Wafer electroplating process for improving binding force between composite coatings and process treatment equipment

Abstract

According to the wafer electroplating technology and technology processing equipment for improving the binding force between the composite plating layers, compared with a conventional electroplating technology, the specially-designed sulfuric acid pickling step is added after the copper plating step and the nickel plating step are finished, and therefore the bonding force between the composite plating layers is improved; passivating films formed by oxidation on the surfaces of the copper plating layer and the nickel plating layer of the wafer are eliminated, and then the binding force between the plating layers is improved. The wafer electroplating process treatment equipment comprises a sealed treatment chamber, the sealed treatment chamber comprises a plurality of small sealed cavities, the small sealed cavities comprise an acid pickling cavity and an electroplating cavity, and a double-port nozzle device capable of alternately spraying dilute sulphuric acid and ultrapure water to the surface of a wafer is arranged in the acid pickling cavity so that a passivation layer on the surface of the wafer can be mildly corroded; the sealed processing chamber and the sealed small chambers are vacuumized, so that secondary oxidation of the wafer in the electroplating, pickling or inter-chamber transfer process is prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of wafer electroplating processes. Specifically, it relates to a wafer process treatment device for improving the bonding strength between composite coatings and a wafer electroplating process using this device. Background Art

[0002] Wafer electroplating is a process of forming a metal thin film or other material thin film on the surface of a wafer. By immersing a cylindrical electrode of a metal ingot or other material into mercury, metal or other conductive materials are deposited on the wafer surface through electrolysis.

[0003] The application of wafer electroplating is very extensive and is mainly used in the manufacturing of semiconductor devices. With the rapid rise of the microelectronics industry, wafer electroplating technology has also developed rapidly, and the wafer electroplating process has become more and more complex and precise. In many specific fields, it is necessary to electroplate multiple layers of metal and the bonding between the metal and the substrate surface and between the metal coatings is stable and reliable. Therefore, a wafer electroplating machine is required to include pre-treatment, post-treatment processes and control to achieve micron-level thin film coating control and reliable deposition. To solve the reliable and stable deposition between composite electroplated layers, controlling the intermolecular bonding strength is the key.

[0004] One of the applications of wafer surface treatment with metal or alloy plating is to slow down the corrosion degree of semiconductor components. With the development of modern science and technology and modern industry, the requirements for wafer protective coatings are getting higher and higher; traditional single-layer metal (or alloy) films can no longer fully meet the requirements. Currently, the conventional composite coating electroplating processes in the industry, such as Figure 1 shown, during the electroplating process, the current mainstream electroplating composite metal layer sequence is to electroplate Cu, Ni, and Au on the substrate in sequence. However, in the actual production process, when using the above conventional electroplating process flow to electroplate Cu, Ni, and Au coatings on the wafer substrate, there is a poor bonding strength between the substrate plating surface and the coating or between the coatings, resulting in pitting corrosion, coating blistering, or coating separation when processing the Cu, Ni, and Au composite metal layer during subsequent production, handling, or processing. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a wafer electroplating process and a process treatment device for improving the bonding strength between composite coatings to solve the technical problems existing in the prior art, such as poor bonding strength between metal composite layers, poor appearance of the final product plating surface, easy peeling off, and inability to meet the performance requirements of semiconductor components.

[0006] According to a first aspect of the present invention, there is provided a wafer electroplating process treatment device for improving the bonding strength between composite coatings, including a sealed treatment chamber, which includes a number of sealed small chambers. The sealed small chambers are composed of an electroplating chamber and a pickling chamber. The electroplating chamber is used for electroplating, and the pickling chamber is used for pickling;

[0007] The sealed treatment chamber is connected to a first vacuum pumping device, and the first vacuum pumping device can keep the inside of the sealed treatment chamber in a primary vacuum state. The sealed small chamber is connected to a second vacuum pumping device, and the second vacuum pumping device can keep the inside of the sealed small chamber in a secondary vacuum state;

[0008] An elastic sealing structure is provided at the chamber entrance of the sealed small chamber. When the electroplating head holds the wafer and descends into the sealed small chamber for pickling or electroplating, the elastic sealing structure at the chamber entrance presses against the side of the electroplating head;

[0009] A double-port nozzle including an acid nozzle and a water nozzle is provided on the side wall of the pickling chamber. The acid nozzle is connected to a dilute sulfuric acid storage tank, and the water nozzle is connected to an ultrapure water storage tank. The double-port nozzle alternately sprays dilute sulfuric acid and ultrapure water onto the wafer surface under the control of a pulse process.

[0010] The wafer electroplating process treatment device provided by this technical solution is used to gently corrode the passivation layer formed by oxidation of the wafer plating surface in a sealed chamber. By alternately spraying dilute sulfuric acid and ultrapure water onto the wafer plating surface using the double-port nozzle in the pickling system, where the dilute sulfuric acid is used to corrode and eliminate the passivation layer, and at the same time spraying ultrapure water onto the plating surface, it can quickly neutralize to reduce or eliminate the roughness that may be caused during the process of corroding and oxidizing the oxide layer.

[0011] In addition, since the wafer is in the process states of electroplating and pickling, the elastic material and the pre-tightening spring at the chamber entrance will press against the side of the electroplating head, thereby making the inside of the sealed small chamber in a relatively sealed state. Performing steps such as electroplating, cleaning, and pickling of the wafer in the sealed state of the chamber can avoid the risk of secondary oxidation of the wafer and can isolate the air from contacting the electroplating stock solution.

[0012] Preferably, two electroplating chambers and one or two pickling chambers are provided in the sealed treatment chamber; the two electroplating chambers are a copper plating chamber and a nickel plating chamber respectively.

[0013] In this technical solution, since the gold element is relatively stable and not easily oxidized, and the electroplating head holds the wafer and transfers it very quickly, therefore, the gold plating chamber can be arranged outside the treatment chamber. Since copper and nickel elements are easily oxidized, the copper plating chamber and the nickel plating chamber should be placed in the sealed treatment chamber with vacuum treatment to reduce the oxidation degree of the copper coating and the nickel coating and improve the electroplating quality.

[0014] When there is one pickling chamber in the processing chamber, the pickling steps after copper plating and after nickel plating both occur in one pickling chamber. If there are two wafers undergoing copper plating and nickel plating respectively in the same processing chamber at the same time, pickling will be carried out after both copper plating and nickel plating are completed. At this time, the wafers after copper plating and the wafers after nickel plating will compete for the same pickling chamber for pickling. It can be seen that it is difficult for one pickling chamber to simultaneously perform pickling after copper plating and pickling after nickel plating for multiple wafers. Therefore, the situation where the sealed processing chamber contains one pickling chamber is only applicable to laboratory verification and electroplating processing in small production lines. If large-scale batch electroplating processing is to be carried out, two pickling chambers need to be provided in the sealed processing chamber, which are respectively located after the copper plating chamber and the nickel plating chamber, so as to perform pickling after copper plating and pickling after nickel plating respectively, which is beneficial to improving the efficiency of large-scale electroplating processing.

[0015] Preferably, a gold plating chamber is further included in the sealed processing chamber.

[0016] In this technical solution, putting the gold plating chamber into the processing chamber can further prevent the wafers from being oxidized during the process of transferring from the nickel plating pickling to the gold plating chamber, thereby improving the electroplating quality.

[0017] According to the second aspect of the present invention, there is provided a wafer electroplating process treatment device for improving the bonding force between composite coatings, including a sealed processing chamber, and several integrated electroplating pickling chambers are included in the sealed processing chamber;

[0018] The sealed processing chamber is connected to a first vacuum pumping device, and the first vacuum pumping device can keep the inside of the sealed processing chamber in a primary vacuum state. The integrated electroplating pickling chamber is connected to a second vacuum pumping device, and the second vacuum pumping device can keep the inside of the integrated electroplating pickling chamber in a secondary vacuum state;

[0019] The integrated electroplating pickling chamber includes, from bottom to top in the vertical direction, a plating area, a cleaning area, and a pickling area that are interconnected. The plating area, the cleaning area, and the pickling area respectively perform electroplating process, cleaning process, and pickling process;

[0020] A chamber inlet is provided at the top of the pickling area, and an elastic sealing structure is provided at the chamber inlet. When the electroplating head holds the wafer and descends into the integrated electroplating pickling chamber for pickling, cleaning, or electroplating, the elastic sealing structure at the chamber inlet presses against the side of the electroplating head;

[0021] A double-port nozzle including an acid nozzle and a water nozzle is provided on the side wall of the pickling area. The acid nozzle is connected to a dilute sulfuric acid storage tank, and the water nozzle is connected to an ultrapure water storage tank. The double-port nozzle alternately sprays dilute sulfuric acid and ultrapure water on the wafer surface under the control of a pulse process;

[0022] The cleaning area includes several fan-shaped nozzles, and the fan-shaped nozzles are used to spray ultrapure water for cleaning.

[0023] The wafer electroplating process treatment equipment for improving the bonding strength between composite coatings provided by this technical solution integrates wafer electroplating and pickling in one chamber, avoiding the possible oxidation risk during the transfer of the wafer from one electroplating chamber to the pickling chamber. Meanwhile, a cleaning area is added to clean the entire chamber after electroplating and pickling are completed, preventing cross-contamination between the electroplating solution and the pickling solution.

[0024] In addition, since both the sealed treatment chamber and the integrated electroplating and pickling chamber are evacuated, the wafer undergoes steps such as electroplating, cleaning, and pickling in the sealed state of the chamber, which can avoid the risk of secondary oxidation of the wafer and isolate the air from contacting the electroplating stock solution.

[0025] Preferably, the electroplating area is provided with a liquid inlet, a liquid outlet, and an overflow port, and the liquid inlet, the liquid outlet, and the overflow port are all connected to a liquid storage tank storing electroplating solution; the liquid outlet is provided with a three-way valve, and the three-way valve is provided with an electroplating solution valve port and a waste liquid valve port; the inner wall of the bottom of the electroplating area inclines towards the center to form an inverted cone shape.

[0026] In this technical solution, by setting a three-way valve at the liquid outlet, the electroplating solution valve port and the waste liquid valve port of the three-way valve can be switched when discharging waste liquid formed in different areas. Among them, the electroplating solution valve port is used to discharge electroplating solution, and the waste liquid valve port is used to discharge the waste liquid generated by the self-purification of the chamber, which is beneficial to the alternate connection between the electroplating step and the pickling step. In addition, the inner wall of the bottom of the sealed chamber is designed to incline towards the center, which is beneficial to discharging the liquid from the chamber without dead corners of residual liquid and avoiding the residue of waste liquid.

[0027] Preferably, a reflux tank and a reflux tank reflux port are further provided on the side wall of the pickling area; the reflux tank is an overall hollow ring arranged along the inner wall of the pickling area chamber, one end of which is connected to the side chamber wall of the pickling area, and the upper part of the other end extends upward to form a groove part with the side chamber wall of the pickling area for collecting the pickling waste liquid thrown out during pickling; the reflux tank reflux port is used to discharge the pickling waste liquid collected by the reflux tank.

[0028] Preferably, a gold plating chamber is further included in the sealed treatment chamber.

[0029] Since the gold element itself is relatively stable and not easily oxidized, therefore, the gold plating chamber can be placed outside the treatment chamber, but in this technical solution, placing the gold plating chamber in the sealed treatment chamber can further reduce the oxidation risk and thus improve the electroplating quality.

[0030] Preferably, the pressure range of the first-level vacuum state is -200 to -800 Pa, and the pressure range of the second-level vacuum state is -5000 to -15000 Pa, where the pressure of the second-level vacuum state is lower than that of the first-level vacuum state.

[0031] Preferably, the concentration of the dilute sulfuric acid is 5%.

[0032] According to the third aspect of the present invention, there is provided an electroplating process for improving the bonding strength between composite coatings, including copper electroplating, nickel electroplating, and gold electroplating. The wafer electroplating process equipment for improving the bonding strength between composite coatings described above is used to sequentially perform copper electroplating and nickel electroplating, including the following steps:

[0033] S10. Vacuum pumping: The sealed treatment chamber and the sealed small chamber are subjected to vacuum pumping to keep the sealed treatment chamber in a first-level vacuum state and the sealed small chamber in a second-level vacuum state;

[0034] S20. Copper plating and spin-drying: The wafer is transferred into the copper plating chamber by the electroplating head to deposit metallic Cu on the wafer surface. After the copper electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then the electroplating head drives the wafer to rise and leave the copper plating chamber;

[0035] S30. Pickling and spin-drying: The wafer that has completed copper electroplating is quickly transferred into the pickling chamber by the electroplating head for pickling. The double-port nozzle alternately sprays dilute sulfuric acid and ultrapure water onto the wafer surface under the control of the pulse process. After pickling is completed, the electroplating head drives the wafer to rotate and spin-dry, and then the electroplating head drives the wafer to rise and leave the pickling chamber;

[0036] S40. Nickel plating and spin-drying: The wafer is transferred into the nickel plating chamber by the electroplating head to deposit metallic Ni on the wafer surface. After the nickel electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then the electroplating head drives the wafer to rise and leave the nickel plating chamber;

[0037] S50. Pickling and spin-drying: The wafer that has completed nickel electroplating is quickly transferred into the pickling chamber by the electroplating head for pickling. The double-port nozzle alternately sprays dilute sulfuric acid and ultrapure water onto the wafer surface under the control of the pulse process. After pickling is completed, the electroplating head drives the wafer to rotate and spin-dry, and then the electroplating head drives the wafer to rise and leave the pickling chamber; At the same time, the electroplating head drives the wafer to leave the sealed treatment chamber;

[0038] S60. Gold plating and spin-drying: The wafer is transferred into the gold plating chamber by the electroplating head to deposit metallic Au on the wafer surface. After the gold electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then the electroplating head drives the wafer to rise and leave the gold plating chamber;

[0039] S70. Cleaning: The wafer after gold plating is transferred into the cleaning chamber by the electroplating head for cleaning the wafer surface.

[0040] In this technical solution, different from the electroplating process of conventional composite coatings, a sulfuric acid pickling step is added on the basis of the conventional electroplating process flow, which can effectively eliminate the passivation layer on the wafer surface. Moreover, the pickling and DIW alternating process of the present invention has a mild corrosion effect on the oxide layer of the wafer plating surface and the rapid neutralization effect of DIW can reduce or eliminate the possible increase in roughness during the process of corroding the oxide layer, realizing the removal of the passivation film cleanly without damaging the flatness and roughness of the wafer metal plating surface. At the same time, both the processing chamber and the small chamber are evacuated. Therefore, whether it is the wafer electroplating or pickling process carried out in the small chamber, or the transfer of the wafer from one chamber to another chamber carried out in the processing chamber, the contact between the plated parts and oxygen can be controlled to prevent the occurrence of secondary oxidation.

[0041] According to the fourth aspect of the present invention, there is provided an electroplating process for improving the bonding strength between composite coatings. Using the above-mentioned wafer electroplating process equipment for improving the bonding strength between composite coatings, copper electroplating, nickel electroplating and gold electroplating are carried out in sequence, including the following steps:

[0042] S10. Evacuation: Evacuate the sealed processing chamber and the sealed small chamber to keep the sealed processing chamber in a first-level vacuum state and the sealed small chamber in a second-level vacuum state;

[0043] S20. Copper plating and spin-drying: Move the wafer into the copper plating chamber through the electroplating head to deposit metal Cu on the wafer surface. After the copper electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then, the electroplating head drives the wafer to rise and leave the copper plating chamber;

[0044] S30. Pickling and spin-drying: Quickly transfer the wafer that has completed copper electroplating into the pickling chamber through the electroplating head for the pickling step, so that the double-nozzle sprays dilute sulfuric acid and ultrapure water alternately on the wafer surface under the control of the pulse process. After pickling is completed, the electroplating head drives the wafer to rotate and spin-dry, and then, the electroplating head drives the wafer to rise and leave the pickling chamber;

[0045] S40. Nickel plating and spin-drying: Move the wafer into the nickel plating chamber through the electroplating head to deposit metal Ni on the wafer surface. After the nickel electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then, the electroplating head drives the wafer to rise and leave the nickel plating chamber;

[0046] S50. Pickling and spin-drying: Quickly transfer the wafer that has completed nickel electroplating into the pickling chamber through the electroplating head for the pickling step, so that the double-nozzle sprays dilute sulfuric acid and ultrapure water alternately on the wafer surface under the control of the pulse process. After pickling is completed, the electroplating head drives the wafer to rotate and spin-dry, and then, the electroplating head drives the wafer to rise and leave the pickling chamber;

[0047] S60, Gold Plating and Spinning Dry: The electroplating head moves the wafer into the gold plating chamber to deposit metal Au on the wafer surface. After the gold electroplating is completed, the electroplating head drives the wafer to rise and spin dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber; subsequently, the electroplating head drives the wafer to leave the sealed processing chamber;

[0048] S70, Cleaning: The electroplating head moves the gold-plated wafer into the cleaning chamber for cleaning the wafer surface.

[0049] In this technical solution, the process of gold plating and spinning dry is also carried out in the sealed processing chamber, which can further reduce the oxidation that may occur during the transfer of the wafer from the pickling chamber to the gold plating chamber, thereby improving the electroplating quality.

[0050] According to the fifth aspect of the present invention, there is provided an electroplating process for improving the bonding strength between composite coatings, including copper electroplating, nickel electroplating, and gold electroplating. The wafer electroplating process equipment for improving the bonding strength between composite coatings described above is used to sequentially perform copper electroplating and nickel electroplating, including the following steps:

[0051] S10, Evacuating the sealed processing chamber to maintain a primary vacuum state in the sealed processing chamber and a secondary vacuum state in the integrated electroplating pickling chamber;

[0052] S20, Copper Plating and Pickling: The electroplating head holds the wafer and enters the Cu integrated electroplating pickling chamber and descends to the electroplating area to start wafer electroplating. After the Cu electroplating is completed, the electroplating head drives the wafer to rise and spin dry; after spinning dry, the sector nozzles in the cleaning area are opened to clean the integrated electroplating pickling chamber, and then dried with nitrogen. Then, the electroplating head drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface; after pickling is completed, the chamber is cleaned again; subsequently, the electroplating head drives the wafer out of the Cu integrated electroplating pickling chamber;

[0053] S30, Nickel Plating and Pickling: The electroplating head holds the wafer and enters the Ni integrated electroplating pickling chamber and descends to the electroplating area to start wafer electroplating. After the Ni electroplating is completed, the electroplating head drives the wafer to rise and spin dry; after spinning dry, the sector nozzles in the cleaning area are opened to clean the integrated electroplating pickling chamber, and then dried with nitrogen. Then, the electroplating head drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface; after pickling is completed, the chamber is cleaned again; subsequently, the electroplating head drives the wafer out of the Ni integrated electroplating pickling chamber; finally, the electroplating head drives the wafer to leave the sealed processing chamber;

[0054] S40, Gold Plating and Spin Drying: The wafer is transferred into the gold plating chamber by the electroplating head to deposit metallic Au on the wafer surface. After the gold electroplating is completed, the electroplating head drives the wafer to rise and spin dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber;

[0055] S50, Cleaning: The electroplating head transfers the wafer after gold plating into the cleaning chamber for cleaning the wafer surface.

[0056] In this technical solution, the electroplating and pickling of the wafer occur in an integrated chamber, enabling the pickling of the surface passivation film of the wafer directly in the same chamber after the electroplating of the wafer is completed, avoiding the possible oxidation risk during the transfer of the wafer from the electroplating chamber to the pickling chamber.

[0057] According to the sixth aspect of the present invention, there is provided an electroplating process for improving the bonding strength between composite coatings, including copper electroplating, nickel electroplating, and gold electroplating. The wafer electroplating process equipment for improving the bonding strength between composite coatings described above is used to perform copper electroplating, nickel electroplating, and gold electroplating in sequence, including the following steps:

[0058] S10, Perform vacuum pumping on the sealed treatment chamber to keep the sealed treatment chamber in a primary vacuum state and the integrated electroplating and pickling chamber in a secondary vacuum state;

[0059] S20, Copper Plating and Pickling: The electroplating head holds the wafer and enters the Cu integrated electroplating and pickling chamber and descends to the electroplating area to start wafer electroplating. After the Cu electroplating is completed, the electroplating head drives the wafer to rise and spin dry; after spin drying, the sector nozzles in the cleaning area are opened to clean the integrated electroplating and pickling chamber, and it is dried with nitrogen. Then, it drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating and pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface; after pickling is completed, the chamber is cleaned again; subsequently, the electroplating head drives the wafer out of the Cu integrated electroplating and pickling chamber;

[0060] S30, Nickel Plating and Pickling: The electroplating head holds the wafer and enters the Ni integrated electroplating and pickling chamber and descends to the electroplating area to start wafer electroplating. After the Ni electroplating is completed, the electroplating head drives the wafer to rise and spin dry; after spin drying, the sector nozzles in the cleaning area are opened to clean the integrated electroplating and pickling chamber, and it is dried with nitrogen. Then, it drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating and pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface; after pickling is completed, the chamber is cleaned again; subsequently, the electroplating head drives the wafer out of the Ni integrated electroplating and pickling chamber;

[0061] S40, Gold Plating and Spin Drying: The wafer is transferred into the gold plating chamber by the electroplating head to deposit metal Au on the wafer surface. After the gold plating is completed, the electroplating head drives the wafer to rise and spin dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber. Finally, the electroplating head drives the wafer out of the sealing treatment chamber;

[0062] S50, Cleaning: The electroplating head transfers the wafer after gold plating into the cleaning chamber for cleaning the wafer surface.

[0063] In this technical solution, not only are the electroplating and pickling steps integrated in one chamber, reducing the possible oxidation during the transfer of the wafer between pickling and electroplating; moreover, the process of gold plating and spin drying is also carried out in the sealing treatment chamber, which can further reduce the possible oxidation during the transfer of the wafer from the pickling chamber to the gold plating chamber, thereby improving the electroplating quality.

[0064] Preferably, in the pickling step, the concentration of dilute sulfuric acid is 5%, and dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternate spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds.

[0065] Compared with the prior art, the present invention has the following beneficial effects:

[0066] 1. Solve the problem that the passivation film formed when the wafer is exposed to air has a negative impact on the bonding force between the coatings: The pickling and ultrapure water alternating use process of the present invention has a mild corrosion effect on the oxide layer on the wafer plating surface, and the effect of quickly neutralizing with ultrapure water can reduce or eliminate the possible increase in roughness during the process of corroding the oxide layer, realizing the removal of the passivation film cleanly without damaging the flatness and roughness of the wafer metal plating surface, so as to improve the bonding force between the composite coatings.

[0067] 2. Solve the problem of secondary oxidation of the workpiece in contact with oxygen during the process of removing the oxide layer: The present invention designs a sealed chamber system for the entire electroplating pickling process, including several sealed small chambers and a sealing treatment chamber containing several small chambers, which respectively maintain a secondary vacuum and a primary vacuum state. Carrying out in the sealed chamber system can avoid the secondary oxidation of the wafer during the processes of electroplating, pickling, and transfer between chambers, and realize the stable and reliable bonding deposition between the coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] By reading the detailed description of the non - restrictive embodiments with reference to the following drawings, other features, objects, and advantages of the present invention will become more obvious:

[0069] Figure 1 It is a process flow chart of the mainstream wafer metal composite layer electroplating process in the prior art;

[0070] Figure 2Schematic diagram of the electroplating process treatment equipment for improving the bonding strength between composite coatings described in Example 1;

[0071] Figure 3 Schematic diagram of the structure of the electroplating chamber described in Example 1 and Example 2;

[0072] Figure 4 Schematic diagram of the structure of the pickling chamber described in Example 1 and Example 2;

[0073] Figure 5 Schematic diagram of the electroplating process treatment equipment for improving the bonding strength between composite coatings described in Example 2;

[0074] Figure 6 Schematic diagram of the structure of the integrated electroplating and pickling chamber described in Example 3;

[0075] Figure 7 Schematic diagram of the electroplating process treatment equipment for improving the bonding strength between composite coatings described in Example 3;

[0076] Figure 8 Flow chart of the electroplating process for improving the bonding strength between composite coatings described in Example 4;

[0077] Figure 9 Flow chart of the electroplating process for improving the bonding strength between composite coatings described in Example 5;

[0078] Figure 10 Flow chart of the electroplating process for improving the bonding strength between composite coatings described in Example 6;

[0079] Figure 11 Flow chart of the electroplating process for improving the bonding strength between composite coatings described in Example 7;

[0080] Explanation of reference numerals:

[0081] 1 - Sealed treatment chamber 2 - Copper plating chamber 3 - Nickel plating chamber

[0082] 4 - Gold plating chamber 5 - Liquid storage tank 6 - Electroplating head

[0083] 7 - Pickling chamber 8 - Pickling chamber after copper plating 9 - Pickling chamber after nickel plating

[0084] 10 - Double - port nozzle 11 - Liquid storage box 12 - Pre - tightening spring

[0085] 13 - Return flow tank 14 - Return flow port of the return flow tank 15 - Cu integrated electroplating and pickling chamber

[0086] 16 - Ni integrated electroplating and pickling chamber 17 - Three - way valve 20 - Sector nozzle Detailed implementation manners

[0087] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the accompanying drawings in the embodiments of this application. Apparently, the described embodiments are some, but not all, of the embodiments of this application. Usually, the components of the embodiments of this application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0088] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts fall within the scope of protection of this application.

[0089] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In addition, all directional indications (such as up, down, left, right, front, back, bottom, etc.) in this application are only used to explain the relative positional relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly. Further, the descriptions involving "first", "second", etc. in the application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features.

[0090] Embodiment 1

[0091] As Figure 2 , Figure 3 , Figure 4 shown, this embodiment provides a wafer electroplating process treatment device for improving the bonding strength between composite coatings. The process treatment device includes a sealed treatment chamber 1. The sealed treatment chamber 1 includes four sealed small chambers, and the four sealed small chambers include three electroplating chambers and one pickling chamber 7, which are respectively used to perform the process steps of copper plating and spin drying, pickling, nickel plating and spin drying, pickling, and gold plating and spin drying in sequence within the sealed treatment chamber 1. The sealed treatment chamber 1 is connected to a first vacuum pumping device, and the first vacuum pumping device can keep the sealed treatment chamber 1 in a primary vacuum state, thereby reducing the oxidation time and oxidation degree during the compact transfer of wafers. The sealed small chamber is connected to a second vacuum pumping device, and the second vacuum pumping device can keep the sealed small chamber in a secondary vacuum state, which can reduce the oxidation degree of the wafers during electroplating and pickling. The pressure range of the primary vacuum state is -200 to -800 Pa, and the pressure range of the secondary vacuum state is -5000 to -15000 Pa, where the pressure of the secondary vacuum state is lower than that of the primary vacuum state.

[0092] The three electroplating chambers are respectively used for copper plating, nickel plating and gold plating, namely the copper plating chamber 2, the nickel plating chamber 3 and the gold plating chamber 4. The electroplating chambers are provided with liquid inlets, liquid outlets and overflow outlets, and the liquid inlets, liquid outlets and overflow outlets are all connected to the liquid storage tank 5 storing electroplating solution. During electroplating, the electroplating solution enters the electroplating chamber from the liquid storage tank 5 through the liquid inlet and returns to the liquid storage tank 5 through the overflow outlet, and reciprocates in this way to provide the environment required for wafer electroplating. After electroplating is completed, the electroplating solution can be discharged through the liquid outlet.

[0093] The pickling chamber 7 is used to remove the passivation film formed by oxidation on the wafer surface after Cu plating and Ni plating. As Figure 4 shown, its side wall is provided with a double-port nozzle 10 including an acid nozzle and a water nozzle. The acid nozzle and the water nozzle of the double-port nozzle 10 are respectively connected to the liquid storage tank 11 storing 5% dilute sulfuric acid and ultrapure water (DIW) through pipelines. During pickling, under the control of an alternating cycle pulse process, the double-port nozzle 10 sprays 5% dilute sulfuric acid and ultrapure water on the wafer surface in an alternating cycle, so as to remove the passivation film on the basis of not damaging the flatness of the plated surface.

[0094] In addition, to avoid the risk of oxidation of the wafer during electroplating and pickling and to isolate the air from contacting the electroplating stock solution, elastic sealing structures are provided at the openings of the electroplating chamber and the pickling chamber. Specifically, the electroplating chamber and the pickling chamber are integrally or partially designed in a frustum shape, the edge of the chamber entrance is made of elastic material, and a pre-tightening spring 12 is arranged thereon, thereby forming an elastic sealing structure. When the electroplating head 6 holds the wafer and descends into the pickling chamber or the electroplating chamber for pickling or electroplating, the pre-tightening spring 12 at the chamber entrance is in a compressed state, and the elastic edge of the chamber entrance will also press against the side of the electroplating head 6, thereby making the electroplating chamber and the pickling chamber in a relatively sealed state.

[0095] During actual use, the vacuum pumping device respectively connected to the sealing treatment chamber 1 and the sealing small chamber is turned on to keep the sealing treatment chamber 1 in a first-level vacuum state and several sealing small chambers in a second-level vacuum state. As Figure 2As shown in the figure, in the sealed processing chamber 1, first, the electroplating head 6 holds the wafer and enters the copper plating chamber 2. The copper plating solution is placed in the copper plating chamber 2. The electroplating head 6 drives the wafer to descend so that the surface of the wafer contacts the copper plating solution and rotates for electroplating. After the copper plating layer is deposited on the surface of the wafer, the electroplating is stopped. The electroplating head 6 holds the wafer and ascends to spin-dry it, thereby removing the excess plating solution on the surface of the copper plating layer. Then, the electroplating head 6 holds the copper-plated wafer and quickly transfers it to the pickling chamber 7 for pickling steps to remove the passivation layer formed on the surface of the copper plating layer. Under the control of an alternating cycle pulse process, the double-port nozzle 10 in the pickling chamber 7 alternately sprays 5% dilute sulfuric acid and ultrapure water on the surface of the wafer in an alternating cycle to corrode the passivation layer on its surface without affecting the flatness of the copper plating layer. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternating spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds. Immediately afterwards, the electroplating head 6 holds the pickled wafer and enters the nickel plating chamber 3 for nickel plating, so that a nickel layer is deposited on the surface of the wafer and the excess plating solution is spin-dried. After the nickel plating is completed, the electroplating head 6 holds the wafer and enters the pickling chamber 7 again for pickling. The double-port nozzle 10 on the side wall of the pickling chamber 7 alternately sprays dilute sulfuric acid and ultrapure water on the surface of the nickel-plated wafer to remove the passivation layer formed by oxidation on the surface of the nickel plating layer. The pickling chamber 7 entered after nickel plating is the same pickling chamber as the pickling chamber 7 entered after copper plating. After the second pickling is completed, the electroplating head 6 holds the wafer and transfers it to the gold plating chamber 4 for gold plating and spin-dries the excess gold plating solution on the surface.

[0096] In the above steps, the copper plating chamber 2, the pickling chamber 7, the nickel plating chamber 3, and the gold plating chamber 4 are all in a secondary vacuum state, which can reduce the degree of oxidation of the wafer surface during electroplating and pickling. Moreover, bubbles may appear during the electroplating process, and evacuating the chamber also helps to improve the electroplating quality.

[0097] When the wafer is transferred between the electroplating chamber and the pickling chamber, since the sealed processing chamber 1 is in a primary vacuum state, it can also reduce the degree of oxidation of the wafer during the compact transfer between small chambers.

[0098] Embodiment 2

[0099] As Figure 3 , Figure 4 , Figure 5 shown, this embodiment provides a wafer electroplating process treatment device that can be applied to a production line to improve the bonding strength between composite plating layers. This process treatment device is substantially the same as the process treatment device provided in Embodiment 1. The difference is that Embodiment 1 only includes 1 pickling chamber, that is, the pickling chamber 7 entered after copper plating is the same pickling chamber as the pickling chamber 7 entered after nickel plating. In this embodiment, the number of pickling chambers is 2, namely the pickling chamber 8 after copper plating and the pickling chamber 9 after nickel plating. That is, the pickling after copper plating and the pickling after nickel plating are not carried out in the same pickling chamber, but are respectively carried out in two pickling chambers with the same structure.

[0100] When performing large-scale wafer electroplating processing on a production line, it is inevitable to simultaneously perform electroplating pickling on multiple wafers. The sealed treatment chamber 1 in Embodiment 1 only contains one pickling cavity. During the entire composite coating electroplating process, when pickling is required after the nickel plating of the previous wafer is completed, if the next wafer just finishes the copper plating step and also requires pickling at this time, it is difficult for one pickling cavity to simultaneously perform post-copper-plating pickling and post-nickel-plating pickling on multiple wafers, making it difficult to ensure the efficiency and orderliness of electroplating on the production line. Therefore, in this embodiment, two pickling cavities are provided in the sealed treatment chamber, namely, the post-copper-plating pickling cavity 8 and the post-nickel-plating pickling cavity 9, to perform post-copper-plating pickling and post-nickel-plating pickling respectively, which is beneficial to improving the efficiency of large-scale electroplating processing.

[0101] Embodiment 3

[0102] As Figure 6 and Figure 7 shown, this embodiment provides a wafer electroplating process treatment device for improving the bonding strength between composite coatings. The structure of this treatment device is roughly the same as that of the treatment device in Embodiment 1, except that in Embodiment 1, the copper electroplating cavity, the nickel electroplating cavity, and the pickling cavity are three independent sealed small chambers, while in this embodiment, the copper electroplating cavity and the pickling cavity, and the nickel electroplating cavity and the pickling cavity are respectively integrated into one sealed small chamber. Specifically, as Figure 8 shown, the sealed treatment chamber 1 includes two integrated electroplating pickling cavities, namely, the Cu integrated electroplating pickling cavity 15 and the Ni integrated electroplating pickling cavity 16, and also includes a gold plating cavity 4 as described in Embodiment 1. The integrated electroplating pickling cavity is used to integrate the electroplating and pickling steps in one chamber, avoiding the possible oxidation risk when the wafer is transferred between the electroplating cavity and the pickling cavity.

[0103] The integrated electroplating pickling cavity includes, from bottom to top in the vertical direction, a mutually connected electroplating area, a cleaning area, and a pickling area. In actual use, the wafer is clamped by the electroplating head 6 and enters the electroplating area, the cleaning area, and the pickling area respectively to perform electroplating process, cleaning process, and pickling process respectively.

[0104] As Figure 6As shown in the figure, for the electroplating area located below, the electroplating area is provided with a liquid inlet, a liquid outlet, and an overflow port. The liquid inlet, the liquid outlet, and the overflow port are all used to communicate with the liquid storage tank 5 storing the electroplating solution. During electroplating, the electroplating solution flows from the liquid storage tank 5, enters the electroplating area through the liquid inlet, and overflows back to the liquid storage tank 5 through the overflow drain 7 set slightly higher than the free surface of the electroplating solution, thus reciprocating to provide the environment required for wafer electroplating. After electroplating is completed, the electroplating solution in the electroplating area is discharged through the liquid outlet and recovered by the liquid storage tank 5. Since the electroplating area, the cleaning area, and the pickling area are arranged in the same chamber and share a liquid outlet, a three-way valve 17 is provided at the liquid outlet. The three-way valve 17 is provided with a waste liquid valve port and an electroplating solution valve port to switch when discharging the waste liquid formed in different areas. When electroplating is completed, the electroplating solution valve port 19 of the three-way valve 17 is opened, and the electroplating solution is discharged through this port.

[0105] Furthermore, as Figure 6 shown, the bottom inner wall of the electroplating area slopes towards the center to form an inverted cone, which is beneficial to having no dead corners of residual liquid when discharging liquid from the chamber and avoiding liquid accumulation residue.

[0106] For the cleaning area located above the electroplating area, it is used to realize the function of self-cleaning the chamber with ultrapure water + N2 after the electroplating step. The cleaning area is provided with a number of fan-shaped nozzles 20, and the fan-shaped nozzles 20 are symmetrically arranged around the inner wall of the chamber. For example, 6 are symmetrically arranged, with each separated by 60 degrees. Each nozzle sprays fan-shaped mist of ultrapure water obliquely downward to cover at least 65 degrees of the inner wall of the chamber, so that there is no dead corner in the self-cleaning process. When the wafer completes the electroplating step in the electroplating area, the electroplating solution waste liquid is discharged through the liquid outlet. At the same time, the electroplating head 6 is lifted to the cleaning area, and the electroplating head 6 is controlled to rotate to throw off the remaining electroplating solution. Then the fan-shaped nozzles 20 start to work, spraying ultrapure water into the chamber to clean the chamber. After cleaning is completed, the fan-shaped nozzles 20 spray N2 to dry the chamber.

[0107] Regarding the pickling area located above the cleaning area, double-nozzle 10 including an acid nozzle and a water nozzle is provided on the side wall of the pickling area. The acid nozzle and the water nozzle of the double-nozzle 10 are respectively connected to a liquid storage tank 11 storing 5% dilute sulfuric acid and ultrapure water through a conduit. During pickling, under the control of an alternating cycle pulse process, the double-nozzle 10 alternately sprays dilute sulfuric acid and ultrapure water on the wafer surface in an alternating cycle. Among them, the dilute sulfuric acid and the ultrapure water are alternately sprayed 1-6 times. Each time of alternating spraying, the pickling time is 5-20 seconds, and the ultrapure water washing time is 10-40 seconds, so as to eliminate the passivation film without damaging the flatness of the plating surface. In addition, a reflux tank 13 is provided in the pickling area. The reflux tank 13 is integrally a hollow ring arranged along the inner wall of the cavity. One end of it is connected to the side cavity wall of the chamber, and the upper part of the other end extends upward to form a groove part between it and the side cavity wall of the pickling area. Its hollow part forms a channel for the plating head 6 to move up and down between the electroplating area, the cleaning area and the pickling area in the vertical direction. The reflux tank 13 is used to collect the pickling waste liquid splashed out during the wafer pickling process. In addition, a reflux tank return port 14 is also included on the side wall of the pickling area, which is used to discharge the pickling waste liquid collected by the reflux tank 13.

[0108] To avoid the risk of oxidation during wafer electroplating, cleaning and pickling, and to isolate air from contacting the electroplating stock solution, the pickling area as a whole or its upper part adopts a frustum shape design. A chamber entrance is provided at the top of the frustum. The edge of the chamber entrance is made of an elastic material, and a pre-tightening spring 12 is provided thereon, thereby forming an elastic sealing structure. Corresponding to the design of the chamber entrance, when the wafer is in the pickling process state, the position on the plating head 6 flush with the chamber entrance is defined as the pickling position. The dimensions of the pickling position of the plating head 6 and the positions above it are larger than the dimensions of the chamber entrance in the natural state, and the positions below it are smaller than the dimensions of the chamber entrance in the natural state. Since in the electroplating and pickling process states of the wafer, the entry depth of the plating head 6 into the chamber entrance is in the order of electroplating > pickling, this means that during the whole process of the wafer being clamped by the plating head 6 and passing through the chamber entrance into the chamber for electroplating process and pickling process, the elastic sealing structure will press the side of the plating head 6, thereby making the integrated electroplating and pickling chamber in a relatively sealed state.

[0109] The integrated electroplating and pickling chamber is used for electroplating and pickling of Cu and Ni. Since the electroplating and pickling steps are located in the same chamber, compared with Embodiment 1 and 2, the process of the plating head clamping the wafer and transferring it between the electroplating chamber and the pickling chamber is reduced. Therefore, the oxidation degree of Cu and Ni during electroplating and pickling is effectively reduced. Since gold element is relatively stable and not easily oxidized by air, there is no need for a pickling step after gold plating. Therefore, gold plating only needs to be carried out in a sealed ordinary chamber, rather than in the above integrated electroplating and pickling chamber.

[0110] When the wafer electroplating process treatment equipment for improving the bonding strength between composite coatings provided in this embodiment is actually applied, first, the vacuum pumping device connected to the sealed treatment chamber 1 and the sealed small chamber (integrated electroplating pickling chamber and gold electroplating chamber) is turned on to keep the sealed treatment chamber 1 in a first-level vacuum state and several sealed small chambers in a second-level vacuum state. The pressure range of the first-level vacuum state is -200 to -800 Pa, and the pressure range of the second-level vacuum state is -5000 to -15000 Pa, where the pressure of the second-level vacuum state is lower than that of the first-level vacuum state. Then, the electroplating process is started. Specifically, first, the electroplating head 6 holds the wafer and enters the chamber from the chamber entrance of the Cu integrated electroplating pickling chamber 15 and descends to the electroplating area. During this process, the elastic sealing structure at the chamber entrance presses against the outer wall of the electroplating head 6 to achieve sealing. After the electroplating head 6 holds the wafer and descends until the wafer touches the free surface of the Cu electroplating solution, the electroplating head 6 drives the wafer to rotate and starts wafer electroplating. After the Cu electroplating is completed, the electroplating head 6 rises to the cleaning area. At the same time, the liquid outlet is opened to drain the electroplating solution in the electroplating area. Then, the electroplating head 6 is controlled to rotate to throw off the residual electroplating solution on its surface. Furthermore, the sector nozzle 20 in the cleaning area is opened, and the sector nozzle 20 sprays ultrapure water to clean the Cu integrated electroplating pickling chamber 15 and is dried with nitrogen. After the cleaning waste liquid is discharged through the liquid outlet, the electroplating solution valve port 19 of the three-way valve 17 is closed. After the cleaning is completed, the electroplating head 6 rises to the pickling area, the waste liquid valve port 18 of the three-way valve is opened, and then the double-port nozzle 10 is controlled to alternately spray 5% H2SO4 and ultrapure water for the pickling step of the wafer surface. After the pickling is completed, the sector nozzle 20 is opened for ultrapure water jet rinsing and nitrogen purging to achieve chamber cleaning. After the chamber cleaning is completed, the electroplating head 6 is removed from the Cu integrated electroplating pickling chamber and the entire three-way valve 17 is closed. Thus, the entire electroplating and pickling process of Cu is completed in one chamber. Then, the plating head holds the wafer and enters the Ni integrated electroplating pickling chamber 16, and the above process is repeated to complete the electroplating of Ni and the pickling process of the surface passivation film. Finally, the electroplating head 6 holds the wafer that has been copper-plated and nickel-plated and enters the gold electroplating chamber as described in Embodiment 1 for the gold plating step.

[0111] It should be noted that since gold is relatively stable and not easily oxidized, in other embodiments of the present invention, based on the design of Embodiment 1 or Embodiment 2 or Embodiment 3, the gold electroplating chamber can be adjusted as follows: The gold electroplating chamber 4 is not evacuated, and a common chamber design is adopted to save costs (that is, it can be not connected to the second vacuum pumping device, and an elastic sealing structure can also be not designed for sealing).

[0112] Further, during the gold plating process, since the transfer speed of the electroplating head 6 clamping the wafer from the pickling chamber / pickling area to the gold plating chamber 4 is relatively rapid, and the gold element is relatively stable and not easily oxidized, in other embodiments of the present invention, on the basis of adopting the design of Embodiment 1 or Embodiment 2 or Embodiment 3, the following adjustments can be made to the gold plating chamber: Design the gold plating chamber 4 to be placed outside the sealed treatment chamber 1.

[0113] Embodiment 4:

[0114] As Figure 8 shown, this embodiment provides an electroplating process for improving the bonding strength between composite coatings. The wafer electroplating process treatment equipment for improving the bonding strength between composite coatings described in Embodiment 1 is adopted. In this equipment, the gold plating chamber is located inside the sealed treatment chamber. This embodiment mainly includes the following steps: plating copper and spin-drying in the copper plating chamber, pickling in the pickling chamber, plating nickel and spin-drying in the nickel plating chamber, performing a second pickling in the same pickling chamber, plating gold and spin-drying in the gold plating chamber, etc. Specifically, it includes the following steps:

[0115] S1. Water washing (vacuum pre-wetting): First, place the wafer to be processed under vacuum conditions for cleaning and removing surface impurities such as oxides to ensure the smooth progress of the subsequent electroplating process.

[0116] S2. Mask preparation: Coat a special photoresist on the area of the wafer surface that needs to be protected, and then prepare a mask pattern through a photolithography process to control the position and shape of metal deposition.

[0117] S3. Electroplating bath modulation: Select the corresponding electroplating bath according to the metal material to be deposited, and adjust it to appropriate process parameters, including the composition, concentration, temperature, stirring speed, etc. of the electrolyte.

[0118] S4. Vacuum pumping: Turn on the first vacuum pumping device and the second vacuum pumping device to perform vacuum pumping on the sealed treatment chamber and the sealed small chamber, so that the sealed treatment chamber maintains a primary vacuum state, and the sealed small chamber maintains a secondary vacuum state. The pressure range of the primary vacuum state is -200 to -800 Pa, and the pressure range of the secondary vacuum state is -5000 to -15000 Pa, where the pressure of the secondary vacuum state is lower than that of the primary vacuum state.

[0119] S5. Plating copper and spin-drying: Move the wafer prepared with the mask into the copper plating chamber in the sealed treatment chamber through the electroplating head. The electroplating head clamps the wafer and descends to contact the free surface of the electroplating solution and rotates. By applying an electric field and current, deposit metal Cu on the wafer surface. After electroplating, the electroplating head rises and starts to rotate to spin-dry the residual electroplating solution on the wafer. The electroplating head clamps the wafer and rises away from the copper plating chamber and quickly transfers it to the pickling chamber.

[0120] S6, Pickling, Cleaning, and Drying: The electroplating head quickly transfers the wafer that has completed copper electroplating into the pickling chamber for the pickling step. The dual-nozzle sprays dilute sulfuric acid with a concentration of 5% and ultrapure water onto the wafer surface alternately under the control of the pulse process. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternate spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds. After pickling, the electroplating head drives the wafer to rotate and dry. Subsequently, the residual waste liquid on the wafer surface at this time is thoroughly cleaned and dried with ultrapure water. Then, the electroplating head drives the wafer to rise and leave the pickling chamber and quickly transfers it to the nickel plating chamber;

[0121] S7, Nickel Plating and Drying: The electroplating head drives the wafer to descend until it contacts the free surface of the electroplating solution and rotates under the drive of the electroplating head. By applying an electric field and current, metallic nickel is deposited on the wafer surface. After electroplating, the electroplating head rises and rotates to dry the residual electroplating solution on the wafer. The electroplating head holds the wafer and rises to leave the nickel plating chamber and quickly transfers it to the pickling chamber.

[0122] S8, Pickling, Cleaning, and Drying: After the wafer is nickel-plated, the electroplating head quickly transfers the wafer that has completed nickel electroplating into the pickling chamber for the pickling step. The dual-nozzle sprays dilute sulfuric acid with a concentration of 5% and ultrapure water onto the wafer surface alternately under the control of the pulse process. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternate spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds. After pickling, the electroplating head drives the wafer to rotate and dry. Subsequently, the residual waste liquid on the wafer surface at this time is thoroughly cleaned and dried with ultrapure water. The electroplating head holds the wafer and rises to leave the pickling chamber and quickly transfers it to the gold plating chamber.

[0123] S9, Gold Plating and Drying: The electroplating head drives the wafer to descend until it contacts the free surface of the electroplating solution and rotates under the drive of the electroplating head. By applying an electric field and current, gold is deposited on the wafer surface. After electroplating, the electroplating head rises and rotates to dry the residual electroplating solution on the wafer. The electroplating head holds the gold-plated wafer and leaves the gold plating chamber and the sealed processing chamber.

[0124] S10, Cleaning: Transfer the gold-plated wafer to the cleaning chamber to clean the wafer surface.

[0125] S11, Detection and Analysis: Detect and analyze the surface morphology, film thickness, structure, etc. of the electroplated wafer to ensure the stability of the electroplating process and the film layer quality.

[0126] S12, Post-treatment: According to requirements, perform other treatments on the electroplated wafer, such as heat treatment, annealing, corrosion, etc., to further improve the film layer performance or prepare special structures.

[0127] In other embodiments, for efficiency considerations, the user may also adopt two pickling chambers, and perform pickling after copper plating and pickling after nickel plating in these two pickling chambers respectively.

[0128] Embodiment 5

[0129] As Figure 9 shown, this embodiment provides an electroplating process for improving the bonding strength between composite coatings. The wafer electroplating process treatment equipment used in this electroplating process is adjusted as follows based on Embodiment 1: The gold plating chamber is arranged outside the sealed treatment chamber. This electroplating process mainly includes the following steps: plating copper and spin-drying in the copper plating chamber, pickling in the pickling chamber, plating nickel and spin-drying in the nickel plating chamber, performing a second pickling in the same pickling chamber, plating gold and spin-drying in the gold plating chamber, etc. Specifically, it includes the following steps:

[0130] S1. Water washing (vacuum pre-wetting): First, place the wafer to be processed under vacuum conditions for cleaning and removing surface impurities such as oxides to ensure the smooth progress of the subsequent electroplating process.

[0131] S2. Mask preparation: Coat a special photoresist on the area of the wafer surface that needs to be protected, and then prepare a mask pattern through a lithography process to control the position and shape of metal deposition.

[0132] S3. Electroplating bath modulation: Select the corresponding electroplating bath according to the metal material to be deposited, and adjust it to appropriate process parameters, including the composition, concentration, temperature, stirring speed, etc. of the electrolyte.

[0133] S4. Vacuum pumping: Turn on the first vacuum pumping device and the second vacuum pumping device to perform vacuum pumping on the sealed treatment chamber and the sealed small chamber, so that the sealed treatment chamber maintains a primary vacuum state and the sealed small chamber maintains a secondary vacuum state. The pressure range of the primary vacuum state is -200 to -800 Pa, and the pressure range of the secondary vacuum state is -5000 to -15000 Pa, where the pressure of the secondary vacuum state is lower than that of the primary vacuum state.

[0134] S5. Copper plating and spin-drying: Move the wafer prepared with the mask into the copper plating chamber in the sealed treatment chamber through the electroplating head. The electroplating head holds the wafer and descends to contact the free surface of the electroplating solution and rotates. By applying an electric field and current, deposit metal Cu on the wafer surface. After electroplating, the electroplating head rises and starts to rotate to spin-dry the residual electroplating solution on the wafer. The electroplating head holds the wafer and rises to leave the copper plating chamber and quickly transfers it to the pickling chamber.

[0135] S6, Pickling, Cleaning, and Drying: The electroplating head quickly transfers the wafer that has completed copper electroplating into the pickling chamber for the pickling step. The dual-port nozzle alternately sprays dilute sulfuric acid with a concentration of 5% and ultrapure water onto the wafer surface under the control of a pulse process. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternate spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds. After pickling, the electroplating head drives the wafer to rotate and dry. Subsequently, the residual waste liquid on the wafer surface at this time is thoroughly cleaned and dried with ultrapure water. Then, the electroplating head drives the wafer to rise and leave the pickling chamber and quickly transfers it to the nickel plating chamber;

[0136] S7, Nickel Plating and Drying: The electroplating head drives the wafer to descend until it contacts the free surface of the electroplating solution and rotates under the drive of the electroplating head. By applying an electric field and current, metallic nickel is deposited on the wafer surface. After electroplating, the electroplating head rises and rotates to dry the residual electroplating solution on the wafer. The electroplating head holds the wafer and rises to leave the nickel plating chamber and quickly transfers it to the pickling chamber.

[0137] S8, Pickling, Cleaning, and Drying: After the wafer is nickel-plated, the electroplating head quickly transfers the wafer that has completed nickel electroplating into the pickling chamber for the pickling step. The dual-port nozzle alternately sprays dilute sulfuric acid with a concentration of 5% and ultrapure water onto the wafer surface under the control of a pulse process. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternate spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds. After pickling, the electroplating head drives the wafer to rotate and dry. Subsequently, the residual waste liquid on the wafer surface at this time is thoroughly cleaned and dried with ultrapure water. The electroplating head holds the wafer and rises to leave the pickling chamber. At the same time, the electroplating head drives the wafer to leave the sealing treatment chamber and quickly transfers it to the gold plating chamber.

[0138] S9, Gold Plating and Drying: The electroplating head drives the wafer to descend until it contacts the free surface of the electroplating solution and rotates under the drive of the electroplating head. By applying an electric field and current, gold is deposited on the wafer surface. After electroplating, the electroplating head rises and rotates to dry the residual electroplating solution on the wafer. The electroplating head holds the wafer after gold plating and leaves the gold plating chamber.

[0139] S10, Cleaning: Transfer the wafer after gold plating to the cleaning chamber to clean the wafer surface.

[0140] S11, Detection and Analysis: Detect and analyze the surface morphology, film thickness, structure, etc. of the electroplated wafer to ensure the stability of the electroplating process and the film layer quality.

[0141] S12, Post-treatment: According to requirements, perform other treatments on the electroplated wafer, such as heat treatment, annealing, corrosion, etc., to further improve the film layer performance or prepare special structures.

[0142] In other embodiments, for efficiency considerations, the user can also adopt two pickling chambers, and perform pickling after copper plating and pickling after nickel plating in these two pickling chambers respectively.

[0143] Embodiment 6

[0144] As Figure 10 shown, this embodiment provides an electroplating process for improving the bonding strength between composite coatings. The wafer electroplating process equipment for improving the bonding strength between composite coatings described in Embodiment 3 is adopted. In this equipment, the gold plating chamber is located inside the sealed processing chamber.

[0145] This embodiment generally mainly includes the following steps: plating copper and pickling in the Cu integrated electroplating pickling chamber, plating nickel and pickling in the Ni integrated electroplating pickling chamber, plating gold and spin-drying in the gold plating chamber, etc. Specifically, it includes the following steps:

[0146] S1. Water washing (vacuum pre-wetting): First, place the wafer to be processed under vacuum conditions for cleaning and removing surface impurities such as oxides to ensure the smooth progress of the subsequent electroplating process.

[0147] S2. Mask preparation: Coat a special photoresist on the area of the wafer surface that needs to be protected, and then prepare a mask pattern through a photolithography process to control the position and shape of metal deposition.

[0148] S3. Electroplating bath modulation: Select the corresponding electroplating bath according to the metal material to be deposited, and modulate it to appropriate process parameters, including the composition, concentration, temperature, stirring speed, etc. of the electrolyte.

[0149] S4. Vacuum pumping: Turn on the first vacuum pumping device and the second vacuum pumping device to perform vacuum pumping on the sealed processing chamber and the integrated electroplating pickling chamber, so that the sealed processing chamber maintains a primary vacuum state, and the integrated electroplating pickling chamber maintains a secondary vacuum state; wherein the pressure range of the primary vacuum state is -200 to -800 Pa, and the pressure range of the secondary vacuum state is -5000 to -15000 Pa, and the pressure of the secondary vacuum state is lower than that of the primary vacuum state.

[0150] S5. Copper plating and pickling: The electroplating head holds the wafer and enters the Cu integrated electroplating and pickling chamber in the sealed processing chamber, then descends to the electroplating area to start wafer electroplating. After the Cu electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, the sector nozzles in the cleaning area are opened to spray ultrapure water to clean the integrated electroplating and pickling chamber, and then it is dried with nitrogen. Then, it drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without passing through the cleaning of the integrated electroplating and pickling chamber as needed. The double-port nozzle is controlled to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times, and the pickling time is 5 - 20 seconds each time during the alternate spraying, and the ultrapure water washing time is 10 - 40 seconds. After pickling is completed, the sector nozzles in the cleaning area are opened again for chamber cleaning. Subsequently, the electroplating head drives the wafer out of the Cu integrated electroplating and pickling chamber;

[0151] S6. Nickel plating and pickling: The electroplating head holds the wafer and enters the Ni integrated electroplating and pickling chamber, then descends to the electroplating area to start wafer electroplating. After the Ni electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, the sector nozzles in the cleaning area are opened to spray ultrapure water to clean the integrated electroplating and pickling chamber, and then it is dried with nitrogen. Then, it drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without passing through the cleaning of the integrated electroplating and pickling chamber as needed. The double-port nozzle is controlled to alternately spray 5% dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times, and the pickling time is 5 - 20 seconds each time during the alternate spraying, and the ultrapure water washing time is 10 - 40 seconds. After pickling is completed, the sector nozzles in the cleaning area are opened again for chamber cleaning. Subsequently, the electroplating head drives the wafer out of the Ni integrated electroplating and pickling chamber;

[0152] S7. Gold plating and spin-drying: The electroplating head holds the wafer and enters the gold plating chamber, then descends to contact the free surface of the electroplating solution. By applying an electric field and current, gold is deposited on the wafer surface. After electroplating is completed, the electroplating head rises and rotates to spin-dry the residual electroplating solution on the wafer. Subsequently, the electroplating head holds the wafer and rises out of the gold plating chamber and the sealed processing chamber;

[0153] S8. Cleaning: Transfer the wafer after gold plating to the cleaning chamber to clean the wafer surface.

[0154] S9. Detection and analysis: Detect and analyze the surface morphology, film thickness, structure, etc. of the electroplated wafer to ensure the stability of the electroplating process and the film layer quality.

[0155] S10. Post-treatment: According to needs, perform other treatments on the electroplated wafer, such as heat treatment, annealing, corrosion, etc., to further improve the film layer performance or prepare special structures.

[0156] Example 7

[0157] As Figure 11 shown, this embodiment provides an electroplating process for improving the bonding strength between composite coatings. The wafer electroplating process equipment used in this electroplating process is adjusted as follows based on the equipment in Embodiment 3: The gold plating chamber is arranged outside the sealed treatment chamber. Generally, this embodiment includes the following steps: plating copper and pickling in the Cu integrated electroplating pickling chamber, plating nickel and pickling in the Ni integrated electroplating pickling chamber, plating gold and spin-drying in the gold plating chamber, etc. Specifically, it includes the following steps:

[0158] S1. Water washing (vacuum pre-wetting): First, place the wafer to be processed under vacuum conditions for cleaning and removing surface impurities such as oxides to ensure the smooth progress of the subsequent electroplating process.

[0159] S2. Mask preparation: Coat a special photoresist on the area of the wafer surface that needs to be protected, and then prepare a mask pattern through a photolithography process to control the position and shape of metal deposition.

[0160] S3. Electroplating bath modulation: Select the corresponding electroplating bath according to the metal material to be deposited, and adjust it to appropriate process parameters, including the composition, concentration, temperature, stirring speed, etc. of the electrolyte.

[0161] S4. Vacuum pumping: Turn on the first vacuum pumping device and the second vacuum pumping device to perform vacuum pumping on the sealed treatment chamber and the integrated electroplating pickling chamber, so that the sealed treatment chamber maintains a primary vacuum state, and the integrated electroplating pickling chamber maintains a secondary vacuum state. The pressure range of the primary vacuum state is -200 to -800 Pa, and the pressure range of the secondary vacuum state is -5000 to -15000 Pa, where the pressure of the secondary vacuum state is lower than that of the primary vacuum state.

[0162] S5. Copper plating and pickling: The electroplating head holds the wafer and enters the Cu integrated electroplating pickling chamber and descends to the electroplating area to start wafer electroplating. After the Cu electroplating is completed, the electroplating head drives the wafer to rise and spin-dry; after spin-drying, open the fan-shaped nozzle in the cleaning area to spray ultrapure water to clean the integrated electroplating pickling chamber, and blow it dry with nitrogen, and then drive the wafer to rise to the pickling area, or directly control the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating pickling chamber according to needs, and control the double-port nozzle to alternately spray 5% dilute sulfuric acid and ultrapure water for the pickling step of the wafer surface. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times, and the pickling time is 5 - 20 seconds each time during the alternate spraying, and the ultrapure water washing time is 10 - 40 seconds. After pickling, open the fan-shaped nozzle in the cleaning area again for chamber cleaning; then, the electroplating head drives the wafer out of the Cu integrated electroplating pickling chamber;

[0163] S6, Nickel Plating and Pickling: The electroplating head holds the wafer and enters the Ni integrated electroplating and pickling chamber, then descends to the electroplating area to start wafer electroplating. After Ni electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, the sector nozzles in the cleaning area are opened to spray ultrapure water to clean the integrated electroplating and pickling chamber, and then blow-dry with nitrogen. Then, it drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without passing through the integrated electroplating and pickling chamber according to needs. Control the double-port nozzle to alternately spray 5% dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. Among them, the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times, and the pickling time is 5 - 20 seconds each time during alternate spraying, and the ultrapure water washing time is 10 - 40 seconds. After pickling is completed, the sector nozzles in the cleaning area are opened again for chamber cleaning; Subsequently, the electroplating head drives the wafer to sequentially move out of the Ni integrated electroplating and pickling chamber and the sealing treatment chamber;

[0164] S7, Gold Plating and Spin-Drying: The electroplating head holds the wafer and enters the gold plating chamber located outside the sealing treatment chamber, then descends to contact the free surface of the electroplating solution, and deposits gold on the wafer surface by applying an electric field and current. After electroplating is completed, the electroplating head rises and rotates to spin-dry the residual electroplating solution on the wafer. Subsequently, the electroplating head holds the wafer and rises away from the gold plating chamber.

[0165] S8, Cleaning: Transfer the wafer after gold plating to the cleaning chamber to clean the wafer surface.

[0166] S9, Detection and Analysis: Detect and analyze the surface morphology, film thickness, structure, etc. of the electroplated wafer to ensure the stability of the electroplating process and the film layer quality.

[0167] S10, Post-Treatment: According to needs, perform other treatments on the electroplated wafer, such as heat treatment, annealing, corrosion, etc., to further improve the film layer performance or prepare special structures.

[0168] The specific embodiments of the present invention have been described above. Through the above description, relevant staff can make various changes and modifications completely within the scope of not deviating from the technical idea of this invention.

Claims

1. A wafer electroplating process treatment device for improving the bonding strength between composite coatings, characterized in that, it includes a sealed treatment chamber, and the sealed treatment chamber includes several sealed small chambers. The sealed small chambers are composed of an electroplating chamber and a pickling chamber. The electroplating chamber is used for electroplating, and the pickling chamber is used for pickling; the sealed treatment chamber is connected to a first vacuum pumping device, and the first vacuum pumping device can keep the inside of the sealed treatment chamber in a first-level vacuum state. The sealed small chamber is connected to a second vacuum pumping device, and the second vacuum pumping device can keep the inside of the sealed small chamber in a second-level vacuum state; an elastic sealing structure is arranged at the chamber entrance of the sealed small chamber. When the electroplating head holds the wafer and descends into the sealed small chamber for pickling or electroplating, the elastic sealing structure at the chamber entrance presses against the side of the electroplating head; a double-port nozzle including an acid nozzle and a water nozzle is arranged on the side wall of the pickling chamber. The acid nozzle is connected to a dilute sulfuric acid storage tank, and the water nozzle is connected to an ultrapure water storage tank. The double-port nozzle alternately sprays dilute sulfuric acid and ultrapure water onto the wafer surface under the control of a pulse process.

2. The wafer electroplating process treatment device for improving the bonding strength between composite coatings according to claim 1, characterized in that, two electroplating chambers and one or two pickling chambers are arranged in the sealed treatment chamber; the two electroplating chambers are a copper plating chamber and a nickel plating chamber respectively.

3. The wafer electroplating process treatment device for improving the bonding strength between composite coatings according to claim 2, characterized in that, a gold plating chamber is also arranged in the sealed treatment chamber.

4. A wafer electroplating process treatment device for improving the bonding strength between composite coatings, characterized in that, it includes a sealed treatment chamber, and the sealed treatment chamber includes several integrated electroplating and pickling chambers; the sealed treatment chamber is connected to a first vacuum pumping device, and the first vacuum pumping device can keep the inside of the sealed treatment chamber in a first-level vacuum state. The integrated electroplating and pickling chamber is connected to a second vacuum pumping device, and the second vacuum pumping device can keep the inside of the integrated electroplating and pickling chamber in a second-level vacuum state; the integrated electroplating and pickling chamber includes, from bottom to top in the vertical direction, a connected electroplating area, a cleaning area, and a pickling area. The electroplating area, the cleaning area, and the pickling area are respectively used for electroplating process, cleaning process, and pickling process; a chamber entrance is arranged at the top of the pickling area, and an elastic sealing structure is arranged at the chamber entrance. When the electroplating head holds the wafer and descends into the integrated electroplating and pickling chamber for pickling, cleaning, or electroplating, the elastic sealing structure at the chamber entrance presses against the side of the electroplating head; a double-port nozzle including an acid nozzle and a water nozzle is arranged on the side wall of the pickling area. The acid nozzle is connected to a dilute sulfuric acid storage tank, and the water nozzle is connected to an ultrapure water storage tank. The double-port nozzle alternately sprays dilute sulfuric acid and ultrapure water onto the wafer surface under the control of a pulse process; the cleaning area includes several fan-shaped nozzles, and the fan-shaped nozzles are used for spraying ultrapure water for cleaning.

5. The wafer electroplating process treatment device for improving the bonding strength between composite coatings according to claim 4, characterized in that, The electroplating area is provided with a liquid inlet, a liquid outlet and an overflow port, and the liquid inlet, the liquid outlet and the overflow port are all communicated with a liquid storage tank storing electroplating solution; a three-way valve is arranged at the liquid outlet, and the three-way valve is provided with an electroplating solution valve port and a waste liquid valve port; the inner wall of the bottom of the electroplating area inclines towards the center to form an inverted cone shape.

6. The wafer electroplating process treatment equipment for improving the bonding force between composite coatings according to claim 4, characterized in that, a reflux tank and a reflux tank return port are further arranged on the side wall of the pickling area; the reflux tank is integrally a hollow ring arranged along the inner wall of the pickling area cavity, one end of which is connected with the side cavity wall of the pickling area, and the upper part of the other end extends upwards to form a groove part with the side cavity wall of the pickling area for collecting pickling waste liquid splashed out during the pickling process; the reflux tank return port is used for discharging the pickling waste liquid collected by the reflux tank.

7. The wafer electroplating process treatment equipment for improving the bonding force between composite coatings according to claim 4, characterized in that, a gold plating cavity is further included in the sealing treatment chamber.

8. The wafer electroplating process treatment equipment for improving the bonding force between composite coatings according to claim 1 or 4, characterized in that, the pressure range of the first-level vacuum state is -200 to -800 Pa, and the pressure range of the second-level vacuum state is -5000 to -15000 Pa, wherein the pressure of the second-level vacuum state is lower than that of the first-level vacuum state.

9. The wafer electroplating process treatment equipment for improving the bonding force between composite coatings according to claim 1 or 4, characterized in that, the concentration of the dilute sulfuric acid is 5%.

10. An electroplating process for improving the bonding force between composite coatings, including copper electroplating, nickel electroplating and gold electroplating, characterized in that, using the wafer electroplating process treatment equipment for improving the bonding force between composite coatings according to claim 1 to perform copper electroplating and nickel electroplating in sequence, including the following steps: S10. Vacuum pumping: Perform vacuum pumping on the sealing treatment chamber and the sealing small chamber to keep the sealing treatment chamber in the first-level vacuum state and the sealing small chamber in the second-level vacuum state; S20. Copper plating and spin-drying: Move the wafer into the copper plating cavity through the electroplating head to deposit metal Cu on the surface of the wafer. After the copper electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then, the electroplating head drives the wafer to rise and leave the copper plating cavity; S30. Pickling and spin-drying: Quickly transfer the wafer completed with copper electroplating into the pickling cavity through the electroplating head for pickling steps, so that the double-nozzle sprays dilute sulfuric acid and ultrapure water on the surface of the wafer alternately under the control of the pulse process. After the pickling is completed, the electroplating head drives the wafer to rotate and spin-dry, and then, the electroplating head drives the wafer to rise and leave the pickling cavity; S40. Nickel plating and spin-drying: Move the wafer into the nickel plating cavity through the electroplating head to deposit metal Ni on the surface of the wafer. After the nickel electroplating is completed, the electroplating head drives the wafer to rise and spin-dry, and then, the electroplating head drives the wafer to rise and leave the nickel plating cavity; S50, Pickling and spin-drying: The wafer that has completed nickel electroplating is quickly transferred into the pickling chamber by the electroplating head for pickling. The dual-nozzle sprays dilute sulfuric acid and ultrapure water onto the wafer surface alternately under the control of the pulse process. After pickling, the electroplating head drives the wafer to rotate and spin-dry. Then, the electroplating head drives the wafer to rise and leave the pickling chamber; then, the electroplating head drives the wafer to leave the sealed processing chamber; S60, Gold plating and spin-drying: The wafer is transferred into the gold plating chamber outside the sealed processing chamber by the electroplating head to deposit metal Au on the wafer surface. After gold electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber; S70, Cleaning: The wafer after gold plating is transferred into the cleaning chamber by the electroplating head for cleaning the wafer surface.

11. An electroplating process for improving the bonding strength between composite coatings, characterized in that, using the wafer electroplating process treatment equipment for improving the bonding strength between composite coatings described in claim 3 to perform copper electroplating, nickel electroplating and gold electroplating in sequence, including the following steps: S10, Vacuum pumping: The sealed processing chamber and the sealed small chamber are vacuum pumped so that the sealed processing chamber maintains a primary vacuum state and the sealed small chamber maintains a secondary vacuum state; S20, Copper plating and spin-drying: The wafer is transferred into the copper plating chamber by the electroplating head to deposit metal Cu on the wafer surface. After copper electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. Then, the electroplating head drives the wafer to rise and leave the copper plating chamber; S30, Pickling and spin-drying: The wafer that has completed copper electroplating is quickly transferred into the pickling chamber by the electroplating head for pickling. The dual-nozzle sprays dilute sulfuric acid and ultrapure water onto the wafer surface alternately under the control of the pulse process. After pickling, the electroplating head drives the wafer to rotate and spin-dry. Then, the electroplating head drives the wafer to rise and leave the pickling chamber; S40, Nickel plating and spin-drying: The wafer is transferred into the nickel plating chamber by the electroplating head to deposit metal Ni on the wafer surface. After nickel electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. Then, the electroplating head drives the wafer to rise and leave the nickel plating chamber; S50, Pickling and spin-drying: The wafer that has completed nickel electroplating is quickly transferred into the pickling chamber by the electroplating head for pickling. The dual-nozzle sprays dilute sulfuric acid and ultrapure water onto the wafer surface alternately under the control of the pulse process. After pickling, the electroplating head drives the wafer to rotate and spin-dry. Then, the electroplating head drives the wafer to rise and leave the pickling chamber; S60, Gold plating and spin-drying: The wafer is transferred into the gold plating chamber by the electroplating head to deposit metal Au on the wafer surface. After gold electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber; Subsequently, the electroplating head drives the wafer to leave the sealed processing chamber; S70, Cleaning: The wafer after gold plating is transferred into the cleaning chamber by the electroplating head for cleaning the wafer surface.

12. An electroplating process for improving the bonding strength between composite coatings, including copper electroplating, nickel electroplating and gold electroplating, characterized in that, using the wafer electroplating process treatment equipment for improving the bonding strength between composite coatings described in claim 4 to perform copper electroplating and nickel electroplating in sequence, including the following steps: S10. Vacuum the sealed treatment chamber and the integrated electroplating and pickling chamber to keep the sealed treatment chamber in a first-level vacuum state and the integrated electroplating and pickling chamber in a second-level vacuum state; S20. Copper plating and pickling: The electroplating head holds the wafer and enters the Cu integrated electroplating and pickling chamber and descends to the electroplating area to start wafer electroplating. After the Cu electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, open the sector nozzles in the cleaning area to clean the integrated electroplating and pickling chamber and blow it dry with nitrogen. Then, the electroplating head drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating and pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. After pickling is completed, clean the chamber again. Subsequently, the electroplating head drives the wafer out of the Cu integrated electroplating and pickling chamber; S30. Nickel plating and pickling: The electroplating head holds the wafer and enters the Ni integrated electroplating and pickling chamber and descends to the electroplating area to start wafer electroplating. After the Ni electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, open the sector nozzles in the cleaning area to clean the integrated electroplating and pickling chamber and blow it dry with nitrogen. Then, the electroplating head drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating and pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. After pickling is completed, clean the chamber again. Subsequently, the electroplating head drives the wafer out of the Ni integrated electroplating and pickling chamber; Then, the electroplating head drives the wafer out of the sealed treatment chamber; S40. Gold plating and spin-drying: Move the wafer into the gold plating chamber outside the sealed treatment chamber through the electroplating head to deposit metal Au on the wafer surface. After the gold electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber; S50. Cleaning: Move the wafer after gold plating into the cleaning chamber for cleaning the wafer surface through the electroplating head.

13. An electroplating process for improving the bonding strength between composite coatings, including copper electroplating, nickel electroplating, and gold electroplating, characterized in that using the wafer electroplating process treatment equipment for improving the bonding strength between composite coatings described in claim 7 to perform copper electroplating, nickel electroplating, and gold electroplating in sequence, including the following steps: S10. Vacuum the sealed treatment chamber and the integrated electroplating and pickling chamber to keep the sealed treatment chamber in a first-level vacuum state and the integrated electroplating and pickling chamber in a second-level vacuum state; S20. Copper plating and pickling: The electroplating head holds the wafer and enters the Cu integrated electroplating and pickling chamber and descends to the electroplating area to start wafer electroplating. After the Cu electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, open the sector nozzles in the cleaning area to clean the integrated electroplating and pickling chamber and blow it dry with nitrogen. Then, the electroplating head drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating and pickling chamber as needed, and controls the dual-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. After pickling is completed, clean the chamber again. Subsequently, the electroplating head drives the wafer out of the Cu integrated electroplating and pickling chamber; S30, Nickel plating and pickling: The electroplating head holds the wafer and enters the Ni integrated electroplating and pickling chamber, then descends to the electroplating area to start wafer electroplating. After the Ni electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. After spin-drying, the sector nozzles in the cleaning area are opened to clean the integrated electroplating and pickling chamber, and then it is dried with nitrogen. Then, the electroplating head drives the wafer to rise to the pickling area, or directly controls the electroplating head to hold the wafer to the pickling position without cleaning the integrated electroplating and pickling chamber as needed, and controls the double-port nozzles to alternately spray dilute sulfuric acid and ultrapure water for the pickling step on the wafer surface. After pickling is completed, the chamber is cleaned again. Subsequently, the electroplating head drives the wafer out of the Ni integrated electroplating and pickling chamber; S40, Gold plating and spin-drying: The electroplating head moves the wafer into the gold plating chamber to deposit metal Au on the wafer surface. After the gold electroplating is completed, the electroplating head drives the wafer to rise and spin-dry. Then, the electroplating head drives the wafer to rise and leave the gold plating chamber. Finally, the electroplating head drives the wafer out of the hermetic treatment chamber; S50, Cleaning: The electroplating head moves the wafer after gold plating into the cleaning chamber for cleaning the wafer surface.

14. The electroplating process for improving the bonding strength between composite coatings according to claims 10 to 13, characterized in that, in the pickling step, the concentration of the dilute sulfuric acid is 5%, and the dilute sulfuric acid and ultrapure water are alternately sprayed 1 - 6 times. Each time of alternate spraying, the pickling time is 5 - 20 seconds, and the ultrapure water washing time is 10 - 40 seconds.

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