Aluminum positive back silver wafer surface evaporation device

Abstract

The utility model provides a kind of positive aluminium back silver wafer surface evaporation device, it is related to the technical field of semiconductor manufacturing.Surface evaporation device includes planet disc and first cover plate, the planet disc is provided with the plating area, wafer is placed in the plating area, the first cover plate covers in wafer front and is located the one side of planet disc towards evaporation machine inner cavity, the first cover plate surface is provided with aluminium plating area, the aluminium plating area is set to openwork structure.The utility model adds first cover plate in wafer front aluminium plating area, directly on first cover plate reserved openwork aluminium plating area, when carrying out aluminium plating, aluminium metal can be plated in openwork aluminium plating area corresponding wafer surface, the wafer surface corresponding to unopenwork area will not be plated aluminium metal.The utility model omits the photoresist technology of conventional front aluminium plating process, directly improves the splash problem of developing solution, gel-removing liquid in photoresist process, and the wafer aluminium plating area is plated with poor aluminium plating effect and affects wafer quality problem.

Description

Technical Field

[0001] This utility model relates to the technical field of semiconductor manufacturing, specifically to an apparatus for vapor deposition on the surface of a positive aluminum back silver wafer. Background Technology

[0002] Wafer evaporation is a technique that deposits metal onto the surface of a wafer, playing a crucial role in semiconductor manufacturing. The basic principle of wafer evaporation is to improve the wafer's conductivity, corrosion resistance, and mechanical strength by forming a thin metal film on the wafer surface. Currently, wafer evaporation technology is widely used in semiconductor manufacturing, electronic product manufacturing, and other fields.

[0003] Aluminum-on-aluminum back-silver wafers refer to wafers where an aluminum metal layer is deposited on the front side using aluminum vapor deposition, while a titanium-nickel-silver metal layer is deposited on the back side. Aluminum-on-aluminum back-silver wafers exhibit excellent conductivity, performing exceptionally well in high-frequency signal transmission. The aluminum metal layer on the front side possesses good ductility and plasticity, forming a dense and uniform alumina film in air, providing excellent corrosion resistance. Compared to copper or gold plating, aluminum-on-aluminum back-silver wafers have relatively lower production costs, making them suitable for mass production.

[0004] Currently, the surface metal evaporation process for silver-plated aluminum wafers is typically:

[0005] like Figure 1 , Figure 2 As shown, Step 1, Front (P-side) Aluminum Plating: The entire cavity of the existing aluminum vapor deposition machine contains aluminum. During front-side aluminum plating, the P-side of the wafer faces the inside of the cavity, and the back (N-side) of the wafer is covered with a cover plate to prevent aluminum metal from being plated on the N-side; Step 2, Coating: After the front-side aluminum plating is completed, a layer of photoresist is coated on the surface of the aluminum metal layer; Step 3, Exposure: According to the actual working conditions, a photolithographic pattern is drawn on the photoresist; Step 4, Development: Remove the photoresist in the areas on the P-side that do not need aluminum plating; Step 5, Aluminum Removal: Use aluminum removal solution to remove the aluminum metal in the areas where the photoresist was removed in Step 4; Step 6, Photoresist Removal: Remove all the photoresist on the surface of the P-side to complete the aluminum metal plating; Step 7, Aluminum Sintering: Aluminum is sintered into the silicon layer to form an alloy layer; Step 8, Back (N-side) Titanium-Nickel-Silver Plating: The N-side of the wafer faces the inside of the cavity, and the P-side of the wafer is covered with a cover plate to prevent titanium-nickel-silver plating on the P-side.

[0006] The aforementioned existing technologies have problems such as cumbersome operation procedures, long production process, low production efficiency, high raw material consumption costs, and the need for special treatment of waste liquid. In particular, when performing front-side aluminum plating, the developing solution and aluminum stripping solution both have splashing problems, which can easily corrode the areas where aluminum needs to be retained, thus affecting the quality of the wafer. Utility Model Content

[0007] (a) Technical problems to be solved

[0008] To address the shortcomings of existing technologies, this utility model provides a vapor deposition apparatus for the surface of aluminum back silver wafers. It solves the problems of cumbersome operation procedures, long production process, low production efficiency, high raw material consumption costs, and the need to add wastewater treatment procedures for metal waste liquid in existing technologies. In particular, it solves the technical problem that when aluminum is deposited on the front side, the developing solution and aluminum stripping solution both splash, which can easily corrode the areas where aluminum needs to be retained, thus affecting the quality of the wafers.

[0009] (II) Technical Solution

[0010] To achieve the above objectives, this utility model provides the following technical solution:

[0011] A vapor deposition apparatus for a positive aluminum back silver wafer includes a planetary disk and a first cover plate. The planetary disk has a deposition area, and the wafer is placed in the deposition area. The first cover plate covers the front of the wafer and is located on the side of the planetary disk facing the inner cavity of the vapor deposition machine. The surface of the first cover plate has an aluminum plating area, which is configured as a hollow structure.

[0012] Preferably, the first cover plate is a circular sheet structure with an annular groove on its curved surface. A magnetic ring is embedded in the annular groove, and a magnetic block is embedded in the side wall of the area to be plated. The magnetic block and the magnetic ring attract each other.

[0013] Preferably, the surface of the first cover plate has a groove, which is located at the edge of the first cover plate.

[0014] Preferably, a stepped groove is formed on the side wall of the area to be plated, and the wafer is placed in the stepped groove. The stepped groove divides the area to be plated into a first snap-fit ​​area and a second snap-fit ​​area in sequence from the first cover plate toward the wafer. The first cover plate snaps into the first snap-fit ​​area.

[0015] Preferably, it further includes a second cover plate, which is snapped into the second snap-fit ​​area.

[0016] Preferably, the second cover plate has a protrusion at its center for easy handling.

[0017] Preferably, the planetary disk is provided with a pressing mechanism, which includes a pressing plate and a fixing part connected to the planetary disk. One end of the pressing plate is rotatably connected to the fixing part, and the other end of the pressing plate presses against the surface of the second cover plate.

[0018] Preferably, the cross-section of the pressure plate is a zigzag shape, and the end away from the fixing part includes an abutting part, which is the lowest end of the pressure plate, and the abutting part abuts against the surface of the second cover plate.

[0019] Preferably, the fixing part includes a bolt that is rotatably fixed on the planetary disk, and the end of the pressure plate is fitted onto the bolt and rotatably connected to the bolt.

[0020] (III) Beneficial Effects

[0021] This invention provides a vapor deposition apparatus for the surface of a positive aluminum back silver wafer. Compared with the prior art, it has the following advantages:

[0022] This invention adds a first cover plate to the front of the wafer, and directly reserves a hollowed-out aluminum plating area on the first cover plate. When the planetary disk is placed in the evaporation machine for aluminum plating, aluminum metal can be plated on the wafer surface corresponding to the hollowed-out aluminum plating area. The area of ​​the first cover plate that is not hollowed out will cover the wafer and will not be plated with aluminum metal.

[0023] This invention eliminates the photoresist exposure, development, etching, and resist removal processes in traditional front-side aluminum plating. It directly improves the problem of poor aluminum plating in the wafer's aluminum plating area due to the splashing of developer and resist remover during the photoresist process, thus affecting wafer quality. The yield rate of the produced wafers is significantly improved, and the quality is guaranteed. This invention saves process steps, simplifies operation, reduces production processes, and significantly lowers production costs. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 The image shows the front view of a wafer after step 3 in the existing vapor deposition process in the background art.

[0026] Figure 2 This is a front view of a wafer after step 6 in the existing vapor deposition process in the background art.

[0027] Figure 3 This is a schematic diagram of the planetary disk in the vapor deposition machine according to an embodiment of the present invention;

[0028] Figure 4 This is a schematic cross-sectional view of the area to be plated on the planetary disk in an embodiment of this utility model;

[0029] Figure 5 This is a top view of the concave surface (including the first cover plate) of the planetary disk in an embodiment of the present invention;

[0030] Figure 6This is a cross-sectional structural diagram of the first cover plate in an embodiment of the present utility model;

[0031] Figure 7 This is a top view of the convex surface (including the second cover plate) of the planetary disk in an embodiment of the present invention;

[0032] Figure 8 This is a cross-sectional structural diagram of the pressing mechanism on the convex surface of the planetary disk in an embodiment of this utility model.

[0033] Among them, 1. Planetary disk; 11. Plated area; 111. Magnetic block; 112. Stepped groove; 1121. First snap-fit ​​area; 1122. Second snap-fit ​​area; 2. First cover plate; 21. Aluminum plating area; 22. Annular groove; 221. Magnetic ring; 23. Groove; 3. Second cover plate; 31. Protrusion; 4. Pressing mechanism; 41. Pressing plate; 411. Contact part; 42. Fixing part; 421. Bolt. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments of this utility model are described clearly and completely. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0035] This application provides a vapor deposition apparatus for aluminum back-silver wafers, solving problems such as cumbersome operation procedures, long production processes, low production efficiency, high raw material costs, and the need for additional wastewater treatment processes for metal waste liquids in existing technologies. In particular, it addresses the technical problem of splashing of developing solution and aluminum stripping solution during front-side aluminum deposition, which easily corrodes areas where aluminum needs to be retained, thus affecting wafer quality. By adding a first cover plate with a perforated aluminum deposition area on the first cover plate, the wafer can be directly deposited by covering the front side with the first cover plate, replacing the original photoresist exposure, development, etching, and photoresist removal processes. This simplifies operation, reduces production steps, saves production costs, and improves wafer quality.

[0036] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0037] Example:

[0038] like Figure 3 , Figure 4 , Figure 5 As shown, the vapor deposition apparatus for the surface of positive aluminum back silver wafers includes a planetary disk 1, a first cover plate 2, and a second cover plate 3.

[0039] During the plating process, the planetary disk 1 is fixed inside the vapor deposition machine, and aluminum metal is coated inside the machine's cavity. The planetary disk 1 has a spherical structure, including a convex surface and a concave surface. The concave surface faces the inner cavity of the vapor deposition machine and is the side to be plated with aluminum metal. A perforated plating area 11 is provided on the surface of the planetary disk 1. Stepped grooves 112 are formed on the sidewalls of the plating area 11. The stepped grooves 112 are shallow, and the wafer has a certain degree of flexibility to be held within them, with the wafer's front facing the inner cavity of the vapor deposition machine. The plating area 11 is divided into a first holding area 1121 and a second holding area 1122 by the stepped grooves 112, from the concave surface of the planetary disk 1 towards the convex surface. A first cover plate 2 is engaged with the first holding area 1121, and a second cover plate 3 is engaged with the second holding area 1122.

[0040] The first cover plate 2 has a pre-reserved aluminum plating area 21, which is a hollow structure. The hollow pattern is designed and engraved according to the actual working conditions. When performing front-side aluminum plating, aluminum metal is plated on the wafer surface corresponding to the hollow pattern, and the wafer area covered by the first cover plate 2 will not be plated with aluminum metal.

[0041] Combination Figure 6 As shown, the first cover plate 2 is a circular sheet structure with an annular groove 22 on its curved surface. The annular groove 22 surrounds the curved surface, and a magnetic ring 221 is embedded in the annular groove 22. The volume of the magnetic ring 221 is approximately the same as the volume of the annular groove 22 (with a connection gap). Two magnetic blocks 111 are embedded in the first snap-fit ​​area 1121, arranged around the first snap-fit ​​area 1121. When the first cover plate 2 is snapped into the first snap-fit ​​area 1121, the magnetic ring 221 attracts the magnetic blocks 111, fixing the first cover plate 2 in place. Since the first cover plate 2 is located on the concave surface of the planetary disk 1, there is a risk of it falling off during aluminum plating. This design allows the first cover plate 2 to be adsorbed onto the planetary disk 1, thus better completing the aluminum plating operation.

[0042] A groove 23 is provided on the surface of the first cover plate 2. The groove 23 is located on the circular surface of the first cover plate 2 near the inner cavity of the vapor deposition machine, which facilitates the placement and removal of the first cover plate 2. The groove 23 is located at the edge of the first cover plate 2 and does not penetrate the first cover plate 2, so as not to affect the hollow pattern design of the aluminum plating area 21 on the surface of the first cover plate 2.

[0043] The second cover plate 3 is a circular sheet structure that covers the back of the wafer. During aluminum plating, the back of the wafer will not be plated with aluminum metal.

[0044] The second cover plate 3 is located on the raised surface of the planetary disk 1, and a protrusion 31 is fixed at the center of its surface to facilitate the removal and placement of the second cover plate 3.

[0045] Combination Figure 7As shown, a clamping mechanism 4 is provided on the planetary disk 1. The clamping mechanism 4 is located on the raised surface of the planetary disk 1 and includes a pressure plate 41 and a fixing part 42.

[0046] Combination Figure 8 As shown, the fixing part 42 includes a bolt 421, the bottom of which is fixedly connected to the planetary disk 1.

[0047] The pressure plate 41 is a strip-shaped structure with a broken cross-section, resembling a "W". One end of the pressure plate 41 has an opening and is fitted onto the bolt 421, rotatably connected to it. The other end of the pressure plate 41 includes an abutment portion 411, which is the lowest point of the broken cross-section and abuts against the surface of the second cover plate 3. When the second cover plate 3 needs to be removed or placed, the pressure plate 41 is rotated to one side. After the second cover plate 3 is engaged in the second engagement area 1122, the pressure plate 41 is rotated until the abutment portion 411 abuts against the second cover plate 3. This design of the pressure plate 41 effectively applies force to the surface of the second cover plate 3, thereby fixing the second cover plate 3 within the second engagement area 1122 and preventing it from falling off.

[0048] In summary, compared with existing technologies, it has the following beneficial effects:

[0049] This invention adds a first cover plate to the front of the wafer, and directly reserves a hollowed-out aluminum plating area on the first cover plate. When the planetary disk is placed in the evaporation machine for aluminum plating, aluminum metal can be plated on the wafer surface corresponding to the hollowed-out aluminum plating area. The area of ​​the first cover plate that is not hollowed out will cover the wafer and will not be plated with aluminum metal.

[0050] This invention eliminates the photoresist exposure, development, etching, and resist removal processes in traditional front-side aluminum plating. It directly improves the problem of poor aluminum plating in the wafer's aluminum plating area due to the splashing of developer and resist remover during the photoresist process, thus affecting wafer quality. The yield rate of the produced wafers is significantly improved, and the quality is guaranteed. This invention saves process steps, simplifies operation, reduces production processes, and significantly lowers production costs.

[0051] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0052] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A positive aluminum back silver wafer surface evaporation device, characterized in that, The device includes a planetary disk and a first cover plate. The planetary disk has a plating area, and the wafer is placed in the plating area. The first cover plate covers the front of the wafer and is located on the side of the planetary disk facing the inner cavity of the vapor deposition machine. The surface of the first cover plate has an aluminum plating area, which is configured as a hollow structure.

2. The apparatus for evaporating a surface of a positive aluminum back silver wafer as claimed in claim 1, wherein, The first cover plate is a circular sheet structure with an annular groove on its curved surface. A magnetic ring is embedded in the annular groove, and a magnetic block is embedded in the side wall of the area to be plated. The magnetic block and the magnetic ring attract each other.

3. The apparatus for evaporating a surface of a positive aluminum back silver wafer as claimed in claim 1, wherein, The first cover plate has a groove on its surface, and the groove is located at the edge of the first cover plate.

4. The apparatus for evaporating a surface of a positive aluminum back silver wafer as set forth in claim 1, wherein, A stepped groove is formed on the side wall of the area to be plated. The wafer is placed in the stepped groove. The stepped groove divides the area to be plated into a first snap-fit ​​area and a second snap-fit ​​area in sequence from the first cover plate toward the wafer. The first cover plate snaps into the first snap-fit ​​area.

5. The vapor deposition apparatus for the surface of a positive aluminum back silver wafer as described in claim 4, characterized in that, It also includes a second cover plate, which is snapped into the second snap-fit ​​area.

6. The apparatus for evaporating a surface of a positive aluminum back silver wafer as set forth in claim 5, wherein The second cover plate has a protrusion at the center for easy handling.

7. The apparatus for evaporating a surface of a positive aluminum back silver wafer as claimed in claim 5, wherein The planetary disk is provided with a pressing mechanism, which includes a pressing plate and a fixing part connected to the planetary disk. One end of the pressing plate is rotatably connected to the fixing part, and the other end of the pressing plate presses against the surface of the second cover plate.

8. The apparatus for evaporating a surface of a positive aluminum back silver wafer as claimed in claim 7, wherein, The cross-section of the pressure plate is a broken line shape, and the end away from the fixing part includes an abutting part, which is the lowest end of the pressure plate and abuts against the surface of the second cover plate.

9. The apparatus for evaporating a surface of a positive aluminum back silver wafer as claimed in claim 7, wherein, The fixing part includes a bolt that is rotatably fixed on the planetary disk, and the end of the pressure plate is fitted with a hole on the bolt and rotatably connected to the bolt.

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