Ceramic susceptor and method for manufacturing the same

Abstract

To provide a method for manufacturing a ceramic susceptor, capable of improving bonding force between the upper and lower plates of a MMC (a Metal Matric Composite) metal ceramic composite base body, and the ceramic susceptor.SOLUTION: A ceramic susceptor base body includes a body obtained by bonding lower and upper plates 210 and 220 consisting of a metal ceramic composite, respectively. A method for manufacturing the aceramic susceptor base body comprises steps of: successively laminating a first active metal layer 321, a first aluminum layer 322 and a blazing filler layer 323 on the bonded surface of the upper plate; successively laminating a second active metal layer 311 and a second aluminum layer 312 on the bonded surface of the lower plate; and brazing and bonding the lower and upper plates by the brazing filler layer.SELECTED DRAWING: Figure 2C

Description

[Technical field]

[0001] The present invention relates to a ceramic susceptor, and more particularly to a brazing method for improving the bonding strength between upper and lower plates of a metal-matric composite (MMC) base body. [Background technology]

[0002] 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. These thin film layers are sequentially deposited on the substrate by a chemical vapor deposition (CVD) process or a physical vapor deposition (PVD) process. The CVD process includes a low pressure chemical vapor deposition (LPCVD) process, a plasma enhanced chemical vapor deposition (PECVD) process, a metal organic chemical vapor deposition (MOCVD) process, and the like.

[0003] In such CVD and PVD equipment, a ceramic susceptor is disposed to hold a glass substrate, a flexible substrate, a semiconductor wafer substrate, etc. and to process a semiconductor. The ceramic susceptor is installed in the CVD and PVD equipment and may include a chuck electrode for holding a substrate and a heating wire for heating the substrate in a heat treatment process, etc. Also, the ceramic susceptor may include a radio frequency (RF) electrode instead of a heating wire, or may further include a radio frequency (RF) electrode and be used to generate plasma in an etching process of a thin film layer formed on a substrate, etc.

[0004] 1A and 1B are diagrams for explaining the problems of conventional ceramic susceptors. Fig. 1A shows the upper and lower plates joined by a brazing filler of an Al-based base body, and Fig. 1B shows the upper and lower plates joined by a brazing filler of an MMC (Metal Matric Composite) metal ceramic composite base body.

[0005] As shown in Figure 1A, the upper and lower plates of the aluminum-based base body of a conventional ceramic susceptor can be joined by a general aluminum brazing method. At this time, the base body and the brazing filler are made of the same material, so the brazing joint can be performed well.

[0006] Currently, due to extreme process environment changes, especially to compensate for low-temperature deformation, MMC (Metal Matrix Composite) material, which is a composite of Al and ceramic powder, i.e., metal ceramic composite, is applied to the base body of ceramic susceptor. However, as shown in Figure 1B, in the MMC metal ceramic composite base body of the conventional ceramic susceptor, when the upper and lower plates are joined by the general aluminum brazing joining method, the brazing filler material between the metal ceramic composite materials is a different material type, so there are problems such as leakage of process gas such as He gas during the process in the semiconductor equipment, leakage of cooling water in the cooling channel, and vacuum failure, which are the cause of the process itself failure or the decrease in yield. Summary of the Invention [Problem to be solved by the invention]

[0007] Therefore, the present invention has been devised to solve the above-mentioned problems, and an object of the present invention is to provide a method for manufacturing a base body of a ceramic susceptor, in which a multi-layer (active metal layer and aluminum layer) surface treatment is applied between a base body plate and a brazing filler in order to improve the bonding strength between the upper and lower plates of an MMC (Metal Matric Composite) metal ceramic composite base body, and a ceramic susceptor using the base body. [Means for solving the problem]

[0008] First, to summarize the features of the present invention, in one aspect of the present invention for achieving the above-mentioned object, a manufacturing method for a base body of a ceramic susceptor includes a base body including a joint of a lower plate and an upper plate, each made of a metal ceramic composite, and includes the steps of sequentially laminating a first active metal layer, a first aluminum layer and a brazing filler layer on the joint surface of the upper plate; sequentially laminating a second active metal layer and a second aluminum layer on the joint surface of the lower plate; and brazing the lower plate and the upper plate so that the first aluminum layer and the second aluminum layer are joined via the brazing filler layer.

[0009] A groove is included between the joining surfaces of the lower plates.

[0010] The first active metal layer and the second active metal layer may include at least one of Ti, Zr, Nb, Hf, and Ta.

[0011] The first active metal layer and the second active metal layer may have a thickness of 1 to 5 μm.

[0012] The first aluminum layer and the second aluminum layer may have a thickness of 5 to 10 μm.

[0013] According to another aspect of the present invention, there is provided a ceramic susceptor including a base body and an insulating plate, the base body including a lower plate and an upper plate each made of a metal ceramic composite material, and a joint therebetween, the joint including a first active metal layer, a first aluminum layer and a brazing filler layer stacked in sequence on the upper plate; and a second active metal layer and a second aluminum layer stacked in sequence on the lower plate, the lower plate and the upper plate being brazed together by the brazing filler layer. Effect of the Invention

[0014] According to the ceramic susceptor and its manufacturing method of the present invention, the bonding strength between the upper and lower plates of the MMC metal ceramic composite base body can be improved by applying a multi-layer (active metal layer and aluminum layer) surface treatment between each plate of the upper and lower plates of the base body and the brazing filler, thereby reducing the leak rate of He gas during the process in the semiconductor equipment, improving the degree of vacuum, and reducing the leakage of the coolant in the cooling passage, thereby maintaining a stable process and contributing to improving the yield. In the embodiment, it was confirmed that the leak rate of the He gas was reduced from the previous 1.0E-03 (mbar*l / s) to 2.0.E-08 (mbar*l / s) after the improvement. [Brief description of the drawings]

[0015] 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.

[0016] [Figure 1A] 1A and 1B are diagrams for explaining problems with a conventional ceramic susceptor. [Figure 1B] 1A and 1B are diagrams for explaining problems with a conventional ceramic susceptor. [Figure 2A-2C] 4A to 4C are cross-sectional views of a lower plate and an upper plate of a base body for explaining a method for manufacturing a ceramic susceptor according to an embodiment of the present invention. [Diagram 3] 5A to 5C are diagrams illustrating a bonding structure of an insulating plate to a base body of a ceramic susceptor according to an embodiment of the present invention. [Figure 4] 1 is a photograph of an example of an actually manufactured lower plate of a base body of a ceramic susceptor according to an embodiment of the present invention. [Diagram 5] 1 is a photograph showing an example of an upper plate of an actually manufactured base body of a ceramic susceptor according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] 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.

[0018] 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.

[0019] 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.

[0020] First, in the present invention, the ceramic susceptor is a semiconductor device for processing substrates for various purposes such as semiconductor wafers, glass substrates, flexible substrates, etc., and may be provided with an electrostatic chuck electrode for use as an electrostatic chuck to hold the substrate, or may be provided with a heating wire (or heating element) to heat the substrate to a predetermined temperature, or may further be provided with a high-frequency electrode or may be provided instead of a heating wire for processing the substrate to be processed, such as plasma-enhanced chemical vapor deposition.

[0021] Therefore, the conductor (or electrode) referred to below will be described as the heating wire (or heating element), but it should be made clear in advance that this is not limited to this and can also be applied directly to the high-frequency electrode and the electrostatic chuck electrode.

[0022] For example, the heating wire (or heating element) serving as the conductor (or electrode) may be formed in the form of a plate-like coil or a flat plate using a resistive wire having a predetermined resistance. The heating wire (or heating element) may also be formed in a multi-layer structure for precise temperature control. The heating wire (or heating element) may receive power and have the function of heating a substrate positioned on an upper surface of a ceramic susceptor to a constant temperature in order to perform deposition and etching processes smoothly in a semiconductor manufacturing process.

[0023] Also, for example, the electrostatic chuck electrode or the radio frequency electrode as the conductor (or electrode) may be made of a conductive metal material such as silver (Ag), gold (Au), nickel (Ni), tungsten (W), molybdenum (Mo), titanium (Ti), etc., or an alloy thereof. The electrostatic chuck electrode can chuck a substrate positioned on the upper surface of a ceramic susceptor by applying a bias of a power source to the electrode during a semiconductor manufacturing process to generate an electrostatic force, and when the substrate is unloaded, an opposite bias is applied to the electrode to discharge the electrostatic force and dechuck the substrate. The radio frequency electrode can be supplied with power during a semiconductor manufacturing process to perform a process such as plasma enhanced chemical vapor deposition on a substrate positioned on the upper surface of a ceramic susceptor.

[0024] Such a ceramic susceptor 1000 of the present invention includes a base body (1100 in FIG. 3) including a lower plate (210 in FIG. 3) and an upper plate (220 in FIG. 3) bonded thereto, and an insulating plate (1200 in FIG. 3) bonded thereon, and the above-mentioned conductors (or electrodes) 1210, 1220 are disposed / embedded within the insulating plate (1200 in FIG. 3).

[0025] Hereinafter, a method for manufacturing a ceramic susceptor 1000 according to one embodiment of the present invention and the structure of the ceramic susceptor 1000 manufactured thereby will be described in detail with reference to FIGS. 2A to 2C and 3 to 5. FIG.

[0026] 2A to 2C are cross-sectional views of a lower plate and an upper plate of a base body for explaining a method for manufacturing a ceramic susceptor according to one embodiment of the present invention.

[0027] First, referring to FIG. 2A, to manufacture a ceramic susceptor 1000 according to one embodiment of the present invention, a first active metal layer 321, a first aluminum layer 322 and a brazing filler layer 323 are sequentially laminated on the bonding surface of the upper plate 220, i.e., one side surface of the upper plate 220.

[0028] Also, referring to FIG. 2B, a second active metal layer 311 and a second aluminum layer 312 are sequentially laminated on the bonding surface of the lower plate 210, i.e., on the substrate between the groove portion 211 (see FIG. 4) which becomes the cooling flow path (215 in FIG. 3) of the lower plate 210.

[0029] Also, referring to FIG. 2C, the lower plate 210 and the upper plate 220 are brazed together using the brazing filler layer 323, thereby manufacturing the base body 1100 of the ceramic susceptor 1000 of the present invention, which is made up of the lower plate 210 and the upper plate 220.

[0030] For the brazing bonding, the lower plate 210 and the upper plate 220 are bonded to each other, and then heated at a high temperature and cooled, so that the conductive filler of the brazing filler layer 323 can bond the lower plate 210 and the upper plate 220. For example, Au-Ni metal filler, Al-based metal filler, etc. may be used as the conductive filler of the brazing filler layer 323. One side of the upper plate 220 is bonded to the lower plate 210, and as shown in Fig. 5, the other side of the upper plate 220 is provided with a hole 225 corresponding to the hole of the insulating plate (1200 in Fig. 3), and the hole 225 is connected to a flow path for supplying a cooling gas, etc., and may be configured to supply the cooling gas onto the insulating plate (1200 in Fig. 3) as necessary.

[0031] In the above, the lower plate 210 and the upper plate 220 may be made of a metal ceramic composite material, i.e., an MMC (Metal Matric Composite) material of Al-ceramic composite powder, in order to prevent deformation due to extreme process environment changes, especially in response to low-temperature deformation, and may be manufactured using powder in which Al is composited with SiC, Si, B (Boron), Al2O3 (alumina), graphite, etc.

[0032] In addition, the first active metal layer 321 of the upper plate 220 and the second active metal layer 311 of the lower plate 210 may include any one of Ti, Zr, Nb, Hf, and Ta, or an alloy thereof, and may be formed to a thickness of 1 to 5 μm.

[0033] Furthermore, the first aluminum layer 322 of the upper plate 220 and the second aluminum layer 312 of the lower plate 210 may be formed to a thickness of 5 to 10 μm.

[0034] The first active metal layer 321 of the upper plate 220 and the second active metal layer 311 of the lower plate 210 may function to improve the bonding strength by being melted together with the conductive filler and the first and second aluminum layers 322 and 312 during the brazing bonding. An interface product may be formed by an oxidation-reduction reaction to improve the bonding strength on both sides at an interface having different physical and chemical properties (see "Bonding of Ceramic and Metal Using Active Metal Brazing", Journal of the Microelectronics & Packaging Society, Vol. 18, No. 3, p. 1-7. 2011).

[0035] When the base body 1100 is obtained by the above-described method for manufacturing the ceramic susceptor 1000 according to an embodiment of the present invention, the base body 1100 may be bonded to the insulating plate 1200 to manufacture the ceramic susceptor 1000 according to an embodiment of the present invention.

[0036] FIG. 3 is a diagram for explaining a joining structure between a base body 1100 and an insulating plate 1200 of a ceramic susceptor 1000 according to an embodiment of the present invention.

[0037] Referring to FIG. 3, a ceramic susceptor 1000 according to an embodiment of the present invention includes a base body 1100 including a lower plate 210 and an upper plate 220 bonded thereto, and an insulating plate 1200 bonded thereon.

[0038] Conductors (or electrodes) 1210, 1220 are disposed / embedded in the insulating plate 1200. As described above, the ceramic susceptor 1000 is a semiconductor device for processing various types of substrates to be processed, such as semiconductor wafers, glass substrates, and flexible substrates, and the conductors (or electrodes) 1210, 1220 may be an electrostatic chuck electrode used as an electrostatic chuck to hold the substrate to be processed, a heating wire (or heating element) for heating the substrate to a predetermined temperature, or a high-frequency electrode for subjecting the substrate to a process such as plasma enhanced chemical vapor deposition.

[0039] The base body 1100 includes a cooling channel 215 formed in the groove 211 by brazing the lower plate 210 and the upper plate 220 with the brazing filler layer 323. The cooling channel 215 is a channel for circulating a coolant, such as cooling water or cooling oil, and the coolant may circulate through the cooling channel 215 to maintain the temperature of the ceramic susceptor 1000 at a constant level during a semiconductor process.

[0040] Meanwhile, joints 230, 240 between the lower plate 210 and the upper plate 220 are formed between the cooling channels 215, and the joints 230, 240 between the lower plate 210 and the upper plate 220 may include an upper plate joint 240 including a first active metal layer 321, a first aluminum layer 322, and a brazing filler layer 323 sequentially stacked on the upper plate 220, and a lower plate joint 230 including a second active metal layer 311 and a second aluminum layer 312 sequentially stacked on the lower plate 210. The lower plate 210 and the upper plate 220 are brazed and joined by the brazing filler layer 323.

[0041] <Example>

[0042] Table 1 below shows the results of manufacturing a base body 1100 with respect to the presence or absence of He gas leakage and cooling water leakage when using a lower plate 210 and an upper plate 220 made of metal ceramic composite (MMC) material and applying an Al-based metal filler to the brazing filler layer 323, depending on whether or not active metal layers 311, 321 and aluminum (Al) layers 312, 322 were applied as surface treatment conditions for the joints 230, 240 (applied: O, not applied: X).

[0043] [Table 1]

[0044] As shown in Table 1 above, when the active metal layers 311, 321 and the aluminum (Al) layers 312, 322 are not applied, and when the active metal layers 311, 321 are applied but the aluminum (Al) layers 312, 322 are not applied, defects of cooling water leakage and defects of He gas leakage at the joints with a He gas leakage standard of 1.0E-04 (mbar*l / s) or more were confirmed. In contrast, when the lower plate 210 and the upper plate 220 made of a metal ceramic composite (MMC) material are used as in the present invention, and the active metal layers 311, 321 and the aluminum (Al) layers 312, 322 are all applied as surface treatment conditions for the joints 230, 240 and brazing joints are performed, it was confirmed that the joints 230, 240 are excellent in bonding, so there is no cooling water leakage, and the He gas leakage standard is less than 1.0E-04 (mbar*l / s), improving to a slight level of gas leakage.

[0045] The following Table 2 shows a comparison of the defect rates of the manufactured base body 1100 when using a lower plate 210 and an upper plate 220 made of metal ceramic composite (MMC) material and applying an Al-based metal filler to the brazing filler layer 323, depending on whether or not active metal layers 311, 321 and aluminum (Al) layers 312, 322 were applied as surface treatment conditions for the joints 230, 240 (applied: O, not applied: X).

[0046] [Table 2]

[0047] As shown in Table 2 above, when the active metal layers 311, 321 and the aluminum (Al) layers 312, 322 were not applied, and when the active metal layers 311, 321 were applied but the aluminum (Al) layers 312, 322 were not applied, the average failure rate of cooling water leakage and He gas leakage at the joint exceeding the He gas leakage standard of 1.0E-04 (mbar*l / s) was 77%.

[0048] In contrast, when the lower plate 210 and the upper plate 220 are made of metal ceramic composite (MMC) material as in the present invention, and the active metal layers 311, 321 and the aluminum (Al) layers 312, 322 are applied as surface treatment conditions for the joints 230, 240 to perform brazing joining, the joining of the joints 230, 240 is excellent, so the defect rate was zero.

[0049] According to the ceramic susceptor and manufacturing method thereof according to the present invention, the bonding strength between the upper plate 220 and the lower plate 210 of the MMC metal ceramic composite base body 1100 can be improved by applying a multi-layer (active metal layer and aluminum layer) surface treatment between each plate of the upper plate 220 and the lower plate 210 of the base body and the brazing filler, thereby reducing the leak rate of He gas during the process in the semiconductor equipment, improving the degree of vacuum, and reducing the leakage of the coolant in the cooling passage, thereby maintaining a stable process and contributing to an improvement in yield. In the embodiment, it was confirmed that the leak rate of the He gas was reduced from the previous 1.0E-03 (mbar*l / s) to 2.0.E-08 (mbar*l / s) after the improvement.

[0050] 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]

[0051] 220 Upper Plate 321 1st active metal layer 322 1st Aluminum Layer 323 Brazing filler layer 210 Lower plate 215 Cooling Channel 211 Groove 311 Second active metal layer 312 2nd Aluminum Layer 1100 Base Body 1200 Insulation Plate

Claims

1. A method for manufacturing a base body of a ceramic susceptor, comprising the steps of: The base body includes a lower plate and an upper plate each made of a metal ceramic composite material, sequentially laminating a first active metal layer, a first aluminum layer, and a brazing filler layer on a bonding surface of the upper plate; sequentially laminating a second active metal layer and a second aluminum layer on the bonding surface of the lower plate; brazing the lower plate and the upper plate so that the first aluminum layer and the second aluminum layer are bonded to each other via the brazing filler layer; A method for manufacturing a ceramic susceptor base body comprising:

2. The method for manufacturing a base body of a ceramic susceptor according to claim 1 , further comprising a groove between the bonding surfaces of the lower plate.

3. The method for manufacturing a base body of a ceramic susceptor according to claim 1 , wherein the first active metal layer and the second active metal layer include at least one of Ti, Zr, Nb, Hf, and Ta.

4. 2. The method for manufacturing a base body of a ceramic susceptor according to claim 1, wherein the first active metal layer and the second active metal layer have a thickness of 1 to 5 μm.

5. 2. The method for manufacturing a base body of a ceramic susceptor according to claim 1, wherein the first aluminum layer and the second aluminum layer have a thickness of 5 to 10 μm.

6. A ceramic susceptor including a base body and an insulating plate, The base body includes a lower plate and an upper plate each made of a metal ceramic composite material and a joint therebetween; The joint is a first active metal layer, a first aluminum layer, and a brazing filler layer sequentially stacked on the upper plate; a second active metal layer and a second aluminum layer sequentially stacked on the lower plate, The lower plate and the upper plate are brazed together by the brazing filler layer, forming a ceramic susceptor.

7. The ceramic susceptor of claim 6 , wherein the bond is formed between cooling channels of the base body.

8. The ceramic susceptor of claim 6 , wherein the first active metal layer and the second active metal layer include at least one of Ti, Zr, Nb, Hf, and Ta.

9. 7. The ceramic susceptor according to claim 6, wherein the first active metal layer and the second active metal layer have a thickness of 1 to 5 μm.

10. 7. The ceramic susceptor according to claim 6, wherein the first aluminum layer and the second aluminum layer have a thickness of 5 to 10 μm.

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