Plasma-resistant laminate, its manufacturing method, and plasma processing apparatus

Abstract

To provide a capacitive probe-type plasma sensor including a plasma-resistant laminate.SOLUTION: A plasma-resistant laminate 1 comprises a substrate 2, a membrane electrode 3 formed on the substrate 2, and a dielectric layer 4 formed on the membrane electrode 3. The dielectric layer 4 is a polycrystalline dielectric layer and includes columnar particles longer in a thickness direction. The membrane electrode 3 is formed of active metal, or a constituent element of the substrate or the dielectric layer, or lamination of these elements.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a plasma-resistant laminate, a method for manufacturing the same, and a plasma processing apparatus. [Background technology]

[0002] In the field of semiconductor manufacturing, plasma processing methods using plasma discharge on a processing target such as a semiconductor substrate are widely used for the purpose of plasma CVD (chemical vapor deposition), ashing, etching, sputtering, and other surface treatments.

[0003] In a plasma processing process, when a high voltage or a high frequency voltage from a high frequency power supply is applied, there is a problem that the stability of the plasma may be deteriorated, such as abnormal discharge, which may cause deterioration of the characteristics of electronic elements in the object to be processed. To address such problems, it is necessary to accurately detect the plasma state in the plasma processing chamber.

[0004] Known plasma measuring instruments for detecting plasma states include the Langmuir probe, which inserts a probe-shaped electrode with an exposed tip into the plasma and measures plasma states such as space potential from the current-voltage characteristics obtained by applying a voltage, and the capacitance probe, which covers the electrode with an insulator and measures plasma states such as space potential from the electrostatic capacitance.

[0005] Conventionally proposed plasma measuring instruments include those disclosed in, for example, Patent Documents 1 to 3. That is, Patent Document 1 proposes a plasma monitoring device using a window-type probe. Patent Document 2 proposes a plasma processing device including a signal detection unit that detects a precursor signal to detect the occurrence of abnormal plasma discharge in advance, and a control unit that controls the ESC leakage current based on this precursor signal.

[0006] Patent Document 3 proposes that in a plasma processing apparatus, a probe base is installed on the side wall of the processing chamber, pulsed bias power is applied to this base, and the state of the inner wall of the processing chamber and the internal state of the plasma are monitored in real time by analyzing the voltage change of the capacitor, and the processing method of the plasma processing apparatus is controlled from the data values. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-318115 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-73309 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-228386 Summary of the Invention

[0008] The plasma-resistant laminate of the present disclosure comprises a substrate, a film electrode located on the substrate, and a dielectric layer located on the film electrode, wherein the dielectric layer is a polycrystalline dielectric layer and contains columnar particles that are long in the thickness direction, and the film electrode is made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof.

[0009] The method for manufacturing the plasma-resistant laminate of the present disclosure includes the steps of polishing the surface of a substrate to an arithmetic mean height (Sa) of 0.01 μm or less, forming a film electrode on the substrate, and forming a dielectric layer by repeatedly depositing and oxidizing a metal material.

[0010] The plasma processing apparatus of the present disclosure has a capacitive probe type plasma sensor including the above-described plasma-resistant laminate attached to a plasma processing chamber. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic cross-sectional view showing a plasma-resistant laminate according to an embodiment of the present disclosure. [Figure 2]FIG. 1 is a schematic diagram showing a sputtering apparatus for producing a plasma-resistant laminate. [Figure 3A] 1 is a laser microscope photograph (magnification: 1200 times) of a substrate on which a film is formed using sapphire. [Figure 3B] For comparison, this is a laser microscope photograph (magnification: 1200 times) of a substrate on which a film was formed using alumina. [Figure 4A] 1 is a scanning electron microscope (SEM) photograph showing the interface between the film electrode and the dielectric layer in the center. [Figure 4B] 1 is a scanning electron microscope (SEM) photograph showing the interface between the film electrode and the dielectric layer in the outer periphery. DETAILED DESCRIPTION OF THE INVENTION

[0012] A plasma-resistant laminate according to an embodiment of the present disclosure will be described below. Fig. 1 is a schematic cross-sectional view showing a plasma-resistant laminate 1 according to this embodiment. This plasma-resistant laminate 1 functions as a capacitive probe-type plasma sensor.

[0013] As shown in FIG. 1, the plasma-resistant laminate 1 includes a substrate 2, a membrane electrode 3 formed on the substrate 2, and a dielectric layer 4 formed on the membrane electrode 3.

[0014] The substrate 2 includes sapphire, and the dielectric layer 4 includes an oxide containing yttrium. Sapphire has excellent plasma resistance and mechanical strength. Furthermore, yttria (Y2O3), an oxide of yttrium, has even better plasma resistance than sapphire.

[0015] Furthermore, since sapphire is a single crystal, the surface can be processed to be smooth, allowing the formation of thin film electrodes 3 and dielectric layers 4 with few defects such as voids, and as a result, the electrostatic capacitance calculated from (area x dielectric constant / thickness) can be increased.

[0016] Average linear thermal expansion coefficient (10 -6 / K) is 7.2 for the yttria constituting the dielectric layer 4, whereas the sapphire constituting the substrate 2 is 7.7 in the direction parallel to the c-axis and 7.0 in the direction perpendicular to the c-axis. Therefore, the difference in thermal expansion between the dielectric layer 4 and the substrate 2 is small, making peeling and cracks due to thermal stress less likely to occur.

[0017] The film electrode 3 is made of an active metal, a constituent element of the substrate 2 or the dielectric layer 4, or a laminate thereof. Active metals are metals that bond more easily with oxygen atoms in the oxides that make up the substrate 2 than inactive metals such as copper, silver, and gold, resulting in stronger adhesion. Typical active metals include alkaline earth metals, rare earth metals, metals from Groups 4 to 6 of the periodic table, and metals from Groups 13 to 14. Titanium, zirconium, hafnium, vanadium, and chromium in particular have strong adhesion to sapphire, and their thermal expansion coefficients are relatively similar to that of sapphire. Yttrium is a constituent element of yttria that makes up the dielectric layer 4. By oxidizing the surface of yttrium, the dielectric layer 4 can be continuously formed, which is expected to improve adhesion to the dielectric layer 4. Aluminum is a constituent element of sapphire that makes up the substrate 2. Heat treatment can be used to diffuse aluminum atoms, which is expected to improve adhesion to the substrate 2. It is particularly preferable that the membrane electrode 3 is a laminate of an active metal formed on the substrate 2 and yttrium formed on the active metal, since this increases adhesion to both the substrate 2 and the dielectric layer 4.

[0018] The thickness of the membrane electrode 3 is 0.5 μm or more and 5 μm or less, and the thickness of the dielectric layer 4 from the surface of the membrane electrode 3 is 0.5 μm or more and 5 μm or less, and the area is 1000 mm 2 Since the film electrode 3 is thus thin, it can be covered with a thin dielectric layer 4, and the capacitance (area × dielectric constant / thickness) can be increased. Specifically, the plasma-resistant laminate of this embodiment preferably has a capacitance of 1 nF or more.

[0019] It is preferable that the surface of the substrate 2 be the c-plane of sapphire. The substrate 2 is thicker than the film electrode 3 and the dielectric layer 4, so deformation and stress of the substrate 2 have a large effect on deformation and stress of the plasma-resistant laminate 1. The c-plane has the advantage that it has no anisotropy in thermal expansion coefficient or Young's modulus, and therefore is less susceptible to deformation when the temperature changes.

[0020] Depending on the formation method, the dielectric layer 4 may have compressive stress in a direction perpendicular to the thickness direction. The direction perpendicular to the thickness direction is the direction parallel to the surface of the dielectric layer 4. For example, as will be described later, in the post-oxidation sputtering method, the oxide film (dielectric layer 4) is formed by repeatedly depositing and oxidizing a metal (yttrium), and the interatomic distance increases during oxidation. At this time, it is thought that compressive stress occurs in the dielectric layer 4 because the direction perpendicular to the thickness direction is constrained by the base 2.

[0021] The stress in the direction perpendicular to the thickness direction of the dielectric layer 4 can be measured using an X-ray diffraction device. Stress in two directions parallel to the surface and perpendicular to each other is evaluated at multiple points (e.g., five points) within the plane, and the respective average values ​​are defined as σ11 and σ22. Because the dielectric layer 4 is thin, cracks are likely to occur when tensile stress is applied in the direction perpendicular to the thickness direction. Therefore, it is preferable that σ1, which is the average value of stress σ11 and stress σ22, is compressive stress. In this case, it is particularly preferable that both σ11 and σ22 are compressive stress. Since distortion is also likely to occur when the difference between σ11 and σ22 is large, it is preferable that σ22 / σ11 is 0.5 to 2, preferably 0.8 to 1.2.

[0022] The average value σ1 of the stresses σ11 and σ22 may be 200 MPa or more and 1000 MPa or less. When σ1 is 200 MPa or more, hardness is maintained and the occurrence of particles, cracks, etc. can be reduced. On the other hand, when σ1 is too large, deformation and cracks are likely to occur and the bonding strength is likely to decrease, so σ1 is preferably 1000 MPa or less.

[0023] As described above, the thermal expansion coefficient of sapphire is larger than that of yttria in the direction parallel to the c-axis and smaller than that of yttria in the direction perpendicular to the c-axis. Therefore, σ1 can be adjusted by selecting the crystal orientation of the sapphire used as the substrate 2. For example, when σ1 is compressive stress as in the embodiment of the present invention, it is preferable to use sapphire with a surface perpendicular to the c-axis (c-plane) facing the dielectric 4 of the substrate 2 in an environment at a lower temperature than that during the deposition of the dielectric layer 4, because the difference in thermal expansion between the substrate 2 and the dielectric layer 4 alleviates σ1 (prevents σ1 from becoming too large). Furthermore, for example, when the shape of the substrate 2 is rectangular and has a long (long side) direction and a short (short side) direction, causing a difference between σ11 and σ22, the surface of the substrate 2 facing the dielectric 4 may be made of sapphire with a plane parallel to the c-axis (a-plane, m-plane, etc.), and the orientation of the sapphire may be selected so that the direction that is likely to cause large compressive stress (for example, the long side of the rectangle) is perpendicular to the c-axis. Perpendicular to or parallel to the c-axis does not need to be completely perpendicular or parallel, and may be within ±15°, for example.

[0024] Furthermore, the dielectric layer 4 is preferably formed of columnar grains that are long in the thickness direction. It is particularly preferable that the length of the grains in the thickness direction is approximately the same as the thickness of the dielectric layer 4. The average grain size on the surface of the dielectric layer 4 is preferably 0.01 μm to 0.5 μm, and the average aspect ratio of the grains (major axis / minor axis) is preferably 2 or more. If the average grain size is 0.01 μm or more on the surface of the dielectric layer 4 that is most exposed to plasma, the proportion of grain boundaries decreases, improving plasma resistance. Furthermore, columnar grains that are long in the thickness direction reduce the number of grain boundaries that cross the electric field direction, improving measurement accuracy. This results in high dielectric performance and plasma resistance. The dielectric layer 4 made of columnar grains can be formed using, for example, a post-oxidation sputtering device. The average particle size of the particles can be determined by using a scanning electron microscope (SEM) or the like to obtain a surface observation image of an area of, for example, 9 × 12 μm, drawing six straight lines of the same length, for example, 6 μm, radially from an arbitrary point as the center, and dividing the total length of these six straight lines by the total number of crystals present on these lines.

[0025] Furthermore, when observing a cross section cut along the thickness direction, the dielectric layer 4 may have elongated pores whose length in the thickness direction is longer than the length in the direction perpendicular to the thickness direction. When the dielectric layer 4 has such elongated pores, the area ratio of the pores when viewed in the thickness direction can be reduced, thereby minimizing the decrease in capacitance due to the pores and improving measurement accuracy. Furthermore, the capacitance of the dielectric layer 4 in the thickness direction can be appropriately maintained to improve measurement accuracy, while the stress generated in the dielectric layer 4 can be effectively alleviated by the pores. The dielectric layer 4 having elongated pores in the thickness direction can be formed by repeating film formation multiple times using, for example, a post-oxidation sputtering apparatus. The area ratio of the pores in the cross section cut along the thickness direction of the dielectric layer 4 having elongated pores may be 0.05 area % to 8 area %.

[0026] The plasma generating unit generates light of various wavelengths. Light with wavelengths of 400 nm or less is called ultraviolet light, and light with wavelengths of 700 nm or more is called infrared light. When infrared light is absorbed by a substance, it generates heat (increased lattice vibration). Heating the dielectric layer 4 raises concerns that the characteristics of devices using the dielectric layer 4 may change due to changes in resistivity caused by the thermal generation of carriers (electrons). Ultraviolet light can also cause deterioration of various materials, such as polymers. When the dielectric layer 4 absorbs ultraviolet light, some of it is converted to light of a different wavelength, reducing the reflection and transmission of ultraviolet light. This reduces the impact of ultraviolet light on surrounding components compared to when the reflectance of ultraviolet light is high. Therefore, the dielectric layer 4 should have a reflectance of 50% or less, preferably 30% or more, for light with wavelengths of 400 nm or less. The dielectric layer 4 should also have a reflectance of 50% or more, preferably 60% or more, for light with wavelengths of 700 nm or more. If the reflectance for light with a wavelength of 400 nm or less is 50% or less, preferably 30% or more, the reflectance for ultraviolet light is low, thereby reducing the deterioration of other components exposed to plasma light inside and outside the device, particularly organic components that are susceptible to deterioration by ultraviolet light.If the reflectance for light with a wavelength of 700 nm or more is 50% or more, preferably 60% or more, the reflectance for infrared light is high, thereby suppressing the temperature rise on the film surface and reducing the change in element sensitivity due to plasma exposure.

[0027] As shown in FIG. 1, the substrate 2 is formed on the surface of a support layer 5. For example, alumina ceramic can be used as the support layer 5. Since alumina ceramic is the same material as sapphire, the difference in physical properties such as the coefficient of thermal expansion is small, and it can be produced more cheaply than sapphire. The substrate 2 and the support layer 5 can be bonded together using, for example, an epoxy adhesive or a silicone adhesive, or directly bonded by diffusion bonding or the like. A power supply terminal 7 for power supply and measurement is provided on the support layer 5. The support layer 5 may be provided if necessary, or the substrate 2 and support layer 5 may be formed integrally using sapphire.

[0028] The substrate 2 has a plurality of via electrodes 6 electrically connected to the membrane electrodes 3. The via electrodes 6 can be formed by copper plating or the like in through holes provided in the substrate 2. The diameter of the via electrodes 6 is preferably 30 μm or more and 200 μm or less.

[0029] If there is a step between the via electrode 6 and the base 2, there is a risk that the electrical connection with the film electrode 3 may be impaired (disconnected). Therefore, in this embodiment, it is preferable to adjust the step between the via electrode 6 and the base 2 by surface polishing to 1.0 μm or less, preferably 0.2 μm or less. This makes it possible to maintain the surface smoothness and the film thickness distribution of the dielectric layer 4 with very high precision without variation.

[0030] The membrane electrode 3 is electrically connected to a power supply terminal 7 of the support layer 5 through a via electrode 6. This allows the membrane electrode 3 to function as a probe for plasma measurement, enabling the measurement of the space potential that indicates the plasma state.

[0031] Next, a method for producing the plasma-resistant laminate of the present disclosure will be described. The plasma-resistant laminate of the present disclosure can be produced by the steps exemplified below. <Process for polishing the substrate 2> The surface of the substrate 2 containing sapphire is polished to an arithmetic mean height (Sa) of 0.1 μm or less, preferably 10 nm or less. The substrate 2 has the above-mentioned plurality of via electrodes 6 formed thereon in advance. The polishing may be performed, for example, by lapping using diamond abrasive grains and a surface plate, and chemical mechanical polishing (CMP) using colloidal silica abrasive grains and an alkaline slurry.

[0032] Arithmetic mean height (Sa) is a parameter of surface texture defined in ISO25178-6:2010, and is a parameter that extends the arithmetic mean roughness Ra of lines to surfaces. Specifically, arithmetic mean height (Sa) represents the average of the absolute values ​​of the difference in height of each point on the target surface relative to the average surface of the target surface. Sa represents the average of the absolute values ​​of the difference in height of each point on the target surface relative to the average surface of the target surface.

[0033] The substrate 2 includes single crystal sapphire. The surface of the substrate 2 is preferably the c-plane of sapphire in order to reduce the difference in thermal expansion with the dielectric layer 4. The thickness of the substrate 2 is designed so that the plasma-resistant laminate 1 satisfies the mechanical strength requirements, and for example, if the diameter of the substrate 2 is about 50 mm (2 inches), the thickness should be 100 μm or more.

[0034] <Step of forming the film electrode 3 and the dielectric layer 4> It is preferable to form a membrane electrode 3 having a thickness of 5 μm or less on a substrate 2, and then form a dielectric layer 4 having a thickness of 5 μm or less on the surface of this membrane electrode 3. The membrane electrode 3 is made of an active metal such as titanium or yttrium, or a constituent element of the substrate 2 or the dielectric layer 4, but the following explanation will be given taking the case where yttrium is used as an example.

[0035] A method for forming the film electrode 3 and the dielectric layer 4 will be described with reference to Fig. 2. Fig. 2 is a schematic diagram showing a sputtering apparatus 20, which includes a chamber 15, a gas supply source 13 connected to the inside of the chamber 15, an anode 14 and a cathode 12 located within the chamber 15, and a target 11 connected to the cathode 12 side.

[0036] The film electrode 3 and the dielectric layer 4 can be formed consecutively using a sputtering apparatus 20 capable of sputtering and plasma treatment. First, the substrate 2 obtained by the above-described method is placed on the anode 14 side in a chamber 15. A target 11 of metallic yttrium with a purity of 4N (99.99%) or higher is placed on the cathode 12 side on the opposite side of the chamber 15. In this state, the chamber 15 is depressurized using an exhaust pump, and argon and oxygen are supplied as gas G from a gas supply source 13. For example, the pressure of the argon gas is 0.1 Pa to 2 Pa, and the pressure of the oxygen gas is 1 Pa to 5 Pa. Here, to obtain a dielectric layer 4 in which the average value σ1 of the stresses σ11 and σ22 in two directions perpendicular to the thickness direction and orthogonal to each other is 200 MPa to 1000 MPa, the pressure of the argon gas should be 0.1 Pa to 1 Pa, and the pressure of the oxygen gas should be 1 Pa to 5 Pa.

[0037] Next, in an argon-rich atmosphere, an electric field is applied between the anode 14 and the cathode 12 by a power supply to generate plasma P, and sputtering is performed to form a metal yttrium film on the surface of the substrate 2, forming a film electrode 3 having a thickness of 5 μm or less. The power supplied from the power supply may be either high-frequency power or DC power. When forming a film electrode 3 in which multiple metals, such as titanium and yttrium, are stacked, multiple targets 11 may be placed in the sputtering apparatus 20, and the metal to be deposited may be switched by switching the target 11.

[0038] After forming the film electrode 3, the dielectric layer 4 is formed by a post-oxidation sputtering method. Specifically, a metal yttrium film is formed on the surface of the film electrode 3 by sputtering, followed by oxidation with oxygen plasma, to form a yttria film that becomes the dielectric layer 4. The thickness of each yttrium film formed is approximately 1 nm or less. The dielectric layer 4, containing yttria and having a thickness of 5 μm or less, is obtained by alternately forming the yttrium film and performing an oxidation process so that the total thickness of the dielectric layer 4 is 5 μm or less. In this way, the plasma-resistant laminate 1 of the present disclosure can be obtained. If the surface of the film electrode 3 is yttrium, the connection portion with the dielectric layer 4 can be formed by oxidizing the film electrode 3, resulting in a highly adhesive and stable dielectric layer 4. The interface between the yttrium layer and yttrium oxide is unclear, and there is a region where the oxygen ratio increases continuously.

[0039] The sputtering apparatus 20 for alternately performing the sputtering step of forming a metal yttrium film and the oxidation step can be classified into two types: one in which the sputtering region and the oxidation region are separated by a space and the substrate 2 moves between the two regions, and one in which the sputtering and oxidation are separated by a time and sputtering and oxidation are alternately performed in the same region. Figure 2 shows the latter type.

[0040] In the former type, a sputtering region and an oxidation region are set up inside the device, and the substrate 2 moves between these regions. Each region is surrounded by a partition wall, and in the sputtering region, the Ar partial pressure is increased, and ions are accelerated by a magnetic field (or electric field) to collide with the target. On the other hand, in the oxidation region, the oxygen partial pressure is increased.

[0041] In the latter type, the substrate 2 remains in the same place, and the gas species supplied into the chamber 15 are switched to repeat metal film deposition and oxidation.

[0042] In either case, in the sputtering region (during sputtering), argon-rich plasma is irradiated onto the target to perform sputtering, and in the oxidation region (during oxidation), oxygen-rich plasma is irradiated onto the substrate 2 and the film of the dielectric layer 4 to perform oxidation.

[0043] 1, the dielectric layer 4 is formed so as to cover the surface and side surfaces of the membrane electrode 3. The membrane electrode 3 is not exposed in this manner in order to protect the membrane electrode 3 from plasma.

[0044] Fig. 3A shows a laser microscope photograph (magnification: 1200x) of the surface of the dielectric layer 4 formed on the sapphire substrate 2. For comparison, Fig. 3B shows a laser microscope photograph (magnification: 1200x) of the surface of the dielectric layer 4 formed on an alumina ceramic substrate in a similar manner. The arithmetic mean height Sa of the sapphire substrate 2 after polishing was 10 nm or less, and the arithmetic mean height Sa of the alumina substrate was 30 nm or less.

[0045] Voids, scratches, etc. appear on the surface of the dielectric layer 4 of the alumina substrate shown in Figure 3B, whereas no voids, scratches, etc. are observed on the surface of the dielectric layer 4 of the sapphire substrate 2 shown in Figure 3A.

[0046] Furthermore, the surface of the dielectric layer 4 on the alumina substrate had an arithmetic mean height (Sa) of 0.199 μm, whereas the surface of the dielectric layer 4 on the sapphire substrate 2 had an arithmetic mean height (Sa) of 0.032 μm, making the surface smooth. Therefore, by using the sapphire substrate 2, it is possible to form a thin film electrode 3 and a dielectric layer 4 that are free of voids, etc.

[0047] 4A and 4B are scanning electron microscope (SEM) photographs showing an example of the laminated state of the formed film electrode 3 and dielectric layer 4, showing the interface portion at the center and the outer periphery, respectively. The plasma-resistant laminate 1 shown in Fig. 4A and 4B has a film electrode 3 made of yttrium (Y) with a thickness of about 2 µm formed on a substrate 2 made of sapphire, and a dielectric layer 4 made of yttria (YO) with a thickness of about 2 µm formed on the film electrode 3.

[0048] 4A and 4B show that the membrane electrode 3 and the dielectric layer 4 are laminated uniformly over the entire surface. In addition, an amorphous intermediate layer exists between the membrane electrode 3 made of yttrium and the dielectric layer 4 made of yttria. The intermediate layer has a composition intermediate between that of yttria and yttrium, and contributes to improving the adhesion between the membrane electrode 3 and the dielectric layer 4.

[0049] The support layer 5 may be bonded to the substrate 2 in advance of sputtering, or may be bonded after sputtering is completed.

[0050] The plasma-resistant laminate 1 of the present disclosure is used as a capacitive probe-type plasma sensor. That is, in a plasma processing apparatus that performs plasma processing on a workpiece such as a semiconductor substrate using plasma discharge, such as plasma CVD, ashing, etching, sputtering, etc., one or more of the plasma sensors are attached to the wall surface of the plasma processing chamber. Other uses of the plasma-resistant laminate 1 include an electrostatic chuck.

[0051] The plasma-resistant laminate 1 of this embodiment has excellent plasma resistance because the substrate 2 contains sapphire and the dielectric layer 4 contains yttrium oxide (yttria). Furthermore, because the difference in thermal expansion between sapphire and yttria is small, peeling or cracking due to thermal stress is unlikely to occur. Furthermore, sapphire also has excellent mechanical strength. Therefore, the plasma-resistant laminate 1 of this embodiment can be suitably used in a plasma measuring device in a plasma processing apparatus.

[0052] Although the embodiments of the present disclosure have been described above, the plasma-resistant laminate of the present disclosure is not limited to the above embodiments, and various modifications and improvements are possible within the scope of the present disclosure. For example, the substrate 2 may contain additives or oxygen defects in sapphire to adjust the light transmittance, or additives or defects that absorb harmful light, such as ultraviolet light, within a range that does not impair its properties. Furthermore, the dielectric layer 4 may contain other oxides, such as aluminum, in addition to yttrium, or may contain a composite oxide, such as yttrium aluminum garnet, within a range that does not impair its properties. [Explanation of symbols]

[0053] 1. Plasma-resistant laminate 2 Base 3 Membrane electrode 4 Dielectric Layer 5 Support layer 6 Via electrodes 7 Power supply terminal 11 Target 12 Cathode 13 Gas supply source 14 Anode 15 Chamber 20 Sputtering equipment

Claims

1. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; The plasma-resistant laminate, wherein the membrane electrode is a laminate of an active metal on the substrate and yttrium on the active metal.

2. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; The plasma-resistant laminate, wherein the film electrode is formed by laminating yttrium on titanium formed on the substrate.

3. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; the membrane electrode is made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof; A plasma-resistant laminate, wherein stresses σ11 and σ22 in two directions perpendicular to the thickness direction of the dielectric layer and perpendicular to each other are both compressive stresses, and σ22 / σ11 is 0.5 or more and 2 or less.

4. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; the membrane electrode is made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof; A plasma-resistant laminate, wherein the dielectric layer has a compressive stress in a direction perpendicular to the thickness direction, and the substrate surface is a c-plane of sapphire.

5. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; the membrane electrode is made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof; a plasma-resistant laminate, wherein the dielectric layer has a compressive stress in a direction perpendicular to a thickness direction, the shape of the substrate has a long direction and a short direction, the surface of the substrate is a plane parallel to a c-axis of sapphire, and the long direction is parallel to the c-axis of sapphire.

6. 6. The plasma-resistant laminate according to claim 1, wherein the columnar particles contain an oxide containing yttrium.

7. The membrane electrode has a thickness of 5 μm or less, and the dielectric layer has a thickness from the surface of the membrane electrode of 5 μm or less, area 1000 mm ２ The plasma-resistant laminate according to any one of claims 1 to 5.

8. 6. The plasma-resistant laminate according to claim 1, which has a capacitance of 1 nF or more.

9. 4. The plasma-resistant laminate according to claim 3, wherein the σ22 / σ11 is 0.8 or more and 1.2 or less.

10. 4. The plasma-resistant laminate according to claim 3, wherein an average value σ1 of stresses σ11 and σ22 in two directions perpendicular to the thickness direction of the dielectric layer and perpendicular to each other is a compressive stress of 200 MPa or more and 1000 MPa or less.

11. 6. The plasma-resistant laminate according to claim 1, wherein the substrate is a single crystal.

12. 6. The plasma-resistant laminate according to claim 1, wherein the substrate has a via electrode electrically connected to the membrane electrode, and a step between the via electrode and the substrate is 1.0 μm or less.

13. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; A method for producing a plasma-resistant laminate, wherein the film electrode is made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof, a step of polishing the surface of the substrate so that the arithmetic mean height (Sa) is 10 nm or less; forming the membrane electrode on the substrate; forming the dielectric layer by repeatedly depositing a metal material and oxidizing it; A method for manufacturing a plasma-resistant laminate, comprising:

14. The method for producing a plasma-resistant laminate according to claim 13, wherein the film electrode has a thickness of 5 μm or less, and the dielectric layer has a thickness of 5 μm or less.

15. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; A plasma processing apparatus in which a plasma sensor including a plasma-resistant laminate, the film electrode being made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof, is installed in a plasma processing chamber.

16. A plasma-resistant laminate comprising a substrate, a membrane electrode located on the substrate, and a dielectric layer located on the membrane electrode, the dielectric layer is a polycrystalline dielectric layer and contains columnar grains that are long in the thickness direction; The plasma-resistant laminate for a plasma sensor, wherein the film electrode is made of an active metal, or a constituent element of the substrate or the dielectric layer, or a laminate thereof.

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