Wafer electroplating apparatus

Abstract

The wafer electroplating equipment provided by the application comprises an electroplating tank for containing electroplating solution, an electroplating chamber composed of a cathode chamber, an anode chamber and an ion membrane between the cathode chamber and the anode chamber, a pipeline for connecting the electroplating tank and the electroplating chamber, and a pump body for providing power for the flow of the electroplating solution. Based on the above scheme and because the cathode chamber and the anode chamber share the same electroplating solution, only one pump body is used to provide power for the flow of the electroplating solution in the cathode chamber and the anode chamber, and the pump body and a flow regulator are used to replace the anode pump to pump the electroplating solution to the anode chamber, so that the flow of the anode chamber can meet the electroplating requirements, and the phenomenon of the anode pump being stuck due to the deposition of metal ions is avoided, thereby improving the wafer electroplating efficiency, and because the anode pump and the auxiliary pipeline are cancelled, the production, installation and maintenance costs are reduced.

Description

Technical Field

[0001] This invention belongs to the field of wafer electroplating technology, and in particular relates to a wafer electroplating device. Background Technology

[0002] A wafer is a silicon wafer used to fabricate silicon semiconductor circuits. High-purity polycrystalline silicon is dissolved and doped with silicon seed crystals to form cylindrical single-crystal silicon. After grinding, polishing, and slicing, the silicon ingot is formed into a silicon wafer. Further, a conductive metal layer is electroplated onto the wafer surface using the principle of electrolysis, and the conductive metal layer is processed to create conductive circuits.

[0003] Taking gold plating on wafers as an example, the wafer electroplating equipment generally includes a cathode plating chamber and an anode plating chamber, as well as an electroplating tank connected to the cathode plating chamber and the anode plating chamber. During electroplating, the electroplating solution in the electroplating tank fills the cathode plating chamber and the anode plating chamber under the action of the cathode pump and the anode pump. After electroplating, the electroplating solution in the cathode plating chamber and the anode plating chamber will flow back into the electroplating tank, thus forming a wafer electroplating circulation system.

[0004] However, in actual electroplating processes, the flow rate through the cathode pump is much greater than that through the anode pump. For example, in actual processes, the flow rate of the cathode pump is 15 LPM, while the flow rate of the anode pump is 1 LPM. This results in the anode pump being selected at a much smaller size than the cathode pump in practical applications. When the anode pump starts working, the gold in the electroplating solution, existing in complex form, is decomposed into free Au. + And free Au + The electron-gathering reaction is more likely to occur, and because the anode pump is smaller, the deposited gold will adhere to the anode pump, thereby jamming the anode pump and disrupting the wafer electroplating process.

[0005] Therefore, it is necessary to provide a wafer electroplating device to solve the above problems. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a wafer electroplating equipment to solve the problems of complex pipeline design and easy jamming of anode pumps in the prior art, which would damage the wafer electroplating process.

[0007] To achieve the above and other related objectives, the present invention provides a wafer electroplating apparatus, comprising:

[0008] An electroplating chamber, the electroplating chamber comprising a cathode chamber and an anode chamber, and an ion-exchange membrane located between the cathode chamber and the anode chamber;

[0009] An electroplating tank is used to hold an electroplating solution, and the electroplating tank is connected to the cathode chamber and the anode chamber respectively.

[0010] The pump body has an inlet end connected to the electroplating tank, and a first control valve is provided between the inlet end and the electroplating tank. The outlet end of the pump body is connected to the cathode chamber and the anode chamber respectively, and a second control valve is provided between the outlet end of the pump body and the cathode chamber. A flow regulator is provided between the outlet end of the pump body and the anode chamber.

[0011] Optionally, a third control valve is provided between the electroplating tank and the cathode chamber, and a fourth control valve is provided between the electroplating tank and the anode chamber. The third control valve and the fourth control valve are used to control the flow of electroplating solution from the electroplating chamber to the electroplating tank.

[0012] Optionally, the flow regulator includes an IP conversion controller that controls the flow rate in the anode chamber.

[0013] Optionally, a first flow meter is also provided between the flow regulator and the anode chamber.

[0014] Optionally, a debubbler is also provided between the second control valve and the cathode chamber.

[0015] Optionally, a filter for filtering insoluble impurities in the electroplating solution is also provided between the outlet end of the pump body and the cathode chamber.

[0016] Optionally, a second flow meter is also provided between the outlet end of the pump body and the cathode chamber, and the second flow meter is adjacent to the cathode chamber.

[0017] Optionally, the pump body has a specification of at least 15 LPM.

[0018] As described above, the wafer electroplating equipment of the present invention has the following beneficial effects: When the cathode chamber and the anode chamber share the same plating solution, the anode pump is eliminated, and a flow regulator is used to adjust the flow rate of the plating solution to the anode chamber. This achieves the effect of using a single pump to simultaneously provide power for the flow of plating solution to both the cathode and anode chambers. In this way, the required flow rate of plating solution to the anode chamber is met, while avoiding the anode pump jamming due to the easy deposition of metal ions. This improves wafer electroplating efficiency, and by eliminating the anode pump and a series of auxiliary pipelines, production costs, installation, and maintenance costs are reduced. Attached Figure Description

[0019] Figure 1The diagram shown is a schematic representation of the wafer electroplating equipment provided in an embodiment of the present invention.

[0020] Figure 2 The diagram shown is a structural schematic of the electroplating chamber in the wafer electroplating equipment of the present invention.

[0021] Component designation explanation

[0022] 101 Electroplating Tank

[0023] 102 Electroplating Chamber

[0024] 103 Cathode Chamber

[0025] 104 Anode Chamber

[0026] 105 ion exchange membrane

[0027] 106 Pump body

[0028] 1061 Entry Point

[0029] 1062 Export end

[0030] 107 First control valve

[0031] 108 Second control valve

[0032] 109 Flow Regulator

[0033] 110 Third control valve

[0034] 111 Fourth control valve

[0035] 112 First Flow Meter

[0036] 113 Filter

[0037] 114 Bubble Degasser

[0038] 115 Second Flow Meter

[0039] 116 First Liquid Supply Line

[0040] 117 Second Liquid Supply Line

[0041] 118 Third liquid supply line

[0042] 119 First return pipeline

[0043] 120 Second return line Detailed Implementation

[0044] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0045] In the detailed description of embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged and not to scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0046] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0047] It should be understood that the use of terms such as "first" and "second" to define the components is merely for the purpose of distinguishing the aforementioned components. Unless otherwise stated, these terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0048] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0049] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0050] like Figure 1 and Figure 2As shown, the present invention provides a wafer electroplating apparatus, which includes an electroplating chamber 102, an electroplating tank 101, and a pump body 106. The electroplating chamber 102 includes a cathode chamber 103 and an anode chamber 104, and an ion exchange membrane 105 located between the cathode chamber 103 and the anode chamber 104. The ion exchange membrane 105 is used to block the aqueous solution and allow cations to flow from the anode chamber to the cathode chamber.

[0051] The electroplating tank 101 is used to hold the electroplating solution, and the electroplating tank 101 is connected to the cathode chamber 103 and the anode chamber 104 respectively.

[0052] The inlet end 1061 of the pump body 106 is connected to the electroplating tank 101, and a first control valve 107 is provided between the inlet end 1061 and the electroplating tank 101. The outlet end 1062 of the pump body 106 is connected to the cathode chamber 103 and the anode chamber 104 respectively, and a second control valve 108 is provided between the outlet end 1062 of the pump body 106 and the cathode chamber 103. A flow regulator 109 is provided between the outlet end 1062 of the pump body 106 and the anode chamber 104.

[0053] Based on the above design, the wafer electroplating equipment allows the electroplating solution in the electroplating tank 101 to flow out from the same outlet and enter the inlet 1061 of the pump body 106. Pumped by the pump body 106, the solution is then transported from the outlet 1062 to the anode chamber 104 and the cathode chamber 103 respectively. During the electroplating process, the electroplating solution flows back from the cathode chamber 103 and the anode chamber 104 to the electroplating tank 101, achieving recycling of the electroplating solution between the cathode chamber 103, the anode chamber 104, and the electroplating tank 101. In existing electroplating processes, the flow rate of the electroplating solution required for the anode chamber 104 is relatively small, resulting in a smaller anode pump. Metals in the electroplating solution in complex form are easily deposited. For example, when performing gold plating, if the selected electroplating solution is potassium gold cyanide solution, the gold in the electroplating solution in complex form will be decomposed into free Au. + And free Au +The electro-electrode reaction easily occurs, and the deposited gold adheres to the pump head of the anode pump. However, smaller anode pumps have limited space at the pump head, making them prone to jamming if gold deposits there, preventing normal operation. Therefore, in the pipeline flowing from the electroplating tank 101 to the anode chamber 104, the anode pump is eliminated. Instead, the pump body 106, originally supplying the electroplating solution to the cathode chamber 103, provides pumping power to both the cathode and anode chambers 104. During the process, a flow regulator 109 adjusts the flow rate to the anode chamber 104, thus preventing anode pump jamming. Because the cathode chamber 103 requires a large flow rate of electroplating solution, in the actual process, the pump body 106 selected to supply the electroplating solution to the cathode chamber 103 is of a large size, and the space at the pump head is also large enough. The precipitation of metal will not cause the pump head to jam, thus ensuring the normal progress of the electroplating process and improving the wafer electroplating efficiency. Furthermore, with the elimination of the anode pump, the auxiliary pipelines that are integrated with the anode pump are also eliminated, thereby reducing production costs to a certain extent.

[0054] The structural design of the present invention will be described in detail below with reference to specific embodiments.

[0055] In this embodiment, as Figure 1 The diagram shows a schematic of a wafer electroplating equipment. The electroplating tank 101 is interconnected with the cathode chamber 103 and the anode chamber 104. The cathode chamber 103 and the anode chamber 104 are separated by an ion exchange membrane 105. The ion exchange membrane 105 can prevent the passage of aqueous solutions and additives in the electroplating solution, while allowing metal ions in the anode chamber 104 to pass through, thereby completing the electroplating of the wafer in the cathode chamber 103. In this embodiment, the wafer electroplating equipment also includes a pump body 106. The inlet end 1061 of the pump body 106 is connected to the electroplating tank 101 via a third liquid supply line 118. The outlet end 1062 of the pump body 106 is connected to the cathode chamber 103 via a first liquid supply line 116, and the outlet end 1062 of the pump body 106 is connected to the anode chamber 104 via a second liquid supply line 117. The power provided by the pump body 106 transports the electroplating solution in the electroplating tank 101 to the cathode chamber 103 and the anode chamber 104 respectively through the first liquid supply line 116 and the second liquid supply line 117, thereby supplying electroplating solution to the electroplating chamber 102. A first return line 119 is provided between the cathode chamber 103 and the electroplating tank 101, and a second return line 120 is provided between the anode chamber 104 and the electroplating tank 101. The entire system of the wafer electroplating equipment is connected by the first liquid supply line 116, the second liquid supply line 117, the third liquid supply line 118, the first liquid return line 119, and the second liquid return line 120, thereby enabling the recycling of electroplating solution between the cathode chamber 103 and the anode chamber 104 and the electroplating tank 101.

[0056] As an example, the cathode chamber 103 opens from the top and forms a channel for the wafer clamping assembly to enter and exit.

[0057] Specifically, such as Figure 1 and Figure 2 As shown, the wafer clamping assembly (not shown) is positioned directly above the cathode chamber 103. The top of the cathode chamber 103 is open to facilitate the smooth entry of the wafer into the cathode chamber 103 to complete the wafer electroplating process.

[0058] As an example, a third control valve 110 is provided between the electroplating tank 101 and the cathode chamber 103, and a fourth control valve 111 is provided between the electroplating tank 101 and the anode chamber 104. The third control valve 110 and the fourth control valve 111 are used to control the flow of electroplating solution from the electroplating chamber 102 to the electroplating tank 101.

[0059] Furthermore, the third control valve 110 can be installed in a position that suits the needs of the actual process. In this embodiment, the third control valve 110 is installed on the first return line 119. The fourth control valve 111 can be installed in a position that suits the needs of the actual process. In this embodiment, the fourth control valve 111 is installed on the second return line 120.

[0060] Specifically, such as Figure 1As shown, a first control valve 107 is provided on the third liquid supply pipeline 118 connecting the inlet end 1061 of the pump body 106 and the electroplating tank 101. The first control valve 107 can be selected according to actual process requirements. For example, in this embodiment of the invention, the first control valve 107 is a manual valve. By controlling the opening and closing of the third liquid supply pipeline 118 and adjusting the flow rate of the electroplating solution through the first control valve 107, the total flow rate of the electroplating solution flowing out of the electroplating tank 101 can be controlled. Then, under the power of the pump body 106, the electroplating solution is transported to the cathode chamber 103 and the anode chamber 104 through the first liquid supply pipeline 116 and the second liquid supply pipeline 117, respectively. Because the electroplating solution in the cathode chamber 103 and anode chamber 104 needs to reach a certain amount before the wafer electroplating process can be carried out, and a first return line 119 is provided between the cathode chamber 103 and the electroplating tank 101, and a second return line 120 is provided between the anode chamber 104 and the electroplating tank 101, in order to prevent the electroplating solution pumped into the anode chamber 104 and cathode chamber 103 from immediately flowing back into the electroplating tank 101, thus failing to meet the amount of electroplating solution required for the electroplating process, a third control valve 110 is provided between the electroplating tank 101 and the cathode chamber 103. The third control valve 110 can be adjusted according to the actual process. The installation location needs to be selected. In this embodiment, the third control valve 110 is installed on the first return liquid pipeline 119; a fourth control valve 111 is installed between the electroplating tank 101 and the anode chamber 104. The installation location of the fourth control valve 111 can be selected according to the actual process requirements. In this embodiment, the fourth control valve 111 is installed on the second return liquid pipeline 120. Similarly, the types of control valves 110 and 111 can be selected according to the actual process requirements. For example, in this embodiment, both the third control valve 110 and the fourth control valve 111 are manual valves. By controlling the opening and closing of the first return liquid pipeline 119 through the third control valve 110 and the opening and closing of the second return liquid pipeline 120 through the fourth control valve 111, the electroplating solution can be controlled to flow back from the cathode chamber 103 and the anode chamber 104 to the electroplating tank 101, thereby realizing the recycling of the electroplating solution.

[0061] As an example, the flow regulator 109 includes an IP conversion controller that controls the flow rate of the anode chamber 104.

[0062] Specifically, such as Figure 1As shown, a flow regulator 109 is provided between the outlet end 1062 of the pump body 106 and the anode chamber 104. Optionally, the flow regulator 109 is an IP conversion controller, which controls the flow rate to the anode chamber 104. Furthermore, a first flow meter 112 is also provided between the IP conversion controller and the anode chamber 104 to digitize the flow rate to the anode chamber 104, so that the operator can adjust the opening and closing of the IP conversion controller appropriately based on the flow rate value displayed by the first flow meter 112. However, the type of flow regulator 109 is not limited to this and can be adapted as needed.

[0063] As an example, a debuffer 114 is also provided between the second control valve 108 and the cathode chamber 103.

[0064] Specifically, such as Figure 1 As shown, since the flow rate of electroplating solution required by the cathode chamber 103 is much larger than that required by the anode chamber 104, in the actual equipment design, the inner diameter of the first supply pipe 116 connecting the cathode chamber 103 is also larger than the inner diameter of the second supply pipe 117 connecting the anode chamber 104. Therefore, when the first control valve 107 is opened, the electroplating solution will preferentially flow to the cathode chamber 103 in large quantities through the first supply pipe 116. At this time, the flow of electroplating solution through the second supply pipe 117 to the anode chamber 104 is almost zero, and this situation will continue. The result is that the anode... The electroplating solution in chamber 104 is consistently insufficient to meet the requirements of the wafer electroplating process. Therefore, in order to ensure that the amount of electroplating solution in the anode chamber 104 is sufficient for the electroplating process, in the actual process, the electroplating solution needs to flow preferentially to the anode chamber 104. After the amount of electroplating solution required by the anode chamber 104 is reached, the electroplating solution then flows to the cathode chamber 103. In this embodiment of the invention, the above-mentioned desired effect is achieved by setting a second control valve 108 between the outlet end 1062 of the pump body 106 and the cathode chamber 103. In this embodiment, the second control valve 108 is set on the first liquid supply pipeline 116. At the beginning of supplying the electroplating solution to the electroplating chamber 102, the second control valve 108 is closed to block the electroplating solution flowing to the cathode chamber 103, so that the electroplating solution is first delivered to the anode chamber 104. After the amount of electroplating solution in the anode chamber 104 reaches the required amount for electroplating, the second control valve 108 is then opened to allow the electroplating solution to flow to the cathode chamber 103, ultimately achieving the required flow rate of electroplating solution.

[0065] Furthermore, during the wafer electroplating process, trapped gases easily form on the wafer surface. These gases form bubbles that adhere to the wafer surface, and if left untreated, they will interfere with the electroplating process, resulting in uneven plating on the wafer surface. Therefore, a bubble degasser 114 is also provided between the second control valve 108 and the cathode chamber 103. In this embodiment, the bubble degasser 114 is located on the first liquid supply line 116. This allows the electroplating solution to remove bubbles flowing into the cathode chamber 103 as it passes through the bubble degasser 114, thereby reducing the impact of bubbles on the wafer electroplating quality. A filter 113 for filtering insoluble impurities in the electroplating solution is also provided between the outlet end 1062 of the pump body 106 and the cathode chamber 103. In this embodiment, the filter 113 is provided on the first liquid supply line 116 and the filter 113 is provided on the side of the second control valve 108 near the pump body 106. The filter 113 can filter out insoluble impurities in the electroplating solution, thereby reducing the impact of impurities on wafer electroplating.

[0066] As an example, a second flow meter 115 is also provided between the outlet end 1062 of the pump body 106 and the cathode chamber 103, and the second flow meter 115 is located adjacent to the cathode chamber 103.

[0067] Specifically, such as Figure 1 As shown, a second flow meter 115 is also provided between the outlet end 1062 of the pump body 106 and the cathode chamber 103. In this embodiment, the second flow meter 115 is provided on the first liquid supply pipeline 116, and the second flow meter 115 is provided on the side of the second control valve 108 away from the pump body 106 and close to the cathode chamber 103. The second flow meter 115 can digitize the electroplating liquid flowing to the cathode chamber 103, so that the staff can adjust the flow rate to the cathode chamber 103 appropriately according to the value displayed by the second flow meter 115.

[0068] As an example, the pump body specifications are at least 15 LPM.

[0069] Specifically, in this embodiment, when performing the gold plating process, potassium gold cyanide solution is selected as the electroplating solution. Since the flow rate required by the cathode chamber 103 is much greater than that of the anode chamber 104, for example, the flow rate required by the cathode chamber 103 is 12 LPM, while the flow rate required by the anode chamber 104 is only 1.5 LPM. In order to simultaneously meet the flow rate requirements of the cathode chamber 103, the selected pump body is at least 15 LPM, thereby ensuring that the flow rate requirements of the cathode chamber 103 and the anode chamber 104 are met at the same time.

[0070] In summary, the wafer electroplating equipment of the present invention includes an electroplating tank holding an electroplating solution, an electroplating chamber consisting of a cathode chamber, an anode chamber, and an ion membrane located between the cathode chamber and the anode chamber, pipelines connecting the electroplating tank and the electroplating chamber, and a pump body providing power for the flow of the electroplating solution. In this application, since the cathode chamber and the anode chamber share the same electroplating solution, the anode pump is eliminated, and a flow regulator is used to adjust the flow rate of the electroplating solution to the anode chamber. This achieves the effect of simultaneously providing power for the flow of the electroplating solution to both the cathode chamber and the anode chamber using a single pump body. In this way, the required flow rate of the electroplating solution supplied to the anode chamber is met, while avoiding the anode pump jamming due to the easy deposition of metal ions, thereby improving wafer electroplating efficiency. Furthermore, by eliminating the anode pump and a series of auxiliary pipelines, production costs, installation, and maintenance costs are reduced. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has high industrial applicability.

[0071] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A wafer electroplating equipment, characterized in that, include: An electroplating chamber, the electroplating chamber comprising a cathode chamber and an anode chamber, and an ion-exchange membrane located between the cathode chamber and the anode chamber; An electroplating tank is used to hold an electroplating solution, and the electroplating tank is connected to the cathode chamber and the anode chamber respectively. The pump body has an inlet end connected to the electroplating tank, and a first control valve is provided between the inlet end and the electroplating tank. The outlet end of the pump body is connected to the cathode chamber and the anode chamber respectively, and a second control valve is provided between the outlet end of the pump body and the cathode chamber. A flow regulator is provided between the outlet end of the pump body and the anode chamber.

2. The wafer electroplating equipment according to claim 1, characterized in that: A third control valve is provided between the electroplating tank and the cathode chamber, and a fourth control valve is provided between the electroplating tank and the anode chamber. The third control valve and the fourth control valve are used to control the flow of electroplating solution from the electroplating chamber to the electroplating tank.

3. The wafer electroplating equipment according to claim 1, characterized in that: The flow regulator includes an IP conversion controller, which adjusts the flow rate to the anode chamber.

4. The wafer electroplating equipment according to claim 1, characterized in that: A first flow meter is also provided between the flow regulator and the anode chamber.

5. The wafer electroplating equipment according to claim 1, characterized in that: A debubbler is also provided between the second control valve and the cathode chamber.

6. The wafer electroplating equipment according to claim 1, characterized in that: A filter for filtering insoluble impurities in the electroplating solution is also provided between the outlet end of the pump body and the cathode chamber.

7. The wafer electroplating equipment according to claim 1, characterized in that: A second flow meter is also provided between the outlet end of the pump body and the cathode chamber, and the second flow meter is adjacent to the cathode chamber.

8. The wafer electroplating equipment according to claim 1, characterized in that: The pump body has a specification of at least 15 LPM.

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