CN219315132U

CN219315132U - Wafer electroplating equipment

Info

Publication number: CN219315132U
Application number: CN202320555371.0U
Authority: CN
Inventors: 顾中凯; 刘城军; 章云飞; 郑文
Original assignee: Shenghejing Micro Semiconductor Jiangyin Co Ltd
Current assignee: SJ Semiconductor Jiangyin Corp
Priority date: 2023-03-21
Filing date: 2023-03-21
Publication date: 2023-07-07
Anticipated expiration: 2033-03-21

Abstract

The utility model provides wafer electroplating equipment which comprises an electroplating bath, a chuck, a base and a plurality of guide posts, wherein the base is positioned between the chuck and a wafer to be plated, the guide posts are distributed on the same circumferential surface of the chuck at intervals and symmetrically, each guide post comprises a rigid guide section and an elastic guide section, one end of the rigid guide section is fixed with the chuck, one end of the elastic guide section is connected with one end of the rigid guide section, which is away from the chuck, and the other end of the elastic guide section extends downwards to the edge of the wafer to be plated so as to prop against the wafer. The wafer electroplating equipment provided by the application is provided with the elastic guide section, so that when the wafer is pressed downwards under the condition that the wafer is not completely centered due to the position deviation, the elastic guide section can provide buffering for the wafer, so that the wafer can be gradually restored to a horizontal state without hard collision with the wafer, the wafer can be effectively prevented from being damaged, and the electroplating yield is improved.

Description

Wafer electroplating equipment

Technical Field

The utility model relates to the technical field of semiconductor manufacturing, in particular to wafer electroplating equipment.

Background

Electroplating is a process of plating a thin layer of metal on the surface of an existing material layer by utilizing the electrolysis principle. Electroplating has the advantages of high coating efficiency, multiple coating types and the like, so that the electroplating is widely applied to the manufacturing process of semiconductor chips. For example, in back-end packaging, electroplating processes are often used to fabricate interconnect structures such as metal bumps.

In the electroplating process, the wafer is fixed by a clamping device, and the back surface of the wafer is covered by a pressing plate. The crystal compass grids commonly used in the market at present mainly comprise 200mm and 300 mm. In order to ensure that the wafer can be placed in the clamping device smoothly and safely, the distance between the diagonal guide posts of the clamping device is usually slightly larger than the wafer, for example, 200.2/300.2mm, so that the wafer has a movable space in the clamping device, which makes centering of the wafer difficult. Because the guide post in the existing electroplating equipment is a rigid and integrated structure, one end of the guide post is fixedly connected with the chuck, and the other end of the guide post is propped against the edge of the wafer to fix the wafer. If the wafer is not completely centered, when the back surface of the wafer is pressed downward, one side of the wafer is easily broken by hard collision with the guide posts, resulting in a decrease in the production yield.

It should be noted that the foregoing description of the background art is only for the purpose of facilitating a clear and complete description of the technical solutions of the present application and for the convenience of understanding by those skilled in the art. The above-described solutions are not considered to be known to the person skilled in the art simply because they are set forth in the background section of the present application.

Disclosure of Invention

In view of the above-mentioned drawbacks of the prior art, an object of the present utility model is to provide a wafer electroplating apparatus, which is used for solving the problems that in the prior art, the electroplating apparatus is rigid due to the guide post, and when the wafer is not completely centered and pressed, one side of the wafer is easy to collide with the guide post and break.

To achieve the above and other related objects, the present utility model provides a wafer plating apparatus, which includes a plating tank, a chuck, a base, and a plurality of guide posts, wherein the base is located between the chuck and a wafer to be plated, the plurality of guide posts are spaced and symmetrically distributed on the same circumferential surface of the chuck, each guide post includes a rigid guide section and an elastic guide section, one end of the rigid guide section is fixed with the chuck, one end of the elastic guide section is connected with one end of the rigid guide section, which is away from the chuck, and the other end extends downward to the edge of the wafer to be plated to prop against the wafer.

Optionally, the resilient guide section comprises a stainless steel sheet.

Optionally, the number of the guide posts is 4, the 4 guide posts are positioned on 4 vertex angles of a rectangular surface, and the center point of the rectangular surface coincides with the center point of the base.

Optionally, one end of the elastic guide section, which is away from the rigid guide section, is also provided with a horizontal extension section extending to the edge of the wafer coating surface.

Optionally, the elastic guide section and the rigid guide section are connected by threads.

Optionally, a threaded hole is formed in the chuck, and the rigid guide section is embedded into the threaded hole of the chuck to fix the chuck and the rigid guide section.

Optionally, the wafer electroplating device further comprises a rotating device connected with the base.

Optionally, the wafer electroplating device further comprises a lifting device connected with the base.

Optionally, the wafer electroplating apparatus further comprises a waste liquid collecting tank located outside the electroplating tank.

Optionally, the wafer electroplating device further comprises springs, the number of the springs is matched with that of the guide posts, and the springs are arranged on the outer sides of the elastic guide sections in a one-to-one correspondence mode and are abutted to the elastic guide sections.

As described above, the wafer electroplating equipment of the utility model has the following beneficial effects: the wafer electroplating equipment that this application provided is because of setting up the elastic guide section, under the circumstances that the wafer takes place the offset and not the centering completely, when pressing down the in-process of wafer, the elastic guide section can provide the buffering for the wafer can resume the horizontality gradually and can not take place hard collision with the wafer, can effectively avoid the wafer damage, improves electroplating yield.

Drawings

Fig. 1 is a schematic view illustrating an exemplary structure of a wafer plating apparatus according to the present utility model.

Detailed Description

Other advantages and effects of the present utility model will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present utility model with reference to specific examples. The utility model may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present utility model. As described in detail in the embodiments of the present utility model, the cross-sectional view of the device structure is not partially enlarged to a general scale for convenience of explanation, and the schematic drawings are only examples, which should not limit the scope of the present utility model. In addition, the three-dimensional dimensions of length, width and depth should be included in actual fabrication.

For ease of description, spatially relative terms such as "under", "below", "beneath", "above", "upper" and the like may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that these spatially relative terms are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the figures. Furthermore, when a layer is referred to as being "between" two layers, it can be the only layer between the two layers or one or more intervening layers may also be present.

In the context of this application, a structure described as a first feature being "on" a second feature may include embodiments where the first and second features are formed in direct contact, as well as embodiments where additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

It should be noted that, the illustrations provided in the present embodiment merely illustrate the basic concept of the present utility model by way of illustration, and only the components related to the present utility model are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complex. In order to make the illustration as concise as possible, not all structures are labeled in the drawings.

Please refer to fig. 1.

As shown in fig. 1, the present application provides a wafer plating apparatus, which includes a plating tank 11, a chuck 12, a base 13, and a plurality of guide posts 14. The base 13 is located between the chuck 12 and the wafer 18 to be plated, and the base 13 is connected to the chuck 12, for example, by fastening with screws or the like. The base 13 can fix the wafer 18 on the surface thereof by vacuum adsorption, so the base 13 can be correspondingly provided with a vacuum chuck 131 communicated with an air extractor such as a vacuum pump, and the vacuum chuck 131 can be provided with a horn-shaped opening to enlarge the contact area with the wafer 18 and enhance the adsorption effect. The chuck 12 is annular, and the plurality of guide posts 14 are spaced and symmetrically distributed on the same circumferential surface of the chuck 12, so that the guide posts 14 are generally an even number, for example, 4, 6 or other numbers, and preferably 4 in this embodiment, the 4 guide posts 14 are located at 4 top corners of the same rectangular surface, and the center point of the rectangular surface coincides with the center point of the base 13. Each guide column 14 comprises a rigid guide section 141 and an elastic guide section 142, one end of the rigid guide section 141 is fixed with the chuck 12, one end of the elastic guide section 142 is connected with one end of the rigid guide section 141 away from the chuck 12, and the other end extends downwards to the edge of the wafer to be plated to prop against the wafer 18. That is, one end of the elastic guide section 142 is connected to the rigid guide section 141 to be fixed, and the other end is a free end. Rigid guide section 141, as the name implies, is rigid, being made of a rigid material, without or substantially without elasticity. In contrast, the resilient guide segments 142 are less rigid than the rigid guide segments 141 and are relatively more resilient.

The exemplary working principle of the wafer electroplating apparatus of this embodiment is that before electroplating, the guide post 14, the base 13 and the chuck 12 are fixed, the wafer is turned over by the mechanical arm after the wafer is taken out from the wafer box, so that the film plating surface of the wafer faces downwards, after the wafer is moved to a preset position, the wafer 18 is horizontally placed between the base 13 and the guide post 14, and the circumferential edge of the wafer 18 abuts against the elastic guide post 14. Then, the wafer 18 is pressed down to level and center the wafer, and finally, the wafer 18 is moved to the plating tank 11 for plating. In this process, the robot arm may shift the position of the wafer 18 when it is placed in the guide posts 14, so that the wafer 18 is not in a completely horizontal alignment state, but is obliquely mounted on the elastic guide sections 142 of the guide posts 14 on the corresponding sides (but the inclination is generally not so serious that the wafer 18 is not separated from the guide posts 14). When the wafer 18 is pressed downward, the elastic guide section 142 is elastic, so that the wafer can be buffered and not be hard to touch (the hardness of the silicon wafer is relatively high), so that the wafer can be restored to the horizontal centering state, and the wafer is prevented from being damaged. Therefore, by adopting the wafer electroplating equipment provided by the application, the process tolerance can be improved, the breaking risk is reduced, and the electroplating yield is improved.

As an example, the rigid guide section 141 is vertically disposed and the elastic guide section 142 is inclined toward the center of the wafer. That is, the elastic guide sections 142 are disposed at an inclined angle to the horizontal so that the distance between the elastic guide sections 142 of the two guide posts 14 located on the diagonal is gradually reduced from top to bottom as shown in fig. 1, so that the distance between the two guide posts 14 is gradually reduced from the size initially set to be slightly larger than the wafer for easy placement of the wafer until the distance between the ends is smaller than the wafer size, thereby being capable of supporting the wafer to prevent the wafer from falling. The elasticity of the elastic guiding section 142 cannot be too great, otherwise, the elastic guiding section cannot be used for well supporting the wafer; nor too small, otherwise the wafer is easily damaged when it collides with the wafer. The choice of material for the resilient guide segment 142 is important. In a preferred example, the resilient guide segment 142 may be a stainless steel sheet. Stainless steel has hardness smaller than that of titanium alloy and other metals, but has better mechanical strength and is easy to recover after deformation. To better assist in supporting the wafer, the area of the resilient guide section 142 that abuts the wafer may have an arcuate surface that matches the edge of the wafer. The rigid guide section 141 may be made of a metal having a relatively high hardness such as titanium alloy.

In an example, the end of the elastic guiding section 142 facing away from the rigid guiding section 141 is further provided with a horizontal extending section 143 extending to the edge of the wafer coating surface. The horizontal extension 143, as the name implies, is horizontally disposed and has an extension length that does not exceed the size of the non-plating area of the plating surface of the wafer to be plated. The provision of the horizontal extension 143 can better support the wafer.

The resilient guide section 142 and the rigid guide section 141 may be connected by suitable means, such as fasteners, e.g. screws. In a preferred example, however, the resilient guide section 142 and the rigid guide section 141 are threadably connected. I.e. one of the surfaces of the elastic guide section 142 and the rigid guide section 141 is provided with an internal thread and the other surface is provided with an external thread, both of which are fastened when screwing one into the threaded hole of the other. The structure not only makes the installation and the disassembly very convenient, but also has no protruding point on the surface of the joint where the two guide sections are installed, so that even if the wafer touches the installation joint of the two guide sections, the joint is not scratched or damaged.

The arrangement of the chuck 12 and the guide post 14 can likewise take a variety of forms. In one example, the chuck 12 is provided with a threaded hole, and the rigid guide section 141 is embedded in the threaded hole of the chuck 12 to fix the chuck 12 and can be fastened by adding a nut. In other examples, a plurality of threaded holes may be provided in the chuck 12, and the guide posts 14 may be fixed in different threaded holes, so as to support wafers of different sizes, thereby improving the applicability of the wafer plating apparatus.

In an example, the wafer plating apparatus further comprises a rotating device 17, which is connected to the base 13, and the rotating device 17 comprises a rotating motor, for example. The rotating device is arranged and can drive the base 13 to rotate when needed, so that the wafer is driven to rotate, and the electroplating uniformity is improved. In addition, the wafer plating apparatus may further include a lifting device (not shown), for example, a cylinder, connected to the base 13 to drive the base 13 to lift when necessary, thereby changing the distance between the wafer and the anode 111, which may function to change the potential between the anode 111 and the cathode, and also may function to improve plating uniformity. The rotation means and the lifting means may alternatively be arranged, preferably simultaneously.

In other examples, a lifting device 19 may be provided at the bottom of the plating vessel 11 and connected to the plating vessel 11, and the lifting device 19 may be a cylinder, for example. Changing the distance between the wafer and the anode 111 by the lifting device 19 at the bottom of the plating tank 11 can also function to change the potential between the anode 111 and the cathode, thereby improving plating uniformity.

In an example, the wafer plating apparatus further includes a waste liquid collecting tank 16 disposed outside the plating tank 11, and a liquid outlet 161 may be disposed on the waste liquid collecting tank 161, and the liquid discharged from the plating tank 11 flows into the waste liquid collecting tank 16.

In an example, the wafer plating apparatus further includes springs 15, the number of which is matched with that of the guide posts 14, and the springs 15 are disposed on the outer sides of the elastic guide sections 142 in a one-to-one correspondence and are abutted against the elastic guide sections 142. The spring 15 may be secured by a support structure (not shown) coupled to the chuck 12. The spring 15 can provide supporting force for the elastic guide section 142, so that the elastic guide section 142 can be prevented from being incapable of effectively fixing the wafer due to faults, and the safety of equipment is improved.

The wafer plating apparatus may also be provided with a closed housing (not shown) in which all of the aforementioned structures, except for the driving means such as the lifting means and the rotating means, may be disposed. An air inlet and an air outlet can be arranged on the closed shell. Inert gas can be introduced into the closed shell through the gas inlet, so that the inert gas atmosphere is kept in the closed shell, the wafer pollution is prevented, and redundant gas is discharged through the gas outlet. In other examples, the plating process may also be performed in a vacuum environment by evacuating the containment vessel.

In summary, the present utility model provides a wafer electroplating apparatus. The wafer electroplating equipment comprises an electroplating bath, a chuck, a base and a plurality of guide posts, wherein the base is positioned between the chuck and a wafer to be plated, the guide posts are spaced on the same circumferential surface of the chuck and are symmetrically distributed, each guide post comprises a rigid guide section and an elastic guide section, one end of the rigid guide section is fixed with the chuck, one end of the elastic guide section is connected with one end of the rigid guide section, which is away from the chuck, and the other end of the elastic guide section is downwards extended to the edge of the wafer to be plated so as to prop against the wafer. The wafer electroplating equipment that this application provided is because of setting up the elastic guide section, under the circumstances that the wafer takes place the offset and not centering completely, when pressing down the in-process of wafer, the elastic guide section can provide the buffering for the wafer can resume the horizontal centering state gradually and can not take place hard collision with the wafer, can effectively avoid the wafer damage, improves electroplating yield. Therefore, the utility model effectively overcomes various defects in the prior art and has high industrial utilization value.

The above embodiments are merely illustrative of the principles of the present utility model and its effectiveness, and are not intended to limit the utility model. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the utility model. Accordingly, it is intended that all equivalent modifications and variations of the utility model be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims

1. The wafer electroplating equipment is characterized by comprising an electroplating tank, a chuck, a base and a plurality of guide posts, wherein the base is positioned between the chuck and a wafer to be plated, the guide posts are distributed on the same circumferential surface of the chuck at intervals and symmetrically, each guide post comprises a rigid guide section and an elastic guide section, one end of each rigid guide section is fixed with the chuck, one end of each elastic guide section is connected with one end of each rigid guide section, which is away from the chuck, and the other end of each elastic guide section extends downwards to the edge of the wafer to be plated so as to prop against the wafer.

2. The wafer plating apparatus as recited in claim 1, wherein said elastic guide section comprises a stainless steel sheet.

3. The wafer plating apparatus as recited in claim 1, wherein said guide posts are 4, and 4 guide posts are located at 4 top corners of a rectangular surface, a center point of said rectangular surface being coincident with a center point of said base.

4. The wafer plating apparatus as recited in claim 1, wherein an end of said elastic guide section facing away from said rigid guide section is further provided with a horizontally extending section extending to an edge of the wafer plating surface.

5. The wafer plating apparatus as recited in claim 1, wherein said elastic guide section and said rigid guide section are connected by threads.

6. Wafer plating apparatus according to claim 1, characterized in that the chuck is provided with threaded holes, and the rigid guide section is embedded in the threaded holes of the chuck for fixing both.

7. The wafer plating apparatus as recited in claim 1, further comprising a rotating device coupled to the base.

8. The wafer plating apparatus as recited in claim 7, further comprising a lifting device coupled to the base.

9. The wafer plating apparatus as recited in claim 1, further comprising a waste collection tank outside the plating tank.

10. The wafer plating apparatus according to any one of claims 1 to 9, further comprising springs, the number of which is matched with that of the guide posts, the springs being disposed one-to-one outside the elastic guide sections and abutting against the elastic guide sections.