Welding method of semiconductor cavity cover plate

Abstract

The invention provides a welding method of a semiconductor cavity cover plate, which comprises the following steps of: (1) cleaning the cavity cover plate, and then forming at least one plug welding hole to obtain a welding blank; and (2) the welding blank obtained in the step (1) is degreased and cleaned, and then self-fusion welding is conducted. The plug welding holes are added on the basis of welding, self-fusion welding is adopted, auxiliary welding flux or filler does not need to be added in the welding process, the workpieces are firmly welded together under the high-temperature condition after the self-fusion temperature of the materials of the workpieces is reduced, and the strength and appearance of welding seams can be effectively ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of metal processing and relates to a metal welding method, in particular to a welding method for a semiconductor cavity cover plate. Background Art

[0002] The semiconductor manufacturing process has extremely high requirements for the production environment and equipment precision, and is usually prepared in a vacuum chamber. A vacuum chamber is a pressure vessel that maintains a vacuum environment inside. At present, the main materials used to manufacture vacuum chambers are stainless steel, titanium alloy, etc. In recent years, with the rapid development of the semiconductor industry, aluminum alloy has become the main material for semiconductor vacuum chamber manufacturing due to its good corrosion resistance, weldability and processability.

[0003] In the existing technical solutions, the welding manufacturing of the cavity mainly includes tungsten inert gas arc welding (TIG welding) and stir friction welding. In the process of thick plate welding, tungsten inert gas arc welding usually requires a larger groove and multi-layer and multi-pass welding to complete the welding of the cavity. Stir friction welding technology has high requirements for tooling during the welding of thick plates. It requires internal support and external tightening tooling, and tooling support for the top forging pressure surface. At the same time, arc starting and arc ending tooling are required, and the requirements for tooling and clamping equipment are relatively strict.

[0004] The existing technology has the following deficiencies: (1) When TIG is used to weld thick plates, the plate processing groove size is large, the number of welding layers and passes is large, the welding speed is slow, the efficiency is low, and the cost is high; (2) When TIG welding is used, the heat input is large, the joint softens severely after welding, the strength is reduced, the cavity is deformed greatly after welding, and the precision is reduced; (3) When TIG welding is used, the weld is too concentrated and the deformation is serious after welding; (4) When TIG welding is used, there is a risk of tungsten clamping and pores when the top end of the weld is rotated; (5) Stir friction welding has high requirements for the assembly accuracy of parts; (6) After stir friction welding, there is a keyhole, which needs to be processed, reducing efficiency; (7) Stir friction welding requires a large top forging pressure during the thick plate welding process, and has strict requirements on the rigidity of the tooling and the stirring head clamping equipment; (8) The existence of the stirring head shoulder has strict requirements on the width of the welding materials on both sides of the weld, and the weldable structure is small and the flexibility is poor; (9) The existing technology has a low degree of automation, lacks online detection and real-time monitoring functions for weld quality, lacks inspection of welding quality, and has low efficiency of post-weld repair. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention aims to provide a method for welding a semiconductor cavity cover plate. The welding method can effectively reduce welding deformation, ensure the beautiful welding appearance of the semiconductor cavity and improve efficiency.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] The present invention provides a welding method for a semiconductor cavity cover plate, the welding method comprising the following steps:

[0008] (1) cleaning the cavity cover plate, and then setting at least one plug welding hole to obtain a welding blank;

[0009] (2) The welding blank obtained in step (1) is degreased and cleaned, and then autogenous welding is performed.

[0010] It is worth noting that the semiconductor cavity includes an upper disk surface, a lower disk surface and a cylindrical outer disk surface. The upper disk surface and the lower disk surface are arranged opposite to each other and cooperate to form an internal water channel for accommodating cooling water. In the present invention, the upper disk surface and the lower disk surface are collectively referred to as the semiconductor cavity cover plate.

[0011] The present invention adds a plug welding structure on the basis of welding, and adopts self-melting welding. No auxiliary flux or filler needs to be added during the welding process. Under high temperature conditions, the workpieces are firmly welded together after the self-melting temperature of the material of the workpieces themselves is reduced, which can effectively ensure the strength and appearance of the weld.

[0012] The autogenous welding provided by the present invention can, on the one hand, further heat the temperature of the edge of the cavity cover plate by cold pulse current, and on the other hand, the welding method can effectively reduce the deformation, ensure the beautiful welding appearance and improve the efficiency.

[0013] As a preferred technical solution of the present invention, the cavity cover plate in step (1) comprises a cover plate and a disc having a cavity.

[0014] Preferably, the disc is provided with a water retaining strip and a cavity for loading the water channel.

[0015] Preferably, the water retaining strip is used to prevent water in the waterway from escaping from the cavity.

[0016] Preferably, the cavity and the cover plate have the same size.

[0017] Preferably, the depth of the cavity is 4 to 6 mm, for example, 4 mm, 4.4 mm, 4.8 mm, 5.2 mm, 5.6 mm or 6 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0018] The welding method of the present invention is to weld the disc and the cover plate together by plug welding + autogenous welding. The cover plate and the cavity can be assembled together to form a semiconductor cavity cover plate.

[0019] As a preferred technical solution of the present invention, the material of the disk and the cover plate in step (1) are both aluminum alloy.

[0020] Preferably, the grade of the aluminum alloy includes any one of SUS316L, SUS304 or SUS316LVV.

[0021] Preferably, the diameter of the disc is 600-1200 mm, for example, 600 mm, 700 mm, 800 mm, 900 mm, 1000 mm, 1100 mm or 1200 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0022] Preferably, the maximum diameter of the cover plate is 140-160 mm, for example, 140 mm, 144 mm, 148 mm, 152 mm, 156 mm or 160 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0023] As a preferred technical solution of the present invention, the plug welding hole in step (1) comprises a truncated cone hole.

[0024] Preferably, the spacing between two adjacent plug welding holes is 90-110 mm, for example, 90 mm, 95 mm, 100 mm, 105 mm or 110 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0025] Preferably, the inner diameter of the plug welding hole is 5 to 10 mm, for example, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm or 10 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0026] As a preferred technical solution of the present invention, the number of the plug welding holes in step (1) is 6 to 10, for example, 6, 7, 8, 9 or 10.

[0027] Preferably, the plug welding hole is arranged on the water retaining strip of the disc.

[0028] As a preferred technical solution of the present invention, the cleaning treatment in step (1) includes acid washing, water washing and drying treatment performed in sequence.

[0029] As a preferred technical solution of the present invention, the degreasing cleaning in step (2) includes: using a degreasing solution for ultrasonic vibration cleaning.

[0030] As a preferred technical solution of the present invention, the mass ratio of the degreasing agent to water in the degreasing solution is 1:(180-200), for example, it can be 1:180, 1:185, 1:190, 1:195 or 1:200, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0031] Preferably, the temperature of the degreasing cleaning is 45-55°C, for example, it can be 45°C, 46°C, 47°C, 48°C, 49°C, 50°C, 51°C, 52°C, 53°C, 54°C or 55°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] Preferably, the degreasing and cleaning time is 30 to 60 minutes, for example, it can be 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes or 60 minutes, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0033] As a preferred technical solution of the present invention, the welding temperature of the autogenous welding in step (2) is 100-150°C, for example, it can be 100°C, 110°C, 120°C, 130°C, 140°C or 150°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0034] Preferably, the welding speed of the autogenous welding in step (2) is 1.5 to 2.5 cm / s, for example, it can be 1.5 cm / s, 1.7 cm / s, 1.9 cm / s, 2.1 cm / s, 2.3 cm / s or 2.5 cm / s, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0035] It is worth noting that the welding speed of the autogenous welding described in the present invention is 1.5-2.5 cm / s. A welding speed that is too fast will result in insufficient penetration and welding strength, while a welding speed that is too slow will cause serious deformation of the workpiece.

[0036] Preferably, the welding current of the autogenous welding in step (2) is 140-160A, for example, it can be 140A, 144A, 148A, 152A, 156A or 160A, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0037] It is worth noting that the autogenous welding in step (2) also includes passivation treatment, grinding treatment, ultrasonic cleaning and drying treatment.

[0038] Among them, the passivation treatment is to use a passivation liquid to treat the weld to remove the oxidation color of the weld; the grinding treatment is used to improve the flatness of the semiconductor cavity cover; and the ultrasonic cleaning is used for degreasing and cleaning.

[0039] As a preferred technical solution of the present invention, the welding method of the semiconductor cavity cover provided by the present invention comprises the following steps:

[0040] (1) The cavity cover plate is pickled, washed and dried, and then 6 to 10 plug welding holes are set on the water retaining strip of the cavity cover plate to obtain a welding blank;

[0041] The cavity cover plate includes a cover plate made of aluminum alloy and a disc with a cavity; the disc with a diameter of 600-1200 mm is provided with a water retaining strip and a cavity for loading a waterway; the cavity and the cover plate have the same size; the depth of the cavity is 4-6 mm;

[0042] The plug welding hole is in the shape of a truncated cone; the distance between two adjacent plug welding holes is 90 to 110 mm, and the inner diameter is 5 to 10 mm;

[0043] (2) degreasing and cleaning the welding blank obtained in step (1), and then performing autogenous welding;

[0044] The degreasing cleaning comprises: using a degreasing solution to perform ultrasonic vibration cleaning for 30 to 60 minutes at a temperature of 45 to 55° C.; the mass ratio of the degreasing agent to water in the degreasing solution is 1:(180 to 200);

[0045] The welding temperature of the autogenous welding is 100-150° C., the welding speed is 1.5-2.5 cm / s, and the welding current is 140-160A.

[0046] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. Through the following preferred technical solutions, the objectives and beneficial effects of the present invention can be better achieved and realized.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] (1) The present invention welds the cavity cover plate by plug welding + autogenous welding, which can effectively reduce deformation, ensure beautiful welding appearance and improve efficiency;

[0049] (2) The welding method provided by the present invention can meet the sealing requirements of the processed sealing surface;

[0050] (3) The welding method provided by the present invention has low cost, high welding efficiency, and avoids potential safety hazards. DETAILED DESCRIPTION

[0051] For the convenience of understanding the present invention, the present invention lists the following embodiments. 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.

[0052] Example 1

[0053] This embodiment provides a welding method for a semiconductor chamber cover plate, the welding method comprising the following steps:

[0054] (1) The cavity cover plate is pickled, washed and dried, and then 8 plug welding holes are set on the water retaining strip of the cavity cover plate to obtain a welding blank;

[0055] The cavity cover plate includes a cover plate made of aluminum alloy and a disc with a cavity; the disc with a diameter of 1000 mm is provided with a water retaining strip and a cavity for loading the waterway; the cavity and the cover plate have the same size; the depth of the cavity is 5 mm;

[0056] The plug welding hole is in the shape of a truncated cone; the distance between two adjacent plug welding holes is 100 mm, and the inner diameter is 7.5 mm;

[0057] (2) degreasing and cleaning the welding blank obtained in step (1), and then performing autogenous welding;

[0058] The degreasing cleaning comprises: using a degreasing solution to perform ultrasonic vibration cleaning for 45 minutes at a temperature of 50° C.; the mass ratio of the degreasing agent to water in the degreasing solution is 1:190;

[0059] The welding temperature of the autogenous welding is 125° C., the welding speed is 2 cm / s, and the welding current is 150A.

[0060] Example 2

[0061] This embodiment provides a welding method for a semiconductor chamber cover plate, the welding method comprising the following steps:

[0062] (1) The cavity cover plate is pickled, washed and dried, and then 6 plug welding holes are set on the water retaining strip of the cavity cover plate to obtain a welding blank;

[0063] The cavity cover plate includes a cover plate made of aluminum alloy and a disc with a cavity; the disc with a diameter of 600 mm is provided with a water retaining strip and a cavity for loading a waterway; the cavity and the cover plate have the same size; the depth of the cavity is 4 mm;

[0064] The plug welding hole is in the shape of a truncated cone; the distance between two adjacent plug welding holes is 90 mm, and the inner diameter is 5 mm;

[0065] (2) degreasing and cleaning the welding blank obtained in step (1), and then performing autogenous welding;

[0066] The degreasing cleaning comprises: using a degreasing solution to perform ultrasonic vibration cleaning for 60 minutes at a temperature of 45° C.; the mass ratio of the degreasing agent to water in the degreasing solution is 1:200;

[0067] The welding temperature of the autogenous welding is 100° C., the welding speed is 1.5 cm / s, and the welding current is 160A.

[0068] Example 3

[0069] This embodiment provides a welding method for a semiconductor chamber cover plate, the welding method comprising the following steps:

[0070] (1) The cavity cover plate is pickled, washed and dried, and then 10 plug welding holes are set on the water retaining strip of the cavity cover plate to obtain a welding blank;

[0071] The cavity cover plate includes a cover plate made of aluminum alloy and a disc with a cavity; the disc with a diameter of 1200 mm is provided with a water retaining strip and a cavity for loading a waterway; the cavity and the cover plate have the same size; the depth of the cavity is 6 mm;

[0072] The plug welding hole is in the shape of a truncated cone; the distance between two adjacent plug welding holes is 110 mm, and the inner diameter is 10 mm;

[0073] (2) degreasing and cleaning the welding blank obtained in step (1), and then performing autogenous welding;

[0074] The degreasing cleaning comprises: using a degreasing solution to perform ultrasonic vibration cleaning for 30 minutes at a temperature of 55° C.; the mass ratio of the degreasing agent to water in the degreasing solution is 1:180;

[0075] The welding temperature of the autogenous welding is 150° C., the welding speed is 2.5 cm / s, and the welding current is 140A.

[0076] Example 4

[0077] This embodiment provides a welding method for a semiconductor chamber cover plate, the welding method comprising the following steps:

[0078] (1) The cavity cover plate is pickled, washed and dried, and then 8 plug welding holes are set on the water retaining strip of the cavity cover plate to obtain a welding blank;

[0079] The cavity cover plate includes a cover plate made of aluminum alloy and a disc with a cavity; the disc with a diameter of 800 mm is provided with a water retaining strip and a cavity for loading a waterway; the cavity and the cover plate have the same size; the depth of the cavity is 4.5 mm;

[0080] The plug welding hole is in the shape of a truncated cone; the distance between two adjacent plug welding holes is 92 mm, and the inner diameter is mm;

[0081] (2) degreasing and cleaning the welding blank obtained in step (1), and then performing autogenous welding;

[0082] The degreasing cleaning comprises: using a degreasing solution to perform ultrasonic vibration cleaning for 50 minutes at a temperature of 52° C.; the mass ratio of the degreasing agent to water in the degreasing solution is 1:195;

[0083] The welding temperature of the autogenous welding is 120° C., the welding speed is 2.2 cm / s, and the welding current is 158A.

[0084] Example 5

[0085] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0086] In this embodiment, the welding temperature of the autogenous welding in step (2) is adjusted to 80°C.

[0087] Example 6

[0088] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0089] In this embodiment, the welding temperature of the autogenous welding in step (2) is adjusted to 160°C.

[0090] Example 7

[0091] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0092] In this embodiment, the welding speed of the autogenous welding in step (2) is adjusted to 1.2 cm / s.

[0093] Example 8

[0094] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0095] In this embodiment, the welding speed of the autogenous welding in step (2) is adjusted to 2.8 cm / s.

[0096] Example 9

[0097] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0098] In this embodiment, the welding current of the autogenous welding in step (2) is adjusted to 120A.

[0099] Example 10

[0100] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0101] In this embodiment, the welding current of the autogenous welding in step (2) is adjusted to 180A.

[0102] Embodiment 11

[0103] This embodiment provides a welding method for a semiconductor chamber cover plate. The difference between the welding method and the embodiment 1 is that:

[0104] In this embodiment, the number of the plug welding holes in step (1) is adjusted to 4.

[0105] Comparative Example 1

[0106] This comparative example provides a method for welding a semiconductor cavity cover plate, the welding method comprising:

[0107] The cavity cover is pickled, washed with water and dried, and then argon arc welding is performed on both sides of the water retaining strip of the cavity cover under argon protection.

[0108] Comparative Example 2

[0109] This comparative example provides a method for welding a semiconductor cavity cover plate, and the difference between the welding method and Example 1 is only that:

[0110] In this comparative example, the autogenous welding in step (2) is adjusted to brazing.

[0111] Comparative Example 3

[0112] This comparative example provides a method for welding a semiconductor cavity cover plate, and the difference between the welding method and Example 1 is only that:

[0113] In this comparative example, the process of setting the plug welding hole described in step (1) is omitted.

[0114] Performance Testing:

[0115] The semiconductor cavity cover plate obtained by the methods provided in the above embodiments and comparative examples was subjected to the following performance tests, and the results are shown in Table 1.

[0116] Table 1

[0117]

[0118]

[0119] From Table 1, we can get the following points:

[0120] (1) Analysis of Examples 1-4 shows that the semiconductor cavity cover plate obtained by the welding method provided by the present invention has a small deformation amount, a high yield rate, and excellent welding strength;

[0121] (2) Analysis of Example 1 and Examples 5-10 shows that the welding temperature, welding speed and welding current in the autogenous welding process will affect the welding effect;

[0122] More specifically, when the welding speed is too fast, it will lead to insufficient penetration and insufficient welding strength, and when the welding speed is too slow, it will cause serious deformation of the workpiece;

[0123] (3) It can be seen from the analysis of Example 1 and Comparative Example 1 that when argon arc welding is used for welding, the semiconductor cavity cover plate is severely deformed, the flatness is significantly reduced, and the bonding strength is also reduced;

[0124] (4) Analysis of Example 1 and Comparative Example 2 shows that when brazing is used for welding, the semiconductor cavity cover plate is severely deformed and the flatness is significantly reduced.

[0125] In summary, the present invention adds a plug welding structure on the basis of welding and adopts autogenous welding. No auxiliary flux or filler needs to be added during the welding process. Under high temperature conditions, the workpieces can be firmly welded together after the autogenous melting temperature of the material of the workpieces themselves is reduced, which can effectively ensure the strength and appearance of the weld.

[0126] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for welding a semiconductor chamber cover, characterized in that: The welding method comprises the following steps: (1) cleaning the cavity cover plate, and then setting at least one plug welding hole to obtain a welding blank; (2) The welding blank obtained in step (1) is degreased and cleaned, and then autogenous welding is performed.

2. The welding method according to claim 1, characterized in that: The cavity cover plate in step (1) comprises a cover plate and a disc; Preferably, the disc is provided with a water retaining strip and a cavity for loading the waterway; Preferably, the water retaining strip is used to prevent water in the waterway from escaping from the cavity; Preferably, the cavity and the cover plate have the same size; Preferably, the depth of the cavity is 4-6 mm.

3. The welding method according to claim 2, characterized in that: The materials of the disc and the cover plate in step (1) are both aluminum alloy; Preferably, the grade of the aluminum alloy includes any one of SUS316L, SUS304 or SUS316LVV; Preferably, the diameter of the disc is 600-1200 mm.

4. The welding method according to any one of claims 1 to 3, characterized in that: The plug welding hole in step (1) comprises a truncated cone hole; Preferably, the distance between two adjacent plug welding holes is 90 to 110 mm; Preferably, the inner diameter of the plug welding hole is 5 to 10 mm.

5. The welding method according to claim 2, characterized in that: The number of the plug welding holes in step (1) is 6 to 10; Preferably, the plug welding hole is arranged on the water retaining strip of the disc.

6. The welding method according to any one of claims 1 to 5, characterized in that: The cleaning process in step (1) includes pickling, water washing and drying in sequence.

7. The welding method according to any one of claims 1 to 6, characterized in that: The degreasing cleaning in step (2) includes: using a degreasing solution to perform ultrasonic vibration cleaning.

8. The welding method according to claim 7, characterized in that: The mass ratio of the degreasing agent to water in the degreasing solution is 1:(180-200); Preferably, the temperature of the degreasing cleaning is 45-55°C; Preferably, the degreasing and cleaning time is 30 to 60 minutes.

9. The welding method according to any one of claims 1 to 8, characterized in that: The welding temperature of the autogenous welding in step (2) is 100-150° C. Preferably, the welding speed of the autogenous welding in step (2) is 1.5 to 2.5 cm / s; Preferably, the welding current of the autogenous welding in step (2) is 140-160A.

10. The welding method according to any one of claims 1 to 9, characterized in that: The welding method comprises the following steps: (1) The cavity cover plate is pickled, washed and dried, and then 6 to 10 plug welding holes are set on the water retaining strip of the cavity cover plate to obtain a welding blank; The cavity cover plate includes a cover plate made of aluminum alloy and a disc with a cavity; the disc with a diameter of 600-1200 mm is provided with a water retaining strip and a cavity for loading the waterway; the cavity and the cover plate have the same size; the depth of the cavity is 4-6 mm; the water retaining strip is used to prevent water in the waterway from escaping the cavity; The plug welding hole is in the shape of a truncated cone; the distance between two adjacent plug welding holes is 90 to 110 mm, and the inner diameter is 5 to 10 mm; (2) degreasing and cleaning the welding blank obtained in step (1), and then performing autogenous welding; The degreasing cleaning comprises: using a degreasing solution to perform ultrasonic vibration cleaning for 30 to 60 minutes at a temperature of 45 to 55°C; The mass ratio of the degreasing agent to water in the degreasing solution is 1:(180-200); The welding temperature of the autogenous welding is 100-150° C., the welding speed is 1.5-2.5 cm / s, and the welding current is 140-160A.

Images