Electrostatic chuck component and electrostatic chuck device

Abstract

This electrostatic chuck component is provided with: a base body, one main surface of which is a placement surface on which a plate-shaped sample is placed; and an electrostatic adsorption electrode provided on the opposite side of the mounting surface or inside the base body, the electrostatic adsorption electrode having, on the side peripheral surface of the base body continuous with the mounting surface, at least: a first curved surface that is a convex curved surface provided in the circumferential direction at the peripheral edge of the mounting surface; and a second curved surface that is provided in the circumferential direction at a position different from the first curved surface in height, and that has an electric field dispersion structure that disperses an electric field at the outer edge of the electrostatic adsorption electrode in the vicinity of the outer edge of the electrostatic adsorption electrode.

Description

Technical Field

[0001] The present invention relates to an electrostatic chuck component and an electrostatic chuck device.

[0002] This application claims priority based on Japanese Patent Application No. 2022-206687 filed on December 23, 2022, and incorporates its content herein by reference. Background Art

[0003] Conventionally, in a semiconductor manufacturing process for manufacturing semiconductor devices such as ICs, LSIs, and VLSIs, a plate-like specimen such as a silicon wafer is fixed to an electrostatic chuck component having an electrostatic chuck function by electrostatic adsorption and is subjected to a prescribed process. In such a process, for example, after fixing a silicon wafer using an electrostatic chuck device, an etching process or a film-forming process using plasma is performed on the silicon wafer.

[0004] In the manufacturing process as described above, when using an electrostatic chuck device, sometimes particulate foreign matter (hereinafter referred to as foreign matter particles) typified by wafer residues is generated in the electrostatic chuck component. Such foreign matter particles are charged in the semiconductor manufacturing device and adhere to the surface of the electrostatic chuck device. The electrostatic chuck device having charged foreign matter particles (charged foreign matter particles) may impair the plasma stability in the manufacturing process, resulting in a decrease in productivity. Also, sometimes due to foreign matter particles, abnormal discharge may occur in the plasma process, disrupting the stabilization of the plasma, thereby causing a decrease in the yield of components or insulation breakdown of the electrostatic chuck device.

[0005] In response to the above-described problems, in a semiconductor manufacturing process, the following treatment is performed: the electrostatic chuck device contaminated with foreign matter particles is subjected to plasma cleaning to remove the foreign matter particles (for example, refer to Patent Document 1).

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2013-512564 Summary of the Invention

[0009] Technical Problem to be Solved by the Invention

[0010] In recent years, in order to improve the yield of semiconductor chips obtained from silicon wafers, a plan has been proposed to expand the electrostatic adsorption electrodes provided in the electrostatic chuck component. In the electrostatic chuck component in which the electrostatic adsorption electrodes are expanded, the difference in adsorption force between the center and the periphery of the wafer placement surface becomes smaller, and even in the outer peripheral portion of the silicon wafer, the same processing (etching process) as in the central portion can be performed. As a result, even in the outer peripheral portion of the silicon wafer, semiconductor chips can be appropriately manufactured, thereby improving the yield.

[0011] On the other hand, if the electrostatic adsorption electrode is enlarged, the distance between the side surface of the electrostatic chuck member and the electrostatic adsorption electrode becomes closer, and the electric field strength on the side surface of the electrostatic chuck member increases. Therefore, in the electrostatic chuck member with the enlarged electrostatic adsorption electrode, compared with the conventional electrostatic chuck, it becomes a structure in which charged foreign particles are easily electrostatically adsorbed on the side surface.

[0012] In the electrostatic chuck member described in Patent Document 1, in order to improve the effect of plasma cleaning, an inclined portion is provided around it. However, although this structure can effectively perform cleaning before the wafer process, it cannot suppress the attachment of charged foreign particles to the side surface of the electrostatic chuck member during the manufacturing process. Therefore, there are problems such as a decrease in the yield (productivity decrease) of components caused by abnormal discharge occurring during the wafer process or insulation breakdown of the electrostatic chuck. Therefore, there is a need for an electrostatic chuck member that can reduce the influence of charged foreign particles attached to the side surface of the electrostatic chuck member even during the wafer process and suppress the occurrence of abnormal discharge.

[0013] The present invention has been completed in view of such circumstances, and its object is to provide an electrostatic chuck member that can solve the problems caused by the attachment of charged foreign particles to the side surface, and in particular, can reduce abnormal discharge occurring during the wafer process. Another object of the present invention is to provide an electrostatic chuck device having such an electrostatic chuck member.

[0014] Means for Solving Technical Problems

[0015] In order to solve the above problems, one aspect of the present invention includes the following aspects.

[0016] [1] An electrostatic chuck member having: a base body, one main surface of which is a placement surface for placing a plate-shaped specimen; and an electrostatic adsorption electrode provided on the side opposite to the placement surface or inside the base body. On the side peripheral surface of the base body continuous with the placement surface, it has at least: a first curved surface, which is a convex curved surface provided along the circumferential direction at the peripheral edge of the placement surface; and a second curved surface, which is provided along the circumferential direction at a height position different from the first curved surface, and has an electric field dispersion structure for dispersing the electric field at the outer edge of the electrostatic adsorption electrode near the outer edge of the electrostatic adsorption electrode.

[0017] [2] The electrostatic chuck member according to [1], wherein

[0018] The electric field dispersion structure is an electrode inclined surface provided at the outer edge portion of the electrostatic adsorption electrode, exposed to the view from the direction of the placement surface, and inclined.

[0019] [3] The electrostatic chuck member according to [2], wherein

[0020] The electrode inclined surface is a convex curved surface.

[0021] [4] The electrostatic chuck component according to any one of [1] to [3], wherein

[0022] The electric field dispersion structure is a low-density portion provided at the outer edge portion of the electrostatic adsorption electrode, and the relative density of the low-density portion is lower than the relative density at the center of the electrostatic adsorption electrode.

[0023] [5] The electrostatic chuck component according to any one of [1] to [4], wherein

[0024] The electric field dispersion structure is a gap provided between the outer edge of the electrostatic adsorption electrode and the inner edge of the base body.

[0025] [6] The electrostatic chuck component according to any one of [1] to [5], wherein

[0026] The side circumferential surface has a portion provided along the circumferential direction and extending outward at the lower end portion of the side circumferential surface, and the second curved surface is a concave curved surface provided on the upper surface of the extending portion.

[0027] [7] The electrostatic chuck component according to any one of [1] to [6], wherein

[0028] The width of the electric field dispersion structure is greater than the thickness of the electrostatic adsorption electrode.

[0029] [8] The electrostatic chuck component according to any one of [1] to [7], wherein

[0030] On the side circumferential surface, the inclined surface between the first curved surface and the second curved surface is a surface exposed to the field of view from the direction of the mounting surface.

[0031] [9] An electrostatic chuck device, comprising: the electrostatic chuck component according to any one of [1] to [8]; and a base component that cools the electrostatic chuck component and adjusts the temperature of the electrostatic chuck component.

[0032] Effect of the Invention

[0033] According to the present invention, it is possible to provide an electrostatic chuck component capable of reducing problems caused by attachment of charged foreign particles to the side surface. And, it is possible to provide an electrostatic chuck device having such an electrostatic chuck component. Brief Description of the Drawings

[0034] Figure 1 It is a schematic perspective view showing an example of the electrostatic chuck component 10 of the first embodiment.

[0035] Figure 2 is a schematic cross-sectional view showing an example of the electrostatic chuck member 10 of the first embodiment.

[0036] Figure 3A is a schematic cross-sectional view showing an example of the electrostatic chuck member 10 of the first embodiment.

[0037] Figure 3B is a schematic cross-sectional view showing an example of the electrostatic chuck member 10 of the first embodiment.

[0038] Figure 4 is a schematic explanatory view showing an example of a manufacturing method of the electrostatic chuck member 10 of the first embodiment.

[0039] Figure 5 is a schematic explanatory view showing an example of the electrostatic chuck member 20 according to the second embodiment.

[0040] Figure 6 is a schematic explanatory view showing an example of the electrostatic chuck member 30 according to the third embodiment.

[0041] Figure 7 is a schematic explanatory view of the electrostatic chuck member 40 according to a modified example of the third embodiment.

[0042] Figure 8 is a schematic explanatory view of the electrostatic chuck member 50 according to a modified example of the fourth embodiment.

[0043] Figure 9 is a schematic explanatory view of the electrostatic chuck member 60 according to a modified example of the fifth embodiment.

[0044] Figure 10 is a schematic explanatory view of the electrostatic chuck member 70 according to a modified example of the sixth embodiment.

[0045] Figure 11 is a schematic cross-sectional view showing an example of the electrostatic chuck device of the embodiment.

[0046] Figure 12 is a schematic explanatory view showing an example of a semiconductor manufacturing apparatus having the above-described electrostatic chuck device. Detailed Embodiment

[0047] [First Embodiment]

[0048] Hereinafter, with reference to Figures 1 to 4 an example of the electrostatic chuck member according to the first embodiment of the present invention will be described. In addition, in all the following drawings, the dimensions, ratios, etc. of each component are appropriately changed for easy observation of the drawings.

[0049] 《Electrostatic Chuck Member》

[0050] Figure 1 is a schematic perspective view of the electrostatic chuck component 10 of the present embodiment. Figure 2 , FIG. 3 is a cross-sectional view showing the electrostatic chuck component 10 of the present embodiment, which is a cross-sectional view taken along the arrow direction of line II-II in [[ID=]16]Figure 1 .

[0051] As Figure 1 shown in FIGS. 2 to 3, the electrostatic chuck component 10 includes a pair of ceramic plates 11 and 12, and an electrostatic adsorption electrode 13 and an insulating layer 15 interposed between the pair of ceramic plates 11 and 12. In the following description, the electrostatic adsorption electrode will be simply referred to as the "electrode".

[0052] The structure formed by combining the pair of ceramic plates 11 and 12 and the insulating layer 15 corresponds to the substrate in the present invention. One main surface of the substrate is a mounting surface 10x for mounting plate-shaped specimens.

[0053] In the following description, the relative positions between components may be described based on the XY axes in which the plane direction of the mounting surface 10x is set as the X direction and the normal direction of the mounting surface 10x is set as the Y direction. Also, on the Y axis, the side of the electrostatic chuck component 10 where the mounting surface 10x is located may be referred to as "upper", and the side opposite to the mounting surface 10x of the electrostatic chuck component 10 may be referred to as "lower" to describe the relative positions between components.

[0054] Figure 2 , the cross-sectional view shown in FIG. 3 is a cross-section obtained by cutting the electrostatic chuck component with a virtual plane including the center of the circle that is the smallest circle circumscribing the electrostatic chuck component 10 when viewed from above. In other words, Figure 2 , FIG. 3 is a cross-sectional view of a cross-section passing through the center C of the substrate (mounting surface 10x) and including the normal N of the substrate (mounting surface 10x). When the electrostatic chuck component 10 is substantially circular when viewed from above, the center of the above-mentioned circle is substantially coincident with the center of the shape of the electrostatic chuck component when viewed from above.

[0055] In addition, in this specification, "viewed from above" means the field of view observed from the thickness direction of the electrostatic chuck component, that is, the Y direction, or the field of view observed from the direction of the mounting surface 10x.

[0056] And "cross-sectional view" means the field of view in the direction orthogonal to the cross-section when cutting along a virtual plane perpendicular to the mounting surface and including the center of the circle when assuming the smallest circle circumscribing the electrostatic chuck component when viewed from above.

[0057] Moreover, when viewed from above, the side relatively closer to the center C may sometimes be referred to as "inner", and the side farther from the center C may be referred to as "outer".

[0058] Moreover, the so-called "outer edge" of the electrode 13 refers to the outer peripheral portion of the electrode 13 when viewed from above, and the so-called "outer edge portion" of the electrode 13 refers to the area near the outer edge facing the inside of the electrode 13.

[0059] In the ceramic plate 11, a ring-shaped protrusion portion with a quadrilateral cross-section that extends along the peripheral portion of the mounting surface 10x and surrounds the peripheral portion once may also be provided to prevent leakage of cooling gases such as helium (He).

[0060] In addition, in an electrostatic chuck member having minute protrusions on one main surface of the base, the virtual surface that contacts the tops of the respective minute protrusions is defined as the mounting surface 10x. And when the thus-defined virtual surface is a concave surface or a convex surface, the least-squares plane of the virtual surface is defined as the mounting surface 10x.

[0061] In the electrostatic chuck member 10, the electrode 13 is provided inside the base, but is not limited thereto. In the electrostatic chuck member, the electrode 13 may also be provided on the side opposite to the mounting surface 10x.

[0062] In the electrostatic chuck member 10, a ceramic plate 11, an electrode 13, an insulating layer 15, and a ceramic plate 12 are laminated in sequence. That is, the electrostatic chuck member 10 is an integrated body formed by bonding the ceramic plate 11 and the ceramic plate 12 via the electrode 13 and the insulating layer 15. And the electrode 13 and the insulating layer 15 are provided in such a manner as to contact the bonding surface facing the ceramic plate 12 in the ceramic plate 11 and the bonding surface facing the ceramic plate 11 in the ceramic plate 12.

[0063] (Ceramic plate)

[0064] The ceramic plates 11 and 12 have the same outer peripheral shape when viewed from above.

[0065] The ceramic plates 11 and 12 have the same composition or the same main components. The ceramic plates 11 and 12 may be made of an insulating material, or may be made of a composite of an insulating material and a conductive material.

[0066] The insulating material contained in the ceramic plates 11 and 12 is not particularly limited, but examples thereof include alumina (Al2O3), aluminum nitride (AlN), yttrium oxide (Y2O3), yttrium aluminum garnet (YAG), etc. Among them, Al2O3 and AlN are preferred.

[0067] The conductive material contained in the ceramic plates 11 and 12 is not particularly limited, but examples thereof include silicon carbide (SiC), titanium oxide (TiO2), titanium nitride (TiN), titanium carbide (TiC), carbon materials, rare earth oxides, rare earth fluorides, etc. As the carbon material, carbon nanotubes (CNT) and carbon nanofibers can be cited. Among them, SiC is preferred.

[0068] The material of the ceramic plates 11 and 12 is as long as the volume resistivity is 10 13 Ω·cm or more and 10 17 The material is not particularly limited to a material having a resistance of approximately Ω·cm or less, mechanical strength, and durability against corrosive gases and plasmas. Examples of such materials include Al2O3 sintered bodies, AlN sintered bodies, and Al2O3-SiC composite sintered bodies. From the perspectives of high-temperature dielectric properties, high corrosion resistance, plasma resistance, and heat resistance, the material for ceramic plates 11 and 12 is preferably an Al2O3-SiC composite sintered body.

[0069] The average primary particle size of the insulating material constituting the ceramic plates 11 and 12 is preferably 0.5 μm to 3.0 μm, more preferably 0.7 μm to 2.0 μm, and even more preferably 1.0 μm to 2.0 μm.

[0070] When the average primary particle size of the insulating material constituting the ceramic plates 11 and 12 is 0.5 μm or more and 3.0 μm or less, dense ceramic plates 11 and 12 having high withstand voltage and high durability can be obtained.

[0071] The average primary particle size of the insulating material constituting ceramic plates 11 and 12 is measured as follows: a cross-section of the ceramic plates 11 and 12 cut in the thickness direction is observed at 10,000 times magnification using a field emission scanning electron microscope (FE-SEM, manufactured by JEOL Ltd., JSM-7800F-Prime), and the average of the diameters of 200 insulating material particles is determined by the intercept method as the average primary particle size.

[0072] (Electrode for electrostatic adsorption)

[0073] Electrode 13 generates an electric charge and secures the plate-shaped sample using electrostatic attraction. Electrode 13 is a thin electrode with a greater width in a direction perpendicular to the thickness direction than in the thickness direction. Electrode 13 is formed by applying and sintering a slurry for forming an electrode layer. The thickness of the resulting electrode 13 can be controlled by determining the relationship between the applied thickness of the slurry and the resulting thickness of the electrode 13 through preliminary experiments, and then adjusting the applied thickness of the slurry accordingly.

[0074] The electrode 13 is composed of a sintered body of particles of a conductive material, or a composite body (sintered body) of particles of an insulating ceramic and particles of a conductive material.

[0075] When the electrode 13 is composed of insulating ceramic and conductive material, the volume resistivity of these mixed materials is preferably 10 -6 Ω·cm or more and 10-2 Below about Ω·cm.

[0076] When the electrode 13 is composed of a composite of an insulating ceramic and a conductive material, in the electrode 13, the content of the conductive material is preferably 15% by mass or more and 100% by mass or less, more preferably 20% by mass or more and 100% by mass or less. If the content of the conductive material is at least the above lower limit value, sufficient dielectric properties can be exhibited to the ceramic plate 12.

[0077] The conductive material contained in the electrode 13 can be a conductive ceramic, or a conductive material such as a metal or a carbon material. The conductive material contained in the electrode 13 is preferably at least one selected from the group consisting of SiC, TiO2, TiN, TiC, tungsten (W), tungsten carbide (WC), molybdenum (Mo), molybdenum carbide (Mo2C), tantalum (Ta), tantalum carbide (TaC, Ta4C5), carbon materials, and conductive composite sintered bodies.

[0078] Examples of the carbon material include carbon black, carbon nanotubes, carbon nanofibers, etc.

[0079] Examples of the conductive composite sintered body include Al2O3-Ta4C5, Al2O3-W, Al2O3-SiC, AlN-W, AlN-Ta, etc.

[0080] By the conductive material contained in the electrode 13 being at least one selected from the group consisting of the above substances, the conductivity of the electrode can be ensured.

[0081] The insulating ceramic contained in the electrode 13 is not particularly limited. For example, it is preferably at least one selected from the group consisting of Al2O3, AlN, silicon nitride (Si3N4), Y2O3, YAG, samarium-aluminum oxide (SmAlO3), magnesium oxide (MgO), and silicon dioxide (SiO2).

[0082] By the electrode 13 being formed of a conductive material and an insulating material, the bonding strength between the ceramic plates 11 and 12 and the electrode 13 is improved. And by the electrode 13 being formed of a conductive material and an insulating material, the mechanical strength as an electrode becomes stronger.

[0083] By the insulating material contained in the electrode 13 being Al2O3, the dielectric properties, high corrosion resistance, plasma resistance, and heat resistance at high temperatures can be maintained.

[0084] The ratio (mixing ratio) of the content of the conductive material and the insulating material in the electrode 13 is not particularly limited and can be appropriately adjusted according to the use of the electrostatic chuck member 10.

[0085] An electrode inclined surface 13A that is exposed in the field of view from the direction of the mounting surface and is inclined is provided at the outer edge portion of the electrode 13. The electrode inclined surface 13A corresponds to the "electric field dispersion structure" in the present invention. In addition, being exposed in the field of view from the direction of the mounting surface and being inclined does not mean being exposed in space, but means being recognized as a surface rather than a line in a top view.

[0086] (Insulating layer)

[0087] The insulating layer 15 is a structure provided for joining the ceramic plates 11 and 12 to each other between the ceramic plates 11 and 12 and at positions other than the portion where the electrode 13 is formed. The insulating layer 15 is disposed around the electrode 13 in a top view between the ceramic plates 11 and 12 (between a pair of ceramic plates).

[0088] The shape of the insulating layer 15 (the shape when the insulating layer 15 is viewed from above) is not particularly limited and can be appropriately adjusted according to the shape of the electrode 13. In Figure 2 it, the surface 15A of the insulating layer 15 that contacts the electrode 13 is shown as having an inclined surface with an inclination complementary to that of the electrode inclined surface 13A. The thickness (width in the Y direction) of the insulating layer 15 is equal to the thickness of the electrode 13.

[0089] The insulating layer 15 can be composed of an insulating material or a composite of an insulating material and a conductive material. The volume resistivity of the insulating layer 15 is 10 13 Ω·cm or more and 10 17 Ω·cm or less.

[0090] The insulating material constituting the insulating layer 15 is not particularly limited, but is preferably the same as the main components of the ceramic plates 11 and 12. The insulating material constituting the insulating layer 15 is preferably at least one selected from the group consisting of Al2O3, AlN, Si3N4, Y2O3, YAG, SmAlO3, MgO, and SiO2, for example. The insulating material constituting the insulating layer 15 is preferably Al2O3. By using Al2O3 as the insulating material constituting the insulating layer 15, the dielectric properties, high corrosion resistance, plasma resistance, and heat resistance at high temperatures can be maintained.

[0091] The conductive material constituting the insulating layer 15 is not particularly limited, but is preferably the same as the main components of the ceramic plates 11 and 12. The conductive material constituting the insulating layer 15 is preferably at least one selected from the group consisting of SiC, TiO2, TiN, TiC, W, WC, Mo, Mo2C, and carbon materials, for example. As the carbon material, carbon nanotubes, carbon nanofibers, etc. can be cited, for example. The conductive material constituting the insulating layer 15 is preferably SiC.

[0092] In the insulating layer 15, the content of the insulating material is preferably 80% by mass or more and 96% by mass or less, more preferably 80% by mass or more and 95% by mass or less, and still more preferably 85% by mass or more and 95% by mass or less. If the content of the insulating material is at least the above lower limit value, sufficient dielectric breakdown voltage resistance can be obtained. If the content of the insulating material is at most the above upper limit value, the charge removal effect of the conductive material contained in the insulating layer 15 can be sufficiently exhibited.

[0093] In the insulating layer 15, the content of the conductive material is preferably 4% by mass or more and 20% by mass or less, more preferably 5% by mass or more and 20% by mass or less, and still more preferably 5% by mass or more and 15% by mass or less. If the content of the conductive material is at least the above lower limit value, the charge removal effect of the conductive material can be sufficiently exhibited. If the content of the conductive material is at most the above upper limit value, sufficient dielectric breakdown voltage resistance can be obtained.

[0094] The average primary particle diameter of the insulating material constituting the insulating layer 15 is preferably 0.5 μm or more and 3.0 μm or less, and more preferably 0.7 μm or more and 2.0 μm or less.

[0095] If the average primary particle diameter of the insulating material constituting the insulating layer 15 is 0.5 μm or more, sufficient dielectric breakdown voltage resistance can be obtained. On the other hand, if the average primary particle diameter of the insulating material constituting the insulating layer 15 is 3.0 μm or less, processing such as grinding is easy.

[0096] The average primary particle diameter of the conductive material constituting the insulating layer 15 is preferably 0.1 μm or more and 1.0 μm or less, and more preferably 0.1 μm or more and 0.8 μm or less.

[0097] If the average primary particle diameter of the conductive material constituting the insulating layer 15 is 0.1 μm or more, sufficient dielectric breakdown voltage resistance can be obtained. On the other hand, if the average primary particle diameter of the conductive material constituting the insulating layer 15 is 1.0 μm or less, processing such as grinding is easy.

[0098] The method for measuring the average primary particle diameter of the insulating material and the average primary particle diameter of the conductive material constituting the insulating layer 15 is the same as the method for measuring the average primary particle diameter of the insulating material and the average primary particle diameter of the conductive material constituting the ceramic plates 11 and 12.

[0099] The insulating layer 15 may be provided separately from the ceramic plates 11 and 12, or may be formed integrally with either one of the ceramic plates 11 and 12 and then joined to the other ceramic plate.

[0100] In this specification, the so-called "formed integrally" means formed as one component (being one component). In this sense, the structure of "formed integrally with either one of the ceramic plates 11 and 12" is different from, for example, the structure in which the ceramic plates 11 and the insulating layer 15, which were originally two components, are "integrated" into one. The component formed by integrating the ceramic plate and the insulating layer can be formed by the following method: by grinding or polishing, a concave portion is formed on one surface of the ceramic plate (the ceramic plate without a concave portion) as the material.

[0101] Moreover, the insulating layer 15 can also be structured to be formed integrally with both of the ceramic plates 11 and 12.

[0102] The electrostatic chuck component formed integrally with both of the ceramic plates 11 and 12 and the insulating layer can be formed by the following method.

[0103] For example, using raw material powders of inorganic particles (for example, alumina powder or SiC powder) that are raw materials of the ceramic plates, a green compact before sintering having the same shape as the ceramic plates 11 and 12 is formed. After screen printing a conductive paste on one surface of the obtained green compact, another green compact is overlapped to form a laminate. Then, by hot pressing and sintering the laminate, an electrostatic chuck component formed integrally with both of the ceramic plates 11 and 12 and the insulating layer can be obtained.

[0104] The above-mentioned green compact can be formed by press molding or by flowing a slurry of the raw material powder into a molding die, or can also be formed by laminating green sheets after forming a thin green sheet using the raw material powder of the inorganic particles.

[0105] The thickness of the obtained electrode 13 can be controlled as follows: by previously obtaining the correspondence relationship between the coating thickness of the slurry for forming the electrode layer and the thickness of the obtained electrode 13 through preliminary experiments, the coating thickness of the slurry for forming the electrode layer is adjusted accordingly.

[0106] (Shape of the electrostatic chuck component)

[0107] In the following description, the thickness of the ceramic plate 11 is set as "thickness T1", the thickness of the ceramic plate 12 is set as "thickness T2", and the thickness of the electrode 13 is set as "thickness T3". Moreover, the distance in the X direction from the outer edge 13x of the electrode 13 to the side peripheral surface 10y is set as "width L1", and the distance in the X direction of the electrode inclined surface 13A is set as "width L2". Specifically, the width L2 means the distance in the X direction from the position (indicated by the reference numeral A) where the end portion in the X direction of the upper surface of the electrode 13 contacts the base body (ceramic plate 11) to the position (indicated by the reference numeral B) where the end portion in the X direction of the lower surface of the electrode 13 contacts the base body (ceramic plate 12). In Figure 2 it, the position B coincides with the outer edge 13x.

[0108] The thickness T1 of the ceramic plate 11 and the thickness T2 of the ceramic plate 12 can be appropriately set according to the performance of the electrostatic chuck device or semiconductor manufacturing device using the electrostatic chuck component 10. As an example, the thickness T1 is preferably 100 μm or more and 900 μm or less, more preferably 400 μm or more and 600 μm or less. Further, the thickness T2 varies greatly depending on the presence or absence of additional internal electrodes or heaters formed in the lower ceramic plate, and 0.9 mm or more and 4 mm or less are selected, etc., but are not limited to these.

[0109] The thickness T3 of the electrode 13 can be appropriately set according to the performance of the electrostatic chuck device or semiconductor manufacturing device using the electrostatic chuck component 10. As an example, the thickness T3 is preferably 5 μm or more and 40 μm or less, more preferably 10 μm or more and 20 μm or less.

[0110] On the side peripheral surface 10y of the base body of the electrostatic chuck component 10 that is continuous with the placement surface 10x, there are at least a first curved surface CS1 provided along the circumferential direction at the peripheral edge of the placement surface 10x and a second curved surface CS2 provided along the circumferential direction at a height position different from the first curved surface CS1. Both the first curved surface CS1 and the second curved surface CS2 of the electrostatic chuck component 10 are convex curved surfaces.

[0111] Moreover, on the side peripheral surface 10y of the electrostatic chuck component 10, between the first curved surface CS1 and the second curved surface CS2 is an inclined surface 10a that is exposed to the field of view from the direction of the placement surface 10x. That is, the side peripheral surface 10y includes the first curved surface CS1, the inclined surface 10a, and the second curved surface CS2 in order from the placement surface 10x side.

[0112] In this specification, the so-called "convex curved surface" means a curved surface that protrudes in the +y direction in a cross-section of the side peripheral surface.

[0113] On the other hand, the so-called "inclined surface" means a surface with a constant inclination in a cross-section of the side peripheral surface.

[0114] The inclined surface 10a is a surface obtained by linearly chamfering the corner along the virtual surface S1 and the virtual surface S2. Moreover, at both ends of the inclined surface 10a in the Figure 2 field of view, the two new corners generated by the chamfering are processed into the first curved surface CS1 and the second curved surface CS2 that are convex curved surfaces (convex curved surfaces) protruding outward.

[0115] The radius of curvature r1 of the first curved surface CS1 and the radius of curvature r2 of the second curved surface CS2 are preferably each greater than or equal to the thickness T3 of the electrode 13. By making the radii of curvature of the first curved surface CS1 and the second curved surface CS2 greater than the thickness T3 of the electrode 13, it is possible to suppress the concentration of the electric field on the first curved surface CS1 and the second curved surface CS2 during plasma processing, and it is possible to suppress the concentrated fixation of charged foreign particles in a specific portion (for example, a corner).

[0116] In addition, the radii of curvature of the first curved surface CS1 and the second curved surface CS2 are related to the shape formed as a result of polishing and grinding the base of the electrostatic chuck member 10. In the conductive material and the insulating material constituting the base, even if particles having a particle size larger than the radii of curvature of the first curved surface CS1 and the second curved surface CS2 are contained and the particles are disposed on the first curved surface CS1 or the second curved surface CS2, the shape or particle size of these particles will change due to polishing and grinding. Therefore, the radii of curvature of the first curved surface CS1 and the second curved surface CS2 do not depend on the particle size of the base material.

[0117] The radius of curvature r1 of the first curved surface CS1 and the radius of curvature r2 of the second curved surface CS2 are obtained by the following method.

[0118] First, for the portion (convex curved surface) of the electrostatic chuck member to be measured, when assuming the smallest circle circumscribing the electrostatic chuck member in a plan view, a virtual plane perpendicular to the mounting surface and including the center of the circle is used for cutting. The cross-section can be ground with an abrasive stone of #1000 or higher.

[0119] Next, a magnified photograph of the obtained cross-section is taken. The magnification factor is set according to the size of the convex curved surface to be measured by observing the convex curved surface using a stereoscope. The magnification factor is a factor that enables the radius of curvature to be appropriately measured from the obtained photograph, and is appropriately selected from the range of 40 times to 200 times, for example.

[0120] The radii of curvature r1 and r2 of the convex curved surface are measured from the obtained magnified photograph.

[0121] The above measurement method is also used when measuring the radius of curvature of the concave curved surface described later.

[0122] The electrostatic chuck member 10 may form the first curved surface CS1 and the second curved surface CS2 in a part of the circumferential direction of the side circumferential surface 10y, or may form the first curved surface CS1 and the second curved surface CS2 in the entire circumferential direction. Moreover, the curvatures of the first curved surface CS1 and the second curved surface CS2 may be constant in the circumferential direction or may be different in the circumferential direction.

[0123] It is considered that the amount of charged foreign particles attached to the side peripheral surface 10y increases as the electrode 13 is enlarged and the distance (width L1) in the X direction from the outer edge 13x of the electrode 13 to the side peripheral surface 10y becomes shorter. Due to the enlargement of the electrode 13 in recent years, it is required that the width L1 be set to 1 mm or less (1000 μm or less).

[0124] Moreover, in relation to the thickness T1 of the ceramic plate 11, it is required that the width L1 be set to 2 times or less of the thickness T1 (L1 / T1 ≤ 2). Thus, by making the width L1 smaller, charged foreign particles are likely to attach to the side peripheral surface 10y.

[0125] From this point of view, the inventors et al. have studied the structure of the electrostatic chuck member, and as a result, it is considered that by adopting a structure that suppresses the concentration of the electrostatic field that is the cause of the attachment of charged foreign particles, the attachment of charged foreign particles to the side peripheral surface 10y can be suppressed.

[0126] In the conventional electrostatic chuck member, corners are formed at the upper part of its side peripheral surface. And, as in the electrostatic chuck member described in Patent Document 1, when the upper part of the side peripheral surface is chamfered, two corners are formed on the side peripheral surface. Such a corner has, for example, a point (vertex) where two straight lines (surfaces of the plane) are in contact when observed from a cross section. On the other hand, the electrostatic field for adsorbing the plate-like specimen is likely to be concentrated at the corners of the side peripheral surface, and the charged foreign particles attracted by this electrostatic field are also likely to attach in a large amount and firmly in a narrow range around the corners of the side peripheral surface.

[0127] In contrast, if the corners are curved to become the first curved surface CS1 and the second curved surface CS2 as in the electrostatic chuck member 10, the above-mentioned electrostatic field is dispersed on the first curved surface CS1 and the second curved surface CS2 and is not likely to be concentrated at a specific part. As a result, the attachment parts of the charged foreign particles are dispersed, and the number of charged foreign particles per unit surface area is reduced, and as a result, abnormal discharge is easily suppressed.

[0128] Moreover, if the corners are curved, the areas of the formed first curved surface CS1 and second curved surface CS2 are smaller than the area of the surface formed by extending from the end of the mounting surface 10x along the virtual surface S1 and the virtual surface S2 to the lower end of the second curved surface CS2 (that is, the surface that exists when the corners are not curved). As described above, charged foreign particles are likely to attach to the corners of the electrostatic chuck member. As a result, if the corners are curved, the surface area of the part where the charged foreign particles can attach can be reduced, and thus it is suitable as a structure for suppressing abnormal discharge.

[0129] Furthermore, the electrode 13 has an electrode inclined surface 13A as an electric field dispersion structure.

[0130] Figure 3A and Figure 3BIt is an explanatory diagram for explaining the effect of the inclined surface 13A of the electrode. Figure 3A It is a diagram schematically showing the state when a voltage is applied to the electrode using an electrostatic chuck member that does not have the inclined surface 13A of the electrode. Figure 3B It is a diagram schematically showing the state when a voltage is applied to the electrode using an electrostatic chuck member that has the inclined surface 13A of the electrode. In FIG. 3, it is schematically explained using the electric field lines LE.

[0131] First, as Figure 3A shown, in the electrostatic chuck member 10X that does not have the inclined surface 13A of the electrode, when viewed in cross-section, at the position A where the X-direction end of the upper surface of the electrode 13 contacts the base body (ceramic plate 11), a corner where the electric field tends to concentrate is usually formed. In such an electrostatic chuck member 10X, if a voltage is applied to the electrode 13X during plasma processing, the electric field will concentrate at the corner of position A.

[0132] At this time, if considering the electric field lines LE of the electric field input to the electrode 13, the charged foreign particles flying along the electric field lines LE adhere to the surface of the ceramic plate 11 at intervals such as W1.

[0133] In contrast, as Figure 3B shown, in the electrostatic chuck member 10 that has the inclined surface 13A of the electrode, compared with Figure 3A the electrostatic chuck member 10X, the corner of position A is more obtuse. Therefore, it is considered that in the electrostatic chuck member 10, if a voltage is applied to the electrode 13 during plasma processing, compared with the electrostatic chuck member 10X, the electric field is less likely to concentrate at the corner of position A, and the input electric field is easily dispersed over the entire inclined surface 13A of the electrode.

[0134] At this time, the density of the electric field lines LE of the electric field input to the electrode 13 is sparser than the density of Figure 3A the electrostatic chuck member 10X. Therefore, the charged foreign particles flying along the electric field lines LE adhere to the surface of the ceramic plate 11 at intervals W2 (W2 > W1).

[0135] Therefore, if the electrode 13 has the inclined surface 13A, the electric field that is likely to concentrate on the outer edge 13x during plasma processing is dispersed, and the concentration and fixation of charged foreign particles on the ceramic plate 11 can be suppressed.

[0136] Moreover, the width L2 of the inclined surface 13A (electric field dispersion structure) of the electrode is preferably greater than the thickness T3 of the electrode. Thereby, the angle of the corner of position A can be enlarged, and the concentration of the electric field at position A can be effectively suppressed.

[0137] (Surface roughness)

[0138] The arithmetic mean roughness Ra of the first surface CS1 and the second surface CS2 is preferably 2 μm or less. By setting the arithmetic mean roughness Ra of the first surface CS1 and the second surface CS2 to 2 μm or less, it is possible to reduce the charged foreign particles adhering to the first surface CS1 and the second surface CS2, and effectively suppress the above-mentioned adverse conditions.

[0139] The arithmetic mean roughness Ra can be measured using a surface roughness and profile shape measuring machine (SURFCOM NEX200, manufactured by TOKYO SEIMITSU CO., LTD.). Specifically, for the first surface CS1 and the second surface CS2, when looking down at the electrostatic chuck member 10, the same measurement is performed at four locations every 90° in the circumferential direction. For the measured values of the arithmetic mean roughness Ra obtained at the four locations in the circumferential direction, the average value is calculated and used as the arithmetic mean roughness Ra.

[0140] In the electrostatic chuck members used in conventional electrostatic chuck devices, the Ra of the mounting surface is sometimes mirror-polished to about 0.05 μm, preferably about 0.01 to 0.02 μm. When the electrostatic chuck member has minute projections on the mounting surface, the Ra at the tip of the minute projections sometimes satisfies the above Ra.

[0141] On the other hand, in conventional electrostatic chuck members, the Ra of the side circumferential surface is finished to be rougher than the mounting surface, and is finished with a surface accuracy of about 3 to 4 μm in Ra. The reason is that when manufacturing the electrostatic chuck member, attention is paid to the processing accuracy of the mounting surface in direct contact with the wafer, and the side circumferential surface where the plate-like specimen is not mounted is not concerned. Therefore, in conventional electrostatic chuck members, based on consideration of production efficiency, only the necessary minimum polishing is performed on the side circumferential surface. However, the inventors obtained the following idea: when the surface accuracy of the side circumferential surface is about 3 to 4 μm in Ra, the surface area where charged foreign particles can adhere is very wide, and it is easy to further adsorb charged foreign particles through the internal electrode close to the side circumferential surface, and it is easy for a large amount of charged foreign particles to remain.

[0142] Therefore, a simple and effective method was devised: in the electrostatic chuck member 10, the Ra of the first surface CS1 and the second surface CS2 of the side circumferential surface 10y is set to be smoother than before, at 2 μm or less, to form a structure that reduces the surface area for adsorbing charged foreign particles, and the Ra of the side circumferential surface 10y is halved compared to before, thereby being able to significantly reduce the charged foreign particles adhering to and remaining on the side circumferential surface to less than half compared to before.

[0143] Generally, it is assumed that charged foreign particles repeatedly adsorb to and desorb from the surface of the electrostatic chuck component during the wafer process. Here, it is assumed that if the amount of attachment per unit surface area of the charged foreign particles increases, the charged foreign particles adsorb to the surface of the electrostatic chuck component in the form of an aggregate formed by multiple particles and desorb from the surface. It is considered that in the case where such an aggregate adsorbs to and desorbs from the surface of the electrostatic chuck component, "abnormal discharge" occurs, which first impairs the stability of the plasma and causes a reduction in the yield of the manufactured components.

[0144] That is, in a semiconductor manufacturing apparatus, when charged foreign particles adhere to the side circumferential surface of the electrostatic chuck component during the wafer process, no abnormal discharge occurs at all until the amount of attachment per unit surface area of the charged foreign particles increases to the extent of forming the above-mentioned aggregate, and abnormal discharge occurs only when the threshold value for forming the above-mentioned aggregate is exceeded. In this case, if the amount of attachment of the charged foreign particles is reduced, for example, reduced below the threshold value, the amount of abnormal discharge can be significantly suppressed, and high effects can be expected. The "threshold value" is affected by various conditions such as the structure of the semiconductor manufacturing apparatus, the type of wafer, and the wafer process conditions.

[0145] That is, it is considered that the relationship between the amount of attachment of the charged foreign particles and the number of occurrences of abnormal discharge is not a linear relationship but a corresponding relationship with a threshold value. Therefore, the idea of the inventors, etc. is as follows: By a simple method of reducing the Ra of the side circumferential surface 10y to half of the previous value, it is expected to significantly suppress the occurrence of abnormal discharge.

[0146] The Ra of the first curved surface CS1 and the second curved surface CS2 is preferably 1.5 μm or less, more preferably 1.0 μm or less, further preferably 0.05 μm or less, and particularly preferably 0.01 - 0.02 μm.

[0147] By making the radii of curvature of the first curved surface CS1 and the second curved surface CS2 on the side circumferential surface 10y larger than the thickness of the electrode 13, it is possible to suppress the attachment of charged foreign particles wider than the thickness of the electrode 13 on the side circumferential surface 10y. Therefore, on the side circumferential surface 10y, microdischarge caused by charged foreign particles can be suppressed, and thus dielectric breakdown on the side circumferential surface 10y can be suppressed.

[0148] "Manufacturing Method of Electrostatic Chuck Component"

[0149] Figure 4 It is an explanatory diagram showing an example of the manufacturing method of the above-mentioned electrostatic chuck component. The electrostatic chuck component 10 can be manufactured through the following processes: First, a disk-shaped sintered body having ceramic plates 11, 12, an electrode 13, and an insulating layer 15 and not processed with the first curved surface CS1 and the second curved surface CS2 is obtained (process of obtaining the sintered body), and the side circumferential surface of the obtained sintered body is ground using a rotary grinding stone (grinding process).

[0150] (Process for obtaining a sintered body)

[0151] In the process for obtaining a sintered body, first, an electrode layer forming paste is applied by a coating method such as screen printing on one surface of the ceramic plate 12 that becomes the inner side in the electrostatic chuck member 10 to form an electrode layer coating film. Then, an insulating layer forming paste is applied to form an insulating layer coating film.

[0152] The outer edge of the formed electrode layer coating film and the inner edge of the insulating layer coating film overlap in a plan view, and the contact surface between the electrode layer coating film and the insulating layer coating film has an inclination with respect to the thickness direction of one surface of the ceramic plate 12. The outer edge of the electrode layer coating film has an inclination complementary to the inner edge of the insulating layer coating film.

[0153] As the electrode layer forming paste, a dispersion obtained by dispersing insulating ceramic particles and conductive ceramic particles for forming the electrode 13 in a solvent can be used. As the solvent contained in the electrode layer forming paste, an alcohol such as isopropyl alcohol is used.

[0154] As the insulating layer forming paste, a dispersion obtained by dispersing insulating ceramics for forming the insulating layer 15 in a solvent can be used. As the solvent contained in the insulating layer forming paste, an alcohol such as isopropyl alcohol is used.

[0155] Next, the ceramic plate 11 is laminated from one surface side of the ceramic plate 12 in such a manner that the surface on which the electrode layer coating film and the insulating layer coating film are formed becomes the inner side.

[0156] Next, while heating the laminate including the ceramic plate 12, the electrode layer coating film, the insulating layer coating film, and the ceramic plate 11, pressure is applied in the thickness direction. The atmosphere during heating the laminate while applying pressure in the thickness direction is preferably a vacuum or an inert atmosphere such as Ar, He, N2.

[0157] The temperature for heating the laminate (heat treatment temperature) is preferably 1600 °C or higher and 1900 °C or lower, more preferably 1650 °C or higher and 1850 °C or lower. If the temperature for heating the laminate is 1600 °C or higher and 1900 °C or lower, the solvent contained in each coating film can be volatilized, so that the electrode 13 and the insulating layer 15 can be formed between the ceramic plate 12 and the ceramic plate 11. And the ceramic plate 12 and the ceramic plate 11 can be joined and integrated via the electrode 13 and the insulating layer 15.

[0158] The pressure (applied force) applied to the laminate in the thickness direction is preferably 1.0 MPa to 50.0 MPa, more preferably 5.0 MPa to 20.0 MPa. When the pressure applied to the laminate in the thickness direction is 1.0 MPa to 50.0 MPa, electrodes 13 and insulating layers 15 can be formed in close contact between ceramic plates 12 and 11. Furthermore, ceramic plates 12 and 11 can be joined and integrated via electrodes 13 and insulating layers 15.

[0159] In this manner, a disk-shaped sintered body including the ceramic plates 11 and 12 , the electrode 13 , and the insulating layer 15 can be obtained.

[0160] (Grinding process)

[0161] In the grinding step, the side peripheral surface of the obtained sintered body is ground.

[0162] At this time, the cross section of the rotating grindstone G including the rotating axis L of the rotating grindstone G has the same Figure 2 3 , the shape of the first curved surface CS1, the shape of the second curved surface CS2, and the shape of the inclined surface 10a are complementary. On the rotating grindstone G, the radius of curvature of the portion corresponding to the first curved surface CS1 is the same as that of the first curved surface CS1, i.e., r1. Furthermore, the radius of curvature of the portion corresponding to the second curved surface CS2 is also the same as that of the second curved surface CS2, i.e., r2. By grinding the peripheral portion of the mounting surface 10x using this rotating grindstone, an electrostatic chuck component 10 having the first curved surface CS1 and the second curved surface CS2 can be easily formed.

[0163] This manufacturing method eliminates the need to change the fixed angle of the grindstone to form the first curved surface CS1 and the second curved surface CS2, thereby making it possible to easily manufacture an electrostatic chuck component having the first curved surface CS1 and the second curved surface CS2. Furthermore, by manufacturing the rotating grindstone G with high precision, the electrostatic chuck component 10 can be manufactured with high reproducibility.

[0164] In the above description, the rotating grindstone G has a shape that complements the first curved surface CS1 and the second curved surface CS2. However, a rotating grindstone having a shape that complements at least a portion of either the first curved surface CS1 or the second curved surface CS2 may also be used for machining. Furthermore, using such a rotating grindstone for machining can significantly reduce the need for grinding stone replacement or angle adjustment, thereby improving production efficiency. Furthermore, manufacturing variations caused by grinding stone replacement or angle adjustment can be suppressed.

[0165] According to the electrostatic chuck component 10 having the above-described structure, it is possible to reduce problems (productivity reduction, insulation breakdown) caused by charged foreign particles adhering to the side peripheral surface 10 y .

[0166] In addition, in the present embodiment, the side circumferential surface 10y has two convex curved surfaces (the first curved surface CS1 and the second curved surface CS2), but it is not limited thereto. The side circumferential surface 10y may also have the following structure: in addition to having the convex curved surface (i.e., the first curved surface CS1) provided along the circumferential direction at the peripheral portion of the mounting surface 10x and the second curved surface CS2 provided along the circumferential direction at a height position different from that of the first curved surface CS1, it also has convex curved surfaces (i.e., the third curved surface, the fourth curved surface, etc.) provided along the circumferential direction at height positions different from that of the first curved surface CS1.

[0167] [Second Embodiment]

[0168] Figure 5 FIG. is an explanatory diagram of the electrostatic chuck member 20 according to the second embodiment. In the following embodiments, the same materials as those of the electrostatic chuck member 10 of the first embodiment can be used, and the shapes of the electrostatic chuck members are different. In the following embodiments, detailed descriptions of the same constituent elements as those of the first embodiment are omitted.

[0169] As Figure 5 shown, the electrostatic chuck member 20 includes a pair of ceramic plates 11 and 22, and an electrostatic adsorption electrode 23 and an insulating layer 25 interposed between the pair of ceramic plates 11 and 22. The structure formed by combining the pair of ceramic plates 11 and 22 and the insulating layer 25 corresponds to the base body of the present invention. The electrode 23 has an electrode inclined surface 23A at its outer edge portion. The electrode inclined surface 23A has the same structure as the above-mentioned electrode inclined surface 13A.

[0170] The ceramic plate 11 is the same as the ceramic plate of the above-mentioned electrostatic chuck member 10. At the upper end portion of the side circumferential surface 20y of the electrostatic chuck member 20, similar to the above-mentioned electrostatic chuck member 10, a first curved surface CS1, an inclined surface 20a, and a second curved surface CS2 are formed.

[0171] Moreover, the side circumferential surface 20y has a portion 20z extending outward at the lower end portion of the side circumferential surface 20y. The upper surface of this portion 20z is a concave curved surface CS0 provided along the circumferential direction of the electrostatic chuck member 20. That is, the side circumferential surface 20y is formed by the first curved surface CS1, the inclined surface 20a, the second curved surface CS2 on the upper end side, the concave curved surface CS0 on the lower end side, and a main surface 20b connecting the second curved surface CS2 and the concave curved surface CS0. The main surface 20b is a surface extending in the Y direction.

[0172] The electrostatic chuck member 20 may form the first curved surface CS1 and the second curved surface CS2 on a part in the circumferential direction of the side circumferential surface 20y, or may form the first curved surface CS1 and the second curved surface CS2 on the entire circumference. Moreover, the curvatures of the first curved surface CS1 and the second curved surface CS2 may be constant in the circumferential direction or different in the circumferential direction.

[0173] Further, the electrostatic chuck member 30 may form a concave curved surface CS0 in a part of the circumferential direction of the side circumferential surface 30y, or may form a concave curved surface CS0 in the entire circumferential direction. Further, the radius of curvature of the concave curved surface CS0 may be constant in the circumferential direction or may be different in the circumferential direction.

[0174] Generally, it is known that in the lower part of the side circumferential surface of an electrostatic chuck member, plasma is not easily reached during plasma cleaning, and even if charged foreign particles are attached, they are not easily removed. In contrast, in the electrostatic chuck member 20, a concave curved surface CS0 is formed on the lower end side of the side circumferential surface 20y and is exposed in the field of view in a plan view. As a result, plasma cleaning of the lower end side of the side circumferential surface 20y becomes easy. Further, the charged foreign particles detached from the side circumferential surface 20y by plasma cleaning fly out in the Y direction, so they are not easily floating near the side circumferential surface 20y, and thus reattachment is easily suppressed.

[0175] The radius of curvature r0 of the concave curved surface CS0 is preferably equal to or greater than the thickness T3 of the electrode 23.

[0176] The radius of curvature r1 of the first curved surface CS1 and the radius of curvature r0 of the concave curved surface CS0 preferably have the relationship of the following formula (1).

[0177] [Radius of curvature r1 of the first curved surface CS1] < [Radius of curvature r0 of the concave curved surface CS0]... (1)

[0178] Further, the radius of curvature r2 of the second curved surface CS2 and the radius of curvature r0 of the concave curved surface CS0 preferably have the relationship of the following formula (2).

[0179] [Radius of curvature r2 of the second curved surface CS2] < [Radius of curvature r0 of the concave curved surface CS0]... (2)

[0180] In the side circumferential surface of a general electrostatic chuck member, abnormal discharge is likely to occur at the upper corner where the attracting electric field is concentrated and charged foreign particles are concentrated in a narrow range, and at the lower corner where the shielding property is high and charged foreign particles are likely to accumulate in a large amount. In the electrostatic chuck member 20, by setting the upper corner as the first curved surface CS1 and the second curved surface CS2 and setting the lower corner as the concave curved surface CS0, the accumulation of charged foreign particles is suppressed.

[0181] Here, if the first curved surface CS1 and the second curved surface CS2 are formed to be large, the placement surface 20x becomes relatively narrow, and the area of the plate-like specimen that can be placed becomes small.

[0182] On the other hand, for an electrostatic chuck member that satisfies the above (1) and (2), it is easy to balance ensuring the area of the placement surface 20x and suppressing abnormal discharge, and thus it is preferred.

[0183] Preferably, the arithmetic mean roughness Ra of the concave curved surface CS0 is 2 μm or less. By setting the arithmetic mean roughness Ra of the concave curved surface CS0 to 2 μm or less, two effects, namely the effect based on the concave curved surface CS0 and the effect based on the improved surface accuracy, can be obtained, and the attachment of charged foreign particles can be effectively suppressed. Similarly to the above-described curved surface, the Ra of the concave curved surface CS0 is preferably 1.5 μm or less, more preferably 1.0 μm or less, further preferably 0.05 μm or less, and particularly preferably 0.01 to 0.02 μm.

[0184] In the direction orthogonal to the normal direction of the mounting surface 20x, the distance from the main surface 20b to the outer end of the concave curved surface CS0 (the width L3 of the portion 20z in the X direction) is preferably equal to or greater than the thickness T3 of the electrode 23.

[0185] According to the electrostatic chuck member 20 having the above-described structure, the concentration of the electrostatic field can also be suppressed by the above-described electrode inclined surface (electric field dispersion structure) and the functions of the convex curved surface and the concave curved surface provided on the side peripheral surface, thereby suppressing the attachment of charged foreign particles, and the problems (decrease in productivity, insulation breakdown) caused by the attachment of charged foreign particles to the side peripheral surface 20y can be reduced.

[0186] In addition, in the present embodiment, the main surface 20b is set to a surface parallel to the Y direction, but it is not limited thereto. The main surface 20b may also be set to an inclined surface exposed in the top view.

[0187] [Third Embodiment]

[0188] Figure 6 It is an explanatory view of the electrostatic chuck member 30 according to the third embodiment. As Figure 6 shown, the electrostatic chuck member 30 includes a pair of ceramic plates 31 and 32, and an electrostatic adsorption electrode 33 and an insulating layer 35 interposed between the pair of ceramic plates 31 and 32. The structure formed by combining the pair of ceramic plates 31 and 32 and the insulating layer 35 corresponds to the base body of the present invention. The electrode 33 has an electrode inclined surface 33A at the outer edge portion. The electrode inclined surface 33A has the same structure as the above-described electrode inclined surface 13A.

[0189] The upper end portion of the side peripheral surface 30y of the electrostatic chuck member 30 is chamfered and formed with a first curved surface CS1 exposed in the view from the normal direction of the mounting surface 30x. The first curved surface CS1 is a convex curved surface.

[0190] The electrostatic chuck member 30 may form the first curved surface CS1 in a part in the circumferential direction of the side peripheral surface 30y, or may form the first curved surface CS1 in the entire circumferential direction. And, the radius of curvature of the first curved surface CS1 may be constant in the circumferential direction or may be different in the circumferential direction.

[0191] Further, at the lower end of the side peripheral surface 30y, the side peripheral surface 30y has a portion 30z extending outward, similar to the electrostatic chuck member 20 of the second embodiment. The upper surface of the portion 30z is a concave curved surface CS0 provided along the circumferential direction of the electrostatic chuck member 30. The concave curved surface CS0 corresponds to the "second curved surface" in the present invention.

[0192] The radius of curvature r1 of the first curved surface CS1, the radius of curvature r0 of the concave curved surface CS0, the thickness T3 of the electrode 33, and the thickness (the thickness of the substrate from the lower surface of the electrostatic adsorption electrode to the lower surface of the substrate) T2 of the ceramic plate 32 preferably have the relationship of the following formula (3).

[0193] [Thickness T3 of electrode 33]<[Radius of curvature r1 of first curved surface CS1]<[Radius of curvature r0 of concave curved surface CS0]<[Thickness T2 of ceramic plate 32]…(3)

[0194] First, as described above, if [Radius of curvature r1 of first curved surface CS1]<[Radius of curvature r0 of concave curved surface CS0] is satisfied, it is easy to balance ensuring the area of the placement surface 30x and suppressing abnormal discharge, so it is preferred.

[0195] Next, in the electrostatic chuck member where [Thickness T3 of electrode 33]<[Radius of curvature r1 of first curved surface CS1], the electric field concentrated at the corner of the upper part of the side peripheral surface in the conventional electrostatic chuck member (the electrostatic chuck member without the first curved surface CS1) can be dispersed more widely than the thickness of the electrode 33, so that the accumulation of charged foreign particles can be suppressed.

[0196] Moreover, in the electrostatic chuck member where [Radius of curvature r0 of concave curved surface CS0]<[Thickness T2 of ceramic plate 32], the plan view area of the electrostatic chuck member does not become too large, and defects or cracks are not likely to occur on the ceramic plate 32, so it is preferred.

[0197] The arithmetic mean roughness Ra of the first curved surface CS1 and the concave curved surface CS0 is preferably 2 μm or less. The Ra of the first curved surface CS1 and the concave curved surface CS0 is preferably 1.5 μm or less, more preferably 1.0 μm or less, further preferably 0.05 μm or less, and particularly preferably 0.01 - 0.02 μm.

[0198] According to the electrostatic chuck member 30 having the above-described structure, the problems (productivity decrease, dielectric breakdown) caused by the attachment of charged foreign particles to the side peripheral surface 30y can also be reduced by the above-described electrode inclined surface (electric field dispersion structure) and the functions of the convex and concave curved surfaces provided on the side peripheral surface.

[0199] In addition, in the present embodiment, the main surface 30b is set to be parallel to the Y direction, but it is not limited thereto. The main surface may also be an inclined surface exposed in the top view.

[0200] Figure 7 It is an explanatory view of the electrostatic chuck member 40 according to a modified example of the third embodiment. As Figure 7 shown, the electrostatic chuck member 40 includes a pair of ceramic plates 41, 42, and an electrostatic adsorption electrode 43 and an insulating layer 45 interposed between the pair of ceramic plates 41, 42. The structure formed by combining the pair of ceramic plates 41, 42 and the insulating layer 45 corresponds to the substrate of the present invention. The electrode 33 has an electrode inclined surface 33A at the outer edge portion. The electrode inclined surface 33A has the same structure as the above-mentioned electrode inclined surface 13A.

[0201] The side peripheral surface 40y has a first curved surface CS1 provided at the upper end and a concave curved surface CS0 provided at the lower end. The concave curved surface CS0 is provided in a portion 40z extending outward. The surface (main surface) 40b between the first curved surface CS1 and the concave curved surface CS0 is a continuous linear inclined surface.

[0202] The electrostatic chuck member 40 may have a part of the circumference of the main surface 40b as an inclined surface, or the entire circumference of the main surface 40b may be an inclined surface. Moreover, the inclination angle θ of the main surface 40b may be constant in the circumferential direction or different in the circumferential direction.

[0203] According to the electrostatic chuck member 40 having the above-described structure, it is also possible to suppress the concentration of the electrostatic field by the above-described electrode inclined surface (electric field dispersion structure) and the functions of the convex curved surface and the concave curved surface provided on the side peripheral surface, and suppress the adhesion of charged foreign particles, and it is possible to reduce the problems (decrease in productivity, insulation breakdown) caused by the adhesion of charged foreign particles to the side peripheral surface 40y.

[0204] [Fourth Embodiment]

[0205] Figure 8 It is an explanatory view of the electrostatic chuck member 50 according to the fourth embodiment. The electrostatic chuck member 50 includes a pair of ceramic plates 11, 12 having the same structure as the electrostatic chuck member 10 of the first embodiment, and an electrostatic adsorption electrode 53 and an insulating layer 55 interposed between the pair of ceramic plates 11, 12.

[0206] The electrode 53 has an electrode inclined surface 53A at the outer edge portion. The electrode inclined surface 53A is a convex curved surface protruding toward the mounting surface 10x side. The electrode inclined surface 53A corresponds to the "electric field dispersion structure" in the present invention.

[0207] The surface of the insulating layer 55 in contact with the electrode 53 has a shape complementary to the electrode inclined surface 53A.

[0208] In this electrostatic chuck member 50, unlike the electrostatic chuck member 10X shown in Figure 3A there are no corners where the electric field tends to concentrate when a voltage is applied to the electrode 53 during plasma processing. Therefore, in the electrostatic chuck member 50, the electric field is less likely to concentrate on the outer edge of the electrode 53, and the input electric field is dispersed over the entire electrode inclined surface 53A. As a result, the concentration and fixation of charged foreign particles on the ceramic plate 11 can be suppressed.

[0209] According to the electrostatic chuck member 50 having the above-described structure, it is also possible to suppress the concentration of the electrostatic field and the attachment of charged foreign particles by the above-described electrode inclined surface (electric field dispersion structure) and the functions of the convex and concave surfaces provided on the side peripheral surface, and it is possible to reduce the problems (decrease in productivity, insulation breakdown) caused by the attachment of charged foreign particles to the side peripheral surface 10y.

[0210] [Fifth Embodiment]

[0211] Figure 9 FIG. is an explanatory view of an electrostatic chuck member 60 according to the fifth embodiment. The electrostatic chuck member 60 includes a pair of ceramic plates 11 and 12 having the same structure as the electrostatic chuck member 10 of the first embodiment, an electrostatic adsorption electrode 63, and an insulating layer 65 interposed between the pair of ceramic plates 11 and 12.

[0212] A low-density portion 63A is provided at the outer edge portion of the electrode 63. The relative density of the low-density portion 63A is lower than the relative density at the center of the electrode 63 when viewed from above. The low-density portion 63A corresponds to the "electric field dispersion structure" in the present invention. In the low-density portion 63A, fine air holes are provided inside the electrode 63, and the density is lower than that of the solid portion.

[0213] The density (relative density) of the low-density portion 63A is obtained from a micrograph of a cross section of the electrostatic chuck member 60.

[0214] (Method for Measuring the Relative Density of the Low-Density Portion)

[0215] For the same cross section as Figure 9 a micrograph with a magnification of 1000 times is taken using a microscope (for example, a digital microscope (VFX-900F) manufactured by KEYENCE CORPORATION). When measuring the relative density of the outer edge of the electrode 63, the photographing range is the outer edge of the electrode 63 and the region including the insulating layer 65.

[0216] The low-density portion 63A has a lower light reflectivity (reflection intensity) compared to other portions. Therefore, when observing the cross-section of the electrostatic chuck member with an optical microscope, the presence of the low-density portion 63A can be identified and distinguished by the color difference from the surroundings. At this time, when observing the cross-section of the electrostatic chuck member with a polarized light microscope, the low-density portion 63A can be more clearly distinguished.

[0217] Moreover, when observing the cross-section of the electrostatic chuck member with a digital microscope, the intensity of the reflected light in a specified area can be easily numericalized and charted. Based on the values or charts obtained in this way, the area with a low reflectivity can be identified as the low-density portion 63A.

[0218] Specifically, when calculating the reflection intensity from the region A (a region inside the low-density portion 63A where the reflection intensity is approximately constant) towards the low-density portion 63A with the reflection intensity of region A as a reference, the position where the reflection intensity is 1 / e times the reflection intensity of region A is set as the boundary position between region A and the low-density portion 63A.

[0219] Similarly, when calculating the reflection intensity from the region B (a region outside the low-density portion 63A where the reflection intensity is approximately constant) towards the low-density portion 63A with the reflection intensity of region B as a reference, the position where the reflection intensity is 1 / e times the reflection intensity of region B is set as the boundary position between region B and the low-density portion 63A.

[0220] The range between the two boundary positions obtained in this way can be defined as the two ends of the low-density portion 63A in the X direction.

[0221] From the above microscope photograph, on the virtual plane overlapping with the cross-section of the electrode 63, it is possible to distinguish the region where the conductive ceramic and the insulating ceramic constituting the electrode 63 exist (the region where the substance exists. Region 1) and the region of "pores" where neither the conductive ceramic nor the insulating ceramic exists (Region 2).

[0222] The relative density of the outer edge of the electrode 63 is the value representing the ratio of the area of region 1 to the area within the outer contour of the density measurement region (i.e., the total area of region 1 and region 2) in percentage. When there are no pores in the electrode 63, the relative density of the density measurement region is 100%.

[0223] Moreover, when measuring the relative density at the center of the electrode 63, the shooting range is the region including the center in the X direction of the electrode 63. Additionally, when it can be reasonably judged from the microscope photograph that the density is the same as that at the center of the electrode 63, the shooting range may not strictly include the center of the electrode 63.

[0224] In the obtained micrographs, for the electrode 63 included within a range of 150 μm in width in the X direction, calculation is performed in the same manner as in the case of the density of the outer edge of the measurement electrode 63, whereby the relative density at the center of the electrode 63 is obtained.

[0225] By comparing the relative densities obtained in the above-described manner, it is possible to determine whether the density of the outer edge of the electrode 63 is lower than the density at the center of the electrode 63.

[0226] In the electrostatic chuck member 60, the width of the low-density portion 63A (the distance in the direction from the center of the electrode 63 toward the outer edge) is preferably greater than the thickness T3 of the electrode 63.

[0227] The electric field tends to concentrate in a portion with a relatively high density and does not easily concentrate in a low-density portion. Therefore, in the electrostatic chuck member 60, the electric field does not easily concentrate in the low-density portion 63A of the electrode 63 but is dispersed. As a result, it is possible to suppress the concentrated adhesion of charged foreign particles on the ceramic plate 11.

[0228] If the low-density portion 63A is too small, it is difficult to effectively disperse the concentration of the electric field at the outer edge of the electrode 63. On the other hand, if the low-density portion 63A is too large, the adsorption force at the end of the plate-shaped specimen placed on the placement surface may decrease. Therefore, the low-density portion 63A is preferably arranged in a range from the outer edge of the electrode 63 toward the inner direction of the electrode 63 that is not less than the thickness T3 of the electrode 63 and within 10 times the thickness T3, and more preferably arranged in a range not less than the thickness T3 and within 5 times the thickness T3.

[0229] According to the electrostatic chuck member 60 having the above-described structure, it is also possible to suppress the concentration of the electrostatic field and suppress the adhesion of charged foreign particles by the above-described low-density portion (electric field dispersion structure) and the functions of the convex and concave surfaces provided on the side peripheral surface, and it is possible to reduce the problems (decrease in productivity, insulation breakdown) caused by the adhesion of charged foreign particles to the side peripheral surface 10y.

[0230] [Sixth Embodiment]

[0231] Figure 10 It is an explanatory view of an electrostatic chuck member 70 according to the sixth embodiment. The electrostatic chuck member 70 includes a pair of ceramic plates 11 and 12 having the same structure as the electrostatic chuck member 10 of the first embodiment, and an electrostatic adsorption electrode 73 and an insulating layer 75 interposed between the pair of ceramic plates 11 and 12.

[0232] The electrostatic chuck member 70 has a gap 73A between the outer edge of the electrode 73 and the insulating layer 75 (substrate). In the electrostatic chuck member 70, the width of the gap 73A (the distance in the direction from the center of the electrode 73 toward the outer edge) is preferably greater than the thickness T3 of the electrode 73.

[0233] The electric field tends to concentrate in the part with a relatively high dielectric constant and is not easily concentrated in the part with a low dielectric constant. Therefore, in the electrostatic chuck member 70, the electric field is not easily concentrated in the gap 73A of the electrode 73 but is dispersed. As a result, the concentration and fixation of charged foreign particles on the ceramic plate 11 can be suppressed.

[0234] If the gap 73A is too small, it is difficult to effectively disperse the electric field concentration at the outer edge of the electrode 73. On the other hand, if the gap 73A is too large, the adsorption force at the end of the plate-shaped specimen placed on the placement surface may decrease. Therefore, the gap 73A is preferably arranged in the range of not less than the thickness T3 of the electrode 73 and not more than 10 times the thickness T3 in the direction from the outer edge of the electrode 73 toward the inside of the electrode 73, and more preferably arranged in the range of not less than the thickness T3 and not more than 5 times the thickness T3.

[0235] According to the electrostatic chuck member 70 having the above-described structure, it is also possible to suppress the concentration of the electrostatic field and the attachment of charged foreign particles by the above-described low-density portion (electric field dispersion structure) and the functions of the convex and concave curved surfaces provided on the side peripheral surface, and it is possible to reduce the problems (decrease in productivity, insulation breakdown) caused by the attachment of charged foreign particles to the side peripheral surface 10y.

[0236] [Electrostatic chuck device]

[0237] Hereinafter, with reference to Figure 11 An example of an electrostatic chuck device according to an embodiment of the present invention will be described. In the following description, an electrostatic chuck device having the above-described electrostatic chuck member 10 will be described, but the electrostatic chuck device can also employ the above-described other electrostatic chuck members respectively. In the following description, the same reference numerals are given to the constituent elements identical to those in the first embodiment, and the detailed description thereof is omitted.

[0238] Figure 11 It is a cross-sectional view showing the electrostatic chuck device of the present embodiment. The electrostatic chuck device 100 includes a disk-shaped electrostatic chuck member 10, a disk-shaped base member 103 that cools the electrostatic chuck member 10 and adjusts it to a desired temperature, and an adhesive layer 104 that joins and integrates these electrostatic chuck member 10 and base member 103.

[0239] In the following description, the side of the electrostatic chuck member 10 may be referred to as "upper", and the side of the base member 103 may be referred to as "lower" to indicate the relative positions of the respective structures.

[0240] [Electrostatic chuck member]

[0241] The electrostatic chuck component 10 includes, in addition to the ceramic plates 11 and 12 , the electrode 13 , and the insulating layer 15 , a power supply terminal 116 provided in a fixing hole 115 of the base member 103 so as to contact the electrode 13 .

[0242] [Power supply terminal]

[0243] The power supply terminal 116 is a component for applying a voltage to the electrode 13 .

[0244] The number, shape, etc. of the power supply terminals 116 are determined according to the form of the electrode 13 , that is, whether it is a monopolar type or a bipolar type.

[0245] The material of power supply terminal 116 is not particularly limited as long as it is a conductive material with excellent heat resistance. The material of power supply terminal 116 is preferably a material having a thermal expansion coefficient similar to that of electrode 13 and ceramic plate 12. For example, metal materials such as Kovar and niobium (Nb) or various conductive ceramics can be suitably used.

[0246] [Conductive adhesive layer]

[0247] The conductive adhesive layer 117 is provided in the fixing hole 115 of the base member 103 and in the through hole 118 of the ceramic plate 12. The conductive adhesive layer 117 is interposed between the electrode 13 and the power supply terminal 116 to electrically connect the electrode 13 and the power supply terminal 116.

[0248] The conductive adhesive constituting the conductive adhesive layer 117 includes a conductive substance such as carbon fiber or metal powder, and resin.

[0249] The resin contained in the conductive adhesive is not particularly limited as long as it is a resin that is less likely to undergo cohesive failure due to thermal stress, and examples thereof include silicone resins, acrylic resins, epoxy resins, phenolic resins, polyurethane resins, and unsaturated polyester resins.

[0250] Among these, silicone resins are preferred from the viewpoint of high elasticity and low likelihood of cohesive failure due to thermal stress changes.

[0251] [Base parts]

[0252] Base member 103 is a thick, disc-shaped member formed from at least one of metal and ceramic. The main body of base member 103 also serves as an internal electrode for plasma generation. A flow path 121 is formed within the main body of base member 103, through which a cooling medium such as water, He gas, or N₂ gas circulates.

[0253] The main body of the base member 103 is connected to an external high-frequency power supply 122. Further, within the fixing hole 115 of the base member 103, a power supply terminal 116 whose outer periphery is surrounded by an insulating material 123 is fixed via the insulating material 123. The power supply terminal 116 is connected to an external DC power supply 124.

[0254] The material constituting the base member 103 is not particularly limited as long as it is a metal having excellent thermal conductivity, electrical conductivity, and workability or a composite material containing these metals. As the material constituting the base member 103, for example, aluminum (Al), copper (Cu), stainless steel (SUS), titanium (Ti), etc. can be suitably used.

[0255] It is preferable to perform anodic oxidation or resin coating using a polyimide-based resin on at least the surface of the base member 103 that is exposed to the plasma. Further, it is more preferable to perform the anodic oxidation or resin coating on the entire surface of the base member 103.

[0256] By performing anodic oxidation or resin coating on the base member 103, the plasma resistance of the base member 103 is improved, and abnormal discharge can be prevented. Therefore, the plasma stability of the base member 103 is improved, and the occurrence of surface damage to the base member 103 can be prevented.

[0257] [Adhesive layer]

[0258] The adhesive layer 104 is a structure that integrally bonds the electrostatic chuck member 10 and the base member 103.

[0259] The thickness of the adhesive layer 104 is preferably 100 μm or more and 200 μm or less, and more preferably 130 μm or more and 170 μm or less.

[0260] If the thickness of the adhesive layer 104 is within the above range, the adhesive strength between the electrostatic chuck member 10 and the base member 103 can be sufficiently maintained. Further, the thermal conductivity between the electrostatic chuck member 10 and the base member 103 can be sufficiently ensured.

[0261] The adhesive layer 104 is formed of, for example, a cured product obtained by heating and curing a silicone-based resin composition, an acrylic resin, an epoxy resin, or the like.

[0262] The silicone-based resin composition is a silicon compound having a siloxane bond (Si-O-Si) and is a resin having excellent heat resistance and elasticity, and thus is more preferable.

[0263] As such a silicone-based resin composition, a silicone resin having a thermal curing temperature of 70°C to 140°C is particularly preferable.

[0264] Here, if the thermal curing temperature is lower than 70°C, when the electrostatic chuck member 10 and the base member 103 are joined in a facing state, since curing does not proceed sufficiently during the joining process and the operability is poor, it is not preferred. On the other hand, if the thermal curing temperature exceeds 140°C, the thermal expansion difference between the electrostatic chuck member 10 and the base member 103 is large, the stress between the electrostatic chuck member 10 and the base member 103 increases, and thus peeling sometimes occurs between them, so it is not preferred.

[0265] That is, if the thermal curing temperature is 70°C or higher, the operability is excellent during the joining process, and if the thermal curing temperature is 140°C or lower, it is difficult to peel between the electrostatic chuck member 10 and the base member 103, so it is preferred.

[0266] According to the electrostatic chuck device 100 of the present embodiment, since it has the above-described electrostatic chuck member 10, it is possible to suppress dielectric breakdown (discharge) from occurring on the side peripheral surface of the electrostatic chuck member.

[0267] In addition, the electrostatic chuck device 100 may have a focus ring surrounding the electrostatic chuck member. In this case, the shape of the focus ring may also be changed to a complementary shape according to the shape of the side peripheral surface of the electrostatic chuck member.

[0268] [Semiconductor manufacturing apparatus]

[0269] Figure 12 It is an explanatory diagram showing an example of a semiconductor manufacturing apparatus having the above-described electrostatic chuck device. The semiconductor manufacturing apparatus 1000 includes an electrostatic chuck device 100, a vacuum chamber 200, an upper electrode 300, a magnet 400, a gas supply mechanism 500, a vacuum pump 600, and a plasma stabilization system 700.

[0270] The vacuum chamber 200 is used as a reaction field for accommodating the electrostatic chuck device 100 and performing plasma processing inside. The vacuum chamber 200 can adopt a known structure used in semiconductor manufacturing apparatuses. The vacuum chamber 200 has a gate (not shown) for loading and unloading plate-shaped specimens.

[0271] The upper electrode 300 is a counter electrode that is accommodated inside the vacuum chamber 200 and is used in cooperation with the electrostatic chuck device 100 when generating plasma inside the vacuum chamber 200. The upper electrode 300 is connected to a power supply (not shown).

[0272] The magnet 400 is disposed around the vacuum chamber 200 and generates a longitudinal magnetic field in the space between the upper electrode 300 and the electrostatic chuck device 100 inside the vacuum chamber 200.

[0273] The gas supply mechanism 500 supplies plasma gas Gas into the vacuum chamber 200. The gas supply mechanism 500 supplies plasma gas Gas into the vacuum chamber 200, for example, through a gas hole provided in the upper electrode 300.

[0274] The vacuum pump 600 discharges the gas in the vacuum chamber 200 and adjusts the atmosphere for generating plasma. The vacuum pump 600 is connected, for example, to a position in the vacuum chamber 200 that is lower than the electrostatic chuck device 100.

[0275] The plasma stabilization system 700 detects and compensates for various external factors that cause changes in the state of the plasma generated in the semiconductor manufacturing apparatus 1000, thereby stabilizing the state of the plasma. The plasma stabilization system 700 includes a detector 710 and a control unit 720 that controls the semiconductor manufacturing apparatus 1000 based on the detection results detected by the detector 710.

[0276] The detector 710 directly or indirectly detects the state of the plasma in the vacuum chamber 200. The detector 710 can be one or more. Examples of the items detected by the detector 710 include, for example, the degree of vacuum in the vacuum chamber 200, the color of the plasma, the temperature of the plasma, the capacitance between the upper electrode 300 and the internal electrode (not shown) for plasma generation provided in the electrostatic chuck device 100, and the inductance between the upper electrode 300 and the internal electrode for plasma generation.

[0277] The control unit 720 controls the semiconductor manufacturing apparatus 1000 based on the detection values of the respective items detected by the detector 710 or the change amount per unit time of the detection values. The control unit 720 pre-stores the correspondence relationship between the detection values of the above items and the state of the plasma generated in the vacuum chamber 200. The control unit 720 performs feedback control on the semiconductor manufacturing apparatus 1000 based on the detection values and the above correspondence relationship so that the state of the plasma falls within a preset range. Examples of the items for feedback control include the temperature, degree of vacuum, and bias voltage inside the semiconductor manufacturing apparatus.

[0278] Thereby, the plasma stabilization system 700 can suppress long-term changes in the plasma state in the semiconductor manufacturing apparatus 1000, thereby stabilizing the state.

[0279] Such a plasma stabilization system is effective in suppressing long-term changes in the plasma state of the entire manufacturing process using the semiconductor manufacturing apparatus. On the other hand, the plasma stabilization system has no effect of suppressing state changes for factors that occur in an extremely short time, such as abnormal discharges in the wafer process.

[0280] On the other hand, since the semiconductor manufacturing apparatus 1000 has the above-described electrostatic chuck device 100, abnormal discharge occurring in the wafer process can be suppressed. Therefore, the semiconductor manufacturing apparatus 1000 can stabilize the plasma both in the long term and in the short term by having the plasma stabilization system 700.

[0281] In addition, the control unit 720 may be an inherent structure of the plasma stabilization system 700, and a control device that controls the semiconductor manufacturing apparatus 1000 may also have this function.

[0282] In such a semiconductor manufacturing apparatus 1000, for example, depending on the position of the exhaust port of the vacuum chamber 200 (the connection position of the vacuum pump 600), the tendency of the attachment of charged foreign particles on the side peripheral surface of the electrostatic chuck member 10 may sometimes be different. In the case where the above tendency has been empirically determined for the semiconductor manufacturing apparatus 1000, the electrostatic chuck member 10 may adopt the following structure: by making the arithmetic mean roughness Ra of the side peripheral surface at the position where charged foreign particles are likely to attach smaller than that of other side peripheral surfaces, etc., the attachment of charged foreign particles is suppressed.

[0283] According to the semiconductor manufacturing apparatus 1000 of the present embodiment, since it has the above-described electrostatic chuck device 100, dielectric breakdown (discharge) can be suppressed.

[0284] Moreover, the semiconductor manufacturing apparatus 1000 can suppress abnormal discharge (short-term variation of plasma) through the electrostatic chuck device 100, and can suppress long-term variation of plasma through the plasma stabilization system 700. Therefore, not only can stable plasma processing be performed, but also a semiconductor manufacturing apparatus with improved yield can be provided.

[0285] As described above, the preferred embodiment of the present invention has been described with reference to the accompanying drawings, but the present invention is not limited to this example. The shapes or combinations of the respective components shown in the above example are for example, and various changes can be made based on design requirements and the like without departing from the gist of the present invention. For example, materials, positions, ratios, amounts, types, numbers, sizes, values, etc. can be omitted, added, changed, replaced, exchanged, and other changes can be made. Between embodiments, the preferred conditions or examples can be exchanged or shared with each other.

[0286] Moreover, in the above description, a silicon wafer has been described, but obviously, the wafers that can be processed by the electrostatic chuck member of the present invention can be not only silicon, but also indium phosphide-based, gallium arsenide-based, or other materials.

[0287] Industrial Applicability

[0288] The present invention provides an electrostatic chuck component that can solve the problems caused by the attachment of charged foreign particles to the side surface, and in particular, can reduce abnormal discharges occurring in the wafer process. Further, an electrostatic chuck device having such an electrostatic chuck component is provided.

[0289] Explanation of Reference Numerals

[0290] 10, 10X, 20, 30, 40, 50, 60, 70 - Electrostatic chuck components

[0291] 10a, 20a - Inclined surfaces

[0292] 10x, 20x, 30x - Mounting surfaces

[0293] [[ID=I5]]10y, 20y, 30y, 40y - Side circumferential surfaces

[0294] 11, 12, 22, 31, 32, 41, 42 - Ceramic plates

[0295] 13, 13X, 23, 33, 43, 53, 63, 73 - Electrodes (electrostatic adsorption electrodes)

[0296] 13A, 23A, 33A, 53A - Electrode inclined surfaces

[0297] 13x - Outer edge

[0298] 15, 25, 35, 45, 55, 65, 75 - Insulation layers

[0299] 15A - Surface

[0300] 20b, 30b, 40b - Main surfaces

[0301] 20z, 30z, 40z - Portions

[0302] 63A - Low density portion

[0303] 73A - Gap

[0304] 100 - Electrostatic chuck device

[0305] 103 - Substrate component

[0306] 104 - Adhesive layer

[0307] 115 - Fixing hole

[0308] 116 - Power supply terminal

[0309] 117 - Conductive adhesive layer

[0310] 118 - Through hole

[0311] 121 - Flow path

[0312] 122 - High-frequency power supply

[0313] 123 - Insulating material

[0314] 124 - DC power supply

[0315] 200 - Vacuum chamber

[0316] 300 - Upper electrode

[0317] 400 - Magnet

[0318] 500 - Gas supply mechanism

[0319] 600 - Vacuum pump

[0320] 700 - Plasma stabilization system

[0321] 710 - Detector

[0322] 720 - Control unit

[0323] 1000 - Semiconductor manufacturing apparatus

[0324] A, B - Positions

[0325] C - Center

[0326] CS1 - First curved surface

[0327] CS0 - Concave curved surface

[0328] CS2 - Second curved surface

[0329] G - Rotating magnet

[0330] L - Rotation axis

[0331] L1, L2, L3 - Widths

[0332] N - Normal

[0333] r1, r2, r0 - Curvature radii

[0334] S1, S2 - Virtual surfaces

[0335] T1, T2, T3 - Thicknesses

[0336] W1, W2 - Spacings

[0337] θ - Tilt

Claims

1. An electrostatic chuck component, comprising: a substrate having a mounting surface on one main surface for mounting a plate-shaped specimen; and an electrostatic adsorption electrode provided on the side opposite to the mounting surface or inside the substrate, on the side peripheral surface of the substrate continuous with the mounting surface, at least having: a first curved surface, which is a convex curved surface provided along the circumferential direction at the peripheral portion of the mounting surface; and a second curved surface, which is provided along the circumferential direction at a height position different from that of the first curved surface, near the outer edge of the electrostatic adsorption electrode, there is an electric field dispersion structure for dispersing the electric field at the outer edge of the electrostatic adsorption electrode.

2. The electrostatic chuck component according to claim 1, wherein the electric field dispersion structure is an electrode inclined surface provided at the outer edge portion of the electrostatic adsorption electrode and exposed to the view from the direction of the mounting surface and inclined.

3. The electrostatic chuck component according to claim 2, wherein the electrode inclined surface is a convex curved surface.

4. The electrostatic chuck component according to claim 1, wherein the electric field dispersion structure is a low-density portion provided at the outer edge portion of the electrostatic adsorption electrode, and the relative density of the low-density portion is lower than the relative density at the center of the electrostatic adsorption electrode.

5. The electrostatic chuck component according to claim 1, wherein the electric field dispersion structure is a gap provided between the outer edge of the electrostatic adsorption electrode and the inner edge of the substrate.

6. The electrostatic chuck component according to claim 1, wherein the side peripheral surface has a portion provided along the circumferential direction and extending outward at the lower end portion of the side peripheral surface, and the second curved surface is a concave curved surface provided on the upper surface of the extended portion.

7. The electrostatic chuck component according to claim 1, wherein the width of the electric field dispersion structure is greater than the thickness of the electrostatic adsorption electrode.

8. The electrostatic chuck component according to claim 1, wherein on the side peripheral surface, the inclined surface exposed to the view from the direction of the mounting surface is between the first curved surface and the second curved surface.

9. An electrostatic chuck device, comprising: the electrostatic chuck component according to any one of claims 1 to 8; and a base component for cooling the electrostatic chuck component and adjusting the temperature of the electrostatic chuck component.

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