Electroplating apparatus and electroplating method thereof

Abstract

This application provides an electroplating apparatus and method thereof. The electroplating apparatus includes an electroplating tank, an electroplating anode, a power supply module, and a conductive component. The electroplating tank holds an electroplating solution and a device to be electroplated. The device is electrically connected to the cathode of the power supply module. The electroplating anode is disposed in the electroplating tank and positioned opposite the device. The conductive component is electrically connected to the cathode of the power supply module and is at least partially disposed in the electroplating solution, adjacent to the edge of the device. The electroplating apparatus of this application can improve the uniformity of electroplating and avoid problems such as under-plating or missed plating of the device.

Description

Technical Field

[0001] This application relates to the field of electroplating technology, specifically to an electroplating apparatus and an electroplating method thereof. Background Technology

[0002] Integrated circuit manufacturing is a planar fabrication process that includes various steps such as material deposition, patterning, doping, chemical mechanical polishing, spot polishing, and heat treatment. It involves forming various types of complex devices on a single substrate and interconnecting them to achieve complete electrical functions. Among these processes, metal deposition and the formation of metal wiring both require electroplating, i.e., material deposition. However, the thickness of the electroplated layer formed by using existing electroplating equipment is uneven; the uniformity of the electroplated layer does not meet the process requirements, which may make it impossible to carry out other subsequent processes (such as chemical mechanical polishing and etching processes), or even cause the electroplated workpiece to be scrapped, which not only reduces product quality, but also increases manufacturing costs. Summary of the Invention

[0003] The purpose of this application is to provide an electroplating apparatus that can improve the uniformity of electroplating and avoid problems such as under-plating or missed plating of components.

[0004] To address the aforementioned technical problems, this application provides an electroplating apparatus, comprising an electroplating tank, an electroplating anode, a power supply module, and a conductive component. The electroplating tank is used to hold an electroplating solution and a device to be electroplated. The device is electrically connected to the cathode of the power supply module. The electroplating anode is disposed in the electroplating tank and is disposed opposite to the device. The conductive component is electrically connected to the cathode of the power supply module. The conductive component is at least partially disposed in the electroplating solution and is disposed adjacent to the edge of the device.

[0005] Optionally, the conductive element includes a current access point electrically connected to the power module, and the width of the conductive element gradually increases in the direction away from the current access point.

[0006] Optionally, the conductive element is ring-shaped and is arranged circumferentially around the device.

[0007] Optionally, the electroplating apparatus further includes a carrier on which at least one of the devices is fixed. The carrier is provided with a line electrically connected to the device. The carrier is electrically connected to the power module through the line. The conductive element is disposed on the carrier and electrically connected to the line.

[0008] Optionally, the carrier has a plurality of the devices arranged in a matrix, the circuit is disposed between two adjacent devices, and the conductive element is disposed on the outer edge of each device away from the circuit.

[0009] Optionally, the conductive element includes a first conductive strip, a second conductive strip, a third conductive strip, and a fourth conductive strip connected end to end. A plurality of the devices are located within the area enclosed by the first conductive strip, the second conductive strip, the third conductive strip, and the fourth conductive strip. The first conductive strip is electrically connected to the circuit and is located outside the electroplating solution. The second conductive strip and the fourth conductive strip are at least partially disposed in the electroplating solution, and the third conductive strip is located in the electroplating solution.

[0010] Optionally, the conductive element further includes a fifth conductive strip, which is connected between the second conductive strip and the fourth conductive strip, and the fifth conductive strip is located between two adjacent devices.

[0011] This application also relates to an electroplating method using the above-described electroplating apparatus, the electroplating method comprising: The device to be electroplated and the conductive component are electrically connected to the cathode of the power module, and the electroplating anode is electrically connected to the anode of the power module. The device, the electroplating anode, and at least a portion of the conductive elements are disposed in the electroplating solution, with the conductive elements disposed adjacent to the device. When the power module is working, the conductive element can disperse the electric field lines at the edge of the device.

[0012] Optionally, the conductive element is arranged circumferentially around the device; when the power module is working, the conductive element can disperse the electric field lines around the device.

[0013] Optionally, at least one of the devices is fixed to a carrier and electrically connected to a circuit on the carrier, with the conductive element positioned away from the circuit.

[0014] The conductive component of the electroplating apparatus of this application is located at the edge of the device. When the device is energized, the current density is highest at the sharp points such as edges, corners, and edges, resulting in the most electric field lines. This application uses an external conductive component to dedicate the electric field lines in the high current density areas of the device as a dedicated tip discharge area, which can reduce the tip discharge effect at the edge of the device. This makes the conductive component a sacrificial element for electroplating, solving the problem of excessive concentration of electric field lines. This ensures that the plating thickness at the edge of the device will not be greater than the plating thickness in the middle of the device, thereby improving the uniformity of electroplating and effectively avoiding problems such as under-plating or missed plating. Moreover, the electroplating apparatus of this application is simple, does not require complex components, and has low manufacturing cost.

[0015] The above description is merely an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without any creative effort.

[0017] Figure 1 This is a schematic diagram of the electroplating apparatus of this application; Figure 2 This is a top view of the conductive component of this application. Figure 3 This is a top view schematic diagram of the conductive elements and devices disposed on a carrier according to an embodiment of this application; Figure 4 This is a top view schematic diagram of the conductive elements and devices disposed on a carrier according to another embodiment of this application; Figure 5 This is a schematic diagram showing the device of this application divided into 25 squares.

[0018] The realization of the objectives, functional features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and textual descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concepts of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0019] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification.

[0020] In the following description, reference is made to the accompanying drawings, which illustrate several embodiments of the present application. It should be understood that other embodiments may also be used, and changes in mechanical composition, structure, electrical and operational aspects may be made without departing from the spirit and scope of the present application. The following detailed description should not be considered limiting, and the terminology used herein is for describing particular embodiments only and is not intended to limit the present application.

[0021] Although the terms first, second, etc., are used in some instances to describe various elements herein, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

[0022] Furthermore, as used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context indicates otherwise. It should be further understood that the terms “comprising,” “including,” indicate the presence of a feature, step, operation, element, component, item, kind, and / or group, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms “or” and “and / or” as used herein are interpreted as inclusive, or mean any one or any combination thereof. Thus, “A, B, or C” or “A, B, and / or C” means “any one of: A; B; C; A and B; A and C; B and C; A, B, and C.” Exceptions to this definition arise only when combinations of elements, functions, steps, or operations are inherently mutually exclusive in some way.

[0023] Figure 1 This is a schematic diagram of the electroplating apparatus of this application, as shown below. Figure 1 As shown, the electroplating apparatus includes an electroplating tank 12, an electroplating anode 13, a power supply module 14, and a conductive element 15. The electroplating tank 12 is used to hold the electroplating solution and the device 21 to be electroplated. The device 21 is electrically connected to the cathode of the power supply module 14. The electroplating anode 13 is disposed in the electroplating tank 12 and is disposed opposite to the device 21. The conductive element 15 is electrically connected to the cathode of the power supply module 14. The conductive element 15 is at least partially disposed in the electroplating solution and is disposed adjacent to the edge of the device 21.

[0024] When the electroplating apparatus performs electroplating operation on the device 21, an electroplating electric field is formed between the device 21 and the electroplating anode 13. Since the conductive element 15 is located at the edge of the device 21, the high-density electric field lines at the edge of the device 21 are led to the conductive element 15.

[0025] The conductive element 15 of the electroplating apparatus of this application is disposed at the edge of the device 21. When the device 21 is energized, the current density is highest at the sharp points such as the edges, corners, and edges of the device 21, resulting in the most electric field lines at these locations. This application uses the external conductive element 15 as a dedicated sharp discharge area for the electric field lines in the high current density area of ​​the device 21, which can reduce the sharp discharge effect at the edge of the device 21. This makes the conductive element 15 a sacrificial element for electroplating, solving the problem of excessive concentration of electric field lines. This ensures that the plating thickness at the edge of the device 21 will not be greater than the plating thickness in the middle of the device 21, thereby improving the uniformity of electroplating and effectively avoiding problems such as under-plating or missed plating of the device 21. Moreover, the electroplating apparatus of this application is simple, does not require complex components, and has low manufacturing cost.

[0026] Optionally, Figure 2 This is a top view of the conductive component of this application, as shown in the diagram. Figure 2 As shown, the conductive element 15 includes a current access point 101 electrically connected to the power module 14. The width of the conductive element 15 gradually increases in the direction away from the current access point 101. In this embodiment, the current density of the conductive element 15 is lower closer to the current access point 101 and higher further away from the current access point 101. Therefore, this application makes corresponding adjustments to the width of the conductive element 15. A wider area can disperse more electric field lines, and this design can make the plating thickness more uniform.

[0027] Optionally, the material of the conductive element 15 depends on the type of electroplating metal. For example, if the device 21 to be electroplated is a semiconductor wafer, the electroplating material is copper.

[0028] Optionally, such as Figure 1 and Figure 2 As shown, the conductive element 15 is in the shape of a ring and is arranged around the circumference of the device 21.

[0029] In other embodiments, the conductive element 15 can be a straight strip, an L-shape, a polygon, etc., depending on the arrangement of the device 21, and is not limited to the above.

[0030] Optionally, Figure 3 This is a top view schematic diagram of the conductive elements and devices disposed on a carrier according to an embodiment of this application, as shown. Figure 3 As shown, the electroplating apparatus also includes a carrier 16, on which at least one device 21 is fixed. The carrier 16 is provided with a line 161 that electrically connects to the device 21. The carrier 16 is electrically connected to the power module 14 through the line 161. A conductive element 15 is disposed on the carrier 16 and electrically connected to the line 161.

[0031] Optionally, a plurality of devices 21 arranged in a matrix are fixed on the carrier 16, with lines 161 disposed between two adjacent devices 21, and conductive elements 15 disposed on the outer edge of each device 21 away from the lines 161. In this embodiment, four devices 21 are fixed on the carrier 16, and the lines 161 pass between the plurality of devices 21 and are electrically connected to each device 21 respectively.

[0032] Optionally, the conductive element 15 includes a first conductive strip 151, a second conductive strip 152, a third conductive strip 153, and a fourth conductive strip 154 ​​connected end to end. Multiple devices 21 are located within the area enclosed by the first conductive strip 151, the second conductive strip 152, the third conductive strip 153, and the fourth conductive strip 154. The first conductive strip 151 is electrically connected to the line 161 and is located outside the electroplating solution. The second conductive strip 152 and the fourth conductive strip 154 ​​are at least partially disposed in the electroplating solution, and the third conductive strip 153 is also located in the electroplating solution. In this embodiment, the current introduction point 101 of the line 161 is close to the first conductive strip 151. Therefore, the electric field line density at the upper edges of the two devices 21 near the first conductive strip 151 is not high, and the first conductive strip 151 does not need to disperse the electric field lines. Therefore, the first conductive strip 151 of this application is disposed outside the electroplating solution.

[0033] Optionally, the first conductive strip 151, the second conductive strip 152, the third conductive strip 153 and the fourth conductive strip 154 ​​form a rectangular area, and the second conductive strip 152, the third conductive strip 153 and the fourth conductive strip 154 ​​can disperse the electric field lines at the edges of each device 21.

[0034] Optionally, Figure 4 This is a top view schematic diagram of the conductive elements and devices disposed on a carrier according to another embodiment of this application, as shown below. Figure 4 As shown, the conductive element 15 also includes a fifth conductive strip 155, which is connected between the second conductive strip 152 and the fourth conductive strip 154, and is located between two adjacent devices 21. The fifth conductive strip 155 of this application passes between two adjacent devices 21, which can improve the plating thickness at the edges of the two adjacent devices 21.

[0035] This application also relates to an electroplating method using the above-described electroplating apparatus, the electroplating method comprising: The device 21 to be electroplated and the conductive part 15 are electrically connected to the cathode of the power module 14, and the electroplating anode 13 is electrically connected to the anode of the power module 14. The device 21, the electroplating anode 13 and at least a portion of the conductive element 15 are disposed in the electroplating solution, and the conductive element 15 is disposed adjacent to the device 21. When the power module 14 is working, the conductive element 15 can disperse the electric field lines at the edge of the device 21.

[0036] Optionally, the conductive element 15 is arranged around the circumference of the device 21; when the power module 14 is working, the conductive element 15 can disperse the electric field lines around the device 21.

[0037] Optionally, at least one device 21 is fixed on the carrier 16 and electrically connected to the line 161 on the carrier 16, and the conductive element 15 is positioned away from the line 161.

[0038] To verify the effectiveness of the electroplating apparatus of this application in improving the uniformity of the plating layer, a vertical electroplating machine in the laboratory was selected, and four devices 21 were fixed on the carrier 16. The specific experiment is as follows: Prepare three carriers 16, each with four devices 21 to be electroplated fixed on it. Each device 21 measures 10cm × 10cm. The four devices 21 are designated as L1 (top left), L2 (bottom left), R1 (top right), and R2 (bottom right). Current is introduced from the top of the line 161. The width of each conductive strip of the conductive element 15 is 1cm. The carrier 16 without conductive elements 15 is used as Experimental Scheme 1, serving as the reference group for subsequent data. The carrier 16 with conductive elements 15... Figure 3 The carrier 16 of the conductive element 15 shown is used as experimental scheme 2; the carrier 16 with the conductive element 15 is used as experimental scheme 2; Figure 4 The carrier 16 of the conductive component 15 shown is used as experimental scheme 3; the electroplating current is uniformly 6.5A, the electroplating time is different, and the electroplating rate of the corresponding point is calculated according to the electroplating measurement point. Then, based on the target thickness, it is multiplied by the corresponding electroplating time to compare the uniformity.

[0039] Table 1 Electroplating parameters

[0040] Figure 5 This is a schematic diagram of the device in this application divided into 25 squares, as shown below. Figure 5 As shown, each device 21 is divided into small squares of 2cm × 2cm, and each device 21 has a total of 25 data points.

[0041] As shown in Table 2, the average plating rate only reflects the average level to a certain extent and does not reflect the plating rate at each individual point. Therefore, it is necessary to calculate the plating rate of each square before performing other analyses.

[0042] Table 2 Experimental Results

[0043] Table 3 Electroplating rates for each cell in Scheme 1

[0044] Table 4 Electroplating rates of each grid cell in Scheme 2

[0045] Table 5 Electroplating Rate of Each Grid in Scheme 3

[0046] Experimental Analysis 1. Comparison of current density distribution A colorimetric analysis was performed on the electroplating rate at each grid measurement point of the three schemes (the magnitude of the electroplating rate reflects the magnitude of the current density in that area, or the density of the charge quantity, or the density of electric field lines). It can be seen that the current density distribution of scheme 1 has the largest difference, while the current density distribution of schemes 2 and 3 has the smallest difference.

[0047] 2. Thickness uniformity Based on the electroplating rate of each square, multiply by the corresponding electroplating time, and then calculate the average value. With the target thickness of 5µm as a reference, perform a colorimetric analysis on the test points of each scheme, and then calculate the thickness uniformity of each scheme.

[0048] Table 6 Experimental Results

[0049] The above experiments demonstrate that the electroplating apparatus and electroplating method of this application can improve the uniformity of electroplating.

[0050] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Furthermore, the structures or structural features involved can be arbitrarily combined and superimposed. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. An electroplating apparatus, characterized in that, The device includes an electroplating tank, an electroplating anode, a power module, and a conductive component. The electroplating tank is used to hold the electroplating solution and the device to be electroplated. The device is electrically connected to the cathode of the power module. The electroplating anode is disposed in the electroplating tank and is disposed opposite to the device. The conductive component is electrically connected to the cathode of the power module. The conductive component is at least partially disposed in the electroplating solution and is disposed adjacent to the edge of the device.

2. The electroplating apparatus as described in claim 1, characterized in that, The conductive element includes a current access point electrically connected to the power module, and the width of the conductive element gradually increases in the direction away from the current access point.

3. The plating apparatus as described in claim 1, characterized in that, The conductive element is ring-shaped and is arranged around the circumference of the device.

4. The electroplating apparatus according to any one of claims 1 to 3, characterized in that, The electroplating apparatus further includes a carrier on which at least one of the devices is fixed. The carrier is provided with a line electrically connected to the device. The carrier is electrically connected to the power module through the line. The conductive element is disposed on the carrier and electrically connected to the line.

5. The electroplating apparatus as described in claim 4, characterized in that, The carrier has a plurality of devices arranged in a matrix, the circuit is disposed between two adjacent devices, and the conductive element is disposed on the outer edge of each device away from the circuit.

6. The electroplating apparatus as described in claim 5, characterized in that, The conductive component includes a first conductive strip, a second conductive strip, a third conductive strip, and a fourth conductive strip connected end to end. A plurality of the components are located within the area enclosed by the first conductive strip, the second conductive strip, the third conductive strip, and the fourth conductive strip. The first conductive strip is electrically connected to the circuit and is located outside the electroplating solution. The second conductive strip and the fourth conductive strip are at least partially disposed in the electroplating solution, and the third conductive strip is located in the electroplating solution.

7. The electroplating apparatus as described in claim 6, characterized in that, The conductive element further includes a fifth conductive strip, which is connected between the second conductive strip and the fourth conductive strip, and is located between two adjacent components.

8. An electroplating method using the electroplating apparatus according to any one of claims 1 to 7, characterized in that, The electroplating method includes: The device to be electroplated and the conductive component are electrically connected to the cathode of the power module, and the electroplating anode is electrically connected to the anode of the power module. The device, the electroplating anode, and at least a portion of the conductive elements are disposed in the electroplating solution, with the conductive elements disposed adjacent to the device. When the power module is working, the conductive element can disperse the electric field lines at the edge of the device.

9. The electroplating method as described in claim 8, characterized in that, The conductive element is arranged circumferentially around the device; when the power module is working, the conductive element can disperse the electric field lines around the device.

10. The electroplating method as described in claim 8, characterized in that, At least one of the devices is fixed to the carrier and electrically connected to the wiring on the carrier, with the conductive element positioned away from the wiring.

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