Ceramic base

Abstract

The present invention relates to a ceramic susceptor, the ceramic susceptor of the present invention comprising a ceramic plate provided with an electrode, the ceramic plate comprising: an electrode pad connected to the electrode; and an electrode stem, one end of which is connected to the electrode pad and which supplies power to the electrode. The electrode stem may include: an extension portion connected to the electrode pad; and a power connection portion provided at an end portion of the tapering portion of the extension portion.

Description

Technical Field

[0001] The present invention relates to a pedestal, and more particularly, to a pedestal that applies an impedance-reducing electrode rod material in a ceramic-based pedestal.

[0002] In addition, the present invention relates to a pedestal, and more particularly, to a ceramic pedestal that improves the durability of an electrode rod. Background Art

[0003] Generally, a semiconductor device or a display device is manufactured by sequentially laminating a plurality of thin film layers including a dielectric layer and a metal layer on a glass substrate, a flexible substrate, or a semiconductor wafer substrate and then patterning them. In such a semiconductor manufacturing process, a pedestal is used as a support structure for supporting the substrate. For precise processes such as wiring miniaturization of semiconductor devices, the pedestal is widely used according to accurate temperature control and heat treatment requirements in a plasma deposition process or the like. In addition, the pedestal is used for plasma formation or substrate heating in an etching process of a thin film layer formed on a semiconductor wafer substrate.

[0004] Figure 1 It is a view for explaining an electrode portion of a conventional pedestal. Refer to Figure 1 , the conventional pedestal has a conductive pad 36 for bonding to electrode rods (31, 32) inside a ceramic plate 30. In the ceramic plate 30, a plurality of two-dimensional shapes (such as circular or semi-circular) radio-frequency (RF) electrodes 35 are buried. In addition, a conductive pad 36 electrically connected to the RF electrode 35 is buried.

[0005] An eyelet-shaped support 34 that internally accommodates the electrode rods (31, 32) is threadedly coupled to the ceramic plate through a thread formed in an opening of the ceramic plate 30. At this time, solder 37 can be provided between the upper electrode rod 31 and the lower electrode rod 32 and between the lower electrode rod 32 and the conductive pad 36, and the solder 37 can electrically connect the electrode rods (31, 32) and the RF electrode 35 through a joining process such as soldering. In the conventional pedestal as described above, a gap between the support 34 and the lower electrode rod 32 or a gap between the support 34 and the ceramic plate 30 serves as a path through which oxygen can permeate in a high-temperature atmosphere, thereby oxidizing the upper electrode rod 31 and the lower electrode rod 32. Through this oxidation, the conductivity and power transmission efficiency of the electrode rod are reduced, which may lead to a reduction in the reliability of the electrode portion and a problem of shortening the life of the pedestal.

[0006] Due to this oxidation problem, existing electrode rods mainly use heat-resistant and oxidation-resistant materials (such as Ni or Ni alloy materials). However, when the existing Ni series heat-resistant materials applied to electrode rods are used as power transmission lines in a high-frequency region, due to the skin effect of the current flowing along the surface of the electrode rod, the impedance of the electrode rod increases and is accompanied by heat generation.

[0007] Furthermore, with the development of semiconductor processes, a pedestal capable of applying high-frequency electricity with high conductivity is required to operate at higher temperatures and have higher plasma characteristics. Therefore, the skin effect in the electrode rod is more obvious, and short-circuit problems due to heat generation and oxidation occur frequently.

[0008] To improve the above problems, in the past, attempts have been made to reduce heat generation or reduce heat conduction by coating Au, Ag, Al, or Cu on the rod base materials of Ni or Ti as disclosed in Patent Publication No. 10-2018-0121662 (November 07, 2018), or by coating an alumina film on the rod base materials of Mo, Ni, Ti as disclosed in Patent Publication No. 10-2021-0139368 (November 22, 2021). However, even in such cases, the impedance problem of the electrode rod material that increases with the increase in frequency in high-frequency power transmission has not been fundamentally solved.

[0009] Figure 9 It is a diagram for explaining another electrode part of an existing ceramic pedestal.

[0010] Refer to Figure 9, the existing ceramic base has an electrode portion at the center of the ceramic plate 30 for bonding to external electrode rods (31, 32). In the ceramic plate 30, electrodes 35 that can serve as heating elements (electrodes) or RF (high-frequency) electrodes are buried in a ring shape, circular shape, etc. In addition, a conductive pad 36 serving as an electrode base material and electrically connected to the electrode 35 is buried. The eyelet-shaped support 34 is threadedly engaged through the threads formed in the opening, and the upper electrode rod 31 and the lower electrode rod 32 and between the lower electrode rod 32 and the conductive pad 36 are electrically connected by brazing to connect the electrode rods (31, 32) for power supply and the electrode 35. In the existing ceramic base as described above, the gap between the support 34 and the lower electrode rod 32 or the gap between the support 34 and the ceramic plate 30 forms a path through which oxygen can penetrate in a high-temperature atmosphere, thereby oxidizing the solder 37 formed on the interface between the conductive pad 36 serving as the electrode base material and the lower electrode rod 32, or the conductive pad 36 and the lower electrode rod 32. The solder formed on the interface between the upper electrode rod 31 and the lower electrode rod 32 can also be oxidized due to oxygen penetration. Through this oxidation, the conductivity and power transmission efficiency are reduced, and the reliability of the electrode portion may be reduced and there is a problem of shortening the life of the ceramic base.

[0011] To overcome this reliability problem, the existing electrode rods mainly use heat-resistant and oxidation-resistant materials (such as Ni or Ni alloy materials). Since the Ni material used in the existing electrode rods is a ferromagnetic material, when used as a power transmission line (such as an electrode) in a high-frequency region, the skin depth in the skin effect on the line where electrons are to move is small, making it difficult for electrons to move, increasing the impedance and generating heat, and causing a short circuit with the ceramic plate 30, etc.

[0012] In addition, in order to improve the above problem, the existing electrode rods use materials with low magnetic permeability such as Mo or apply an antioxidant coating to the rod material. However, even in this case, due to the interface thermal stress between the electrode rod metal materials such as Mo and the coating or the brittle characteristics of the coating material itself, etc., when used in a semiconductor process, the coating is damaged (cracked) or oxygen penetrates into the electrode rod metal materials as a result, so there is a problem of oxidation of the electrode rod metal materials. Summary of the Invention

[0013] Problems to be Solved by the Invention

[0014] The inventors of the present invention have noticed that Ni or Ni alloy materials, as ferromagnets, have a high relative magnetic permeability (<600). Therefore, when used as radio frequency (RF) rods, as the power and frequency increase, the skin depth within the electrode rod becomes extremely small according to the skin effect, making it difficult for electrons to move, and ultimately becoming a factor in increasing impedance. This increase in the impedance of the electrode rod not only becomes a reason for reducing plasma efficiency as the electrical energy consumed during the plasma discharge process is converted into heat energy and consumed at the end of the electrode rod, but also the heat generated in the electrode rod causes unevenness in the thickness and thin film quality of the thin film deposited on the substrate by forming a hot spot zone on the upper surface of the ceramic plate supporting the substrate, and thus can become a factor in reducing the yield rate.

[0015] In addition, as the temperature of the ceramic part in contact with the part fastened to the electrode rod rises rapidly locally, it becomes a decisive factor in generating an arc due to the destruction of the base and the damage of the brazing joint based on thermal shock. In order to increase the yield rate of semiconductor devices and improve the durability of the base, it is necessary to solve the impedance problem of the electrode rod.

[0016] Therefore, an object of the present invention is to provide a base provided with an electrode rod having low impedance and good high-frequency transmission characteristics for RF current.

[0017] In addition, an object of the present invention is to provide an electrode rod with a surface coating structure suitable for the aforementioned RF power transmission.

[0018] In addition, an object of the present invention is to provide an electrode rod with a surface coating structure that has resistivity against heat generated by the skin effect.

[0019] In addition, an object of the present invention is to provide an electrode rod with a surface coating structure that exhibits good brazing characteristics.

[0020] In addition, an object of the present invention is to provide a manufacturing method for the aforementioned electrode rod.

[0021] In addition, an object of the present invention is to provide a base provided with the aforementioned RF power transmission electrode rod.

[0022] In addition, an object of the present invention is to provide a base having a surface coating structure and provided with an integral electrode rod.

[0023] In addition, an object of the present invention is to improve the following problems: Even when the material of the electrode rod for the electrode is selected from Mo, W, or their alloys, and a substance with a high specific resistance (such as TiN, TiAlCrN, TiAlN, and AlCrN) is used as the coating, as Figure 9 shown, in the part where there is a step or a corner in the joint portion on the extension line of the electrode rod, due to the cracking of the coating, oxygen penetrates into the electrode rod metal material and causes oxidation of the electrode rod metal material, so oxides are concentratedly generated.

[0024] An object of the present invention for improving the above problems is to provide an electrode rod structure of a ceramic base that improves durability and has good high-frequency transmission characteristics in an antioxidant and corrosion-resistant environment, and to provide a ceramic base with a unique position or structure of the joint portion on the extension line of the electrode rod.

[0025] Means for Solving the Problem

[0026] To achieve the above technical problems, the present invention provides a base including a ceramic plate provided with an electrode. The base includes: an electrode rod, one end of which is electrically connected to the electrode and the other end is electrically connected to a power supply and is used to supply power to the electrode. The electrode rod includes: a base material, which is Mo, W, or an alloy of their metals; and a metal nitride film for wrapping the surface of the base material. In addition, in the present invention, one end of the electrode rod may include an exposed surface of the base material not covered by the metal nitride film.

[0027] In the present invention, the metal nitride film may include an AlCrN film. At this time, the Cr / (Al + Cr) molar ratio of the AlCrN film may be 0.1 to 0.9.

[0028] In addition, the metal nitride film may include one or more nitride films selected from the group consisting of AlCrSiN, AlCrSiWN, and AlTiCrN.

[0029] In the present invention, the ratio of the specific resistance of the metal nitride film to the specific resistance of the base material is preferably 10 2 or more, 10 3 or more, or 10 4 or more.

[0030] In the present invention, a CrN base layer may also be included between the base material and the metal nitride film.

[0031] In the present invention, the thickness of the metal nitride film may be 1.0 μm to 10.0 μm.

[0032] In order to solve the above technical problems, the present invention provides a base. In the base including a ceramic plate provided with electrodes, the base includes: an electrode rod assembly, one end of the electrode rod assembly is electrically connected to the electrode, and the other end is electrically connected to a power supply and is used for supplying power to the electrode. The electrode rod assembly includes a first rod and a second rod connected in series. The first rod includes: a base material, an alloy of Mo, W or their metals; and a metal nitride film for wrapping the surface of the base material.

[0033] In the present invention, the first rod and the second rod can be joined by a joining material.

[0034] In addition, preferably, the joint surface of the first rod and the second rod is an exposed surface of the base material not covered by the metal nitride film.

[0035] In the present invention, the first rod may include a base material made of Kovar.

[0036] In addition, according to another aspect of the present invention for achieving the above object, a base including a ceramic plate provided with electrodes, the ceramic plate includes: an electrode pad connected to the electrode; and an electrode rod, one side end of which is connected to the electrode pad and is used for supplying power to the electrode. The electrode rod includes: an extension part connected to the electrode pad; and a power supply connection part provided at the end of the tapered part of the extension part.

[0037] The electrode rod may include a metal nitride film on the surface of the base material.

[0038] The tapered part can be formed by taper machining on a machine tool so that the tapered part is included between the extension part and the power supply connection part with different diameters.

[0039] Relative to the length direction of the extension part, the inclination angle of the tapered part of the extension part can be 10° to 80°.

[0040] The length of the tapered part of the extension part in the length direction of the extension part can be 1.0 mm to 10.0 mm.

[0041] The position of the end with a smaller diameter in the tapered part of the extension part can be a position where the temperature is more than 10% lower than the lowest end face of the ceramic plate.

[0042] Preferably, the position of the end with a smaller diameter in the tapered part of the extension part can be a position where the temperature is more than 20% lower than the lowest end face of the ceramic plate.

[0043] The electrode rod may use Mo, W or their alloys as the base material.

[0044] The extension part of the electrode rod may include a second rod brazed and joined to the electrode pad and a first rod brazed and joined to the second rod.

[0045] Preferably, the second rod is made of a metal material with a difference in thermal expansion coefficient of 3 or less from the material of the electrode pad.

[0046] The electrode may be a high-frequency electrode, an electrostatic chuck electrode, or a heating element.

[0047] Advantages of the Invention

[0048] According to the first aspect of the present invention, the present invention can provide a base provided with an electrode rod having a low impedance and good high-frequency transmission characteristics for RF current.

[0049] In addition, according to the second aspect of the present invention, the electrode rod is coated on a resistive surface. When RF power is transmitted through the electrode rod, since the RF current flows to the base material in the surface coating, the heating part penetrates into the inner side of the surface coating of the electrode rod. Thus, the heating part is away from the surface of the electrode rod, and the possibility of reacting with oxygen in the atmosphere is reduced.

[0050] In addition, according to the third aspect of the present invention, an electrode rod with a surface coating structure suitable for RF power transmission can be provided.

[0051] In addition, according to the fourth aspect of the present invention, an electrode rod with a surface coating structure having resistance to heat generated by the skin effect can be provided.

[0052] In addition, according to the fifth aspect of the present invention, an electrode rod with a surface coating structure showing good brazing characteristics can be provided.

[0053] In addition, according to the sixth aspect of the present invention, a base provided with an RF power transmission electrode rod having the aforementioned characteristics can be provided.

[0054] In addition, according to the seventh aspect of the present invention, a base having a surface coating structure and provided with an integral electrode rod can be provided.

[0055] Moreover, according to the eighth aspect of the present invention, a ceramic base can be provided. In order for the electrode rod to receive power, the tapered part AA is placed at a position separated from the ceramic plate (especially at a position where the temperature is significantly reduced in the semiconductor process), and the shape of the joint part is designed to be streamline such as trapezoidal to avoid forming sharp corners, thereby improving the durability of the ceramic base and extending its service life, so that it has good high-frequency transmission characteristics even in an antioxidant and corrosion-resistant environment for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] To facilitate the understanding of the present invention, the accompanying drawings included as part of the detailed description provide embodiments of the present invention and, together with the detailed description, are used to illustrate the technical concept of the present invention.

[0057] Figure 1 It is a diagram for explaining the electrode portion of an existing base.

[0058] Figure 2A and Figure 2B are respectively a perspective view and a cross-sectional view schematically showing the outer shape of an electrode rod according to an embodiment of the present invention.

[0059] Figure 3 It is a diagram schematically showing a cross-section of the electrode rod structure according to another embodiment of the present invention.

[0060] Figure 4 It is a partial cross-sectional view schematically showing a base according to an embodiment of the present invention.

[0061] Figure 5 It is a cross-sectional view schematically showing the structure of a base according to another embodiment of the present invention.

[0062] Figure 6 It is a flowchart of the process for forming a metal nitride film on the electrode rod of a base according to an embodiment of the present invention.

[0063] Figure 7 It is a diagram showing the measurement results of power loss.

[0064] Figure 8 It is a graph plotting the measurement results of the resistance values before and after the oxidation treatment of each rod material.

[0065] Figure 9 It is a diagram for explaining another electrode portion of an existing ceramic base.

[0066] Figure 10A It is a diagram for explaining the structure of a ceramic base according to yet another embodiment of the present invention.

[0067] Figure 10B It is a diagram for explaining the structure of a ceramic base according to yet another embodiment of the present invention.

[0068] Figure 11 is Figure 10A and Figure 10B an enlarged view of the peripheral portion including the tapered portion AA between the extension portion and the power supply connection portion of the present invention in

[0069] Figure 12 It shows an embodiment in which the ceramic base of the present invention is provided in a process chamber of a semiconductor device.

[0070] Figure 13It is a flowchart of the film forming process for the electrode rod of the ceramic base for explaining an embodiment of the present invention.

[0071] Explanation of reference numerals

[0072] 1, 150: Electrode rod assembly

[0073] 10: Electrode rod

[0074] 10', 131: First rod

[0075] 12, 12': Base material

[0076] 22: Second base material

[0077] 24: Second metal nitride film

[0078] 20, 132: Second rod

[0079] 14, 14', 24, 141, 142: Metal nitride film

[0080] 100, 200: (Ceramic) base

[0081] 30, 110: Ceramic plate

[0082] 31: Upper electrode rod

[0083] 32: Lower electrode rod

[0084] 34: Support

[0085] 36: Conductive pad

[0086] 37: Solder

[0087] 35, 111: Electrode

[0088] 112: Electrode pad

[0089] 120: Support hole

[0090] 130: Extension

[0091] 133: Power connection part

[0092] 145: Bonding layer

[0093] 150: Electrode rod assembly

[0094] 151: First conductive filler

[0095] 152: Second conductive filler

[0096] 162: Brazing joint

[0097] 190: Opening

[0098] 191: Thread

[0099] 300: Process chamber

[0100] 310: Shaft

[0101] 320: Connecting bracket

[0102] A, B, C, D, E, F: Positions

[0103] AA: Tapered portion

[0104] BB: Lowest end face

[0105] E1, E2: Exposed surfaces

[0106] LL: Length

[0107] S: Joint

[0108] S110: Plasma pretreatment process

[0109] S120: Bonding layer formation process

[0110] S130: Reactive deposition process

[0111] PP: End

[0112] SS: Upper surface

[0113] w: Extension width

[0114] θ: Tilt angle Detailed implementation manners

[0115] Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. At this time, in each of the drawings, the same components are denoted by the same reference numerals as much as possible. In addition, detailed descriptions of well-known functions and / or structures are omitted. The content disclosed below focuses on the parts required to understand the operations of various embodiments, and descriptions of elements that make the gist of the description unclear are omitted. In addition, some components in the drawings may be enlarged or omitted, or schematically shown. The sizes of the respective components do not exactly reflect the actual sizes, and thus the content described here is not limited to the relative sizes or spacings of the components shown in each of the drawings.

[0116] In the process of describing the embodiments of the present invention, when it is determined that the specific description of the related well-known technologies of the present invention unnecessarily confuses the gist of the present invention, the detailed description thereof will be omitted. Moreover, the following terms are defined in consideration of the functions in the present invention and may be changed according to the intentions or conventions of users or operators. Therefore, the definitions should be based on the content of the entire specification. The terms used in the detailed description are only for describing the embodiments of the present invention and should not be restrictive. Unless otherwise clearly stated, the expression in the form of a single quantity includes the meaning of the form of multiple quantities. In the process of this specification, expressions such as "including" or "having" are used to indicate certain characteristics, numbers, steps, actions, elements, parts of these, or combinations, and should not be construed as excluding the existence or possibility of one or more other characteristics, numbers, steps, actions, elements, parts of these, or combinations other than those described.

[0117] In addition, terms such as "first", "second", etc. may be used to describe various components, but the components are not limited to these terms, and these terms are only for the purpose of distinguishing one component from other components.

[0118] In addition, in the specification of the present invention, the nitride film in "nitride film" or "metal nitride film" may be a nitride film of one metal element or a nitride film of two or more metal elements. In addition, in the specification of the present invention, the nitride film of metal element A may be expressed as A nitride film or AN. At this time, the expression "A nitride film or AN" can be used to refer to a binary metal element nitride film in which a part of metal element A is replaced or substituted by other metal elements, or a multi-metal element nitride film containing another metal element. Similarly, the binary metal element nitride film can be expressed as "nitride film of A and B", (A, B)N or ABN, and this expression can be used to refer to a ternary metal element nitride film or a multi-metal nitride film of more than ternary that contains additional metal elements in addition to A or B. For example, in the specification of the present invention, AlCrN can be used not only to mean including a binary nitride film, but also to mean including a ternary metal nitride film such as AlCrTiN.

[0119] In the specification of the present invention, the "electrical connection" of two components includes that the two components are directly in contact and electrically connected, or are electrically connected by placing one or more other components between the two components.

[0120] In addition, in the specification of the present invention, terms such as "above" or "on" of an object not only refer to the position directly in contact with the surface of the object, but also refer to the position where other components are placed in the middle without direct contact.

[0121] Figure 2A and Figure 2BThey are a perspective view and a cross-sectional view schematically showing the outer shape of an electrode rod according to an embodiment of the present invention, respectively.

[0122] Referring to Figure 2A and Figure 2B , the electrode rod 10 has a columnar shape extending along the length direction in a long strip shape. Figure 1 The shape of the electrode rod in [[ ]] is exemplary, and the present invention is not limited thereto, and the electrode rod may also be any shape such as a triangular prism or a quadrangular prism other than a cylinder. Additionally, in the drawings, the end of the electrode rod is planar, but it is not limited thereto, and at least one end of the electrode rod end may have a curved surface shape.

[0123] The electrode rod 10 includes a base material 12 and a metal nitride film 14 on the surface of the base material 12. In the present invention, the metal nitride film 14 may be in direct contact with the base material 12, or an additional material layer may be provided between the base material 12 and the metal nitride film 14.

[0124] In the present invention, preferably, the base material 12 has a low impedance and is paramagnetic. Exemplarily, the base material 12 may be made of Mo, W, or an alloy thereof that is paramagnetic.

[0125] As shown in the figure, a metal nitride film 14 is formed on the surface of the base material 12. The metal nitride film 14 extends along the outer peripheral surface in the length direction of the base material 12.

[0126] On the other hand, in the present invention, the metal nitride film 14 of the electrode rod 10 has a higher impedance than the base material 12, so it may be necessary to design a connection part for smoothly connecting the RF current of the electrode rod 10 with other components. For this purpose, in the present invention, one end of the electrode rod 10 may include an exposed surface E1 that is not coated with the metal nitride film 14. Additionally, the other end of the electrode rod 10 may include an exposed surface E2 that is not coated with the metal nitride film 14.

[0127] In the present invention, the exposed surfaces E1 and E2 of the electrode rod 10 can be better electrically connected to adjacent components. For example, as described below, the exposed surface E1 can be in direct contact with the conductive pad of the electrode, or can be electrically connected to the conductive pad through a conductive material layer (such as a bonding material). Additionally, the other exposed surface E2 can be electrically connected to an external power source.

[0128] In addition, in the present invention, on the exposed surface for electrical connection at one end of the electrode rod 10, that is, the exposed surfaces E1 and E2 of the electrode rod, can extend from the bottom surface to the side surface of the cylinder. At this time, the extension width w of the exposed surface can be appropriately designed. Of course, such an exposed surface extension portion can be provided at the other end of the electrode rod 10. In addition, the aforementioned extension portion of the exposed surface can be achieved by chamfering the end of the electrode rod 10.

[0129] In the present invention, preferably, the metal nitride film 14 may include a metal nitride film containing Cr. More preferably, the metal nitride film 14 may be a binary or ternary or higher metal nitride film containing Al and Cr. For example, the metal nitride film 14 may include at least one nitride film selected from the group consisting of AlCrN, AlCrSiN, AlCrSiWN, and AlTiCrN. In addition, in the present invention, the metal nitride film 14 may be a multilayer film in which layers of different compositions are laminated.

[0130] In the present invention, the metal nitride film 14 has a higher resistance than the base material 12. In the present invention, the specific resistances of Mo and W as the base material 12 are as shown in the following table.

[0131] Table 1

[0132] Distinction Specific Resistance (Ω·cm, @20℃) Mo <![CDATA[5.2*10 -6 > W <![CDATA[5.6*10 -6 >

[0133] In the present invention, preferably, the specific resistance (@20 °C) of the metal nitride film 14 is 1×10 -4 Ω·cm or less, 1×10 -3 Ω·cm or less, 1×10 -2 Ω·cm or less, 1×10 -1 Ω·cm or less, 1 Ω·cm or less, 1.5 Ω·cm or less, 2 Ω·cm or less, 5 Ω·cm or less, 10 Ω·cm or less, or 20 Ω·cm or less. On the other hand, the ratio of the specific resistance of the metal nitride film 14 to the specific resistance of the base material 12 may be 10 2 or more, 10 3 or more, 10 4 or more, or 10 5 or more.

[0134] In the description of the present invention, the specific resistance can be calculated by multiplying the surface resistance value obtained by multiplying the resistance value of the film measured by the four-point probe method by the correction factor (C.F) by the thickness of the film.

[0135] In the present invention, the metal nitride film 14 may further include one or more base layers. For example, the base layer may be a CrN base layer.

[0136] In the present invention, when the metal nitride film 14 is implemented as AlCrN, the specific resistance value of the metal nitride film 14 can be controlled by the relative contents of Al and Cr.

[0137] For example, in the composition of the metal nitride film 14 represented by Al 1-x Cr x N (where x is the atomic ratio), the specific resistance of the metal nitride film 14 can be controlled by controlling the atomic ratio (x) of Cr (i.e., Cr / (Al + Cr)).

[0138] The specific resistance of the CrN film formed by arc ion plating is 3*10 -4 Ω·cm. The specific resistance value can vary according to the contents of Al 1-x Cr x in N and the nitrogen concentration during the film formation process, etc. The AlCrN film with x≒0.2 - 0.8 formed by arc ion plating can have a value of 1 - 15 Ω·cm, and the AlCrN film with x≒0.5 can have a value of about 7 - 9 Ω·cm. In the present invention, the specific resistance can be adjusted according to the ratio of Al to Cr.

[0139] In the present invention, in order to achieve a preferable specific resistance value, the x value of the Al1 -x Cr x N film is preferably 0.1 or more, 0.15 or more, 0.2 or more, or 0.25 or more. Additionally, the x value is preferably 0.9 or less, 0.8 or less, 0.75 or less, 0.70 or less, 0.65 or less, 0.6 or less, 0.55 or less, or 0.5 or less.

[0140] In addition, the measured specific resistance values of various metal nitride films formed on the Al2O3 substrate are shown in Table 2 below.

[0141] Table 2

[0142] Film Composition Specific Resistance (Ω·cm) <![CDATA[Al 0.45 Cr 0.55 N]]> 7～9 CrN <![CDATA[3*10 -4 > AlCrSiWN <![CDATA[7*10 -1 <!-- 8 -->]]> AlCrSiN <![CDATA[1.54*10 -2 >

[0143] Figure 3 is a diagram schematically showing a cross-section of an electrode rod structure according to another embodiment of the present invention. Referring to Figure 3 , the electrode rod assembly 1 is provided with a first rod 10'. The first rod 10' includes a base material 12' and a metal nitride film 14' covering the surface of the base material. Additionally, exposed surfaces of the base material where the metal nitride film is not formed are formed at both ends of the first rod 10'. The base material 12' and the metal nitride film 14' can be made of the same materials as the electrode rod 10 described with reference to Figure 2A , Figure 2B .

[0144] On the other hand, a second rod 20 is coupled to the front end of the first rod 10'. The first rod 10' and the second rod 20 can be joined by a joint S. The joint S can be provided by welding or brazing an Au-Ni alloy joining material or an alloy joining material containing Ti at an appropriate temperature.

[0145] In the present invention, the second rod 20 may include a second base material 22 and a second metal nitride film 24 that wraps the second base material. Additionally, preferably, the second base material 22 at both ends of the second rod 20 is exposed.

[0146] In the present invention, the same materials as the (first) base material 12' and the (first) metal nitride film 14' can be used as the second base material 22 and the second metal nitride film 24.

[0147] Differently, the second base material 22 may include a metal of a different material from the (first) base material 12'. In this case, a metal or alloy having a thermal expansion rate similar to that of the electrode pad can be used as the second base material 22. For example, when Mo, W, or an alloy thereof is used as the electrode pad, an alloy with a low thermal expansion rate (such as Kovar) can be used as the second base material 22. At this time, when a nickel-based alloy (such as Kovar) is used as the second base material 22, the Figure 3 second metal nitride film 24 may not be provided.

[0148] In Figure 3 , the second rod 20 of the electrode rod assembly 1 can be electrically connected to the electrode pad, and the first rod 10' of the electrode rod assembly 1 can be electrically connected to an external power source. Of course, the opposite connection method is also possible.

[0149] Above, with reference to Figure 3 , the case where two electrode rods are connected in series to form an electrode rod assembly has been described, but the present invention is not limited thereto. For example, an electrode rod assembly composed of three or more electrode rods is also possible. Some or all of the electrode rods constituting these electrode rod assemblies may have an electrode rod structure as described Figure 2A , Figure 2B in relation to.

[0150] Figure 4 is a partial cross-sectional view schematically showing a base of an embodiment of the present invention.

[0151] With reference to Figure 4, the (ceramic) base 100 includes: a ceramic plate 110; an electrode 111 embedded in the ceramic plate 110; and an electrode pad 112 for electrically connecting the electrode 111. An opening 190 exposing the electrode pad is provided on the ceramic plate 110, and an electrode rod 10 is coupled to the opening 190. The electrode rod 10 supplies power (e.g., radio frequency (RF) power) to the electrode 111.

[0152] On the other hand, additionally, a support eyelet 120 for supporting the electrode rod 10 may be provided along the outer circumference of the electrode rod 10 within the opening 190. The support eyelet 120 may be threadedly coupled to the opening 190. To this end, a thread 191 is formed on a part of the inner circumferential surface of the opening 190, and correspondingly, a coupling structure (e.g., an external thread) for fastening to the thread 191 (e.g., an internal thread) may be provided on the outside of the support eyelet 120.

[0153] On the other hand, although not shown in the drawings, in the present invention, in addition to the electrode 111, the ceramic plate 110 may further include a heating element (not shown) for heating a substrate placed on the ceramic plate and an electrode pad for supplying power to the heating element. Therefore, in the present specification, although the structure of the electrode rod 10 of the electrode 111 is described, this structure may also be directly applied to the heating element (not shown) and the electrode rod for connecting the electrode rod.

[0154] In the present invention, the ceramic plate 110 may be configured to dispose (embed) the electrode 111 and / or a heating element (not shown) at a predetermined interval between ceramic materials. The ceramic plate 110 may be configured to be able to perform heating using the heating element (not shown) and / or a plasma enhanced chemical vapor deposition process using the electrode 111 while stably supporting a substrate to be processed. The ceramic plate 110 may be formed into a plate-like structure having a predetermined shape. As an example, the ceramic plate 110 may be formed into a circular plate-like structure, but is not limited thereto. Among them, the ceramic material may be at least one of Al2O3, Y2O3, Al2O3 / Y2O3, ZrO2, autoclaved lightweight concrete (AlC), TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, BxCy, BN, SiO2, SiC, YAG, mullite, and AlF3, and preferably, may be aluminum nitride (AlN).

[0155] An electrode pad 112 electrically connected to the electrode 111 is exposed in the opening 190 of the ceramic plate 110. The end connection surface of the electrode rod 10 is electrically connected to the electrode pad 112 in a coupling (e.g., welding or brazing) manner.

[0156] In the present invention, the electrode 111, the electrode pad 112, the support holes 120, the heating element (not shown), etc. can be formed of a conductive material (for example, tungsten (W), molybdenum (Mo), silver (Ag), copper (Cu), nickel (Ni), gold (Au), platinum (Pt), niobium (Nb), titanium (Ti), or an alloy thereof, etc.).

[0157] In the present invention, the electrode rod 10 has a low resistance, that is, it has a low impedance and is implemented as a paramagnetic body. As described above, the base material of the electrode rod 10 is made of paramagnetic Mo, W, or an alloy thereof. Therefore, compared with Ni or Ni alloy, the electrode rod 10 has a larger skin depth, and as a result, it exhibits improved impedance characteristics.

[0158] On the other hand, compared with Ni or Ni alloy, molybdenum, tungsten, and their alloys, which are the base materials of the electrode rod 10, exhibit the characteristic of being easily oxidized by reacting with oxygen. Therefore, since the base material heats up as the RF current is applied, the electrode rod 10 oxidizes and deteriorates.

[0159] To solve the problems described above, the present invention provides a metal nitride film on the surface of the base material of the electrode rod 10. Additionally, in the present invention, a metal nitride film is formed on the outer peripheral surface of the electrode rod 10, and no metal nitride film is formed at the end where the electrode rod 10 is connected to other components. Thus, the electrode rod 10 can provide good electrical connection with adjacent components while supplementing the antioxidant characteristics of the base material.

[0160] Furthermore, in the present invention, the electrode rod 10 has controlled electrical characteristics. In the present invention, the specific resistance and ratio of the metal nitride film to the metal base material can be controlled within an appropriate range.

[0161] Moreover, in the present invention, the metal nitride film can be appropriately designed according to the frequency and power of the RF current introduced into the electrode rod 10. When the RF power frequency increases, the skin depth of the base material decreases, and the heat generation amount on the surface of the base material can increase. In this case, preferably, the thickness of the metal nitride film is increased.

[0162] For example, when the RF power frequency introduced into the electrode rod 10 is 10 MHz, the skin depth of the Mo base material is approximately 38 μm, and when the RF power frequency is 100 MHz, the skin depth of the Mo base material is 12 μm.

[0163] In the present invention, in an environment where an RF power frequency of 10 MHz to 40 MHz is used (for example, 13.56 MHz, 27.12 MHz, etc.), the thickness range of the metal nitride film is preferably 4 μm to 10 μm.

[0164] In the present invention, one end of the electrode rod 10 can be joined to the electrode pad 112 by welding or brazing. For this purpose, a first conductive filler 151 for joining to the electrode pad 112 can be provided at one side end of the electrode rod 10.

[0165] In addition, a second conductive filler 152 for filling the space between the support hole 120 and the electrode rod 10 can be provided around the electrode rod 10 inserted inside the support hole 120. The first conductive filler 151 and the second conductive filler 152 can be provided by welding or brazing an Au-Ni alloy bonding material or an alloy bonding material containing Ti at an appropriate temperature.

[0166] In the present invention, the amounts of the first conductive filler 151 and the second conductive filler 152 can be appropriately controlled.

[0167] Figure 5 It is a cross-sectional view schematically showing the structure of a base according to another embodiment of the present invention.

[0168] Refer to Figure 5 , except that the electrode rod assembly 1 described relatedly in Figure 2A , Figure 2B is used instead of the electrode rod 10 in Figure 3 , the base 100 has substantially the same configuration. The electrode rod assembly 1 is provided with a first rod 10' and a second rod 20 of the brazing joint 162 described relatedly in Figure 2A , Figure 2B , and each configuration has been described in Figure 2A , Figure 2B , so the description thereof will be omitted. On the other hand, as described above, the second metal nitride film 24 may not be provided on the second rod 20.

[0169] Figure 6 It is a flowchart of a process for forming a metal nitride film on an electrode rod of a base according to an embodiment of the present invention. In this embodiment, the case of forming an AlCrN film using a metal nitride film is illustrated.

[0170] Refer to Figure 6 , in the present invention, various deposition methods can be used in the AlCrN formation process, for example, a physical vapor deposition (PVD) method such as arc ion plating.

[0171] As shown in the figure, the coating of the electrode rod 10 can be formed by including a plasma pretreatment process S110, a bonding layer formation process S120, and a reactive deposition process S130.

[0172] First, a plasma pretreatment process S110 is performed on the surface of the base material composed of Mo, W, or their alloys. In the plasma pretreatment process S110, the electrode rod base material 12 is loaded into an arc ion plating device or a sputtering device, and at a vacuum degree of 1×10 -5 Torr or less, the surface of the electrode rod base material 12 is cleaned by plasma pretreatment. This is to achieve the best coating of the bonding layer and the metal nitride film in the subsequent processes.

[0173] Next, the bonding layer formation process S120 aims to reduce the internal stress of the metal nitride film to be formed and facilitate good bonding. The bonding layer can include a metal such as Cr or its alloy. Preferably, the bonding layer can include Cr nitride or a nitride of a Cr alloy.

[0174] In the present invention, the bonding layer can be formed by arc ion plating or sputtering. For example, in an arc ion plating or sputtering device, a CrN layer with a thickness of 0.1 μm to 4.0 μm can be deposited on the surface of each electrode rod base material 12 as the bonding layer. At this time, a chromium (Cr) target can be pre-loaded in the arc ion plating or sputtering device, and while injecting nitrogen gas into the reactor, the CrN layer is formed on the surface of the electrode rod base material 12 by PVD at a specified vacuum degree.

[0175] In the reactive deposition process S130, an Al and Cr target or an Al-Cr alloy target is loaded into the arc ion plating device, and while injecting nitrogen gas into the reactor, the thickness of AlCrN is formed to be 1.0 μm to 10.0 μm by PVD at a vacuum degree of about 1×10 -2 Torr. Regarding the AlCr alloy target, it can be an AlCr alloy target containing aluminum (Al) and chromium (Cr) in a specified ratio (for example, 7:3 at%). On the contrary, when using an Al target and a Cr target, the ratio of Al / Cr can be adjusted by changing the current of each target.

[0176] As described above, the end of the base material can be appropriately masked to prevent the metal nitride film from forming at the ends of the electrode rods (10, 10'). For example, the end of the base material can be masked by providing an adhesive tape or a photoresist film at the end of the base material or using a fixture. On the contrary, the end of the electrode rod 10 where the metal nitride film is formed can be processed to expose the base material, thereby realizing the exposed surface of the electrode rod.

[0177] <Experimental Example 1: Specific Resistance Measurement Experiment of AlCrN Film>

[0178] Using alloy targets with different Al and Cr contents, an AlCrN film with an area of 30 mm × 30 mm and a thickness of 5 μm to 7 μm was formed on the surface of an Al2O3 substrate by arc ion plating. Energy dispersive spectroscopy (EDS) analysis was performed on the Al and Cr ratios of the AlCrN films formed for each target, and the specific resistance of the AlCrN films was measured by the four-point probe method using a Loresta-GP device from Mitsubishi Chemical Corporation. The specific resistance of the AlCrN films was 1 to 15 Ω·cm.

[0179] The EDS analysis results of each component and the composition ratios (at%) are shown in Table 3 below.

[0180] Table 3

[0181]

[0182] <Experimental Example 2: Measurement Experiment of RF Power Loss of Electrode Rods>

[0183] The RF power loss was measured by using rods of Φ4 × 330 mm with different materials and coating compositions. Ni rods, Mo rods, AlCrN / Mo rods, W rods, and AlCrN / W rods were used as the rods to be measured, and the composition of the AlCrN film used the #2 composition in Experimental Example 1.

[0184] Figure 7 is a graph showing the power loss measurement results. As Figure 6 shown, it can be confirmed that in the radio frequency (RF) power loss rate calculated based on the measured impedance values, compared with the loss rate of Ni, the loss rates of Mo or AlCrN / Mo with an AlCrN film on its surface, W or AlCrN / W with an AlCrN film on its surface are reduced by about 40%. From the above results, it can be seen that in terms of power loss, compared with Ni, the electrode rods of Mo, W, AlCrN / Mo, and AlCrN / W show excellent characteristics.

[0185] <Experimental Example 3: Oxidation Resistance Characteristics of Electrode Rods>

[0186] The oxidation resistance characteristics were confirmed according to the materials and coating compositions of the Φ2x330 mm electrode rods.

[0187] Mo, MoW, AlCrN / Mo, and AlCrN / MoW rods were used as the electrode rods. The AlCrN film used the #2 composition in Experimental Example 1.

[0188] Each rod was oxidized in a box furnace at a temperature of 700 °C for 10 hours. The resistance values of each rod before and after the oxidation treatment were measured. The measurement was carried out using a resistance meter (RM3545) of HIOKI Corporation under the condition of INT 10 mΩ.

[0189] Figure 8 It is a graph showing the measurement results of the resistance values of each rod material before and after the oxidation treatment.

[0190] From Figure 8 it can be confirmed that the resistance of each rod material increases due to the oxidation treatment. However, for the rods formed with the AlCrN film, it can be confirmed that the resistance change rate before and after the heat treatment is low and the resistance value is also low.

[0191] In addition, on the other hand, in the present invention, the base is a semiconductor device for processing various substrates to be processed (semiconductor wafers, glass substrates, flexible substrates, etc.). As described below, the semiconductor device is provided with an electrode 111, and the electrode 111 has the function of a high-frequency electrode to perform a process on the corresponding substrate to be processed, such as dry etching using plasma or plasma-enhanced chemical vapor deposition, etc. In addition, in order to support the corresponding substrate to be processed, the electrode 111 can also be used as a chuck electrode, and the chuck electrode is used as an electrostatic chuck. Furthermore, in the present invention, the base can also be provided with a heating wire (or heating element / heating electrode) for heating the corresponding substrate to be processed at a specified temperature.

[0192] The high-frequency electrode, electrostatic chuck electrode, heating wire, etc. of the electrode (or conductor) 111 can be composed of a conductive metal material (silver (Ag), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), titanium (Ti), etc. or their alloys, etc.). The electrode as the high-frequency electrode can receive power in a semiconductor manufacturing process and be able to perform a process on the substrate located on the upper surface of the base (such as plasma-enhanced chemical vapor deposition, etc.). In addition, the electrode as the electrostatic chuck electrode can receive a bias voltage of power in a semiconductor manufacturing process and generate an electrostatic force to clamp the substrate located on the upper surface of the base. When unloading the substrate, discharge can be achieved by receiving an opposite bias voltage to release the clamping. In addition, the heating wire (or heating element / heating electrode) can be formed in the form of a plate-shaped coil or a flat plate based on a resistance wire having a specified resistance, and in order to precisely control the temperature, it can also be formed in a multilayer structure. Such a heating wire (or heating element / heating electrode) can receive power and perform the function of heating the substrate located on the upper surface of the base to a constant temperature to perform a smooth deposition process and etching process in a semiconductor manufacturing process.

[0193] Therefore, hereinafter, in the present invention, the electrode 111 of the ceramic base is schematically illustrated as the high-frequency electrode for supplying high-frequency (RF) power through the electrode rod, but it is not limited thereto. It should be noted in advance in the present invention that even when the chuck electrode of the electrostatic chuck or an additional heating element is powered through the electrode rod, the relevant description of the electrode of the ceramic base can be similarly applied.

[0194] Hereinafter, with reference to the accompanying drawings ( Figures 10A to 13 ), another aspect of the present invention will be described. At this time, in each of the drawings, the same components are denoted by the same reference numerals as much as possible. In addition, even if they are not the same reference numerals, if the names of the components are the same, the components may be the same structure and may perform the same functions. In particular, the same components described in the description of Figures 2A to 8 can be additionally applied to Figures 10A to 13 , and the detailed description of the same functions and / or structures described above will be omitted. In addition, Figures 10A to 13 the same components described in the description of can also be additionally applied to Figures 2A to 8 .

[0195] Figure 10A is a view for explaining the structure of the ceramic base 100 according to still another embodiment of the present invention.

[0196] Referring to Figure 10A , the ceramic base 100 according to still another embodiment of the present invention may include a ceramic plate 110 provided with an electrode 111. Among them, the ceramic plate 110 may include: an electrode pad 112 connected to the electrode 111; and an electrode rod assembly 150, one end portion of which is connected to the electrode pad 112 and is used to supply power to the electrode 111. In this case, the electrode rod assembly 150 includes a first rod 131 and an extension portion 130 including a second rod 132.

[0197] That is, in Figure 10A , the electrode rod assembly 150 may include: an extension portion 130 connected to the electrode pad 112; and a power supply connection portion 133 provided at the end of the tapered portion AA of the extension portion 130. That is, the electrode rod assembly 150 includes an extension portion 130, which includes a first rod 131 and a second rod 132, and includes a tapered portion AA and a power supply connection portion 133 at the end of the extension portion 130.

[0198] In this case, the extension part 130 may include a first rod 131 and a second rod 132 brazed and joined 162 to the first rod 131. The second rod 132 may be made of a metal material with a difference in coefficient of thermal expansion from that of the material of the electrode pad 112 of 3 or less. For example, the coefficient of thermal expansion of the electrode pad 112, the first rod 131, and the power supply connection part 133 may be 4.5 to 5.6 μm / °C, and they may be made of Mo, W, or an alloy (MoW) material thereof. The coefficient of thermal expansion of the second rod 132 may be 4.9 to 6.2 μm / °C, and it may be made of an Fe-Ni-Co alloy (such as a Kovar product) material. The difference between the coefficient of thermal expansion of the second rod 132 and that of the first rod 131 including the power supply connection part 133 is preferably 3 or less.

[0199] Figure 10B FIG. is a diagram for explaining the structure of the ceramic base 200 according to another embodiment of the present invention. In this case, it is a case where one rod is connected to the electrode pad 112 and extends to the power supply connection part 133.

[0200] Refer to Figure 10B , the ceramic base 200 according to another embodiment of the present invention may include a ceramic plate 110 provided with an electrode 111. Among them, the ceramic plate 110 may include: an electrode pad 112 connected to the electrode 111; and an electrode rod assembly 150, one end of which is connected to the electrode pad 112 and is used to supply power to the electrode 111.

[0201] In this case, the electrode rod assembly 150 may include: a first rod (or extension part) 131 connected to the electrode pad 112; and a power supply connection part 133 provided at the end of the tapered part AA of the first rod (or extension part) 131. That is, the electrode rod assembly 150 includes a first rod (or extension part) 131 composed of one rod, and at the end of the first rod (or extension part) 131, there are a tapered part AA and a power supply connection part 133. Among them, for example, the coefficient of thermal expansion of the first rod (or extension part) 131 including the power supply connection part 133 may be 4.5 to 5.6 μm / °C, and it may be made of Mo, W, or an alloy material thereof.

[0202] That is, as Figure 10A and Figure 10B shown, the electrode rod assembly 150 of the present invention may include: an extension part (130, 131) connected to the electrode pad 112; and a power supply connection part 133 provided at the end of the tapered part AA of the extension part (130, 131).

[0203] In addition, the ceramic base 100 may include a support eyelet 120 combined with the electrode rod assembly 150. For example, the electrode rod assembly 150 may be combined with the support eyelet 120, and the support eyelet 120 may be fastened to the electrode 111 through the thread 191 of the ceramic plate 110.

[0204] On the other hand, as described above, although not shown in the drawings, in the present invention, the ceramic plate 110 may further include a heating element (electrode) (not shown) and a corresponding electrode rod. Therefore, although the structure related to the electrode rod assembly 150 of the electrode 111 is described in the present invention, it should be noted that this structure can also be directly applied to the heating element (electrode) (not shown) and the corresponding electrode rod.

[0205] That is, the ceramic plate 110 may be configured to have the electrodes 111 and / or the heating element (electrode) disposed (embedded) at a predetermined interval between the ceramic materials. The ceramic plate 110 is configured to stably support the substrate to be processed placed on its upper surface SS while being able to heat using the heating element (electrode) and / or serve as an electrostatic chuck for the electrode 111 or perform semiconductor processes using plasma, etc. The ceramic plate 110 may be formed into a plate-like structure having a predetermined shape. As an example, the ceramic plate 110 may be formed into a circular plate-like structure, but is not necessarily limited thereto. Among them, the ceramic material may be at least one of Al2O3, Y2O3, Al2O3 / Y2O3, ZrO2, Autoclaved lightweight concrete (AlC), TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, BxCy, BN, SiO2, SiC, YAG, Mullite, and AlF3, and preferably, it may be aluminum nitride (AlN). Furthermore, each ceramic powder may selectively contain about 0.1% to 10% of yttrium oxide powder, preferably contain about 1% to 5% of yttrium oxide powder or MgO, TiO2 powder, etc.

[0206] The electrode pad 112 is embedded in the ceramic plate 110 so that the electrode pad 112 is partially exposed at the bottom surface of a predetermined aperture portion of the ceramic plate 110. The end face of the electrode rod assembly 150 and the electrode pad 112 may be electrically connected by brazing.

[0207] The electrode 111, the electrode pad 112, the electrode rod assembly 150, the support hole 120, etc. may be composed of a conductor. For example, it may be formed of tungsten (W), molybdenum (Mo), silver (Ag), platinum (Pt), palladium (Pd), nickel (Ni), gold (Au), niobium (Nb), titanium (Ti), or their alloys, etc.

[0208] In particular, in the present invention, preferably, the electrode rod assembly 150 has a low impedance and is paramagnetic. Exemplarily, the electrode rod assembly 150 may be made of a base material of Mo, W, or their alloys, and an antioxidant coating is provided on the surface of the base material of the electrode rod assembly 150. As described above, for example, in Figure 10AIn [the above], the first rod 131 including the electrode pad 112 and the power connection part 133 can be made of Mo, W, or an alloy material thereof, and the second rod 132 can be made of an Fe-Ni-Co alloy (such as Kovar products) material. Additionally, for example, in Figure 10B In [the above], the coefficient of thermal expansion of the first rod (or extension part) 131 including the power connection part 133 can be 4.5 to 5.6 μm / °C, and it can be made of Mo, W, or an alloy material thereof.

[0209] In the present invention, preferably, the antioxidant coating can include metal nitride films 141 and 142. Exemplarily, the metal nitride film can include AlN, and more preferably, it can include TiN, TiAlCrN, TiAlN, and AlCrN. Thus, a ceramic base 100 can be provided, which has the thermal properties, electrical properties (magnetic properties), and mechanical properties required in the manufacturing and processing process environment of the ceramic base 100 and also has advantages in terms of workability and material cost.

[0210] In Figure 10A In the ceramic base 100 of the present invention having the structure of [the above], one side of the electrode rod assembly 150 is joined inside the support hole 120, and it can include a first rod 131 and a second rod 132 connected by brazing. The first rod 131 and the second rod 132 as the extension part 130 can be formed as an integrated one rod, but it can also be a structure in which the first rod 131 and the second rod 132 are joined as described above. One side end face of the second rod 132 can be brazed and joined through the electrode pad 112 and the first conductive filler 151, and the first rod 131 can be brazed and joined to the other side end face of the second rod 132 through the second conductive filler 152. For example, conductive fillers (151, 152) can use Au-Ni metal fillers, etc. Conductive filler (152) for filling the space between the support hole 120 and the rods (131, 132) can be provided around the rods (131, 132) inserted inside the support hole 120.

[0211] The electrode pad 112 can be made of Mo, W, or an alloy thereof. Since the second rod 132 is close to the electrode 111, heat loss and thermal stress are generated. To prevent heat loss and reduce cracks and the like caused by thermal stress, preferably, a metal material with a coefficient of thermal expansion difference of 3 or less from the material of the electrode pad 112 as described above is used. In particular, in the present invention, to prevent oxidation (corrosion), the surface of the electrode rod assembly 150 can include metal nitride films 141 and 142, that is, the surface of the second rod 132 can include the metal nitride film 141 and the surface of the first rod 131 can include the metal nitride film 142. Depending on the situation, the metal nitride film 141 may not be required on the surface of the second rod 132, but according to requirements, the metal nitride film 141 can also be formed on the surface of the second rod 132.

[0212] In addition, the electrode rod assembly 150 includes a power connection portion 133, which has a diameter different from that of the extension portions (131, 132, 130), extends from the end of the extension portion 130, and is formed by taper machining.

[0213] For each of the brazing joints as described above, first, the first conductive filler 151 is pre-injected into the bottom surface of the opening 190, that is, pre-injected around the exposed portion of the electrode pad 112. Then, the second rod 132 is pushed into the inside of the support hole 120 so that one end face of the second rod 132 is in close contact with the electrode pad 112. Next, the second conductive filler 152 is sufficiently injected above the other end face of the second rod 132, and after the one end face of the first rod 131 is in close contact above the injected second conductive filler 152, high-temperature heating and cooling are performed.

[0214] In Figure 10B In the ceramic base 200 of the present invention having the structure of, except for omitting the second rod 132, similarly to the method described above, one end face of the first rod or the extension portion 131 composed of one first rod 131 can be brazed and joined through the electrode pad 112 and the first conductive filler 151. A conductive filler (152) for filling the space between the support hole 120 and the rod 131 can be provided around the rod 131 inserted into the inside of the support hole 120.

[0215] By using the ceramic bases 100 and 200 of the present invention as described above, the power connection portion 133 of the electrode rod assembly 150 can be connected to a power source, and power can be supplied to the electrode 111 through the electrode pad 112, thereby performing a semiconductor process (such as dry etching using plasma or plasma-enhanced chemical vapor deposition, etc.) or the function of an electrostatic chuck. Also, the substrate to be processed in the semiconductor process (such as a semiconductor wafer, a glass substrate, a flexible substrate, etc.) can be heated by using the heat (or high frequency) generated in the heating element (electrode).

[0216] In particular, the electrode rod assembly 150 can be made of an alloy (e.g., MoW, MoNi, WNi, etc.) containing Mo, W, or more than one of them in a weight ratio (wt%) greater than that of other metal substances. To prevent oxidation (corrosion), metal nitride films 141 and 142 are included on the surface of the electrode rod assembly 150, thereby effectively preventing oxidation of the electrode rod assembly 150 and removing the factor of increasing impedance with use. By reducing changes such as the increase in impedance of the electrode rod assembly 150, the energy loss converted into heat energy in the electrode rod assembly 150 can be removed, so that electrical energy can be effectively consumed in plasma discharge. In addition, by reducing the heat generated in the electrode rod assembly 150, a hot-spot zone is not formed on the upper surface of the ceramic plate 110 for supporting the substrate. Therefore, the uniformity of the thickness and thin film quality of the thin film deposited on the substrate can be improved and the yield can be increased. In addition, by eliminating the temperature rise of the ceramic part in contact with the part fastened to the electrode rod assembly 150, the damage of the ceramic base 100 due to thermal shock can be reduced and the generation of arcs in the brazing joint can be reduced. Therefore, the reduction of the impedance change of the electrode rod assembly 150 in the present invention can provide a ceramic base 100 with improved durability and contribute to increasing the yield of semiconductor devices.

[0217] Figure 11 Yes Figure 10A And Figure 10B An enlarged view of the peripheral part 200 including the tapered part AA between the extension parts (130, 131) and the power supply connection part 133 of the present invention in

[0218] Refer to Figure 11 , as described above, a power supply connection part 133 is provided at the end of the tapered part AA of the extension parts (130, 131) of the electrode rod assembly 150. That is, the tapered part AA can be formed by taper machining of a machine tool so that the tapered part AA is included between the extension parts (130, 131) and the power supply connection part 133 with different diameters. The machine tool can include machining devices using various methods (milling machine, lathe, machining center (MCT), computer numerical control (CNC), laser, etc.).

[0219] In the present invention, the tapered portion AA of the electrode rod assembly 150 can be machined at the same inclination angle θ along the periphery of the corresponding cylindrical rods (130, 131). For example, the overall length of the electrode rod assembly 150 can be 250 mm to 400 mm, and the length LL of the tapered portion AA having a shape that gradually tapers from the extension portions (130, 131) toward the power supply connection portion 133 is preferably 1.0 mm to 10.0 mm along the length direction of the extension portions (130, 131).

[0220] In addition, with respect to the length direction of the extension portion 130, the inclination angle θ of the tapered portion AA of the extension portions (130, 131) can be 10° to 80°, and for a smoother streamline connection, it can be 45° or less, 40° or less, 35° or less, 30° or less, 25° or less, or 20° or less. More preferably, the inclination angle θ can be 12° to 16°. Thus, the cross-section in the length direction of the tapered portion AA of the extension portions (130, 131) can be in a trapezoidal shape.

[0221] In addition, the position of the end portion having a smaller diameter in the tapered portion AA of the extension portions (130, 131) can be determined as a specified position for improving oxidation resistance and corrosion resistance. The position of the end portion having a smaller diameter in the tapered portion AA of the extension portions (130, 131) can be, for example, when the ceramic plate 110 is started, that is, when the heating element (electrode) is operated (or, if there is no heating element, an external heater can be used), a position that is more than 10% lower than the temperature of the ceramic plate 110, that is, the temperature of the lowermost end surface of the ceramic plate 110 (refer to Figure 12 BB therein) (for example, 650 °C, 550 °C, 450 °C, etc.), and preferably, it can be a position that is more than 20% lower.

[0222] In the embodiment described below, the overall length of the electrode rod assembly 150 is about 330 mm, the diameter of the extension portions (131, 132) is 4.6 mm, the diameter of the power supply connection portion 133 is 4 mm, the length LL of the tapered portion AA is 2.5 mm, and the inclination angle θ is 13.7°. At this time, it was confirmed that a position that is 80% or less lower than the temperature of the lowermost end surface of the ceramic plate 110 (refer to Figure 12 BB therein) (for example, 650 °C, 550 °C, 450 °C, etc.) is located at a position more than 5 mm away from the lowermost end surface of the ceramic plate 110 (refer to Figure 12 BB therein).

[0223] That is, by placing the tapered portion AA at a position where the temperature is significantly reduced in the semiconductor process among the positions separated from the ceramic plate 110, oxidation or corrosion of the corresponding portion due to high temperature during the use of the brazing joint or deposition process can be prevented.

[0224] Figure 12 An embodiment is shown in which the ceramic base 100 of the present invention is disposed in the process chamber 300 of a semiconductor device.

[0225] Referring to Figure 12 , inside the process chamber 300 of a semiconductor device for performing semiconductor processes (such as plasma enhanced chemical vapor deposition), ceramic bases 100, 200 may be provided, and the ceramic bases 100, 200 may be supported by a shaft 310 having through holes inside and a predetermined connection bracket 320.

[0226] In the ceramic bases 100, 200, (multiple) electrode rods (130, 132) connected to (multiple) electrode pads 112 of the ceramic plate 110 may pass through the inside of the shaft 310 and through the connection bracket 320 and then extend to the outside of the process chamber 300. That is, the power connection portions 133 of the (multiple) electrode rods (130, 132) may extend to the outside of the process chamber 300, such that the periphery of the end PP of the power connection portion 133 is connected to the connection unit of the power supply to receive the required power supply.

[0227] In such a process chamber 300, by operating the heating element etc. of the ceramic plate 110, the ceramic plate 110 is started and its temperature reaches 650 °C, 550 °C and 450 °C respectively. And as a result of measuring the temperature at positions A, B, C, D, E and F while moving downward a predetermined interval each time from the position A outside the shaft 310 parallel to the lowermost end face BB, as shown in Table 4 below, it was confirmed that the temperature decrease was faster. The overall length of the electrode rod assembly 150 of the base sample used was about 330 mm, and the diameters of the extension portions (131, 132) were 4.6 mm, and the diameter of the power connection portion 133 was 4 mm. In addition, the length LL of the tapered end portion AA was 2.5 mm, and the inclination angle θ was 13.7°.

[0228] Table 4

[0229]

[0230] As shown in the above table, when the temperatures at the position A of the lowermost end face BB of the ceramic plate 110 are 650 °C, 550 °C and 450 °C respectively, the positions lower than this temperature by more than 10% are all shown as position C, and the positions lower than this temperature by more than 20% are all shown as position D. Therefore, in the above-described case, the positions of the ends with smaller diameters in the tapered portion AA of the extension portions (130, 131) may be set at positions C, D, E and F, preferably at positions D, E and F.

[0231] Accordingly, by positioning the tapered portion AA at a position more than 10% lower than the temperature of the ceramic plate 110, the oxidation resistance and corrosion resistance of the electrode rod assembly 150 can be improved.

[0232] As described above, in order for the electrode rod assembly 150 to receive power, the ceramic base 100 of the present invention can place the tapered portion AA at a position spaced apart from the ceramic plate 110 (in particular, a position where the temperature is significantly reduced in the semiconductor process), and design the shape of the tapered portion AA into a streamline shape such as a trapezoid to avoid forming sharp corners, thereby improving the durability of the ceramic base 100 and extending its service life, so that it can long-term have good high-frequency transmission characteristics even in an oxidation and corrosion-resistant environment.

[0233] Figure 13 It is a flowchart of a coating formation process of the electrode rod assembly 150 of the ceramic base 100 for explaining an embodiment of the present invention.

[0234] Referring to Figure 13 , first, in order for the electrode rod assembly 150 to form coatings respectively, in order to form metal nitride films 141 and 142 on the surface of the base material of the electrode rod assembly 150 made of Mo, W, or their alloys respectively, a physical vapor deposition (PVD) method such as arc ion plating can be used. As shown in the figure, the coating of the electrode rod assembly 150 can be formed by including a plasma pretreatment process S110, an adhesive layer 145 formation process S120, and a reactive deposition process S130.

[0235] First, in the plasma pretreatment process S110, before the adhesive layer 145 is formed, the base material of the electrode rod assembly 150 is loaded into an arc ion plating device or a sputtering device, and under a vacuum degree of 1×10 -5 Torr or less, the surface of the base material of the electrode rod assembly 150 is cleaned by plasma pretreatment. This is to obtain the best coating of the adhesive layer 145 and the metal nitride films 141 and 142 in the subsequent processes. Among them, the electrode rod assembly 150 can be a rod pre-formed with extensions (130, 131), the tapered portion AA, and a power connection portion 133.

[0236] Next, the adhesive layer formation process S120 is used to reduce the internal stress of the metal nitride films 141 and 142 and contribute to good bonding. The adhesive layer 145 can include a metal such as Cr or its alloy. Preferably, the adhesive layer can include a Cr nitride or a nitride of a Cr alloy.

[0237] In the present invention, the bonding layer 145 can be formed by arc ion plating or sputtering. For example, in an arc ion plating or sputtering apparatus, a CrN layer with a thickness of 0.1 μm to 4.0 μm can be deposited on the surface of the base material of the extension portions (130, 131) of each electrode rod assembly 150 as the bonding layer 145. At this time, a Cr target can be pre-loaded in the arc ion plating apparatus or sputtering apparatus, and while injecting nitrogen gas into the reactor, the CrN layer can be formed on the surface of the base material of the extension portions (130, 131) of the electrode rod assembly 150, that is, on the extension portions (130, 131) including the tapered portion AA of the electrode rod assembly 150 and the power connection portion 133, by PVD in a specified degree of vacuum.

[0238] In the reactive deposition process S130, an Al target and a Cr target can be pre-loaded in the arc ion plating apparatus or sputtering apparatus, or an AlCr alloy target, etc., can be loaded, and while injecting nitrogen gas into the reactor of the arc ion plating apparatus or sputtering apparatus, the thickness of the metal nitride films 141, 142 can be formed to be 1.0 μm to 10.0 μm by PVD at a vacuum degree of about 1×10 -2 Torr. The AlCr alloy target can be an AlCr alloy target containing aluminum (Al) and chromium (Cr) in a specified ratio (for example, 7:3 at%). Conversely, when the Al target and the Cr target are loaded and used, the ratio of Al to Cr required in the process of forming the metal nitride films 141, 142 can be adjusted by changing the current of each target.

[0239] As described above, in order for the electrode rod assembly 150 to receive power, the ceramic bases 100, 200 of the present invention can place the tapered portion AA at a position separated from the ceramic plate 110 (in particular, a position where the temperature significantly decreases in the semiconductor process), and design its shape into a streamline shape such as a trapezoid to avoid forming sharp corners, thereby improving the durability of the ceramic base 100 and extending its service life, so that it can long-term have good high-frequency transmission characteristics even in an antioxidant and corrosion-resistant environment.

[0240] As described above, in the present invention, it has been described through specific matters such as specific components and defined embodiments and drawings, but this is only provided for a more comprehensive understanding of the present invention. The present invention is not limited to the described embodiments, and various modifications and deformations can be made by those of ordinary skill in the technical field to which the present invention belongs without departing from the essential characteristics of the present invention. Therefore, the idea of the present invention should not be determined by the described embodiments, and not only the appended claims, but all technical ideas equivalent or having equivalent deformations to the claims should be interpreted as being included within the scope of the rights of the present invention.

Claims

1. A base comprising a ceramic plate provided with electrodes, wherein: The ceramic plate comprises: an electrode pad connected to the electrode, and An electrode rod, one end of which is connected to the electrode pad, and the electrode rod is used to supply power to the electrode; The electrode rod comprises: an extension portion connected to the electrode pad, and A power connection portion is provided at an end of the tapered portion of the extension portion.

2. The base according to claim 1, wherein: The electrode rod includes a metal nitride film on the surface of the base material.

3. The base according to claim 1, wherein: The tapered portion is formed by taper machining using a machine tool so that the tapered portion is included between the extension portion and the power connection portion having different diameters.

4. The base according to claim 1, wherein: The tapered portion of the extending portion has an inclination angle of 10° to 80° relative to the length direction of the extending portion.

5. The base according to claim 1, wherein: The length of the tapered portion of the extending portion is 1.0 mm to 10.0 mm in the longitudinal direction of the extending portion.

6. The base according to claim 1, wherein: The position of the end portion having a small diameter in the tapered portion of the extension portion is a position at which the temperature is 10% or more lower than that of the lowermost end surface of the ceramic plate.

7. The base according to claim 1, wherein: The position of the end portion having a small diameter in the tapered portion of the extension portion is a position at which the temperature is 20% or more lower than that of the lowermost end surface of the ceramic plate.

8. The base according to claim 1, wherein: The electrode rod uses Mo, W or their alloy as base material.

9. The base according to claim 1, wherein: The extension portion of the electrode rod includes a second rod brazed to the electrode pad and a first rod brazed to the second rod.

10. The base according to claim 9, wherein: The second rod is made of a metal material having a thermal expansion coefficient difference of 3 or less with that of the material of the electrode pad.

11. The base according to claim 1, wherein: The electrode is a high-frequency electrode, an electrostatic chuck electrode or a heating element.

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