Electroplating bath body for improving wafer film forming quality

Abstract

The utility model provides an electroplating bath body for improving wafer film forming quality, which is applied to the technical field of wafer electroplating and comprises a chamber base body, an anode cage, an ionic membrane frame, an ionic resistive element and a turbulent flow mechanism, a cation exchange membrane is mounted on the ionic membrane frame, and divides the chamber base body into an anode chamber and a cathode chamber; the anode cage is located in the anode chamber, a plurality of circular baffles are arranged on the anode cage, an annular structure is formed, the interior of the anode cage is divided into a plurality of annular areas, and the heights of the circular baffles are different; the ion resistive element and the turbulent flow mechanism are located in the cathode chamber, the ion resistive element is provided with an overflowing area, and the overflowing area is composed of a plurality of overflowing holes; the turbulent flow mechanism comprises a turbulent flow plate and a driving assembly, and the turbulent flow plate is driven by the driving assembly to do reciprocating translation. Through mutual cooperation of the anode cage, the ion resistive element and the turbulent flow mechanism, ion distribution and fluid movement in the cavity are regulated and controlled together, and the uniformity of ion and flow field distribution is improved.

Description

Technical Field

[0001] This utility model belongs to the field of wafer electroplating technology, specifically relating to an electroplating tank for improving the film formation quality of wafers. Background Technology

[0002] Wafer electroplating is one of the key processes in semiconductor manufacturing, mainly used to deposit a thin metal film on the surface of a wafer to enable circuit interconnection and functionality. During wafer electroplating, the wafer is typically placed in an electroplating solution, and an electric current is applied to reduce metal ions on the wafer surface and deposit them to form a thin metal film.

[0003] With the rapid development of semiconductor technology, the requirements for wafer electroplating processes are becoming increasingly stringent. Traditional wafer electroplating methods have many problems, such as uneven plating thickness, low plating efficiency, and difficulty in controlling plating quality. These problems seriously affect the performance and reliability of semiconductor devices.

[0004] To meet the manufacturing demands of high-performance semiconductor devices, scholars and engineers have conducted in-depth research on wafer electroplating processes, aiming to develop a wafer electroplating method capable of achieving efficient, uniform, and high-quality coatings. However, achieving efficient and uniform wafer electroplating still requires solving a series of technical challenges, such as optimizing the electroplating solution formulation, controlling electroplating parameters, and improving electroplating equipment. Therefore, developing a novel wafer electroplating method and apparatus is of great significance for improving the manufacturing level of semiconductor devices.

[0005] The invention patent with publication number CN118147727A proposes a wafer electroplating device, specifically including an electroplating chamber, an anode pool, a cathode pool, and an ion exchange membrane. By designing the anode plate and ion exchange membrane, the problem of the gradually increasing distance between the anode and cathode affecting the uniformity of the wafer plating layer in the prior art is solved.

[0006] The invention patent with publication number CN119372746A proposes an electroplating chamber and a wafer electroplating apparatus, including an electroplating chamber body and a surrounding groove for receiving and draining overflowing electroplating solution. This design prevents environmental pollution and production losses caused by electroplating solution overflow and improves wafer processing yield.

[0007] The invention patent with publication number CN118957713A discloses an electroplating tank device and a wafer electroplating equipment, including an electroplating tank device and a wafer electroplating equipment comprising a plating bath body and a disturbance mechanism. The driving component drives a disturbance plate to reciprocate within the electroplating chamber along a preset direction, thereby continuously agitating the air bubbles in the electroplating solution, causing them to quickly escape and eliminating bubbles adsorbed on the wafer surface. Furthermore, the agitation of the electroplating solution accelerates ion exchange, thereby improving the quality of the film formation.

[0008] The wafer electroplating method mentioned in the above patent is only a simplified design for the cavity and the stirring of the plating solution, and cannot solve the problems of uneven ion transport between the anode and cathode and uneven electric field distribution on the wafer surface caused by the circulation of the plating solution in the cavity. Utility Model Content

[0009] In view of the above-mentioned problems in the prior art, the purpose of this utility model is to provide an electroplating tank that improves the film formation quality of wafers. Through the cooperation between the anode cage, the ion resistive element, and the turbulence mechanism, the ion distribution and fluid movement in the chamber are jointly controlled, thereby improving the uniformity of ion distribution and flow field distribution and improving the film formation quality of wafers.

[0010] An electroplating tank for improving wafer film deposition quality includes a chamber substrate. Inside the chamber substrate are an anode cage, an ion exchange membrane frame, an ion resistive element, and a turbulence mechanism. A cation exchange membrane is mounted on the ion exchange membrane frame, dividing the interior of the chamber substrate into an anode chamber and a cathode chamber, each with its own independent plating solution circulation system. The anode cage is located within the anode chamber and is equipped with multiple circular baffles forming a ring structure that divides the interior of the anode cage into multiple annular regions, with the baffles having different heights. The ion resistive element and the turbulence mechanism are located within the cathode chamber, with the turbulence mechanism positioned above the ion resistive element. The ion resistive element has a flow area for ion passage, which is composed of multiple flow holes. The turbulence mechanism includes a turbulence plate and a driving assembly. The turbulence plate is driven by the driving assembly to reciprocate and vibrate.

[0011] Preferably, the turbulence plate includes a fixed frame and elongated plates. Multiple elongated plates are arranged sequentially within the fixed frame to form a grid structure. The surface of the elongated plates is curved and concave.

[0012] Preferably, the turbulence plate is mounted in the cathode chamber by two oppositely distributed supports. The two supports are respectively connected to a sliding member. The sliding member includes a sliding rail and a sliding plate that are slidably connected. The sliding rail is installed on an extension plate on the outer wall of the chamber substrate, and the sliding plate is connected to the support, so that the support drives the turbulence plate to move back and forth along the sliding rail.

[0013] Preferably, the drive assembly includes a motor, a rotating component, a rotating shaft, and a connecting component. The drive end of the motor is connected to the rotating component, the rotating component is connected to the connecting component via the rotating shaft, the rotating shaft and the drive end of the motor are not at the same axis position, and the connecting component is connected to one of the two sliding components.

[0014] Preferably, the ion exchange membrane frame is provided with a flow equalization block, which is a circular ring structure. The side wall of the flow equalization block has a plurality of flow equalization holes distributed in a circumferential array, and the outer side wall of the flow equalization block is provided with a groove for guiding the plating solution.

[0015] Preferably, conductive rods are respectively arranged in multiple annular areas of the anode cage, and guide members are arranged on the conductive rods. Guide holes are opened on the guide members, and external power lines are connected to the conductive rods through the guide holes of the guide members.

[0016] Preferably, an anode inlet and an anode overflow outlet are provided on the chamber substrate at positions corresponding to the anode chamber. Multiple anode inlets and outlets are provided and are uniformly distributed in a ring on the chamber substrate.

[0017] Preferably, a cathode inlet and a cathode overflow are provided on the chamber substrate at the position corresponding to the cathode chamber. The cathode inlet is connected to the flow equalization hole of the flow equalization block. Multiple cathode inlets and cathode overflows are provided and are uniformly distributed in a ring on the chamber substrate.

[0018] The beneficial effects of this utility model are: the electroplating tank for improving wafer film quality, through the structural design of the anode cage, divides the anode cage into multiple annular regions by circular baffles of different heights, thereby making the height of the anode metal particles that can be accumulated in different annular regions different, thus making the distance between the wafer and the anode metal particles in different regions different, thereby improving the electric field distribution on the wafer surface.

[0019] The ion resistive element is designed with a flow-through region, allowing ions to pass through the ion resistive element via the flow-through orifice, which can improve the uniformity of ion distribution.

[0020] The design and layout of the long strip plate on the turbulence plate can buffer and guide the flow of fluid, improving the uniformity of the flow field. In addition, the reciprocating translation of the turbulence plate by the drive mechanism can reduce bubbles on the wafer surface.

[0021] By combining the structural design and synergistic effect of the anode cage, ion resistive elements, and turbulence mechanism, the ion distribution and fluid motion within the chamber can be jointly controlled, thereby improving the uniformity of ion distribution and flow field distribution, and thus improving the film quality of the wafer. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0023] Figure 1 This is a cross-sectional view of the inside of the tank of this utility model;

[0024] Figure 2 This is a schematic diagram of the overall assembly structure of this utility model;

[0025] Figure 3 This is a schematic diagram showing the distribution of the internal components of the cavity in this utility model;

[0026] Figure 4 This is a schematic diagram of the structure of the chamber substrate of this utility model;

[0027] Figure 5 This is a schematic diagram of the structure of the ion resistive element of this utility model;

[0028] Figure 6 This is a schematic diagram of the flow equalization block of this utility model;

[0029] Figure 7 This is a schematic diagram of the structure of the ion membrane framework of this utility model;

[0030] Figure 8 This is a schematic diagram of the anode cage of this utility model;

[0031] Figure 9 This is a schematic diagram of the turbulence plate of this utility model;

[0032] Figure 10 This is a schematic diagram of the structure of this utility model. Figure 1 Enlarged view in the middle.

[0033] The following are labeled in the diagram: 1. Chamber substrate; 2. Ion resistive element; 3. Flow equalization block; 4. Ion membrane clamping component; 5. Ion membrane frame; 6. Anode cage; 7. Conductive rod; 8. Guide component; 9. Turbulence plate; 10. Motor; 11. Rotating component; 12. Rotating shaft; 13. Connecting component; 14. Sliding component; 15. Support; 16. Anode inlet; 17. Cathode inlet; 18. Anode overflow port; 19. Cathode overflow port. Detailed Implementation

[0034] Example 1

[0035] like Figure 1 , Figure 3 As shown, an electroplating tank for improving wafer film formation quality includes a chamber substrate 1, and the chamber substrate 1 is internally configured with an anode cage 6, an ion membrane frame 5, an ion resistive element 2, and a turbulence mechanism.

[0036] The interior of the chamber substrate 1 is divided into an anode chamber and a cathode chamber by a cation exchange membrane. The cathode chamber is located above the anode chamber, and the anode chamber and cathode chamber each have independent plating solution circulation systems.

[0037] The cation exchange membrane is pressed and fixed onto the ion membrane frame 5 by the ion membrane clamping component 4. For example... Figure 7As shown, the ion exchange membrane frame 5 is disc-shaped, and the cation exchange membrane fixed on the ion exchange membrane frame 5 has a certain degree of downward indentation, so that the cation exchange membrane can be embedded in the anode chamber, so that the plating solution in the anode chamber and the cathode chamber can be in better contact, and it is also conducive to the discharge of bubbles.

[0038] like Figure 1 , Figure 3 As shown, a flow equalization block 3 is also disposed on the ion membrane frame 5, and the flow equalization block 3 is located in the cathode chamber. Figure 6 As shown, the flow equalization block 3 has a circular ring structure. The side wall of the flow equalization block 3 has multiple flow equalization holes arranged in a circular array. The outer side wall of the flow equalization block 3 has a groove for guiding the plating solution.

[0039] The anode cage 6 is installed at the bottom of the anode chamber and is used to hold the anode metal particles. For example... Figure 8 As shown, the anode cage 6 is equipped with multiple circular baffles made of insulating material. The height of each circular baffle is different, with the height of the circular baffles closer to the center of the anode cage 6 being higher, forming a stepped distribution. The multiple circular baffles form a ring structure, thereby dividing the interior of the anode cage 6 into multiple annular regions. The height of the anode metal particles that can be placed in each annular region is different. Therefore, the distance from the wafer to the anode metal particles at different heights is different, which can improve the electric field distribution on the wafer surface and improve the wafer film quality.

[0040] Among them, such as Figure 8 As shown, each annular region of the anode cage 6 is provided with a through hole for connection to the conductive rod 7, such as... Figure 1 , Figure 3 As shown, the conductive rod 7 is equipped with a guide member 8, which has a guide hole for guiding the external power cord, so that the power cord can be connected to the conductive rod 7 to achieve conductivity. The guide member 8 also protects the conductive rod 7.

[0041] like Figure 1 , Figure 3 , Figure 4 As shown, the ion resistive element 2 is located inside the cathode chamber and mounted on the chamber substrate 1. The structure of the ion resistive element 2 is as follows: Figure 5 As shown, the ion resistive element 2 is provided with a flow-through region for ion passage. This flow-through region consists of multiple flow-through holes to improve the uniformity of ion distribution. Figure 1 As shown, the thickness of the flow region of the ion resistive element 2 varies, with the thickness being the smallest at the center position. Therefore, the length of the flow orifice varies. The structural design of the ion resistive element 2 can improve the uniformity of ion distribution and flow field distribution.

[0042] like Figure 1 , Figure 2As shown, the turbulence mechanism is installed inside the cathode chamber. The turbulence mechanism includes a drive assembly and a turbulence plate 9. The turbulence plate 9 is mounted above the ion resistive element 2 via a support 15. The drive assembly is connected to the support 15 and is used to drive the turbulence plate 9 to reciprocate parallel to each other in a preset direction. The continuous reciprocating movement of the turbulence plate 9 generates vibration, which is used to reduce bubbles in the electroplating solution, thereby eliminating bubbles attached to the wafer surface.

[0043] like Figure 9 As shown, the turbulence plate 9 includes a fixed frame and multiple strip plates, which are arranged sequentially within the fixed frame to form a grid structure. It is important to note that the surface of the strip plates is curved and concave, which can buffer and guide the flow according to the different impact forces of the fluid, making the flow field of the electroplating solution more uniform.

[0044] Furthermore, a bracket 15 is connected to each of the two opposite sides of the turbulence plate 9. The two brackets 15 are respectively connected to the sliding member 14. The sliding member 14 includes a sliding rail and a sliding plate. The sliding rail is installed on the extension plate on the outer wall of the chamber base 1. The sliding plate is connected to the bracket 15, so that the bracket 15 can drive the turbulence plate 9 to move back and forth along the sliding rail.

[0045] like Figure 1 , Figure 10 As shown, the drive assembly includes a motor 10, a rotating component 11, a rotating shaft 12, and a connecting component 13. The drive end of the motor 10 is connected to the rotating component 11, and the rotating component 11 is connected to the connecting component 13 via the rotating shaft 12. Furthermore, the rotating shaft 12 and the drive end of the motor 10 are not located on the same axis. The connecting component 13 is connected to one of the two sliding components 14.

[0046] The motor 10 drives the rotating component 11 to drive the rotating shaft 12 to rotate on different axes, thereby driving the connecting component 13 to drive the bracket 15 to move back and forth along the slide rail of the sliding component 14 by relying on the sliding component 14, thereby driving the turbulence plate 9 to vibrate, which helps to reduce bubbles in the electroplating solution.

[0047] like Figure 1 , Figure 2 , Figure 4 As shown, an anode inlet 16 and an anode overflow outlet 18 are arranged on the chamber substrate 1 at the positions corresponding to the anode chamber. The plating solution enters the anode chamber through the anode inlet 16 and overflows from the anode overflow outlet 18 after reaching a certain height in the anode chamber. There are multiple anode inlets 16 and anode overflow outlets 18, which are uniformly distributed in a ring on the chamber substrate 1.

[0048] A cathode inlet 17 and a cathode overflow outlet 19 are disposed on the chamber substrate 1 at positions corresponding to the cathode chamber. The cathode inlet 17 is connected to the flow equalization hole of the flow equalization block 3. The plating solution enters the cathode chamber through the cathode inlet 17, and after being evenly distributed by the flow equalization block 3, it enters the cathode chamber. When the plating solution reaches a certain height in the cathode chamber, it overflows through the cathode overflow outlet 19. Multiple cathode inlets 17 and cathode overflow outlets 19 are provided and are uniformly distributed in a ring on the chamber substrate 1.

[0049] Working principle: In this electroplating tank that improves wafer film formation quality, the positive electrode wire is connected to the conductive rod 7 via the guide 8. Anode metal particles are filled into the anode cage 6, and the height of the anode metal particles in different ring areas corresponds to the different heights of the circular baffles in the anode cage 6. According to the design of the stepped platform inside the chamber substrate 1, the ion membrane frame 5, the flow equalization block 3, the ion resistive element 2, and the turbulence plate 9 are installed sequentially from bottom to top.

[0050] Plating solution is injected into the anode chamber through the anode inlet 16. After reaching a certain height in the anode chamber, the plating solution overflows through the anode overflow outlet 18. The plating solution circulates within the anode chamber through the anode inlet 16 and the anode overflow outlet 18. Simultaneously, plating solution is injected into the cathode chamber through the cathode inlet 17. The cathode plating solution enters the cathode chamber after being evenly distributed by the flow equalization block 3. When the plating solution reaches a certain height in the cathode chamber, it overflows through the cathode overflow outlet 19. The plating solution circulates within the cathode chamber through the cathode inlet 17 and the cathode overflow outlet 19.

[0051] Adjust the plating solution temperature, and regulate the pressure and flow rate at the plating solution inlet. Once the plating solution temperature stabilizes and chamber circulation is achieved, immerse the clamped wafer into the plating solution in the cathode chamber and connect it to the cathode via the negative electrode wire. Power on the positive and negative electrode wires and start motor 10 simultaneously to begin the wafer electroplating operation.

[0052] Through the structural design and synergistic effect of the anode cage 6, ion resistive element 2, and turbulence mechanism, the ion distribution and fluid motion within the chamber are jointly controlled, improving the uniformity of ion distribution and flow field distribution, thereby enhancing the film quality of the wafer.

[0053] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An electroplating tank for improving wafer film formation quality, characterized in that, It includes a chamber substrate (1), and the interior of the chamber substrate (1) is configured with an anode cage (6), an ion membrane frame (5), an ion resistive element (2) and a turbulence mechanism; A cation exchange membrane is installed on the ion membrane frame (5). The cation exchange membrane divides the interior of the chamber substrate (1) into an anode chamber and a cathode chamber. The anode chamber and the cathode chamber each have an independent plating solution circulation system. The anode cage (6) is located in the anode chamber. The anode cage (6) is equipped with multiple circular baffles. The multiple circular baffles form a ring structure and divide the interior of the anode cage (6) into multiple annular regions. The heights of the multiple circular baffles are different. The ion resistive element (2) and the turbulence mechanism are located in the cathode chamber. The turbulence mechanism is located above the ion resistive element (2). The ion resistive element (2) is provided with a flow area for ions to pass through. The flow area is composed of multiple flow holes. The turbulence mechanism includes a turbulence plate (9) and a driving assembly. The turbulence plate (9) is driven by the driving assembly to reciprocate and move to form vibration.

2. The electroplating tank for improving wafer film quality according to claim 1, characterized in that, The turbulence plate (9) includes a fixed frame and long strips. Multiple long strips are arranged sequentially within the fixed frame to form a grid structure. The surface of the long strips is curved and concave.

3. The electroplating tank for improving wafer film quality according to claim 1, characterized in that, The turbulence plate (9) is mounted in the cathode chamber by two oppositely distributed supports (15). The two supports (15) are respectively connected to the sliding member (14). The sliding member (14) includes a sliding rail and a sliding plate connected in a sliding manner. The sliding rail is installed on the extension plate on the outer wall of the chamber base (1). The sliding plate is connected to the support (15), so that the support (15) drives the turbulence plate (9) to move back and forth along the sliding rail.

4. The electroplating tank for improving wafer film quality according to claim 3, characterized in that, The drive assembly includes a motor (10), a rotating component (11), a rotating shaft (12), and a connecting component (13). The drive end of the motor (10) is connected to the rotating component (11), and the rotating component (11) is connected to the connecting component (13) through the rotating shaft (12). The rotating shaft (12) and the drive end of the motor (10) are not at the same axis position. The connecting component (13) is connected to one of the two sliding components (14).

5. The electroplating tank for improving wafer film quality according to claim 1, characterized in that, The ion membrane frame (5) is provided with a flow equalization block (3), which is a ring structure. The side wall of the flow equalization block (3) is provided with a plurality of flow equalization holes arranged in a circumferential array. The outer side wall of the flow equalization block (3) is provided with a groove for guiding the plating solution.

6. The electroplating tank for improving wafer film quality according to claim 1, characterized in that, Conductive rods (7) are respectively arranged in multiple annular areas of the anode cage (6). Guide members (8) are arranged on the conductive rods (7). Guide holes are opened on the guide members (8). External power lines are connected to the conductive rods (7) through the guide holes of the guide members (8).

7. The electroplating tank for improving wafer film quality according to claim 1, characterized in that, The chamber substrate (1) is provided with an anode inlet (16) and an anode overflow outlet (18) at the position corresponding to the anode chamber. There are multiple anode inlets (16) and anode overflow outlets (18), which are uniformly distributed in a ring on the chamber substrate (1).

8. The electroplating tank for improving wafer film quality according to claim 1, characterized in that, The chamber substrate (1) is provided with a cathode inlet (17) and a cathode overflow outlet (19) at the position corresponding to the cathode chamber. The cathode inlet (17) is connected to the flow equalization hole of the flow equalization block (3). There are multiple cathode inlets (17) and cathode overflow outlets (19), which are uniformly distributed in a ring on the chamber substrate (1).

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