C-SiC target material brazing method, C-SiC target material brazing product and application of C-SiC target material brazing product

Abstract

The invention provides a brazing method of a C-SiC target material, a C-SiC target material brazing product and application of the C-SiC target material brazing product. The brazing method comprises the steps that the C-SiC target material is placed on a heating face of a heating device, after the surface of the side, away from the heating face, of the C-SiC target material is covered with a heat conduction insulating part, heating is conducted, brazing is conducted, and the C-SiC target material brazing product is obtained. According to the brazing method provided by the invention, the surface of the C-SiC target material is covered with the heat-conducting insulating part while heating is carried out, and gas in the C-SiC target material is fully dried in the reheating process, so that the infiltration difficulty is reduced, the brazing combination difficulty is reduced, and the brazing qualification rate is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of brazing, and relates to a brazing method for a C-SiC target material, and in particular to a brazing method for a C-SiC target material, a C-SiC target material brazing product and an application thereof. Background Art

[0002] Brazing is a welding technology that uses a brazing filler metal with a lower melting point than the base metal, and an operating temperature that is lower than the melting point of the base metal but higher than the melting point of the brazing liquid, to connect the base metals together through the molten brazing filler metal.

[0003] C-SiC target welding is usually carried out by brazing. However, due to the easy powder loss and extremely difficult infiltration during infiltration, large-area welding defects and welding failures often occur. In the prior art, high-power ultrasonic infiltration and increased infiltration time are used to enhance the qualified rate of C-SiC target welding. However, after using high-power ultrasonic infiltration and increasing the infiltration time, the qualified rate is still unstable.

[0004] CN114799391A discloses a method for welding a silicon carbide target material, the welding method comprising the following steps: (1) pre-treating a target blank and a backing plate to obtain a pre-treated target material; the material of the target blank is silicon carbide; (2) vacuum brazing the pre-treated target material obtained in step (1), wherein the solder for the vacuum brazing treatment is a silver-based welding sheet, to obtain the silicon carbide target material.

[0005] CN111195768A discloses a welding method for a C-SiC sputtering target, the method comprising the following steps: (1) shielding the C-SiC target and a back plate, then placing solder on the welding surface of the shielded C-SiC target and the back plate and heating them, and after heating, performing an infiltration treatment on the welding surface of the C-SiC and the back plate to obtain the treated C-SiC target and the back plate; (2) setting a molten pool on the treated back plate obtained in step (1) and placing solder and setting copper wires at equal intervals to obtain a treated back plate; (3) buckling, assembling and welding the treated C-SiC target obtained in step (1) and the treated back plate obtained in step (2).

[0006] CN110330356A discloses a method for brazing and connecting silicon carbide ceramics, and relates to a method for brazing and connecting silicon carbide ceramics. The purpose of the invention is to solve the problems of poor wettability of metal brazing materials, large residual stress, and small weldable workpieces in traditional brazing methods. Method: Al2O3, SiO2, and CaO or CaCO3 are mixed, dried after grinding, melted, quenched with water, and then ground, sieved, and dried to obtain microcrystalline glass brazing materials; the silicon carbide ceramics to be brazed are pretreated to obtain pretreated silicon carbide ceramics; the microcrystalline glass brazing materials are evenly mixed with a binder and then applied between the pretreated silicon carbide ceramics to obtain silicon carbide ceramics to be welded connecting parts; the silicon carbide ceramics to be welded connecting parts are brazed, and then cooled with the furnace to obtain silicon carbide ceramics after brazing.

[0007] The brazing methods of C-SiC targets disclosed in the prior art all have certain defects and a low brazing pass rate. Therefore, it is very important to develop and design a new brazing method of C-SiC targets and a C-SiC target brazing product. Summary of the invention

[0008] In view of the deficiencies in the prior art, the object of the present invention is to provide a C-SiC target brazing method, a C-SiC target brazing product and applications thereof. The brazing method provided by the present invention covers the surface of the C-SiC target with a heat-conductive insulating member while heating, and fully dries the gas inside the C-SiC target during the reheating process, thereby reducing the difficulty of wetting and the difficulty of brazing, thereby improving the brazing qualification rate.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a brazing method for a C-SiC target, the brazing method comprising:

[0011] The C-SiC target is placed on the heating surface of the heating device, and after covering the surface of the C-SiC target away from the heating surface with a heat-conducting insulating member, it is heated and then brazed to obtain a C-SiC target brazing product.

[0012] The brazing method provided by the present invention covers the surface of the C-SiC target material with a heat-conductive insulating member while heating, and fully dries the gas inside the C-SiC target material during the reheating process, thereby reducing the difficulty of wetting and the difficulty of brazing, thereby improving the brazing qualification rate.

[0013] The brazing method in the present invention is a method in the prior art, and any brazing method disclosed in the prior art can be applied.

[0014] The brazing method disclosed in the prior art may be, for example: (1) machining the target blank and the backing plate in sequence, wherein the flatness of the target blank after machining is less than 0.2 mm, and the flatness of the backing plate after machining is less than 0.2 mm, and then cleaning with acetone for 3 to 15 minutes, and then cleaning with isopropanol for 10 to 30 minutes, and then placing the silver-based solder sheet and the target blank in the welding groove of the backing plate in sequence and vacuum packaging to obtain a pre-treated target material; the material of the target blank is silicon carbide. (2) vacuuming the pre-treated target material obtained in step (1) until the terminal vacuum degree is 1×10 -2 ~6×10 -2 Pa, and then the target blank of the pretreated target material is placed upward and horizontally in a graphite tray of a vacuum brazing furnace, the flatness of the graphite tray is ≤0.5mm, and ceramic blocks are evenly placed on the target blank of the pretreated target material at the same height, and the mass of the ceramic blocks is 20-50kg. Then, a vacuum brazing treatment is performed using a silver-based welding sheet as a solder, wherein the silver-based welding sheet contains Ag and Cu; the mass percentage of silver in the silver-based welding sheet is 70-80%; the thickness of the silver-based welding sheet is 0.02-0.1mm; the vacuum brazing treatment includes first reaching 500-600°C at a heating rate of 4-9°C / min and keeping warm for 40-60min; then reaching 820-920°C at a heating rate of 2-6°C / min and keeping warm for 10-50min; finally cooling to 180-200°C at a cooling rate of 1-5°C / min to obtain the silicon carbide target material.

[0015] The brazing method disclosed in the prior art may also be, for example: (1) shielding the C-SiC target and the back plate, then placing solder on the welding surface of the shielded C-SiC target and the back plate and heating them, and after heating, performing a wetting treatment on the welding surface of the C-SiC and the back plate to obtain the treated C-SiC target and the back plate; the shielding treatment is to use a heat-resistant tape to shield the non-welding surface; the amount of solder added is 0.5 to 1 kg; the solder is indium solder; the terminal temperature of the heating is 200 to 240°C; the wetting treatment is performed using an ultrasonic brazing machine; the power of the ultrasonic brazing machine is 1000 to 1400 W; the wetting treatment time is 20 to 40 minutes; after the wetting treatment, the oxidized solder on the surface of the solder is removed; (2) a molten pool is set on the treated back plate obtained in step (1) and solder is placed at equal intervals Copper wire is arranged to obtain a treated backplane; the area of ​​the molten pool is the same as the area of ​​the backplane; the height of the molten pool is 3 to 5 mm; the amount of solder added in the molten pool is 2 to 3 mm higher than the welding surface of the backplane; the solder in the molten pool is indium solder; the diameter of the copper wire is 0.2 to 0.5 mm; the number of copper wires arranged is at least 3; (3) the treated C-SiC target obtained in step (1) and the treated backplane obtained in step (2) are assembled and welded; the welding is performed at 200 to 240°C; the welding time is 10 to 120 s; wherein the method further comprises placing the complete target on a platform with a horizontal surface after the target is cooled to 100 to 130°C with the furnace after welding, wherein the sputtering surface of the C-SiC target is in contact with the surface of the platform, and the two ends of the backplane are fastened to the platform using a C-type clamp, and then cooled to room temperature.

[0016] Preferably, the heating device comprises a heating furnace.

[0017] Preferably, the heating surface is in contact with a surface of the C-SiC target material on one side close to the heating device.

[0018] Preferably, the thermally conductive insulating member comprises a thermally conductive insulating cloth.

[0019] Preferably, the covering includes covering the entire surface of the C-SiC target away from the heating surface with a thermally conductive insulating member.

[0020] Preferably, the heating temperature is 210-230°C, for example, it can be 210°C, 212°C, 214°C, 216°C, 218°C, 220°C, 224°C, 226°C, 228°C or 230°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0021] Preferably, the heating time is not less than 12 h, for example, it can be 12 h, 13 h, 14 h, 15 h, 16 h, 17 h, 18 h, 19 h, 20 h, 21 h, 22 h, 23 h, 24 h, 25 h or 26 h, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] As a preferred technical solution of the brazing method of the present invention, the brazing method comprises:

[0023] A C-SiC target is placed on a heating surface of a heating furnace, the heating surface is fitted with a surface of the C-SiC target on one side close to the heating device, and after covering the entire surface of the C-SiC target away from the heating surface with a thermally conductive insulating cloth, it is heated at 210-230° C. for not less than 12 hours, and then brazed to obtain a C-SiC target brazing product.

[0024] In a second aspect, the present invention provides a C-SiC target brazing product, wherein the C-SiC target brazing product is obtained by the brazing method described in the first aspect.

[0025] In a third aspect, the present invention provides an application of the C-SiC target brazing product described in the second aspect, wherein the C-SiC target brazing product is used for semiconductor manufacturing.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The brazing method provided by the present invention covers the surface of the C-SiC target material with a heat-conductive insulating member while heating, and fully dries the gas inside the C-SiC target material during the reheating process, thereby reducing the difficulty of wetting and the difficulty of brazing, thereby improving the brazing qualification rate. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0029] Example 1

[0030] This embodiment provides a brazing method for a C-SiC target material, the brazing method comprising:

[0031] A C-SiC target is placed on a heating surface of a heating furnace, the heating surface is fitted with a surface of the C-SiC target on one side close to the heating device, and after covering the entire surface of the C-SiC target away from the heating surface with a thermally conductive insulating cloth, it is heated at 220° C. for 15 hours and then brazed to obtain a C-SiC target brazing product.

[0032] Example 2

[0033] This embodiment provides a brazing method for a C-SiC target material, the brazing method comprising:

[0034] A C-SiC target is placed on the heating surface of a heating furnace, the heating surface is in contact with the surface of the C-SiC target on one side close to the heating device, and after the entire surface of the C-SiC target away from the heating surface is covered with a thermally conductive insulating cloth, it is heated at 215°C for 18 hours and then brazed to obtain a C-SiC target brazing product.

[0035] Example 3

[0036] This embodiment provides a brazing method for a C-SiC target material, the brazing method comprising:

[0037] A C-SiC target is placed on the heating surface of a heating furnace, the heating surface is fitted with a surface of the C-SiC target on one side close to the heating device, and after the entire surface of the C-SiC target away from the heating surface is covered with a thermally conductive insulating cloth, it is heated at 218°C for 14 hours and then brazed to obtain a C-SiC target brazing product.

[0038] Example 4

[0039] This embodiment provides a brazing method for a C-SiC target material, the brazing method comprising:

[0040] A C-SiC target is placed on the heating surface of a heating furnace, the heating surface is in contact with the surface of the C-SiC target on one side close to the heating device, and after the entire surface of the C-SiC target away from the heating surface is covered with a thermally conductive insulating cloth, it is heated at 210°C for 20 hours and then brazed to obtain a C-SiC target brazing product.

[0041] Example 5

[0042] This embodiment provides a brazing method for a C-SiC target material, the brazing method comprising:

[0043] A C-SiC target is placed on a heating surface of a heating furnace, the heating surface is fitted with a surface of the C-SiC target on one side close to the heating device, and a thermally conductive insulating cloth is covered on the entire surface of the C-SiC target away from the heating surface, and then heated at 230°C for 12 hours, and then brazed to obtain a C-SiC target brazing product.

[0044] Example 6

[0045] This embodiment provides a brazing method for a C-SiC target, which is the same as that of Embodiment 1 except that a thermally conductive insulating cloth is covered on half of the surface of the C-SiC target away from the heating surface in the brazing method.

[0046] Example 7

[0047] This embodiment provides a brazing method for a C-SiC target, which is the same as that of Embodiment 1 except that in the brazing method, two-thirds of the surface of the C-SiC target away from the heating surface is covered with a thermally conductive insulating cloth.

[0048] Example 8

[0049] This embodiment provides a brazing method for a C-SiC target material, which is the same as that of Embodiment 1 except that the brazing method is heated at 200°C.

[0050] Example 9

[0051] This embodiment provides a brazing method for a C-SiC target material, which is the same as that of Embodiment 1 except that the brazing method is heated at 240°C.

[0052] Example 10

[0053] This embodiment provides a brazing method for a C-SiC target material, which is the same as that of Embodiment 1 except that the heating time in the brazing method is 8 hours.

[0054] Embodiment 11

[0055] This embodiment provides a brazing method for a C-SiC target material, which is the same as that of Embodiment 1 except that the heating time in the brazing method is 11 hours.

[0056] Comparative Example 1

[0057] This comparative example provides a brazing method for a C-SiC target, which is the same as Example 1 except that the step of covering the entire surface of the C-SiC target away from the heating surface with a thermally conductive insulating cloth is omitted.

[0058] Comparative Example 2

[0059] This comparative example provides a brazing method for a C-SiC target material, which is the same as Example 1 except that the steps before brazing in the brazing method are omitted.

[0060] C-SiC target brazing products were prepared by the brazing methods of the C-SiC target provided in the above embodiments and comparative examples, and the qualified rates of the C-SiC target brazing products were statistically analyzed. The qualified rates of the C-SiC target brazing products are shown in Table 1.

[0061] Table 1

[0062] Welding pass rate (%) Example 1 94 Example 2 93 Example 3 91 Example 4 95 Example 5 93 Example 6 87 Example 7 86 Example 8 84 Example 9 86 Example 10 85 Embodiment 11 87 Comparative Example 1 79 Comparative Example 2 74

[0063] From Table 1, we can get:

[0064] (1) The C-SiC target brazing products prepared by the C-SiC target brazing methods provided in Examples 1 to 5 of the present invention have a high welding pass rate;

[0065] (2) By comparing Example 1 with Examples 6 and 7, it can be seen that the area of ​​the surface of the C-SiC target material away from the heating surface in the present invention covered by the thermally conductive insulating cloth will affect the qualified rate of the C-SiC target material brazing products; when the area covered by the thermally conductive insulating cloth is relatively small, the qualified rate of the C-SiC target material brazing products will be relatively low, because the uncovered area is difficult to infiltrate;

[0066] (3) By comparing Example 1 with Examples 8 and 9, it can be seen that the heating temperature in the brazing method of the present invention affects the qualified rate of C-SiC target brazing products; when the heating temperature is low, the qualified rate of C-SiC target brazing products is low, which is due to incomplete melting of the solder; when the heating temperature is high, the qualified rate of C-SiC target brazing products is low, which is due to faster oxidation of the solder;

[0067] (4) By comparing Example 1 with Examples 10 and 11, it can be seen that the heating time in the brazing method of the present invention will affect the qualified rate of C-SiC target brazing products; when the heating time is too short, the qualified rate of C-SiC target brazing products will be too low, which is due to the uneven heating of the product and the low local temperature; when the heating time is too long, the qualified rate of C-SiC target brazing products will be too low, which is due to the generation of defects such as dissolution;

[0068] (5) By comparing Example 1 with Comparative Examples 1 and 2, it can be seen that the brazing method provided by the present invention covers the surface of the C-SiC target with a thermally conductive insulating member while heating, so that the gas inside the C-SiC target is fully dried during the reheating process, thereby reducing the difficulty of wetting and the difficulty of brazing, thereby improving the brazing qualification rate.

[0069] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A brazing method for a C-SiC target, characterized in that: The brazing method comprises: The C-SiC target is placed on the heating surface of the heating device, and after covering the surface of the C-SiC target away from the heating surface with a heat-conducting insulating member, it is heated and then brazed to obtain a C-SiC target brazing product.

2. The brazing method according to claim 1, characterized in that: The heating device comprises a heating furnace.

3. The brazing method according to claim 1 or 2, characterized in that: The heating surface is in contact with a surface of the C-SiC target material on one side close to the heating device.

4. The brazing method according to any one of claims 1 to 3, characterized in that: The thermally conductive insulating member comprises a thermally conductive insulating cloth.

5. The brazing method according to any one of claims 1 to 4, characterized in that: The covering includes covering the entire surface of the C-SiC target away from the heating surface with a thermally conductive insulating member.

6. The brazing method according to any one of claims 1 to 5, characterized in that: The heating temperature is 210-230°C.

7. The brazing method according to any one of claims 1 to 6, characterized in that: The heating time is not less than 12 hours.

8. The brazing method according to any one of claims 1 to 7, characterized in that: The brazing method comprises: A C-SiC target is placed on a heating surface of a heating furnace, the heating surface is fitted with a surface of the C-SiC target on one side close to the heating device, and after covering the entire surface of the C-SiC target away from the heating surface with a thermally conductive insulating cloth, it is heated at 210-230° C. for not less than 12 hours, and then brazed to obtain a C-SiC target brazing product.

9. A C-SiC target brazing product, characterized in that: The C-SiC target brazing product is obtained by the brazing method according to any one of claims 1 to 8.

10. An application of the C-SiC target brazing product according to claim 9, characterized in that: The C-SiC target brazing product is used in semiconductor manufacturing.