the absorption strength of the YO bond decreases to approximately 0.4 of the normalization lifespan, as shown in FIGS. 9 and 10. FIG. 13 (b) shows the base material(s) near the normalization lifespan as a model. It is believed that the absorption strength of the YO bond decreases while the film (24) is fluorinated to about 3 μm from the surface. 0.6 -F5' assumes a case where the F concentration increases by approximately 60% and the O concentration decreases by approximately 40% at the surface portion of the base material(s). Here, the detection depth of FT-IR is considered to be about half the infrared wavelength used in FT-IR (about 3 μm). This is because although the materials constituting the YF inner wall materials, such as Y2O3, YF3, or Y5O4F7, are almost transparent to visible light and infrared light, the inner wall surface has irregularities of several μm and contains numerous voids or grain boundaries inside, so scattering occurs at their boundaries and specular reflection is not detected. Although the penetration depth of infrared light is considered to be about the wavelength (about 6 μm), it is estimated to be about half the wavelength by considering the length of the path escaping to the surface.

[0061] When plasma treatment is performed repeatedly, the condition of the film (24) deteriorates, and it becomes unsuitable for use as an earth electrode (22). Fig. 11 (b) shows the line profile of the cross-sectional STEM-EDX of a sample with a standardized lifespan of 0.022 μm. The O concentration is high from the surface of the film (24) to a depth of 0.022 μm, but beyond 0.022 μm, the O concentration gradually decreases and the F concentration increases. Meanwhile, since the interior has the same elemental concentration as a new product, the O concentration increases and the F concentration decreases in the interior.

[0062] Fig. 12(b) corresponds to the STEM image of the film (24) with a normalized lifespan of 0 as shown in Fig. 11(b), where (1) in Fig. 12(b) is the bright field image and (2) in Fig. 12(b) is the Z contrast image. The line profile of Fig. 11(b) is a measurement of the white line portion of Fig. 12(b). Compared to the new state of Fig. 12(a), no irregularities appear on the surface side of the film (24), and it is inferred that the surface has deteriorated due to exposure to plasma.

[0063] FIG. 13(c) is a model diagram showing the state of the base material(s) shown in FIG. 11(b) and FIG. 12(b). That is, at a standardized life of 0.4 to 0, fluorination progresses to a region deeper than 3 μm from the inner wall surface ('YO 0.6 -The region of -F5' shifts inward), the fluorine supplied by diffusion from the surface alone becomes insufficient for the fluorine required for internal fluoridation, and the fluorine in the fluorine-rich layer on the surface is replaced by internal oxygen, resulting in the surface being oxidized ('Y-O3-F 2.7 It is believed that the oxidation-prone region was measured as if it were formed on the surface of the base material(s).

[0064] When Y2O3 is fluorinated, the volume expands, and when YOF is oxidized, the volume contracts. That is, 'YO' in Fig. 13 0.6 The boundary of the -F5' region, especially 'YO' 0.6 -F5' region and 'Y-O3-F 2.7 Large residual stress (tensile stress in the stacking direction) occurs at the boundary of the region, and it is thought that cracks occur in this region and foreign matter causing deterioration is generated.

[0065] (Example of control unit configuration)

[0066] FIG. 14 is a diagram showing an example of the configuration of a control unit (50) of a plasma processing device (100). The control unit (50) includes a memory (51), a communication device (52), an input / output device (53), and a processor (54).

[0067] The memory (51) has a software program and / or instruction set executed by the processor (54). The processor (54) executes various software programs and / or instruction sets stored in the memory (51) to perform various functions for the plasma processing device (100) and process data. The memory (51) includes a non-volatile memory device such as random access memory (RAM), a magnetic disk memory device, a flash memory device, or other non-volatile solid-state memory devices. Additionally, although the plasma processing device (100) is shown as having one memory (51) and one processor (54), there may be two or more. Furthermore, the plasma processing device (100) may include a memory device other than the memory (51).

[0068] The communication device (52) is an interface for communicating information with the components of the plasma processing device (100) and with external devices of the plasma processing device (100). For example, the control unit (50) receives a signal output from the pressure detector (27) through the communication device (52) and outputs a control signal to drive the pressure adjustment plate (14). In addition, the control unit (50) manages the progress of the etching process, and when the etching process is finished, the control unit (50) controls the arm of the vacuum transport device through the communication device (52). In addition, based on the information obtained through the communication device (52), the control unit (50) can measure the time elapsed after the component is placed in the processing room (5) and measure the number of wafers (3) processed in the plasma processing device (100).

[0069] The input / output device (53) is a device used when a user performs input / output of information to the plasma processing device (100). As the input / output device (53), for example, an output device such as a display, or an input device such as a keyboard or mouse may be used. Additionally, it may be a device equipped with both input and output functions, such as a touch panel.

[0070] The memory (51) stores a software program and / or instruction set for executing the function of the plasma processing device (100), and data used for executing the function. The memory (51) includes a plasma processing management unit (510), a spectrum measurement unit (511), a background interpolation unit (512), a background difference unit (513), a lifespan measurement unit (514), a lifespan determination unit (515), a maintenance unit (516), an FT-IR database (517), and a component database (518).

[0071] When the plasma processing management unit (510) is executed by memory (51), the processor (54) manages the plasma processing performed on the wafer (3). For example, the processor (54) operates the plasma processing device (100) according to the plasma processing conditions set by the user of the plasma processing device (100). In addition, the processor (54) can acquire set data, and can acquire information such as the cumulative time during which plasma (13) was generated in the plasma processing, the number of processed wafers (3), and the usage period of the components placed in the plasma processing device (100).

[0072] When the spectrum measuring unit (511) is executed by the processor (54), the processor (54) performs a measurement of the spectrum. The processor (54) uses a Fourier transform infrared absorption spectrometer (29) to measure the spectrum of infrared intensity reflected and scattered from the surface of the film (24) of the earth electrode (22).

[0073] Additionally, when the background interpolation unit (512) is executed by the processor (54), the processor (54) interpolates the background of the infrared absorption intensity. The processor (54) selects a predetermined wavenumber region from the infrared reflection intensity acquired by the spectrum measurement unit (511), and selects two points to interpolate the background. Here, the FT-IR database (517) registers the infrared transmission absorption spectra for various materials. In the case of the present disclosure, information regarding the transmission absorption spectrum of a compound containing any one of Y, O, and F is registered, but the FT-IR database (517) may also register information regarding the transmission absorption spectrum of other compounds. Additionally, the FT-IR database (517) may also register background information regarding the manufacturer of the material or plasma processing in the plasma processing device (100). Based on the information registered in the FT-IR database (517), the processor (54) can select the wavenumber region and set the background.

[0074] Additionally, when the background difference unit (513) is executed by the processor (54), the processor (54) differs the interpolated background from the infrared absorption intensity in a predetermined wavenumber region. Additionally, the processor (54) clusters the predetermined wavenumber region to detect the peak value of the infrared absorption intensity of a predetermined wavelength. In the section where the infrared absorption intensity cannot be measured, the processor (54) interpolates the spectral intensity at the average wavenumber in the clustered wavenumber region. In the present disclosure, the predetermined wavelength is 1300 to 1850 cm -1 It is the wavelength at which the reflection intensity value reaches a maximum (peak value) within the range. Additionally, the range of the specified wavelength may be set according to the material of the member detecting the state.

[0075] Additionally, when the usage period measurement unit (514) is executed by the processor (54), the processor (54) measures the usage period that has elapsed since the earth electrode (22) was placed in the plasma processing device (100). As an indicator of the usage period, for example, the number of wafers (3) processed after the earth electrode (22) was placed in the processing room (5) or the total sum of the time (cumulative time) during which the plasma (13) was formed after the earth electrode (22) was placed in the processing room (5) can be used. The processor (54) measures the number of wafers (3) that underwent plasma processing and the cumulative time during which the plasma (13) was formed.

[0076] Additionally, when the lifespan determination unit (515) is executed by the processor (54), the processor (54) determines that the reflection intensity value of infrared rays of a predetermined wavelength detected from the surface of the film (24) of the earth electrode (22) becomes a minimum. The processor (54) repeatedly performs the processing of the spectrum measurement unit (511), the background interpolation unit (512), and the background difference unit (513) to detect the peak value of the reflection intensity of infrared rays and detects that the peak value becomes a minimum. For example, it is possible to detect the minimum of the peak value when the peak value detected repeatedly changes from decreasing to increasing over time. When a minimum is detected, it is determined that the standardized lifespan of the earth electrode (22) has become 0.4 or less.

[0077] Additionally, when the maintenance unit (516) is executed by the processor (54), the processor (54) maintains that the damage or wear of the film (24) of the earth electrode (22) has reached a certain value, or the usable limit (e.g., lifespan) of the earth electrode (22), when the absorption intensity value of infrared rays of a predetermined wavelength detected from the surface of the film (24) of the earth electrode (22) becomes minimal. As for the content to be maintained, the degree of damage or wear caused by a change in the composition of Y, O, and F contained in the surface of the film (24) after the absorption intensity value of infrared rays of a predetermined wavelength becomes minimal is maintained. For example, indicators such as the damage rate or wear rate when compared to the condition of a new earth electrode (22) may be maintained to the user of the plasma processing device (100). Additionally, the processor (54) can output information regarding the lifespan of the film (24) or the earth electrode (22) to a display, etc., among the input / output devices (53). Information regarding lifespan will be discussed later.

[0078] In this way, the user of the plasma processing device (100) can determine the extent of damage or wear of the film (24) or the lifespan of the earth electrode (22) when damage accumulates on the film (24) as the number of wafers (3) being processed or the total time of plasma (13) being formed increases after the earth electrode (22) is placed in the processing chamber (5).

[0079] (Lifespan of absence)

[0080] When the peak value of the infrared absorption intensity becomes minimal, the normalized lifespan is around 0.4, and there is remaining capacity in the earth electrode (22) to perform plasma treatment. In this case, the lifespan of the earth electrode (22) can be expressed, for example, as the number of wafers that can be processed before the maintenance of the earth electrode (22), or as the total sum of the time during which plasma (13) can be formed before the maintenance of the earth electrode (22). Furthermore, since the present disclosure assumes a case where damage occurs due to plasma treatment, the lifespan of the earth electrode (22) has the same meaning as the lifespan of the coating (24). Also, regarding the maintenance of the coating (24), the earth electrode (22) itself may be replaced, or the coating (24) of the earth electrode (22) may be newly changed.

[0081] For example, the total number of wafers (3) that can be processed and the total time of plasma (13) that can be formed are registered in the parts database (518) from the time the earth electrode (22) is used until it is replaced. In addition, the control unit (50) measures the cumulative time of the number of wafers processed and the plasma formation time until a minimum of the peak value of the reflection intensity is detected.

[0082] In the case where the maintenance point of step S8 is used as the starting point, if the control unit (50) represents the lifespan of the member (earth electrode (22)) as the number of wafers that can be processed from the maintenance of step S8 until the maintenance of the film (24), it is possible to set the number of wafers according to the lifespan to be smaller than the number of wafers until it is determined that the absorption intensity value has become minimal. Alternatively, if the control unit (50) represents the lifespan of the member (earth electrode (22)) as the total sum of the time during which plasma (13) can be formed from the maintenance of step S8 until the maintenance of the film (24), the total sum of the time according to the lifespan is set to be smaller than the total sum of the time during which plasma (13) is formed until it is determined that the absorption intensity value has become minimal.

[0083] Additionally, when the minimum peak value of the infrared absorption intensity is detected as the starting point, if the control unit (50) represents the lifespan of the member (earth electrode (22)) as the number of wafers (3) that can be processed from the time when it is determined that the absorption intensity value has become minimum until the repair work of the film (24), the number of wafers according to the lifespan is set to be smaller than the number of wafers (3) until it is determined that the absorption intensity value has become minimum. Alternatively, if the control unit (50) represents the lifespan of the member (earth electrode (22)) as the total sum of the time during which plasma (13) can be formed from the time when it is determined that the absorption intensity value has become minimum until the repair work of the film (24), the total sum of the time according to the lifespan is set to be smaller than the total sum of the time during which plasma (13) is formed until it is determined that the absorption intensity value has become minimum.

[0084] In this way, the control unit (50) converts the lifespan of the earth electrode (22) (film (24)) into the remaining number of wafers (3) that can be processed or the remaining time for forming plasma (13) until maintenance work is required, and notifies the user of the plasma processing device (100). The user can intuitively understand the lifespan of the earth electrode (22) (film (24)) and also recognize the urgency or imminence of maintenance work.

[0085] Although the configuration of the control unit (50) has been described as above, the inspection device (30) may have a configuration that includes at least a memory (51) and a processor (54), just like the control unit (50). The inspection device (30) may perform the same processing as the control unit (50) to inspect the state of the earth electrode (22).

[0086] (Flowchart of the operation method of the plasma treatment device (100))

[0087] FIG. 15 is a diagram showing a flowchart of the method of operating a plasma processing device (100). In step S1, a component is placed in the processing chamber (5) of the plasma processing device (100). The processing chamber (5) of the plasma processing device (100) is sealed, and a state is created where plasma processing can be performed on a wafer (3) in the plasma processing device (100).

[0088] Next, as step S2, the elapsed usage period after the member is placed in the processing chamber (5) is measured. As an indicator of the usage period, for example, the number of wafers processed after the earth electrode (22) is placed in the processing chamber (5) or the total sum of the time during which the plasma (13) is formed after the earth electrode (22) is placed in the processing chamber (5) can be used. The processing of steps S3 to S6 after step S2 is repeated, and the usage period is measured.

[0089] Next, as step S3, a spectrum measurement is performed. For example, the control unit (50) measures the spectrum of infrared intensity for an earth electrode (22) placed in the processing room (5).

[0090] Next, as step S4, background interpolation is performed. For example, the control unit (50) interpolates the background in a specific wavelength region among the measured infrared absorption intensities.

[0091] Next, as step S5, background difference is performed. For example, the control unit (50) takes the difference of the background interpolated in a specific wavelength region and detects the peak intensity of the infrared absorption intensity.

[0092] Next, as step S6, the detection of a minimum of the peak value is performed. For example, the control unit (50) can detect a minimum of the peak value when the repeatedly detected peak value changes from a decrease to an increase. If a minimum of the peak value is not detected (No in step S6), the measurement of the usage period continues (steps S7 and S2), and the detection of the peak intensity is repeated (steps S3 to S5).

[0093] Next, as step S8, a notification is made to the user of the plasma processing device (100). For example, if a minimum of the peak value is detected (Yes in step S6), the control unit (50) notifies the user of the plasma processing device (100) about the degree of damage or consumption of the film (24), or the lifespan (usable limit) of the earth electrode (22) (film (24)).

[0094] Although the above operating method is described as being controlled by the control unit (50) of the plasma processing device (100), it is also possible to execute the above operating method by the inspection device (30).

[0095] (Actions / Effects)

[0096] As described above, in the plasma treatment apparatus (100) of Example 1, regarding infrared rays scattered and reflected from a member placed in the treatment chamber (5), 1300 cm -1 up to 1800cm -1 An infrared absorption spectrum including the wavenumber region is measured, and at 1300 cm -1 The infrared absorption intensity of and 1800cm -1 The background is interpolated using two points of infrared absorption intensity. Next, 1437 cm -1 , 1536cm -1 , 1592cm -1 , 1641cm -1The absorption intensity of infrared radiation is measured by subtracting the background interpolated from the absorption intensity of infrared radiation in the vicinity, and it is detected that the absorption intensity of infrared radiation decreases with increasing plasma processing time. Next, it is detected that the peak value of the absorption intensity of infrared radiation has shifted to a minimum or an increase, and it is determined that the standardized lifespan has become 0.4 or less. A standardized lifespan of 0.4 or less means that the remaining time until the lifespan of the inner wall material is exhausted and foreign matter is generated is 2 / 3 or less of the usage time thus far. By showing information regarding the remaining lifespan to the user of the plasma processing device (100), the user can be made aware of the condition of the material placed in the processing room (5).

[0097] In addition, by placing a Fourier transform infrared absorption spectrometer (29) on a movable arm and measuring the absorption and scattering of infrared rays at multiple locations of the inner wall material of the earth electrode (22), it is possible to evaluate the deviation within the earth electrode (22) and detect the location where the most deterioration has occurred.

[0098] In this way, according to the present disclosure, the condition of a component for a plasma processing device can be evaluated non-destructively and non-contactually, and the evaluation result can be presented to the user of the plasma processing device.

[0099] (Example 2)

[0100] Example 2 is described using FIG. 16. FIG. 16 is a cross-sectional view showing a schematic configuration of a plasma processing device (200) according to Example 2 of the present invention. Example 2 differs from Example 1 in that it can measure the absorption intensity of infrared rays without breaking the vacuum of the processing chamber (5) of the plasma processing device. In Example 2, the plasma processing device (200) further comprises a first window (window (42)) for irradiating infrared rays onto a member placed inside the processing chamber (5), a second window (window (43)) for emitting infrared rays scattered from the member out of the processing chamber (5), and a detector (IR detector (41)) for detecting infrared rays emitted from the second window (window (43)). In the following description, components identical or equivalent to those in Example 1 are given the same reference numerals, and their descriptions are simplified or omitted.

[0101] The plasma processing device (200) includes an IR laser light source (40) and an IR detector (41), and also has windows (42 and 43) formed in the substrate (28). Infrared rays (IR) emitted from the IR laser light source (40) are introduced into the processing chamber (5) through the window (42) (e.g., Ge, Si, etc.) through which long-wavelength infrared rays are transmitted. Likewise, infrared rays (SL) scattered from the YF inner wall material are also detected by the IR detector (41) through the window (43) (e.g., Ge, Si, etc.) through which long-wavelength infrared rays are transmitted. In the case of a window material with low plasma resistance, such as Ge or Si, a gate valve (not shown) may be placed between the window material and the processing chamber (5) to block the window material and the processing chamber (5), so that the window material is not exposed to plasma during plasma processing.

[0102] In addition, the incident infrared (IR) is continuous light parallelized by the optical system, or 1300 cm -1 , 1800cm -1and a monochromatic laser with a wavenumber between them, for example, 3 wavenumbers or higher such as 1592 cm⁻¹, may be used. Incident infrared (IR) is irradiated onto the film (24) on the upper surface of the earth electrode (22). Infrared (SL) scattered from the earth electrode (22) passes through the window material of the window (43) to the IR detector (41) (e.g., triglyceride deuterium sulfate, D euterated T ri G lycine S ulfate: Detected by DTGS detector.

[0103] The inspection device (30), as in Example 1, detects the minimum peak intensity of the absorption intensity for the detected infrared (SL). For example, the background is 1300 cm -1 Wow, 1800cm -1 It is interpolated using the absorption intensity of infrared radiation from a monochromatic laser with the wavenumber of . In addition, 1592 cm⁻¹ as infrared radiation of a predetermined frequency -1 Measure the infrared absorption intensity of a monochromatic laser with the wavenumber of and differ the interpolated background. Normalized lifetime and 1592 cm -1 The correlation of peak intensity is the same as the correlation shown in Figure 8.

[0104] (Actions / Effects)

[0105] By configuring as described above, the evaluation of the components in the processing chamber (5) can be performed without breaking the vacuum vessel of the plasma processing device (200).

[0106] (Example 3)

[0107] Example 3 is described using FIG. 17. FIG. 17 is a schematic diagram showing the case where the earth electrode (22) is removed after the vacuum of the processing chamber of the plasma processing device is broken and the absorption intensity of infrared rays is measured. FIG. 17 (a) is a perspective view and FIG. 17 (b) is a cross-sectional view.

[0108] In Example 3, the spectrum of infrared intensity reflected and scattered from the surface of the film (24) is measured using a Fourier transform infrared absorption spectrometer (29) without contacting the film (24) of the earth electrode (22). In Example 1, as shown in FIG. 2, infrared rays are irradiated onto the earth electrode (22) while the Fourier transform infrared absorption spectrometer (29) is positioned on a movable arm. Meanwhile, in Example 3, as shown in FIG. 17, the earth electrode (22) is positioned on a stand that is movable in the up, down, left, and right directions and in the rotational direction, and the absorption and scattering of infrared rays at multiple locations on the inner wall material of the earth electrode (22) are measured while the Fourier transform infrared absorption spectrometer (29) is fixed.

[0109] (Actions / Effects)

[0110] By doing this, it is possible to evaluate the deviation of the spectrum of infrared intensity within the earth electrode (22), and it is also possible to detect the location where the most deterioration has occurred within the earth electrode (22).

[0111] Although embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the essence of the present invention.

[0112] The embodiments that may constitute the content of the present invention are described below, but are not limited thereto.

[0113] (Sun 1)

[0114] A plasma processing apparatus having a member having a film containing Y and O installed on its surface within a processing chamber for processing wafers using plasma,

[0115] A plasma processing apparatus having a control unit that maintains the lifespan of the member, or that damage or consumption of the film has reached a certain value when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal.

[0116] (Sun 2)

[0117] The above control unit is,

[0118] When the lifespan of the above-mentioned member is expressed as the number of wafers that can be processed from the above-mentioned retention until the repair work of the above-mentioned film, the number according to the lifespan is set to be smaller than the number of wafers until it is determined that the absorption intensity value has become minimum, or

[0119] A plasma treatment apparatus described in Sun 1, wherein, when the above lifespan is represented as the total sum of the time during which the plasma can be formed from the above retention period until the repair work of the above film, the total sum of the time according to the above lifespan is set to be smaller than the total sum of the time during which the plasma is formed until it is determined that the absorption intensity value has become minimal.

[0120] (Sun 3)

[0121] The above control unit is,

[0122] When the lifespan of the above-mentioned member is expressed as the number of wafers that can be processed from the point in time when it is determined that the absorption intensity value has become minimum until the repair work of the coating, the number according to the lifespan is set to be smaller than the number of wafers until it is determined that the absorption intensity value has become minimum, or

[0123] A plasma treatment apparatus described in Sun 1 or 2, wherein, when the lifespan of the above-mentioned member is expressed as the total sum of the time during which the plasma can be formed from the point in time when it is determined that the absorption intensity value has become minimum until the repair work of the above-mentioned film, the total sum of the time according to the lifespan is set to be smaller than the total sum of the time during which the plasma is formed until it is determined that the absorption intensity value has become minimum.

[0124] (Sun 4)

[0125] The above control unit is a plasma treatment device described in any one of Solar 1 to Solar 3, which maintains the degree of damage or wear caused by a change in the composition of Y, O, and F included on the surface of the film after the absorption intensity value of the infrared radiation of the above predetermined wavelength becomes minimum.

[0126] (Sun 5)

[0127] The above predetermined wavelength is 1300 to 1850 cm -1 A plasma treatment device described in any one of Sun 1 to Sun 4, which is the wavelength at which the absorption intensity value is maximized within the range.

[0128] (Sun 6)

[0129] A first window for irradiating infrared rays onto the member disposed within the processing room, and

[0130] A second window that emits infrared rays scattered from the above member out of the processing room, and

[0131] A plasma processing device described in any one of Sun 1 to Sun 5, further comprising a detector for detecting infrared rays emitted from the second window.

[0132] (Sun 7)

[0133] A method of operating a plasma processing apparatus having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, wherein

[0134] A method of operating a plasma treatment apparatus including a treatment that preserves the lifespan of the member, wherein when the absorption intensity value of infrared rays of a predetermined wavelength detected from the surface of the film of the member becomes minimal, the damage or consumption of the film reaches a certain value.

[0135] (Sun 8)

[0136] An inspection device for a plasma processing apparatus having a member having a film containing Y and O installed on its surface within a processing chamber for processing wafers using plasma,

[0137] The above inspection device is,

[0138] memory and,

[0139] Includes a processor,

[0140] The above memory is,

[0141] An inspection device comprising a processing command to execute the processor to ensure that damage or consumption of the film reaches a certain value or to preserve the lifespan of the member when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal.

[0142] (Sun 9)

[0143] A method for inspecting a plasma processing device having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, wherein the inspection device comprises:

[0144] The usage period elapsed after the above component is placed in the above processing room is measured, and

[0145] The infrared reflection intensity is measured for the above member, and

[0146] Interpolating the background in a specific wavelength region among the above-measured infrared absorption intensities, and

[0147] By taking the difference of the interpolated background above, the peak intensity of the infrared absorption intensity is detected, and

[0148] An inspection method comprising a process for detecting the minimum of the peak intensity. Explanation of the symbols

[0149] 1… Shower plate, 2… Window member, 3… Wafer, 4… Stage, 5… Processing chamber, 6… Gap, 7… Through hole, 8… Exhaust piping, 9… Dry pump, 10… Turbo molecular pump, 11… Impedance matcher, 12… High-frequency power supply, 13… Plasma, 14… Pressure regulating plate, 15… Valve, 16… Valve, 17… Valve, 18… Magnetron oscillator, 19… Waveguide, 20… Solenoid coil, 21… Solenoid coil, 22… Earth electrode, 23… Base material, 24… Coating, 25… Processing gas supply piping, 26… Valve, 27… Pressure detector, 28… Substrate, 40… IR laser light source, 41… IR detector, 42… Window, 43… Window, 50… Processing unit, 51… Memory, 52… Communication device, 53… Input / Output device, 54… Processor, 56… Protection unit, 100, 200… Plasma processing unit, 511… Spectrum measurement unit, 512… Background interpolation unit, 513… Background difference unit, 514… Service life measurement unit, 515… Life determination unit, 516… Protection unit, 517… FT-IR database, 518… Component database

Claims

Claim 1 A plasma processing apparatus having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, and a control unit having a control unit that reports that damage or consumption of the film has reached a certain value or that the lifespan of the member has been maintained when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal. Claim 2 A plasma processing apparatus according to claim 1, wherein the control unit, when the lifespan of the member is represented as the number of wafers that can be processed from the member until the repair work of the film, sets the number according to the lifespan to be smaller than the number of wafers until it is determined that the absorption intensity value has become minimum, or when the lifespan is represented as the total sum of the time during which the plasma can be formed from the member until the repair work of the film, sets the total sum of the time according to the lifespan to be smaller than the total sum of the time during which the plasma is formed until it is determined that the absorption intensity value has become minimum. Claim 3 A plasma processing apparatus according to claim 1, wherein the control unit, when the lifespan of the member is represented as the number of wafers that can be processed from the point in time when it is determined that the absorption intensity value has become minimum until the repair work of the film, sets the number of wafers according to the lifespan to be smaller than the number of wafers until it is determined that the absorption intensity value has become minimum, or when the lifespan of the member is represented as the total sum of the time during which the plasma can be formed from the point in time when it is determined that the absorption intensity value has become minimum until the repair work of the film, sets the total sum of the time according to the lifespan to be smaller than the total sum of the time during which the plasma was formed until it is determined that the absorption intensity value has become minimum. Claim 4 A plasma treatment device according to claim 1, wherein the control unit maintains the degree of damage or consumption caused by a change in the composition of Y, O, and F included on the surface of the film after the absorption intensity value of the infrared radiation of the predetermined wavelength becomes minimal. Claim 5 In any one of claims 1 to 3, the predetermined wavelength is 1300 to 1850 cm -1 A plasma treatment device having a wavelength at which the absorption intensity value is maximized within the range. Claim 6 A plasma processing apparatus according to claim 1, further comprising: a first window for irradiating infrared rays onto a member disposed within the processing chamber; a second window for emitting infrared rays scattered from the member out of the processing chamber; and a detector for detecting infrared rays emitted from the second window. Claim 7 A method of operating a plasma processing apparatus having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, wherein when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal, the damage or consumption of the film reaches a certain value, or the method of operating the plasma processing apparatus includes a treatment to preserve the lifespan of the member. Claim 8 An inspection device for a plasma processing apparatus having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, wherein the inspection device comprises a memory and a processor, and the memory comprises a processing command to execute the processor to ensure that damage or consumption of the film reaches a certain value or to preserve the lifespan of the member when the absorption intensity value of infrared rays of a predetermined wavelength detected from the film surface of the member becomes minimal. Claim 9 A method for inspecting a plasma processing device having a member having a film containing Y and O installed on its surface within a processing chamber for processing a wafer using plasma, the method comprising measuring the usage period elapsed after the member is placed within the processing chamber, measuring the infrared reflection intensity of the member, interpolating a background in a specific wavelength region among the measured infrared absorption intensity, taking the difference of the interpolated background to detect the peak intensity of the infrared absorption intensity, and detecting the minimum of the peak intensity.

Images