Ceramic Susceptor

Abstract

A susceptor is provided that is equipped with an electrode rod having low impedance to RF current and good high frequency transmission characteristics. [Solution] The ceramic susceptor 100 of the present invention is a ceramic susceptor including a ceramic plate 110 on which an electrode 111 is arranged, the ceramic plate including an electrode pad 112 connected to the electrode, and an electrode rod having one side end connected to the electrode pad for supplying power to the electrode, the electrode rod including an extension portion 130 connected to the electrode pad, and a power connection portion 133 provided at the end of the tapered portion of the extension portion.

Description

[Technical field]

[0001] The present invention relates to a susceptor, and more particularly to a susceptor that utilizes electrode rod material to reduce impedance in a ceramic-based susceptor.

[0002] The present invention also relates to a susceptor, and more particularly to a ceramic susceptor having an electrode rod with improved durability. [Background technology]

[0003] In general, semiconductor devices or display devices are manufactured by sequentially stacking 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 the layers. In the semiconductor manufacturing process, a susceptor is used as a holding structure for holding the substrate. Susceptors are widely used in plasma deposition processes and the like, which are required for precise temperature control and heat treatment for precision processes such as fine wiring of semiconductor devices, and are also used for plasma generation or substrate heating in etching processes of thin film layers formed on semiconductor wafer substrates.

[0004] Fig. 1 is a diagram for explaining an electrode portion of a conventional susceptor. Referring to Fig. 1, the conventional susceptor has a conductive pad 36 for coupling with electrode rods 31 and 32 inside a ceramic plate 30. RF electrodes 35 having various two-dimensional shapes such as a circular or crescent shape are embedded in the ceramic plate 30. Also, a conductive pad 36 electrically connected to the RF electrode 35 is embedded.

[0005] The eyelet-shaped support 34, which houses the electrode rods 31 and 32 therein, is screwed into the ceramic plate 30 through a thread formed in an opening of the ceramic plate 30. At this time, a brazing filler 37 may 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 brazing filler 37 can electrically connect the electrode rods 31 and 32 to the RF electrode 35 by a joining process such as brazing. In such a conventional susceptor, the gap between the support 34 and the lower electrode rod 32 or the gap between the support 34 and the ceramic plate 30 acts as a path through which oxygen can penetrate in a high-temperature atmosphere, and may oxidize the upper electrode rod 31 and the lower electrode rod 32. If the electrical conductivity of the electrode rods is reduced by such oxidation, and the power transmission efficiency is reduced, this may lead to a decrease in the reliability of the electrode part, and there is a problem in shortening the life of the susceptor.

[0006] Due to this oxidation problem, heat-resistant and oxidation-resistant materials such as Ni and Ni alloys have been used in conventional electrode rods. However, when the Ni-based heat-resistant materials used in conventional electrode rods are used as power transmission lines in the high-frequency range, the impedance of the electrode rod increases due to the skin effect, where current flows along the surface of the electrode rod, and heat is generated.

[0007] Furthermore, with the development of semiconductor processes, there is a demand for susceptors that can operate at higher temperatures and accept high-power radio frequency waves to have higher plasma characteristics. As a result, the skin effect in the electrode rods becomes more noticeable, and problems such as short circuits due to heat generation and oxidation occur frequently.

[0008] To improve this, in the past, attempts were made to reduce heat generation or thermal conduction by coating a Ni or Ti rod base material with Au, Ag, Al, or Cu as in Korean Patent Publication No. 10-2018-0121662 (2018.11.07), or by coating a Mo, Ni, or Ti rod base material with an alumina thin film as in Korean Patent Publication No. 10-2021-0139368 (2021.11.22). However, even in such cases, the problem of increased impedance of the electrode rod material due to increased frequency in high-frequency power transmission has not been fundamentally resolved.

[0009] FIG. 9 is a diagram for explaining another electrode portion of a conventional ceramic susceptor.

[0010] 9, the conventional ceramic susceptor has an electrode portion for connection with external electrode rods 31, 32 at the center of a ceramic plate 30. An electrode 35, which can be a heating element (electrode) or an RF (radio frequency) electrode, is embedded in the ceramic plate 30 in a ring or circle shape, and a conductive pad 36, which is an electrode base material electrically connected to the electrode 35, is embedded in the ceramic plate 30. An eyelet-shaped support 34 is screwed with a thread formed in an opening, and the upper end electrode rod 31 and the lower end electrode rod 32, and the lower end electrode rod 32 and the conductive pad 36 are brazed to electrically connect the electrode rods 31, 32 and the electrode 35 for power supply. In such a conventional ceramic susceptor, the gap between the support 34 and the lower end electrode rod 32 or the gap between the support 34 and the ceramic plate 30 creates a path through which oxygen can penetrate in a high-temperature atmosphere, oxidizing the brazing filler 37 formed at the interface between the conductive pad 36, which is the electrode base material, and the lower end electrode rod 32, or the conductive pad 36 and the lower end electrode rod 32. The brazing filler formed at the interface between the upper end electrode rod 31 and the lower end electrode rod 32 may also be oxidized by oxygen penetration. If the electrical conductivity is reduced by such oxidation and the power transmission efficiency is reduced, this may lead to a decrease in the reliability of the electrode portion, and there has been a problem of shortening the life of the ceramic susceptor.

[0011] In order to overcome such reliability problems, conventional electrode rods have mainly been made of heat-resistant and oxidation-resistant materials such as Ni or Ni alloys. The Ni material used in conventional electrode rods is a ferromagnetic material, so when used as a power transmission line in a high frequency range, such as for use in electrodes, the skin effect reduces the skin depth in the line through which electrons move, making it difficult for electrons to move, and therefore generates impedance and heat, resulting in a short circuit with the ceramic plate 30, etc.

[0012] To solve this problem, conventional electrode rods have been made of a material with low magnetic permeability, such as Mo, or a coating film has been applied to prevent oxidation of the rod material. However, even in these cases, thermal stress at the interface between the electrode rod metal material, such as Mo, and the coating film or the brittleness of the coating material itself can cause the coating film to crack during use in semiconductor processes, resulting in oxygen penetration into the electrode rod metal material, and this can cause the oxidation of the electrode rod metal material to progress. Summary of the Invention [Problem to be solved by the invention]

[0013] The inventors of the present invention have noticed that since Ni or Ni alloy material is a ferromagnetic material and has a high relative magnetic permeability (<600), when it is used as an RF (Radio Frequency) rod, the power and frequency increase, and the skin effect makes the skin depth in the electrode rod extremely small, making it difficult for electrons to move, resulting in an increase in impedance. This increase in the impedance of the electrode rod not only reduces the plasma efficiency by converting the electrical energy that should be consumed for plasma discharge into thermal energy at the end of the electrode rod and consuming it, but also causes a hot-spot zone to form on the surface of the upper end of the ceramic plate that holds the substrate, which leads to variations in the thickness and quality of the thin film deposited on the substrate, thereby reducing the yield.

[0014] In addition, the temperature of the ceramic portion where the electrode rod is attached rises suddenly in a localized area, which is a decisive factor in the destruction of the susceptor due to thermal shock and the generation of an arc due to damage to the brazing joint. Therefore, the impedance problem of the electrode rod must be solved in order to increase the yield of semiconductor devices and improve the durability of the susceptor.

[0015] Therefore, an object of the present invention is to provide a susceptor having an electrode rod that has low impedance to RF current and good high frequency transmission characteristics.

[0016] Another object of the present invention is to provide an electrode rod having the above-mentioned surface coating structure suitable for RF power transmission.

[0017] Another object of the present invention is to provide an electrode rod having a surface coating structure that is resistant to heat generation caused by the skin effect.

[0018] Another object of the present invention is to provide an electrode rod having a surface coating structure that exhibits good brazing characteristics.

[0019] Another object of the present invention is to provide a method for manufacturing the above-mentioned electrode rod.

[0020] Another object of the present invention is to provide a susceptor including the above-mentioned electrode rod for RF power transmission.

[0021] It is another object of the present invention to provide a susceptor having a surface coating structure and an integral electrode rod.

[0022] In addition, in the present invention, even when the material of the electrode rod for the electrode is selected from Mo, W or alloys thereof, and a material with high resistivity such as TiN, TiAlCrN, TiAlN, AlCrN is used for the coating film, as shown in FIG. 9, at the joint portion on the extension line of the electrode rod where there is a step or corner, cracks in the coating film cause oxygen to penetrate into the metal material of the electrode rod, and oxidation of the metal material of the electrode rod progresses, resulting in the generation of oxides in a concentrated manner. This is a problem that the present invention aims to solve.

[0023] An object of the present invention to make the above improvements is to provide a ceramic susceptor having a unique position and structure of the joint on the extension of the electrode rod, in order to provide an electrode rod structure of a ceramic susceptor having improved durability so as to have good high-frequency transmission characteristics in an oxidation-resistant and corrosion-resistant environment. [Means for solving the problem]

[0024] In order to achieve the above technical objectives, the present invention provides a susceptor including a ceramic plate on which an electrode is arranged, the susceptor including an electrode rod having one end electrically connected to the electrode and the other end electrically connected to a power source for supplying power to the electrode, the electrode rod including a base material of Mo, W or an alloy of these metals, and a metal nitride film covering a surface of the base material. Also, in the present invention, one end of the electrode rod includes an exposed surface of the base material that is not covered by the metal nitride film.

[0025] In the present invention, the metal nitride film may include an AlCrN film, in which the Cr / (Al+Cr) molar ratio may be 0.1 to 0.9.

[0026] The metal nitride film may include at least one nitride film selected from the group consisting of AlCrSiN, AlCrSiWN, and AlTiCrN.

[0027] In the present invention, the ratio of the resistivity of the metal nitride film to the resistivity of the base material is 10 2 That's it, 10 3 More than or equal to 10 4 More preferably, it is equal to or greater than this.

[0028] In the present invention, a CrN underlayer may be further included between the base material and the metal nitride film.

[0029] In the present invention, the metal nitride film may have a thickness of 1.0 to 10.0 μm.

[0030] In order to achieve the above technical objectives, the present invention provides a susceptor including a ceramic plate on which an electrode is disposed, and an electrode rod assembly having one end electrically connected to the electrode and the other end electrically connected to a power source for supplying power to the electrode, the electrode rod assembly including a first rod and a second rod connected in series, the first rod including a base material of Mo, W or an alloy of these metals, and a metal nitride film covering a surface of the base material.

[0031] In the present invention, the first rod and the second rod may be joined by a joining material.

[0032] Also, it is preferable that the joint surfaces of the first rod and the second rod are exposed surfaces of the base material that are not covered with a metal nitride film.

[0033] In the present invention, the first rod may include a base material made of Kovar.

[0034] In accordance with another aspect of the present invention for achieving the above object, a susceptor including a ceramic plate on which an electrode is disposed includes an electrode pad connected to the electrode, and an electrode rod having one side end connected to the electrode pad for supplying power to the electrode, the electrode rod including an extension portion connected to the electrode pad, and a power supply connector provided at an end of a tapered portion of the extension portion.

[0035] The electrode rod may include a metal nitride film on a surface of a base material.

[0036] The tapered portion may be formed by tapering using a machine tool such that the tapered portion is between the extension portion and the power connection portion, the diameters of which are different.

[0037] The tapered portion of the extension may have an inclination angle of 10° to 80° with respect to the longitudinal direction of the extension.

[0038] The tapered portion of the extension may have a length of 1.0 mm to 10.0 mm in the longitudinal direction of the extension.

[0039] The position of the smaller diameter end of the tapered portion of the extension may be at a position that is 10% or more lower than the temperature of the lowermost surface of the ceramic plate.

[0040] Preferably, the position of the smaller diameter end of the tapered portion of the extension may be at a position that is 20% or more lower than the temperature of the lowermost end surface of the ceramic plate.

[0041] The electrode rod may have a base material of Mo, W or an alloy thereof.

[0042] The extension of the electrode rod may include a second rod brazed to the electrode pad and a first rod brazed to the second rod.

[0043] The second rod is preferably made of a metal material having a thermal expansion coefficient difference of 3 or less with respect to the material of the electrode pad.

[0044] The electrode may be a radio frequency electrode, an electrostatic chuck electrode, or a heating element. Effect of the Invention

[0045] According to a first aspect of the present invention, it is possible to provide a susceptor including an electrode rod having low impedance to an RF current and good high-frequency transmission characteristics.

[0046] According to the second aspect of the present invention, the electrode rod is provided with a resistive surface coating, so that when RF power is transmitted through the electrode rod, RF current flows through the base material in the surface coating, causing the heat generating portion to penetrate inside the surface coating of the electrode rod, which moves the heat generating portion away from the surface of the electrode rod and reduces the possibility of the heat generating portion reacting with oxygen in the atmosphere.

[0047] Furthermore, according to the third aspect of the present invention, it is possible to provide an electrode rod having a surface coating structure suitable for RF power transmission.

[0048] Furthermore, according to the fourth aspect of the present invention, it is possible to provide an electrode rod having a surface-coated structure that has resistance to heat generation caused by the skin effect.

[0049] Furthermore, according to the fifth aspect of the present invention, it is possible to provide an electrode rod having a surface coating structure that exhibits good brazing characteristics.

[0050] Furthermore, according to a sixth aspect of the present invention, it is possible to provide a susceptor including an electrode rod for RF power transmission having the above-mentioned characteristics.

[0051] Furthermore, according to the seventh aspect of the present invention, it is possible to provide a susceptor that is provided with a surface coating structure and an integrated electrode rod.

[0052] According to an eighth aspect of the present invention, a ceramic susceptor having improved durability and lifespan and excellent high frequency transmission characteristics for a long period of time even in an oxidation-resistant and corrosion-resistant environment can be provided by positioning a tapered portion AA at a position where the electrode rod is separated from the ceramic plate to receive power, particularly at a position where the temperature drops significantly during a semiconductor process, and designing the shape of the joint to be a streamlined shape such as a trapezoid so as not to form a steeply inclined edge.

[0053] The accompanying drawings, which are included as part of the detailed description to aid in understanding the present invention, provide examples according to the present invention and, together with the detailed description, explain the technical concept of the present invention. [Brief description of the drawings]

[0054] [Figure 1] FIG. 1 is a diagram for explaining an electrode portion of a conventional susceptor. [Figure 2A] FIG. 1 is a perspective view showing a schematic external shape of an electrode rod according to an embodiment of the present invention. [Figure 2B] FIG. 2 is a cross-sectional view showing a schematic external shape of an electrode rod according to an embodiment of the present invention. [Diagram 3] FIG. 13 is a schematic cross-sectional view of an electrode rod structure according to another embodiment of the present invention. [Figure 4] FIG. 2 is a cross-sectional view showing a schematic view of a part of a susceptor according to an embodiment of the present invention. [Diagram 5] FIG. 4 is a cross-sectional view illustrating a schematic structure of a susceptor according to another embodiment of the present invention. [Figure 6] 4A to 4C are diagrams showing a procedure for forming a metal nitride film on an electrode rod of a susceptor according to an embodiment of the present invention. [Figure 7] FIG. 13 is a diagram showing the results of power loss measurements. [Figure 8] 1 is a graph plotting the resistance measurement results before and after oxidation treatment for each rod material. [Figure 9] FIG. 13 is a diagram for explaining another electrode portion of a conventional ceramic susceptor. [Figure 10A] 11A to 11C are diagrams illustrating the structure of a ceramic susceptor according to still another embodiment of the present invention. [Figure 10B] 11A to 11C are diagrams illustrating the structure of a ceramic susceptor according to still another embodiment of the present invention. [Figure 11] FIG. 13 is an enlarged view of the periphery of the present invention, including the tapered portion (AA) between the extension and the power connection of FIGS. 10A and 10B. [Figure 12] 1 is a view showing an embodiment in which a ceramic susceptor according to the present invention is installed in a process chamber of a semiconductor device. [Figure 13] 4 is a flowchart illustrating a process for forming a coating on an electrode rod of a ceramic susceptor according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0055] The present invention will be described in detail below with reference to the accompanying drawings. Here, the same components in each drawing are assigned the same reference numerals as much as possible. Also, detailed description of already known functions and / or configurations will be omitted. The contents disclosed below will be described with emphasis on parts necessary for understanding the operation of various embodiments, and description of elements that may make the gist of the description unclear will be omitted. Also, some components in the drawings may be exaggerated, omitted, or illustrated in outline. The size of each component does not entirely reflect the actual size, and therefore the contents described herein are not limited by the relative sizes and intervals of the components depicted in each drawing.

[0056] When describing the embodiments of the present invention, if it is determined that a detailed description of a known technology related to the present invention may make the gist of the present invention unclear, the detailed description will be omitted. The terms described below are defined in consideration of the functions in the present invention, and may be changed according to the intention or practice of the user or operator. Therefore, the definitions should be based on the entire contents of this specification. The terms used in the detailed description are merely for describing the embodiments of the present invention and should not be limiting in any way. Unless otherwise specified, expressions in the singular form include the plural form. In this description, expressions such as "include" or "comprise" are intended to indicate certain features, numbers, steps, operations, elements, parts thereof, or combinations thereof, and should not be interpreted to exclude the presence or possibility of one or more features, numbers, steps, operations, elements, parts thereof, or combinations other than those described.

[0057] In addition, terms such as first, second, etc. may be used to describe various components, but these terms are not intended to limit the various components, and these terms are only used for the purpose of distinguishing one component from another component.

[0058] In the present specification, the nitride film in the "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 the present specification, the nitride film of the metal element A may be expressed as A nitride film or AN. In this case, the expression A nitride film or AN may refer to a nitride film of a binary metal element in which a part of the metal element A is replaced or substituted with another metal element, or a nitride film of a multi-element metal element including another metal element. Similarly, the nitride film of a binary metal element may be expressed as "a nitride film of A and B", (A,B)N or ABN, and this expression may refer to a nitride film of a ternary metal element including an additional metal element in addition to A or B, or a multi-element metal nitride film of ternary or more elements. For example, in the present specification, AlCrN may be used to mean a binary nitride film as well as a ternary metal nitride film such as AlCrTiN.

[0059] In the present specification, "electrical connection" of two components includes whether the two components are electrically connected in direct contact with each other or are electrically connected with one or more other components interposed between them.

[0060] In addition, in the present specification, terms such as "above" or "on" an object are used to refer not only to a position that is in direct contact with the surface of the object, but also to a position that is not in direct contact with the surface of the object through another component.

[0061] 2A and 2B are respectively a perspective view and a cross-sectional view showing a schematic external shape of an electrode rod according to an embodiment of the present invention.

[0062] 2A and 2B, the electrode rod 10 has a shape of a long and thin column extending in the longitudinal direction. Here, the shape of the electrode rod is merely an example, and the present invention is not limited thereto, and the electrode rod may have any shape such as a triangular prism or a rectangular prism in addition to a cylindrical shape. In addition, although the ends of the electrode rod in the figures are flat, the present invention is not limited thereto, and at least one of the ends of the electrode rod may of course have a curved shape.

[0063] The electrode rod 10 includes a base material 12 and a metal nitride film 14 on a surface of the base material 12. In the present invention, the metal nitride film 14 may be in direct contact with the base material, or an additional layer of material may be interposed between the base material and the metal nitride film 14.

[0064] In the present invention, the base material 12 has low impedance and is preferably a paramagnetic material. For example, the base material 12 may be made of Mo, W, or an alloy thereof, which are paramagnetic materials.

[0065] 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 circumferential surface in the longitudinal direction of the base material.

[0066] Meanwhile, in the present invention, since the metal nitride film 14 of the electrode rod has a higher impedance than the base material, it may be necessary to design a connection part for smooth connection of RF current between the electrode rod and 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 covered by the metal nitride film 14. In addition, the other end of the electrode rod 10 may include an exposed surface E2 that is not covered by the metal nitride film 14.

[0067] In the present invention, the exposed surfaces E1 and E2 of the electrode rod 10 can provide better electrical connection with adjacent components. For example, as described below, the exposed surface E1 can be in direct contact with a conductive pad of an electrode or can provide electrical connection to the conductive pad via a conductive material layer such as an adhesive. The other exposed surface E2 can provide electrical connection to an external power source.

[0068] In addition, in the present invention, the exposed surfaces E1, E2 for electrical connection at one end of the electrode rod 10 may extend from the bottom surface of the cylinder to the side surface. In this case, the extension width w of the exposed surfaces may be appropriately designed. It is of course that such an extension of the exposed surfaces may be provided at the other end of the electrode rod 10. It is of course that the extension of the exposed surfaces described above may be realized by chamfering the end of the electrode rod.

[0069] In the present invention, the metal nitride film may preferably include a metal nitride film containing Cr. More preferably, the metal nitride film may be a binary or ternary or more metal nitride film containing Al and Cr. For example, the metal nitride film may include at least one nitride film selected from the group consisting of AlCrN, AlCrSiN, AlCrSiWN, AlTiCrN, etc. Also, in the present invention, the metal nitride film may be a multilayer film in which layers of different compositions are stacked.

[0070] In the present invention, the metal nitride film has a higher resistance than the base material. In the present invention, the resistivities of Mo and W as the base materials are as shown in the table below.

[0071] [Table 1]

[0072] In the present invention, the resistivity (@20°C) of the metal nitride film is preferably 1*10 -4 Ω cm or less, 1*10 -3 Ω cm or less, 1*10 -2 Ω cm or less, 1*10 -1 It is preferably 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.

[0073] On the other hand, the ratio of the resistivity of the metal nitride film to the resistivity of the base material is 10 2 That's it, 10 3 That's it, 10 4 More than or equal to 105 It may be more than that.

[0074] In the present specification, the resistivity may be calculated by multiplying the surface resistivity obtained by multiplying the resistance value of the film measured by the 4-point probe method by a correction factor (CF) and multiplying the surface resistivity by the thickness of the film.

[0075] In the present invention, the metal nitride film may further include one or more underlayers, for example, the underlayer may be a CrN underlayer.

[0076] In the present invention, when the metal nitride layer is embodied as AlCrN, the resistivity of the metal nitride layer may be controlled by the relative content of Al and Cr.

[0077] For example, Al 1-x Cr x The resistivity of the metal nitride film may be controlled by controlling the atomic ratio (x) of Cr in the composition of the metal nitride film expressed by N (where x is the atomic ratio), that is, Cr / (Al+Cr).

[0078] The CrN film formed by arc ion plating is 3*10 -4 The resistivity is shown in Ωcm. 1-x Cr x The resistivity may vary depending on the content of Al and Cr in N and the nitrogen concentration during the film formation process. An AlCrN film with x ≈ 0.2-0.8 formed by arc ion plating may have a resistivity of 1-15 Ω cm, and an AlCrN film with x ≈ 0.5 may have a resistivity of about 7-9 Ω cm. In the present invention, it is possible to adjust the resistivity by the ratio of Al and Cr.

[0079] In the present invention, in order to achieve a preferable resistivity value, Al 1-x Cr xThe x value of the N film is preferably 0.1 or more, 0.15 or more, 0.2 or more, or 0.25 or more, and 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.

[0080] In addition, the resistivity measurements of various metal nitride films formed on Al2O3 substrates are summarized in Table 2 below.

[0081] [Table 2]

[0082] FIG. 3 is a schematic cross-sectional view of an electrode rod structure according to another embodiment of the present invention.

[0083] 3, the electrode rod assembly 1 includes 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. In addition, both ends of the first rod 10' form exposed base material surfaces on which no metal nitride film is formed. The base material 12' and the metal nitride film 14' may be made of the same material as the electrode rod 10 described with reference to FIG. 2.

[0084] Meanwhile, a second rod 20 is connected to the front end of the first rod 10'. The first rod 10' and the second rod 20 may be connected by a joint S. The joint S may be provided by soldering or brazing an Au-Ni alloy joint material or an alloy joint material containing Ti at an appropriate temperature.

[0085] In the present invention, the second rod 20 may include a second base material 22 and a second metal nitride film 24 covering the second base material. In addition, it is preferable that the second base material 22 at both ends of the second rod 20 is exposed.

[0086] In the present invention, the second base material 22 and the second metal nitride film 24 may be made of the same material as the first base material 12' and the first metal nitride film 14'.

[0087] Alternatively, the second base material 22 may include a metal of a different material from that of the first base material 12'. In this case, the second base material 22 may use a metal or alloy having a similar thermal expansion coefficient to that of the electrode pad. For example, when Mo, W or an alloy thereof is used for the electrode pad, an alloy having a low thermal expansion coefficient such as Kovar may be used for the second base material 22. In this case, when a nickel-based alloy such as Kovar is used for the second base material 22, the second metal nitride film 24 of FIG. 3 may not be provided.

[0088] 3, the second rod 20 of the assembly 1 may be electrically connected to an electrode pad, and the first rod 10' of the assembly 1 may be electrically connected to an external power source. Of course, the reverse connection method is also possible.

[0089] Although the case where two electrode rods are connected in series to form an electrode rod assembly has been described above with reference to Fig. 3, the present invention is not limited thereto, and for example, an electrode rod assembly formed of three or more electrode rods is also possible. Some or all of the electrode rods forming these electrode rod assemblies may have the electrode rod structure described in relation to Fig. 2.

[0090] FIG. 4 is a cross-sectional view that diagrammatically shows a part of a susceptor according to an embodiment of the present invention.

[0091] 4, a (ceramic) susceptor 100 includes a ceramic plate 110, an electrode 111 embedded in the ceramic plate 110, and an electrode pad 112 for electrical connection of the electrode. The ceramic plate 110 has an opening 190 for exposing the electrode pad, and an electrode rod 10 is coupled to the opening. The electrode rod 10 supplies power (e.g., RF (Radio Frequency) power) to the electrode 111.

[0092] Meanwhile, a support eyelet 120 for supporting the electrode rod 10 within the opening may be further provided on the outer periphery of the electrode rod 10. The support eyelet 120 may be screwed into the opening. To this end, a thread 191 may be formed on a part of the inner periphery of the opening 190, and correspondingly, a coupling structure (e.g., male thread) for fastening with the thread 191 (e.g., female thread) may be provided on the outer side of the support eyelet 120.

[0093] Meanwhile, although not shown, in the present invention, 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, in addition to the electrode 111. Therefore, although the structure of the electrode rod 10 of the electrode 111 will be described in this specification, this structure may also be applied to an electrode rod for connecting the heating element (not shown) to the electrode rod.

[0094] In the present invention, the ceramic plate 110 may be configured such that electrodes 111 and / or heating elements (not shown) are disposed (embedded) at a predetermined interval between ceramic materials. The ceramic plate 110 may be configured to stably hold a substrate to be processed and to perform heating using a heating element (not shown) and / or a plasma enhanced chemical vapor deposition process using the electrodes 111. The ceramic plate 110 may be formed as a plate-like structure having a predetermined shape. As an example, the ceramic plate 110 may be formed as a circular plate-like structure, but is not limited thereto. Here, the ceramic material may be at least one of Al2O3, Y2O3, Al2O3 / Y2O3, ZrO2, AlC (autoclaved lightweight concrete), TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, BxCy, BN, SiO2, SiC, YAG, mullite, and AlF3, and is preferably aluminum nitride (AlN).

[0095] 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 and the electrode pad 112 are electrically connected by joining such as soldering or brazing.

[0096] In the present invention, the electrodes 111, the electrode pads 112, the support eyelets 120 and the heating element (not shown) may be formed of a conductive material such as tungsten (W), molybdenum (Mo), silver (Ag), copper (Cu), nickel (Ni), gold (Au), platinum (Pt), niobium (Nb), titanium (Ti) or an alloy thereof.

[0097] In the present invention, the electrode rod 10 has low resistance, i.e., low impedance, and is embodied as a paramagnetic material. Since the base material of the electrode rod 10 is made of Mo, W, or an alloy thereof, which is a paramagnetic material, the electrode rod 10 has a larger skin depth than Ni or a Ni alloy, and as a result, exhibits improved impedance characteristics.

[0098] On the other hand, the base materials of the electrode rods, molybdenum, tungsten and their alloys, show a tendency to react with oxygen and oxidize more easily than Ni or Ni alloys, and therefore, when the base materials are heated by application of RF current, the electrode rods are oxidized and deteriorated.

[0099] In order to solve such problems, the present invention provides a metal nitride film on the surface of the base material of the electrode rod 10. In addition, in the present invention, a metal nitride film is formed on the outer circumferential surface of the electrode rod, but a metal nitride film is not formed on the end where the electrode rod connects to other components. This allows the electrode rod to provide good electrical connection with adjacent components while complementing the oxidation resistance of the base material.

[0100] In the present invention, the electrode rod has controlled electrical characteristics. In the present invention, the resistivity and the ratio of the metal nitride film and the metal base material may be controlled to be within an appropriate range.

[0101] In addition, in the present invention, the metal nitride film may be appropriately designed according to the frequency and power of the RF current drawn into the electrode rod. When the RF power frequency increases, the skin depth of the workpiece decreases and the amount of heat generated on the workpiece surface may increase. In this case, it is preferable to increase the thickness of the metal nitride film.

[0102] For example, when the RF power frequency introduced into the electrode rod is 10 MHz, the skin depth of the Mo base material is about 38 μm, and when the RF power frequency is 100 MHz, the skin depth of the Mo base material is 12 μm.

[0103] In the present invention, in an environment where an RF power frequency of 10 to 40 MHz is used (for example, 13.56 MHz, 27.12 MHz, etc.), the thickness of the metal nitride film is preferably in the range of 4 to 10 μm.

[0104] In the present invention, one end of the electrode rod 10 may be joined to the electrode pad 112 by soldering or brazing. To this end, a first conductive filler 151 for joining to the electrode pad 112 may be provided on one end of the electrode rod 10.

[0105] In addition, a second conductive filler 152 may be provided around the electrode rod 10 inserted inside the support eyelet 120 to fill the space between the support eyelet 120 and the electrode rod 10. The first and second conductive fillers 151 and 152 may be provided by soldering or brazing an Au-Ni alloy bonding material or an alloy bonding material containing Ti at an appropriate temperature.

[0106] In the present invention, the amounts of the first and second conductive fillers may be appropriately controlled.

[0107] FIG. 5 is a cross-sectional view that illustrates a schematic structure of a susceptor according to another embodiment of the present invention.

[0108] 5, the susceptor has substantially the same structure as that of FIG. 3, except that the electrode rod 10 of FIG. 3 is replaced with the electrode rod assembly 10 described in relation to FIG. 2. The electrode rod assembly 1 includes a first rod 10' and a second rod 20 that are brazed and joined by the brazing joint 162 described in relation to FIG. 2, and the description of each component has been described in relation to FIG. 2, so that the description thereof will be omitted. Meanwhile, as described above, the second rod 20 does not need to be provided with the metal nitride film 24.

[0109] 6 is a flow chart showing a process for forming a metal nitride film on an electrode rod of a susceptor according to an embodiment of the present invention. In this embodiment, an AlCrN film is formed as the metal nitride film.

[0110] Referring to FIG. 6, in the present invention, various deposition techniques, for example, a PVD (Physical Vapor Deposition) technique such as arc ion plating, may be applied to the AlCrN formation process.

[0111] As shown in the figure, the coating of the electrode rod 10 may be formed by including a plasma pretreatment step (S110), an adhesion layer formation step (S120), and a reactive vapor deposition step (S130).

[0112] First, the surface of a base material made of Mo, W or an alloy thereof is plasma pretreated (S110). In the plasma pretreatment step (S110), the base material 12 of an electrode rod is inserted into an arc ion plating device or a sputtering device, and a 1×10 -5 Torr (133.3 × 10 -5 The surface of the base material 12 of the electrode rod is cleaned by plasma pretreatment at a vacuum level of 1000 MPa or less (1000 Pa). This is to ensure that the adhesion layer and metal nitride film are optimally coated in the subsequent process.

[0113] Next, the adhesion layer forming step (S120) is for reducing the internal stress of the metal nitride film to be formed and for improving adhesion. The adhesion layer may include a metal such as Cr or an alloy thereof. Preferably, the adhesion layer may include a Cr nitride or a nitride of a Cr alloy.

[0114] In the present invention, the adhesive layer may be formed by an arc ion plating or sputtering method. For example, a CrN layer may be deposited as an adhesive layer on the surface of the base material 12 of each electrode rod in an arc ion plating or sputtering device to a thickness of 0.1 to 4.0 μm. In this case, a Cr target may be placed in the arc ion plating or sputtering device in advance, and the CrN layer may be formed on the surface of the base material 12 of the electrode rod at a predetermined vacuum level by a PVD method while injecting nitrogen into the reactor.

[0115] In the reactive deposition process (S130), Al and Cr targets or Al-Cr alloy targets are loaded into the arc ion plating equipment, and 1×10 -2 Torr (133.3 × 10 -2 The AlCrN is formed to a thickness of 1.0 to 10.0 μm at a vacuum of about 1000 MPa (1000 MPa, 1 Pa). In the case of an AlCr alloy target, the target may be an AlCr alloy target containing aluminum (Al) and chromium (Cr) at a predetermined ratio (e.g., 7:3 at%). In contrast, when an Al target and a Cr target are used, the Al / Cr ratio can be adjusted by changing the current of each target.

[0116] As described above, the ends of the base material may be appropriately masked so that the metal nitride film is not formed on the ends of the electrode rods 10, 10'. For example, the ends of the base material may be masked by providing an adhesive tape or a photoresist film on the ends of the base material, or by using a jig. Alternatively, the exposed surface of the electrode rod may be realized by processing the ends of the electrode rod 10 on which the metal nitride film is formed to expose the base material.

[0117] <Experimental Example 1: Resistivity measurement experiment of AlCrN film> Using alloy targets with different Al and Cr contents, AlCrN films with an area of ​​30mm x 30mm and thickness of 5~7μm were formed on the surface of an Al2O3 substrate by arc ion plating. The Al and Cr ratio of the AlCrN film formed for each target was analyzed by EDS, and the resistivity of the AlCrN film was measured by the four-point wire method using Mitsubishi Chemical's Loresta-GP equipment. The resistivity of the AlCrN film was 1~15 Ω·cm.

[0118] As a result of EDS analysis of each composition, the composition ratio (at%) was as shown in Table 3 below.

[0119] [Table 3]

[0120] <Experimental Example 2: Measurement of RF power loss in electrode rod> The RF power loss was measured for Φ4×330 mm rods with different materials and coating compositions. The rods used for measurement were Ni rods, Mo rods, AlCrN / Mo rods, W rods, and AlCrN / W rods, and the composition of the AlCrN coating was the composition of #2 in Experimental Example 1.

[0121] Fig. 7 shows the results of power loss measurement. As shown in Fig. 6, in the RF (Radio Frequency) power loss rate calculated based on the impedance measurement value, it can be seen that the loss rate of Mo or AlCrN / Mo having an AlCrN film on its surface, W or AlCrN / W having an AlCrN film on its surface is reduced by about 40% compared to Ni, based on the loss rate of Ni. From these results, it can be seen that the electrode rods of Mo, W, AlCrN / Mo and AlCrN / W show superior characteristics in terms of power loss compared to Ni.

[0122] <Experimental Example 3: Oxidation resistance of electrode rod> The oxidation resistance characteristics of the material and coating composition of the electrode rod with a diameter of 2 mm and 330 mm were confirmed.

[0123] The electrode rods used were Mo, MoW, AlCrN / Mo, and AlCrN / MoW rods. The AlCrN film had the composition of #2 in Experimental Example 1.

[0124] Each rod was oxidized in a box furnace at 700℃ for 10 hours. The resistance of each rod was measured before and after the oxidation treatment. The measurements were performed using a HIOKI Resistance Meter (RM3545) under the condition of INT 10mΩ.

[0125] FIG. 8 is a graph plotting the results of measuring the resistance value before and after the oxidation treatment for each rod material.

[0126] It can be seen from Figure 8 that the resistance of each rod material increased due to the oxidation treatment. However, in the case of the rod with the AlCrN film, it can be seen that the resistance change rate before and after the heat treatment was low, and the resistance value was also low.

[0127] Meanwhile, in the present invention, the susceptor is a semiconductor device for processing various types of substrates such as semiconductor wafers, glass substrates, and flexible substrates, and includes an electrode 111 that functions as a high-frequency electrode for processing the substrates to be processed, such as dry etching using plasma or plasma-enhanced chemical vapor deposition, as described below, and the electrode 111 may also be used as a chuck electrode for use in an electrostatic chuck to support the substrates to be processed. Note that in the present invention, the susceptor may further include a heating wire (or a heating element / heating electrode) for heating the substrates to be processed to a predetermined temperature.

[0128] The electrode (or conductor) 111, such as a radio frequency electrode, an electrostatic chuck electrode, or a heating wire, may be made of a conductive metal material such as silver (Ag), platinum (Pt), palladium (Pd), gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), or titanium (Ti), or an alloy thereof. The electrode as the radio frequency electrode may be supplied with power in a semiconductor manufacturing process to perform a process such as plasma enhanced chemical vapor deposition on a substrate located on an upper surface of a susceptor. The electrode as the electrostatic chuck electrode may receive a bias from a power source in a semiconductor manufacturing process to generate an electrostatic force and chuck a substrate located on an upper surface of a susceptor, and when unloading a substrate, may be applied with an opposite bias to discharge and dechuck the substrate. The heating wire (or heating element / heating electrode) may be formed in a plate-shaped coil shape or a flat plate shape using a resistance wire having a predetermined resistance, and may be formed in a multi-layer structure for precise temperature control. The heating wire (or heating element / heating electrode) may be supplied with power and may have the function of heating a substrate placed on an upper surface of a susceptor to a certain temperature in order to perform smooth deposition and etching processes in a semiconductor manufacturing process.

[0129] Therefore, in the following description of the present invention, the electrode 111 of the ceramic susceptor will be described as functioning as a high-frequency electrode to which radio frequency (RF) power is supplied via an electrode rod; however, the present invention is not limited to this, and it should be made clear in advance that the relevant description can be similarly applied to the case in which the electrode of the ceramic susceptor in the present invention is a chuck electrode with an electrostatic chuck function, or an additional heating element is supplied with power via an electrode rod.

[0130] Hereinafter, other aspects of the present invention will be described with reference to the attached Figs. 10A to 13. In this case, in the drawings, the same components are given the same reference numerals. Furthermore, even if the components do not have the same reference numerals, as long as the components have the same names, the components may have the same structure and the same functions. In particular, the same components in the description of Figs. 2A to 8 can also be applied to Figs. 10A to 13, and detailed description of the same functions and / or configurations described above will be omitted. Furthermore, the same components in the description of Figs. 10A to 13 can also be applied to Figs. 2A to 8.

[0131] FIG. 10A is a diagram illustrating the structure of a ceramic susceptor 100 according to still another embodiment of the present invention.

[0132] 10A, a ceramic susceptor 100 according to yet another embodiment of the present invention may include a ceramic plate 110 on which an electrode 111 is disposed. Here, the ceramic plate 110 may include an electrode pad 112 connected to the electrode 111, and an electrode rod assembly 150 having one end connected to the electrode pad 112 and for supplying power to the electrode 112. In this case, the electrode rod assembly 150 includes an extension portion 130 including a first rod 131 and a second rod 132.

[0133] 10A, the electrode rod assembly 150 may include an extension 130 connected to the electrode pad 112 and a power connector 133 provided at an end of a tapered portion AA of the extension 130. That is, the electrode rod assembly 150 includes an extension 130 including a first rod 131 and a second rod 132, and includes a tapered portion AA and a power connector 133 at an end of the extension 130.

[0134] In this case, the extension 130 may include a first rod 131 and a second rod 132 brazed to the first rod 131. The second rod 132 may be made of a metal material having a thermal expansion coefficient difference of 3 or less from that of the electrode pad 112. For example, the electrode pad 112, the first rod 131, and the power connector 133 may have a thermal expansion coefficient of 4.5 to 5.6 μm / °C and may be made of Mo, W, or an alloy thereof (MoW). The second rod 132 may have a thermal expansion coefficient of 4.9 to 6.2 μm / °C and may be made of an Fe-Ni-Co alloy (for example, Kovar product) material. It is preferable that the thermal expansion coefficient of the second rod 132 differs from that of the first rod 131 including the power connector 133 by 3 or less.

[0135] 10B is a view for explaining the structure of a ceramic susceptor 200 according to still another embodiment of the present invention. In this case, one rod is connected to the electrode pad 112 and extends to the power connector 133.

[0136] 10B, a ceramic susceptor 200 according to another embodiment of the present invention may include a ceramic plate 110 on which an electrode 111 is disposed. Here, the ceramic plate 110 may include an electrode pad 112 connected to the electrode 111, and an electrode rod assembly 150 having one end connected to the electrode pad 112 for supplying power to the electrode 112.

[0137] In this case, the electrode rod assembly 150 may include a first rod or extension 131 connected to the electrode pad 112, and a power connector 133 provided at an end of a tapered portion AA of the extension 131. That is, the electrode rod assembly 150 includes the extension 131 made of one rod, and includes the tapered portion AA and the power connector 133 at the end of the extension 131. Here, for example, the extension 131 including the power connector 133 may have a thermal expansion coefficient of 4.5 to 5.6 μm / ° C. and may be made of Mo, W, or an alloy thereof.

[0138] That is, as shown in Figures 10A and 10B, the electrode rod assembly 150 of the present invention may include an extension portion 130 / 131 connected to the electrode pad 112 and a power connection portion 133 provided at the end of the tapered portion AA of the extension portion 130 / 131.

[0139] The ceramic susceptor 100 may also include a support eyelet 120 that mates with the electrode rod assembly 150. For example, the electrode rod assembly 150 may be coupled to the support eyelet 120 that is fastened to the electrode 111 by threads 191 of the ceramic plate 110.

[0140] Meanwhile, as mentioned above, although not shown, in the present invention, the ceramic plate 110 may further include a heating element (electrode) (not shown) and the electrode rod. Therefore, in the present invention, a structure related to the electrode rod assembly 150 of the electrode 111 will be described, but it is clear that such a structure may be applied to the heating element (electrode) (not shown) and the electrode rod as it is.

[0141] That is, the ceramic plate 110 may be configured such that the electrodes 111 and / or heating elements (electrodes) are disposed (embedded) at a predetermined interval between the ceramic materials. The ceramic plate 110 is configured to stably hold the substrate to be processed placed on the upper surface SS, and to perform heating using the heating elements (electrodes) and / or electrostatic chucking using the electrodes 111, semiconductor processes using plasma, etc. The ceramic plate 110 may be formed as a plate-like structure having a predetermined shape. As an example, the ceramic plate 110 may be formed as a circular plate-like structure, but is not necessarily limited thereto. Here, the ceramic material may be Al2O3, Y2O3, Al2O3 / Y2O3, ZrO2, AlC (autoclaved lightweight concrete), TiN, AlN, TiC, MgO, CaO, CeO2, TiO2, B x C yThe ceramic powder may be at least one of the following: BN, SiO2, SiC, YAG, mullite, and AlF3, and preferably aluminum nitride (AlN). Each ceramic powder may optionally contain about 0.1 to 10%, preferably about 1 to 5%, of yttrium oxide, MgO, TiO2 powder, etc.

[0142] The electrode pad 112 is embedded in the ceramic plate 110 so as to be partially exposed at the bottom surface of a predetermined aperture of the ceramic plate 110. The end surface of the electrode rod assembly 150 and the electrode pad 112 may be electrically connected by brazing.

[0143] The electrodes 111, electrode pads 112, electrode rod assemblies 150, support eyelets 120, etc. may be made of a conductive material, such as tungsten (W), molybdenum (Mo), silver (Ag), platinum (Pt), palladium (Pd), nickel (Ni), gold (Au), niobium (Nb), titanium (Ti), or alloys thereof.

[0144] In particular, in the present invention, the electrode rod assembly 150 has low impedance and is preferably a paramagnetic material. For example, the electrode rod assembly 150 may be made of a base material of Mo, W or an alloy thereof, and an oxidation-resistant coating is provided on the surface of the base material of the electrode rod assembly 150. As described above, for example, in FIG. 10A, the first rod 131 including the electrode pad 112 and the power connector 133 may be made of Mo, W or an alloy thereof, and the second rod 132 may be made of an Fe-Ni-Co alloy (e.g., Kovar product) material. Also, for example, in FIG. 10B, the extension part 131 including the power connector 133 may have a thermal expansion coefficient of 4.5 to 5.6 μm / ° C. and may be made of Mo, W or an alloy thereof.

[0145] In the present invention, the oxidation-resistant film may preferably include metal nitride films 141, 142. For example, the metal nitride film may include AlN, more preferably TiN, TiAlCrN, TiAlN, or AlCrN. This makes it possible to provide a ceramic susceptor 100 that has all the thermal, electrical (magnetic), and mechanical properties required in the manufacturing and processing environments of the ceramic susceptor 100 and is advantageous in terms of workability and material unit cost.

[0146] In the ceramic susceptor 100 of the present invention having the structure of FIG. 10A, one side of the electrode rod assembly 150 may be joined inside the support eyelet 120 and may include a first rod 131 and a second rod 132 connected by brazing. The first rod 131 and the second rod 132 may be configured as a single integrated rod as the extension part 130, or may have a structure in which the first rod 131 and the second rod 132 are joined in this manner. One end surface of the second rod 132 may be brazed to the electrode pad 112 by a first conductive filler 151, and the first rod 131 may be brazed to the other end surface of the second rod 132 by a second conductive filler 162. For example, Au-Ni metal filler or the like may be used as the conductive fillers 151 and 162. A conductive filler 152 may be provided around the rods 131 and 132 inserted inside the support eyelet 120 to fill the space between the support eyelet 120 and the rods 131 and 132 .

[0147] The electrode pad 112 may be made of Mo, W, or an alloy thereof. Since the second rod 132 is located close to the electrode 111, heat loss and thermal stress may occur. Therefore, in order to prevent heat loss and reduce cracks caused by thermal stress, it is preferable to use a metal material having a thermal expansion coefficient difference of 3 or less with the material of the electrode pad 112 as described above. In particular, in the present invention, metal nitride films 141 and 142 may be included on the surface of the electrode rod assembly 150 to prevent oxidation (corrosion), i.e., the metal nitride film 141 on the surface of the second rod 132 and the metal nitride film 142 on the surface of the first rod 131. In some cases, the metal nitride film 141 may not be necessary on the surface of the second rod 132, but the metal nitride film 141 may be formed on the surface of the second rod 132 if necessary.

[0148] In addition, the electrode rod assembly 150 includes a power connection portion 133 that is tapered and extends to the end of the extension portion 130 and has a different diameter than the extension portions 131, 132 (130).

[0149] For each brazing joint as described above, first, the first conductive filler 151 is injected in advance around the bottom surface of the opening 190, i.e., the exposed portion of the electrode pad 112, and the second rod 132 is pressed inside the support eyelet 120 to bring one end surface of the second rod 132 into close contact with the electrode pad 112. Next, the second conductive filler 162 is sufficiently injected onto the upper portion of the other end surface of the second rod 132, and one end surface of the first rod 131 is brought into close contact with the injected second conductive filler 162, heated at a high temperature, and then cooled.

[0150] 10B, one end surface of the first rod or extension 131 consisting of a single first rod 131 may be brazed to the electrode pad 112 by the first conductive filler 151 in a manner similar to the above method, except that the second rod 132 is omitted. A conductive filler 152 may be provided around the rod 131 inserted inside the support eyelet 120 to fill the space between the support eyelet 120 and the rod 131.

[0151] By using such ceramic susceptor 100 / 200 of the present invention, the power connector 133 of the electrode rod assembly 150 is connected to a power source and power is supplied to the electrode 111 via the electrode pad 112, thereby performing semiconductor processes such as dry etching using plasma and plasma enhanced chemical vapor deposition, or functioning as an electrostatic chuck, and the heat (or high frequency) generated from the heating element (electrode) can be used to heat a substrate to be processed (e.g., a semiconductor wafer, a glass substrate, a flexible substrate, etc.) in a semiconductor process, etc.

[0152] In particular, the electrode rod assembly 150 may be made of Mo, W or an alloy (e.g., MoW, MoNi, WNi, etc.) containing at least one of them at a weight ratio (wt%) greater than other metal materials, and by including metal nitride films 141, 142 on the surface of the electrode rod assembly 150 in preparation for oxidation (corrosion), oxidation of the electrode rod assembly 150 can be effectively prevented and a factor of impedance increase with use can be eliminated. By reducing such changes such as impedance increase of the electrode rod assembly 150 and eliminating energy loss converted to heat energy in the electrode rod assembly 150, electrical energy can be efficiently consumed in plasma discharge. In addition, by reducing the heat generated from the electrode rod assembly 150, a hot-spot zone is not formed on the upper surface of the ceramic plate 110 that holds the substrate, and therefore the uniformity of the thickness and film quality of the thin film deposited on the substrate can be improved, thereby increasing the yield. In addition, the temperature rise of the ceramic portion in contact with the portion where the electrode rod assembly 150 is fastened is eliminated, thereby reducing the destruction of the ceramic susceptor 100 due to thermal shock and reducing the occurrence of arcs at the brazing joint. Therefore, the reduction in impedance change of the electrode rod assembly 150 in the present invention provides a ceramic susceptor 100 with improved durability, which can contribute to an increase in the yield of semiconductor devices.

[0153] FIG. 11 is an enlarged view of peripheral portion 200 including tapered portion AA between extension portion 130 / 131 and power connection portion 133 of the present invention of FIGS. 10A and 10B.

[0154] 11, as described above, the power connection part 133 is provided at the end of the tapered portion AA of the extension part 130 / 131 of the electrode rod assembly 150. That is, the tapered portion AA may be formed by tapering using a machine tool so that the tapered portion AA is included between the extension part 130 / 131 and the power connection part 133, which have different diameters. The machine tool may include a processing device using various methods such as a milling machine, a lathe, a Machining Center (MCT), a Computer Numerical Control (CNC), a laser, etc.

[0155] In the present invention, the tapered portion AA of the electrode rod assembly 150 may be formed by processing the cylindrical rod 130 / 131 at the same inclination angle θ along the circumference thereof. The electrode rod assembly 150 may have a total length of, for example, 250 to 400 mm, of which the length LL of the tapered end AA, which gradually narrows from the extension portion 130 / 131 toward the power connection portion 133, is preferably 1.0 mm to 10.0 mm in the longitudinal direction of the extension portion 130 / 131.

[0156] The inclination angle θ of the tapered portion AA of the extension portion 130 / 131 may be 10° to 80° with respect to the longitudinal direction of the extension portion 130, and for a smoother, more streamlined connection, may 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 may be 12° to 16°. This allows the longitudinal cross section of the tapered portion AA of the extension portion 130 / 131 to be trapezoidal.

[0157] In addition, the position of the end of the tapered portion AA of the extension portion 130 / 131 with a smaller diameter may be determined to a predetermined position for improving oxidation resistance and corrosion resistance. The position of the end of the tapered portion AA of the extension portion 130 / 131 with a smaller diameter may be, for example, a position that is 10% or more lower, preferably 20% or more lower, than the temperature of the ceramic plate 110, i.e., the temperature of the bottom end surface (see BB in FIG. 12) of the ceramic plate 110 (e.g., 650° C., 550° C., 450° C., etc.) when the ceramic plate 110 is started, i.e., when the heating element (electrode) is activated (or, if there is no heating element, an external heater can be used).

[0158] In the embodiment described below, the total length of the electrode rod assembly 150 is about 330 mm, the diameter of the extensions 131 and 132 is 4.6 mm, the diameter of the power connection part 133 is 4 mm, the length LL of the tapered end AA is 2.5 mm, and the inclination angle θ is 13.7°. In this case, it was confirmed that the position where the temperature of the lowest end surface of the ceramic plate 110 (see BB in FIG. 12) is 80% or less (e.g., 650°C, 550°C, 450°C, etc.) is 5 mm or more away from the lowest end surface of the ceramic plate 110 (see BB in FIG. 12).

[0159] That is, the tapered portion AA is placed at a position away from the ceramic plate 110 where the temperature drops significantly during the semiconductor process, thereby making it possible to prevent oxidation or corrosion due to high temperatures that may occur in that portion during use in the brazing bonding or deposition process.

[0160] FIG. 12 shows an embodiment in which the ceramic susceptor 100 of the present invention is installed in a process chamber 300 of a semiconductor equipment.

[0161] Referring to FIG. 12, a ceramic susceptor 100 / 200 may be installed inside a process chamber 300 of a semiconductor equipment for performing a semiconductor process such as plasma enhanced chemical vapor deposition, and the ceramic susceptor 100 / 200 may be installed so as to be supported by a shaft 310 having a through hole therein and a predetermined connecting mount 320.

[0162] In the ceramic susceptor 100 / 200, the electrode rod 130 / 132 connected to the electrode pad 112 of the ceramic plate 110 may extend through the inside of the shaft 310 and through the connection mount 320 to the outside of the chamber 300. That is, the power connection part 133 of the electrode rod 130 / 132 extends to the outside of the chamber 300, and the periphery of the end PP of the power connection part 133 is connected to a connecting means of the power source, so that the necessary power supply can be received.

[0163] In the chamber 300, the above-mentioned heating elements of the ceramic plate 110 were operated so that the temperatures of the ceramic plate 110 reached 650°C, 550°C, and 450°C, respectively, and the temperatures were measured at positions A, B, C, D, E, and F while descending from an outer position A of the shaft 310 aligned with the bottom end surface BB at a predetermined interval downward. As a result, it was confirmed that the temperature showed a linear decrease as shown in Table 4 below. The susceptor sample used here had an electrode rod assembly 150 with a total length of about 330 mm, extension parts 131 and 132 with a diameter of 4.6 mm, and a power connection part 133 with a diameter of 4 mm. In addition, the length LL of the tapered end AA was 2.5 mm, and the inclination angle θ was 13.7°.

[0164] [Table 4]

[0165] As can be seen in the table above, when the temperature at position A on the bottom surface BB of the ceramic plate 110 is 650°C, 550°C, and 450°C, respectively, all positions that are 10% or more lower than that temperature are position C, and all positions that are 20% or more lower than that temperature are position D.

[0166] Therefore, in the above case, the position of the smaller diameter end of the tapered portion AA of the extension portion 130 / 131 may be located at position C, D, E, or F, and preferably at positions D, E, or F.

[0167] This allows the tapered portion AA to be disposed at a position whose temperature is 10% or more lower than the temperature of the ceramic plate 110, thereby improving the oxidation resistance and corrosion resistance of the electrode rod assembly 150.

[0168] In this manner, the ceramic susceptor 100 according to the present invention positions the tapered portion AA at a position where the electrode rod assembly 150 is separated from the ceramic plate 110 in order to receive power, particularly at a position where the temperature drops significantly during semiconductor processing, and the shape of the tapered portion AA is designed to be streamlined, such as a trapezoid, so as not to form a steeply inclined edge, thereby improving durability and ensuring a long life so as to have good high frequency transmission characteristics for a long period of time even in oxidation-resistant and corrosion-resistant environments.

[0169] FIG. 13 is a flow chart illustrating a process for forming a film on the electrode rod assembly 150 of the ceramic susceptor 100 according to an embodiment of the present invention.

[0170] 13, first, a physical vapor deposition (PVD) method such as arc ion plating may be applied to form metal nitride films 141, 142 on the surface of the base material of the electrode rod assembly 150 made of Mo, W, or an alloy thereof to form a coating on the electrode rod assembly 150. As shown in the figure, the coating on the electrode rod assembly 150 may be formed by including a plasma pretreatment process (S110), a process of forming an adhesive layer 145 (S120), and a reactive deposition process (S130).

[0171] First, in the plasma pretreatment process (S110), the base material of the electrode rod assembly 150 is inserted into an arc ion plating device or a sputtering device before the adhesive layer 145 is formed. -5 The base material surface of the electrode rod assembly 150 is cleaned by plasma pretreatment at a vacuum level of Torr or less in order to optimally coat the adhesion layer 145 and the metal nitride films 141 and 142 in the subsequent process. Here, the electrode rod assembly 150 may be a rod on which the extensions 130 / 131, the tapered portion AA, and the power connection portion 133 are formed in advance.

[0172] Next, the adhesion layer formation step (S120) is a step for reducing the internal stress of the metal nitride films 141, 142 and for good adhesion. The adhesion layer 145 may include a metal such as Cr or an alloy thereof. Preferably, the adhesion layer may include a Cr nitride or a nitride of a Cr alloy.

[0173] In the present invention, the adhesive layer 145 may be formed by an arc ion plating or sputtering method. For example, a CrN layer may be deposited to a thickness of 0.1 to 4.0 μm on the base metal surface of the extension part 130 / 131 of each electrode rod assembly 150 using an arc ion plating or sputtering device as the adhesive layer 145. In this case, a Cr target is previously loaded into the arc ion plating or sputtering device, and while nitrogen is injected into the reactor, the CrN layer can be formed on the base metal surface of the extension part 130 / 131 of the electrode rod assembly 150, i.e., the extension part 130 / 131 including the tapered portion AA and the power connection part 133 of the electrode rod assembly 150, at a predetermined vacuum level using a PVD method.

[0174] In the reactive deposition process (S130), an Al target and a Cr target are first loaded into the arc ion plating or sputtering equipment, or an AlCr alloy target is loaded, and nitrogen is injected into the reactor of the arc ion plating or sputtering equipment while PVD is performed to deposit 1×10 -2 The metal nitride films 141, 142 are formed to a thickness of 1.0 to 10.0 μm at a vacuum of about Torr. The AlCr alloy target may be an AlCr alloy target in which aluminum (Al) and chromium (Cr) are alloyed at a predetermined ratio (e.g., 7:3 at%). Alternatively, when an Al target and a Cr target are charged and used, the ratio of Al and Cr required for forming the metal nitride films 141, 142 can be adjusted by changing the current for each target.

[0175] As described above, in the ceramic susceptor 100 / 200 according to the present invention, the tapered portion AA is located at a position where the electrode rod assembly 150 is separated from the ceramic plate 110 to receive power, particularly at a position where the temperature drops significantly during semiconductor processing, and the shape is designed to be streamlined, such as a trapezoid, so as not to form a steeply inclined edge, thereby improving durability and ensuring a long life so as to have good high frequency transmission characteristics for a long period of time even in oxidation-resistant and corrosion-resistant environments.

[0176] As described above, the present invention has been described by specific matters such as specific components, limited embodiments, and drawings, but these are provided only to assist in a more general understanding of the present invention, and the present invention is not limited to the above embodiments, and various modifications and variations may be made by those having ordinary knowledge in the 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 limited to the described embodiments, and not only the scope of the claims described below, but also technical ideas that are equivalent or have equivalent modifications to the scope of the claims should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0177] 1,150 Electrode Rod Assembly 10,10' electrode rod 12,12', 22 Base material 14, 14', 24, 141, 142 Metal nitride film 100 Susceptor 110 Ceramic Plate 111 Electrode 112 Electrode Pads 120 Support eyelet

Claims

1. A susceptor including a ceramic plate on which a radio frequency electrode is disposed, an electrode rod having one end electrically connected to the high frequency electrode and the other end electrically connected to a power source for supplying power to the high frequency electrode; The electrode rod is A base material of Mo, W or an alloy of these metals; a metal nitride film covering a surface of the base material; A susceptor, wherein one end of the electrode rod includes an exposed base material surface that is not covered with a metal nitride film.

2. The susceptor of claim 1 , wherein the metal nitride film comprises an AlCrN film.

3. The susceptor of claim 2, wherein the Cr / (Al+Cr) atomic ratio of the AlCrN film is 0.1 to 0.

9.

4. The susceptor according to claim 1 , wherein the metal nitride film comprises at least one nitride film selected from the group consisting of AlCrSiN, AlCrSiWN, and AlTiCrN.

5. The ratio of the resistivity of the metal nitride film to the resistivity of the base material is 10 ２ The susceptor according to claim 1 .

6. The ratio of the resistivity of the metal nitride film to the resistivity of the base material is 10 ３ The susceptor according to claim 1 .

7. The ratio of the resistivity of the metal nitride film to the resistivity of the base material is 10 ４ The susceptor according to claim 1 .

8. The susceptor of claim 1 , further comprising a CrN underlayer between the base material and the metal nitride film.

9. 2. The susceptor according to claim 1, wherein the metal nitride film has a thickness of 1.0 to 10.0 μm.

10. A susceptor including a ceramic plate on which a radio frequency electrode is disposed, an electrode rod assembly having one end electrically connected to the radio frequency electrode and another end electrically connected to a power source for supplying power to the radio frequency electrode; The electrode rod assembly includes a first electrode rod and a second electrode rod connected in series, The first electrode rod is A base material of Mo, W or an alloy of these metals; a metal nitride film covering a surface of the base material; A susceptor, wherein one end of the first electrode rod is an exposed surface of a base material that is not covered with a metal nitride film.

11. The susceptor of claim 10 , wherein the first electrode rod and the second electrode rod are joined by a joining material.

12. The susceptor according to claim 11 , wherein the joint surfaces of the first electrode rod and the second electrode rod are exposed surfaces of the base material that are not covered with a metal nitride film.

13. The susceptor of claim 10 , wherein the second electrode rod comprises a base material made of Kovar.

14. The susceptor of claim 10 , wherein the metal nitride film comprises an AlCrN film.

15. The susceptor of claim 14, wherein the AlCrN film has a Cr / (Al+Cr) atomic ratio of 0.1 to 0.

9.

16. The susceptor according to claim 10, wherein the metal nitride film comprises at least one nitride film selected from the group consisting of AlCrSiN, AlCrSiWN, and AlTiCrN.

17. The ratio of the resistivity of the metal nitride film to the resistivity of the base material is 10 ２ The susceptor according to claim 10 .

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