Electroplating bath for selective controllable semiconductor devices, electroplating apparatus and electroplating method

Abstract

The application discloses a kind of selective controllable semiconductor device electroplating tank, electroplating device and electroplating method, the electroplating device includes: electroplating tank, hanger and control system;The current stabilizing plate of electroplating tank;Variable frequency pump, stop valve, up and down plating area automatic control flow valve and up and down plating area automatic three-way switch valve.Control system is regulated by variable frequency pump total flow of electroplating solution;Automatic three-way switch valve automatically switches the flow direction of electroplating solution;Automatic control flow valve selects and controls the electroplating solution sub-flow of electroplating solution flow direction different plating area;Realize the precision semiconductor device electroplating equipment of different regions with different electroplating film thickness is handled simultaneously.The selective controllable electroplating method of the application is excellent, is favorable to realize the precision electroplating processing of high-end semiconductor device product, improves production efficiency, reduces production cost, meets the growing demand of semiconductor electronic industry to high-end precision electronic material for semiconductor device selective controllable electroplating effect.

Description

Technical Field

[0001] This invention relates to the field of semiconductor coating technology, specifically to a selectively controllable semiconductor device electroplating tank, electroplating apparatus, and electroplating method. Background Technology

[0002] Gold plating, characterized by its dense surface, high hardness, corrosion resistance, and excellent electrical conductivity, is widely used in semiconductor devices and electronic products in fields such as new energy vehicles, aerospace, and communications. It is particularly favored for high-precision, high-power electronic products. Therefore, in recent years, the development trend of high-end electroplating for gold plating in the electronics manufacturing industry has been unstoppable.

[0003] Currently, high-end electronic products have increasingly higher requirements for gold plating processes. The high-end design of electronic products in fields such as aerospace electronic products, new energy vehicle electronic products, and communications not only requires high precision in local gold plating areas, but also high production capacity and low budget. Therefore, high-precision local electroplating molds, electroplating equipment, and electroplating methods are needed to meet the needs of semiconductor device electronic products that are constantly developing towards high-end electroplating technology.

[0004] The plating process for single semiconductor electronic devices typically involves electroplating the entire part. However, with the increasing demand for high-end designs in fields such as new energy vehicle electronics, aerospace electronics, and communications, the requirements for localized electroplating are becoming more and more stringent. While using specialized electroplating masking tape to protect the non-plated areas of the part is a common method, it is only suitable for flat parts and cannot meet the requirements for localized electroplating on parts with complex shapes. In particular, when semiconductor devices have two or more different plating areas with varying film thicknesses, existing electroplating technologies cannot complete the electroplating process in one go.

[0005] There are currently no literature reports on solutions to the aforementioned technical problems. The existence of these scientific problems and technical difficulties in the field of semiconductor device and electronic product plating technology hinders the ever-growing demand for high-end precision electronic materials from the aerospace, new energy vehicle, and communication electronics industries, and is a research topic that urgently needs innovative breakthroughs. Summary of the Invention

[0006] The technical problem to be solved by this invention is that existing electroplating technologies cannot complete the electroplating process in one go for parts with two or more electroplating areas of different film thicknesses.

[0007] This invention provides a selectively controllable semiconductor device electroplating tank, comprising: an electroplating tank body, wherein the electroplating tank body has a space for placing electroplating fixtures, the electroplating tank body has multiple plating zone channels, and the outlet of each plating zone channel corresponds to the electroplating area of ​​the workpiece on the electroplating fixture; a pump, the pump being connected to the electroplating tank body and the electroplating channels, for delivering the electroplating solution from the electroplating tank body to the desired electroplating channel; and multiple flow control valves, each of the flow control valves controlling the flow rate of the electroplating solution in its corresponding plating zone channel, the flow control valves being connected to the pump and the corresponding plating zone channel.

[0008] Furthermore, the electroplating channels are grouped into pairs, corresponding to the front and back sides of the workpiece respectively, and the two electroplating channels in the same group are located at the same height in the electroplating tank.

[0009] Furthermore, the electroplating tank is provided with multiple plating zone channels from top to bottom.

[0010] Furthermore, a flow stabilizer is provided at the liquid outlet of each plating zone channel, and liquid outlet holes are evenly distributed on the flow stabilizer.

[0011] Furthermore, at least one partition is provided within the plating zone channel to divide each plating zone channel into at least two independent areas.

[0012] Secondly, the present invention also provides a selectively controllable semiconductor device electroplating apparatus, which employs the above-mentioned electroplating tank; it also includes an electroplating rack, wherein the electroplating rack includes an anode plate, a cathode conductive element, and a shielding component, wherein the cathode conductive element is used to electrically connect the plated part, and the shielding component is used to shield the non-electroplated area of ​​the plated part.

[0013] Furthermore, it also includes an anode conductive rod that connects to an anode plate; there are at least two anode plates, with an anode plate installed at the liquid outlet of each plating zone channel, and the anode plate is provided with liquid passage holes.

[0014] Furthermore, the electroplating fixture also includes a housing, inside which a mask is provided. The mask is made of a flexible and deformable material and is used to cover the non-electroplated areas of the workpiece to be plated. The housing and the mask are provided with hollow areas at corresponding positions. The shape of the hollow areas corresponds to the area of ​​the workpiece to be electroplated. The hollow areas correspond to the plating area channels.

[0015] Furthermore, the combined thickness of the mask and the plated part is greater than the thickness of the housing's accommodating space.

[0016] Furthermore, the difference between the thickness of the mask and the workpiece being plated and the thickness of the housing's accommodating space is 0.45–1.35 mm.

[0017] Furthermore, the thickness of the mask ranges from 1.4 to 3.3 mm.

[0018] Furthermore, the present invention also provides an electroplating method using a selectively controllable electroplating apparatus for semiconductor devices, comprising the following steps:

[0019] Step S1: Perform alkaline degreasing and acid activation treatment on the plated parts;

[0020] Step S2: Perform a base nickel plating treatment on the plated parts;

[0021] Step S3: Select the appropriate hanger for the different openwork plating areas based on the plating area and form of the part.

[0022] Step S4: Determine the electroplating time based on the size of the part to be plated, the required plating thickness, and the different surface areas to be plated; and determine the flow direction and flow rate of the electroplating solution based on the location of the plating area.

[0023] Step S5: Control the flow rate and direction of the corresponding plating zone channel according to the electroplating film thickness of different parts of the workpiece in the hanger.

[0024] Furthermore, the distance between the anode plate and the workpiece can be adjusted, with an adjustment range of 0.5~10mm.

[0025] Furthermore, the area of ​​the anode plate is 1.1 times the area of ​​the corresponding electroplating area. 1.5 times.

[0026] Furthermore, when the plated part is a single-sided electroplated product and is placed in the hanger, the flow control valve of the plating area channel corresponding to the plated surface of the part is opened, and the other flow control valves are closed.

[0027] Furthermore, when both sides of the plated part need to be electroplated, and the plated part is a stamped part, the flow rate of the corresponding plating zone channel on the front and back sides is differentiated.

[0028] Furthermore, when both sides of the workpiece need to be electroplated and the coating thickness is the same, a partition is also provided in each plating zone channel to divide each plating zone channel into two independent channels. When one of the independent channels is open, the other independent channel on the same side of the workpiece is closed, and the independent channel that is closer to the other independent channel on the other side of the workpiece is also closed, while the independent channel that is farther apart is opened.

[0029] Furthermore, the liquid passage holes of the anode plate are inclined so that the electroplating solution is poured into the surface of the workpiece at an upward angle.

[0030] Furthermore, the two independent channels within each plating zone are switched at a certain cycle.

[0031] The beneficial effects of this invention are as follows: A control system is employed to regulate the total flow rate of the electroplating solution via a variable frequency pump in the electroplating equipment; an automatic three-way switching valve automatically switches the flow direction of the electroplating solution; and an automatic flow control valve selects and controls the flow rate of the electroplating solution to different plating zones. This enables the simultaneous processing of precision semiconductor device electroplating products with varying film thicknesses in different areas. This invention's selective and controllable electroplating method provides excellent selective and controllable electroplating results for semiconductor devices, facilitating precision electroplating of high-end semiconductor devices, improving production efficiency, reducing production costs, and meeting the growing demand for high-precision electronic materials in the semiconductor electronics industry. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the electroplating tank provided in an embodiment of the present invention;

[0033] Figure 2 This is a schematic diagram of the plating zone channel provided in an embodiment of the present invention;

[0034] Figure 3 This is a schematic diagram of the hanging fixture structure provided in an embodiment of the present invention;

[0035] Figure 4 This is a plan view of the hanging fixture provided in an embodiment of the present invention;

[0036] Figure 5 This is a schematic diagram of the electroplating apparatus provided in an embodiment of the present invention;

[0037] Figure 6 This is a schematic diagram of the plated part structure provided in an embodiment of the present invention;

[0038] Figure 7 This is a schematic diagram of the anode plate structure in the upper plating area provided in an embodiment of the present invention;

[0039] Figure 8 This is a schematic diagram of the anode structure of the lower plating zone provided in an embodiment of the present invention;

[0040] Figure 9 This is a schematic diagram of the upper plating area flow stabilizing plate structure provided in an embodiment of the present invention;

[0041] Figure 10 This is a schematic diagram of the flow stabilizing plate structure in the lower plating area provided in an embodiment of the present invention;

[0042] Figure 11 This is a cross-sectional view of the anode plate provided in an embodiment of the present invention;

[0043] The diagram shows: 200, plated part; 300, electroplating tank; 30a, upper flow stabilizer plate; 30b, lower flow stabilizer plate; 31a, first plating zone channel; 31b, second plating zone channel; 32a, third plating zone channel; 32b, fourth plating zone channel; 50, variable frequency pump; 60a, first automatic control check valve; 60b, second flow control valve; 71a, first flow control valve; 71b, second flow control valve; 81a, third flow control valve; 81b, second flow control valve; 31a1, first independent channel; 31a2, second independent channel; 31b1, third independent channel; 31b2, fourth independent channel; 32aⅠ, fifth independent channel; 32aⅡ, sixth independent channel; 32bⅠ, seventh independent channel; 32bⅡ, eighth independent channel; 72a, First three-way switching valve; 72b, Second three-way switching valve; 82a, Third three-way switching valve; 82b, Fourth three-way switching valve; 220, Upper plating area; 230, Lower plating area; 222, Second film thickness test point; 231, First film thickness test point; 150, Upper anode plate; 160, Lower anode plate; 170, Anode conductive rod; 110, Cathode conductive component. Detailed Implementation

[0044] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0046] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0047] The electroplating tank of the present invention, such as Figure 1 As shown, the system includes an electroplating tank 300, with space within the tank for placing electroplating fixtures 100. The tank 300 has an upper electroplating zone and a lower electroplating zone. The upper electroplating zone has a first plating channel 31a and a second plating channel 31b, while the lower electroplating zone has a third plating channel 32a and a fourth plating channel 32b. Each plating channel's outlet corresponds to the plating area of ​​the workpiece on the fixture. An outlet is located at the bottom of the tank 300, and a variable frequency pump 50 is installed at the outlet. The variable frequency pump 50 connects to the tank 300 and the plating channels, transporting the electroplating solution from the tank 300 to both sides of the workpiece 200 via two delivery pipes. A first automatic control check valve 60a and a second automatic control check valve 60b are also installed on the two delivery pipes. Each plating zone channel is equipped with a corresponding flow control valve. The first plating zone channel 31a and the second plating zone channel 31b are equipped with a first flow control valve 71a and a second flow control valve 71b, respectively. The third plating zone channel 32a and the fourth plating zone channel 32b are equipped with a third flow control valve 81a and a fourth flow control valve 81b, respectively. Each flow control valve controls the flow rate of the electroplating solution in its corresponding plating zone channel, and the flow control valve is connected to a variable frequency pump 50.

[0048] The electroplating channels are grouped in pairs, corresponding to the front and back sides of the workpiece 200, respectively. The two electroplating channels in the same group are located at the same height within the electroplating tank 300. If the first plating zone channel 31a and the second plating zone channel 31b are grouped together, then the third plating zone channel 32a and the fourth plating zone channel 32b are grouped together.

[0049] An upper flow stabilizer 30a is installed at the liquid outlet of the first plating zone channel 31a and the second plating zone channel 31b in the upper plating zone. The upper flow stabilizer 30a is as follows: Figure 9 As shown, a lower flow stabilizer 30b is installed at the liquid outlet of the third plating channel 32a and the fourth plating channel 32b in the lower plating zone.

[0050] like Figure 2As shown, at least one baffle is installed within each plating zone channel to divide each plating zone channel into at least two independent areas. The first plating zone channel 31a is divided into a first independent channel 31a1 and a second independent channel 31a2; the second plating zone channel 31b is divided into a third independent channel 31b1 and a fourth independent channel 31b2; the third plating zone channel 32a is divided into a fifth independent channel 32aⅠ and a sixth independent channel 32aⅡ; and the fourth plating zone channel 32b is divided into a seventh independent channel 32bⅠ and an eighth independent channel 32bⅡ. The baffles are perpendicular to the corresponding flow stabilizers. Each plating zone channel is also equipped with a three-way switching valve. The first plating zone channel 31a and the second plating zone channel 31b are equipped with a first three-way switching valve 72a and a second three-way switching valve 72b, respectively; and the third plating zone channel 32a and the fourth plating zone channel 32b are equipped with a third three-way switching valve 82a and a fourth three-way switching valve 82b, respectively. The three-way switching valves are used for switching between two independent channels within the same plating zone channel.

[0051] 200 pieces to be plated Figure 6 As shown, the plated part 200 has dimensions of 120×55mm and a thickness of 0.25mm. The plated part 200 includes an upper plating area 220 and a lower plating area 230. It is double-sided electroplated. Each terminal in the upper partial plating area is 29.7mm long and 6.0mm wide; each terminal in the lower plating area is 15.7mm long and 2.4mm wide. The area within the dashed line represents the product inspection range for judging the electroplating appearance, plating adhesion, and other performance characteristics. The upper plating area 220 and the lower plating area 230 are respectively equipped with a second film thickness test point 222 and a first film thickness test point 231. The area of ​​the upper plating area 220 on both sides of the four terminals in each of the upper and lower plating areas is:

[0052] 2×4×29.7×(6.0 + 0.25) = 1485mm 2 = 0.1485dm 2 .

[0053] The area of ​​the lower plating zone 230 on both sides is 2×4×15.7×(2.4 + 0.25) = 332.84mm². 2 =0.033284dm 2

[0054] The total area of ​​the plating zone is = 0.1485 + 0.033284 = 0.18178 dm² 2 .

[0055] In this embodiment, the structure of the hanger 100 is as follows: Figure 3 and Figure 4As shown, the structure of the plating rack 100 needs to match the structure of the electroplating tank. The electroplating rack 100 includes an upper anode plate 150, a lower anode plate 160, an anode conductive rod 170, a cathode conductive element 110, and a shielding assembly. The cathode conductive element 110 is used to electrically connect to the workpiece 200, and the shielding assembly is used to shield the non-plating areas of the workpiece 200. The anode conductive rod 170 is used to connect to the anode plate. An anode plate 150 is installed at the outlet of each plating zone channel, and the anode plate has liquid passage holes, such as... Figure 7 , Figure 8 and Figure 10 As shown. The axis of the liquid passage is inclined upwards from the direction away from the plated part 200 to the direction near the plated part 200, forming an angle of 35° to 80° with the vertical plane, such as... Figure 11 As shown. The diameter range of the liquid passage hole is 0.2 mm. 5.0mm.

[0056] like Figure 4 As shown, the electroplating fixture 100 also includes a housing, within which a mask is disposed. The mask is made of a flexible, deformable material, such as silicone rubber. The thickness of the mask is preferably in the range of 1.0 mm. 2.5mm. It is used to mask the non-electroplated areas of the part to be plated 200. Both the housing and the mask have corresponding perforated areas, the shape of which corresponds to the area of ​​the part to be plated 200, and the perforated areas correspond to the plating channels. The combined thickness of the mask and the part to be plated 200 is greater than the thickness of the housing's accommodating space. The difference between the combined thickness of the mask and the part to be plated 200 and the thickness of the housing's accommodating space is preferably 0.45–1.35mm. After all components of the hanger 100 are assembled, they are fixed with locking screws to form a sealed hanger 100; the locking screws can be made of titanium, SUS316, or non-metallic materials such as PP or PEEK.

[0057] The electroplating rack 100 and the electroplating tank are combined to form an electroplating apparatus, such as Figure 5 As shown. Configure the control system touchscreen.

[0058] The electroplating method of the present invention will be specifically described below using examples.

[0059] Example 1

[0060] Part 200 undergoes pretreatment including degreasing, pickling, and acid activation, followed by overall nickel plating at 1300. After 1500nm, it is set in the hanger 100. The upper plating area 220 requires a gold film thickness of ≥300nm, and the lower plating area 230 requires a gold film thickness of ≥100nm. The electroplating conditions are calculated based on the total area of ​​the plating area. The results are: current 2.5A (amperes), electroplating time 26 seconds, and solution temperature 50℃.

[0061] The ratio of the area of ​​the upper plating zone 220 to the area of ​​the lower plating zone 230 is 0.1485 : 0.033284 = 4.44 : 1, meaning the area of ​​the upper plating zone 220 is 4.44 times that of the lower plating zone 230, and the film thickness of the upper plating zone 220 is 5 times that of the lower plating zone 230. Therefore, the flow rate of the upper plating zone 220a and b surfaces needs to be controlled by adjusting the first flow control valve 71a and the second flow control valve 71b; the optimal upper limit value of 125 L / min is selected. The area and film thickness of the lower plating zone 230 are 4.4 to 5 times lower than those of the upper plating zone. Therefore, the third flow control valve 81a and the fourth flow control valve 81b control the low flow rate, with an optimal lower limit value of 7.5 L / min selected. The ratio of the flow rate of the upper plating zone 220 to the flow rate of the lower plating zone 230 is 125 : 7.5 = 16.6 times.

[0062] Increasing the number of contacts between the electroplating solution and the surface of the workpiece 200 per unit time can improve the efficiency and quality of the deposited metal coating. As is well known, through the accumulation of a large amount of practical experience in electroplating production, increasing the number of effective contacts between the surface of the workpiece 200 and the electroplating solution is beneficial to increasing the coating deposition rate. The greater the increase in the flow rate of the electroplating solution, the more beneficial it is to increasing the coating deposition rate; conversely, the greater the decrease in the flow rate of the electroplating solution, the more beneficial it is to decreasing the coating deposition rate.

[0063] The distance between the anode and the workpiece 200 is also one of the factors affecting the deposition rate of the coating. Within a certain range, the closer the distance between the anode and the workpiece 200, the more conducive it is to increasing the deposition rate of the coating; conversely, the farther the distance between the anode and the workpiece 200, the more conducive it is to reducing the deposition rate of the coating.

[0064] Since the area and film thickness requirements of the upper plating zone 220 are much higher than those of the lower plating zone 230, increasing the electroplating solution flow rate of the upper plating zone 220 and reducing the distance between the anode and the workpiece 200 when setting the electroplating conditions will help increase the thickness of the precipitated coating. Conversely, reducing the electroplating solution flow rate of the lower plating zone 230 and increasing the distance between the anode and the workpiece 200 will reduce the thickness of the precipitated coating.

[0065] The electroplating efficiency is adjusted by varying the density of the through-holes on the anode plate. A smaller diameter and denser distribution of the through-holes in the upper plating zone 220 results in a larger platinum plating surface area per unit area and a faster plating rate. Conversely, a smaller platinum plating surface area per unit area results in a slower plating rate. The upper plating zone 220 has 23 × 15 × 2 = 690 holes on the anode plate (150), and the lower plating zone 230 has 6 × 5 × 2 = 60 holes on the anode plate (160). The ratio of the number of holes in the upper plating zone 220 to the number of holes in the lower plating zone 230 is 690 ÷ 60 = 11.5 times.

[0066] Furthermore, after the current conditions are set, depending on the different electroplating areas, the more the surface of the plating area contacts and exchanges with the electroplating solution, the faster the metal coating is deposited and the thicker the film is; conversely, the less the surface contacts and exchanges with the electroplating solution, the slower the metal coating is deposited and the thinner the film is.

[0067] The parameter settings for Example 1 are shown in Table 1.

[0068] The electroplating requirements for Example 2 are the same as those for Example 1. To confirm the changing trend of the precipitated metal coating with increasing electroplating solution flow rate, the flow rate of the upper plating zone 220 was gradually increased from 125 L / min to 250 L / min, and the flow rate of the lower plating zone 230 was decreased from 7.5 L / min to 4 L / min. The distance between the anode and the workpiece 200 was reduced by 2 mm in the upper plating zone 220 from 6 mm, while remaining unchanged at 9 mm in the lower zone. Other conditions were the same as in Example 1. The conditions for all examples are shown in Table 1.

[0069] Example 1 Example 5: The semiconductor device product was processed using the electroplating equipment of the control system of the present invention according to the conditions in Table 1. The resulting semiconductor device product was subjected to appearance inspection, coating thickness test and nitric acid vapor corrosion resistance test.

[0070] Visual inspection: Observe using a 40x optical microscope and an electron microscope at 5000x magnification, and judge according to the following standards:

[0071] Excellent: The gold plating layer should be uniform, smooth, without any missed plating or seepage, and the electroplating area should remain unchanged. The total defect area should be 0.0. It is rated as excellent.

[0072] Good: The gold plating layer is uniform, smooth, without any missed plating or seepage, and the plating area remains unchanged. The total absolute value of the defects is less than 2% of the overall test area.

[0073] Medium: The uniformity, smoothness, absence of missed plating, absence of seepage plating, and unchanged electroplating area of ​​the gold plating layer are all acceptable. The defect area is greater than 2% of the total test area, and the absolute value of the total defect area is less than 5% of the total test area. The evaluation is medium.

[0074] Unacceptable: If the uniformity, smoothness, absence of plating defects, absence of plating seepage, or unchanged plating area of ​​the gold plating layer are not met, and the total absolute area of ​​defects exceeds 5% of the overall test area, the evaluation is unacceptable.

[0075] The results are shown in Table 2.

[0076] Tin-gold layer thickness testing: Tested using a Fischer FISCHERSCOPE X-RAY XDV-SDD measuring instrument. Figure 2 The gold plating film thickness at the center of 24 white circles in the upper, middle and lower regions of the first and second areas of the semiconductor device electronic product plated part 200.

[0077] Table 1. Implementation Conditions

[0078]

[0079] Table 2 Example 1 Example 5: Visual Inspection

[0080]

[0081] As can be seen from Table 2, Example 1 Based on the results of the 5000x magnification electron microscope examination of surface a and surface b of Example 5, the results of the non-penetration plating and the electroplated area inspection were rated as excellent and good, respectively; the overall evaluation of surface a and surface b was excellent.

[0082] Table 3. Example 1: Gold plating film thickness (nm)

[0083]

[0084] Table 4 Example 1 Example 5: Gold plating film thickness (nm)

[0085]

[0086]

[0087] As shown in Table 3, the double-sided electroplating of Example 1, which requires a gold film thickness of ≥300nm for the upper region and ≥100nm for the lower region, yielded a result where the upper region film thickness was more than 100nm greater than the lower region film thickness by using the control system electroplating equipment of the present invention and setting various process conditions. Although the requirements of ≥300nm for the upper region and ≥100nm for the lower region have not yet been met, the following experiments will further explore the optimal conditions by increasing the flow rate of the electroplating solution and decreasing the distance between the upper anode and the workpiece.

[0088] As shown in Table 4, in Examples 2 and 5, while gradually increasing the flow rate of the electroplating solution in the upper plating zone and gradually decreasing the flow rate of the electroplating solution in the lower plating zone, the distance between the anode in the upper plating zone and the workpiece 200 was gradually reduced. Through conditional exploration, the average gold film thickness on side a of the upper plating zone increased from 234 nm to 316 nm, and on side b from 232 nm to 314 nm; the average gold film thickness on side a of the lower plating zone increased from 94 nm to 117 nm, and on side b from 93 nm to 118 nm; finally, the minimum range of the gold film thickness on side a of the upper plating zone in Example 5 was 305 nm. Max 321nm, B-side gold film thickness range Min 303nm Max 322nm; Gold film thickness range of the lower plating area a-side: Min 103nm Max 127nm, B-side gold film thickness range Min 105nm Max129nm; that is, the upper plating area of ​​the gold plating layer of the semiconductor device prepared under the conditions of Example 5 meets the requirement of ≥300nm, and the lower plating area also meets the requirement of ≥100nm.

[0089] The nitric acid vapor test was conducted according to the national standard GB / T 19351-2003 / ISO 14647:2000. 3M electroplating protective tape was used to bond and protect the non-plated areas. The upper area of ​​the plated sample (25mm × 6.0mm) and the lower area (13mm × 2.4mm) were used for the test, which lasted for 1 hour.

[0090] The corrosion resistance of the gold plating was judged according to the following standards: 0.0% corrosion area was rated as excellent; 0.0% < corrosion area ≤ 1.0% was rated as good; 1.0% < corrosion area ≤ 2.0% was rated as average; and 2.0% < corrosion area was rated as unqualified. The experimental results are listed in Table 5.

[0091] Table 5 Example 1 Example 5: Corrosion rate test results (%) of nitric acid gas experiment

[0092]

[0093] As shown in Table 5, Example 1 The nitric acid vapor test results of Example 5 showed that the corrosion areas of the top-plated areas a and b were 0.08%, 0.07%, 0.02%, 0.02%, and 0.01%, respectively. According to the evaluation standard of 0.0% < corrosion area ≤ 1.0%, this is rated as good. However, considering that the corrosion area is less than 0.1%, it is less than one-tenth of the standard for good. Therefore, Example 1 can be judged... All results in Example 5 were excellent.

[0094] Further, Example 1 In Example 5, the corrosion areas of the lower plating areas a and b were 0.09%, 0.08%, 0.04%, 0.03%, and 0.02%, respectively. According to the evaluation standard of 0.0% < corrosion area ≤ 1.0%, this is rated as good. However, further analysis shows that the actual corrosion area is less than 0.1%, which is less than one-tenth of the standard for good evaluation. Therefore, Example 1 can be judged... All results in Example 5 were excellent.

[0095] In summary, this invention, based on a selectively controllable semiconductor device electroplating equipment, employs a control system that regulates the total flow rate of the electroplating solution via a variable frequency pump. An automatic three-way switching valve automatically switches the flow direction of the electroplating solution, and an automatic flow control valve selects and controls the flow rate of the electroplating solution to different plating zones. This enables the simultaneous processing of precision semiconductor device electroplating products with varying film thicknesses in different areas. This selectively controllable electroplating method offers excellent selective electroplating results for semiconductor devices, facilitating precision electroplating of high-end semiconductor devices, improving production efficiency, reducing production costs, and meeting the growing demand for high-precision electronic materials in the semiconductor electronics industry.

Claims

1. A selectively controllable semiconductor device electroplating bath, characterized in that: include: An electroplating tank (300) is provided with a space inside for placing an electroplating fixture (100). The electroplating tank (300) is provided with multiple plating zone channels, and the outlet of each plating zone channel corresponds to the plating area of ​​the plating part (200) on the electroplating fixture (100). A pump, which is connected to the electroplating tank (300) and the electroplating channel, delivers the electroplating solution in the electroplating tank (300) to the required electroplating channel; Multiple flow control valves, each of which controls the flow rate of the electroplating solution in the corresponding plating zone channel, and the flow control valves are connected to the pump and the corresponding plating zone channel; The electroplating channels are grouped into two, corresponding to the front and back sides of the plated part (200) respectively. The two electroplating channels in the same group are located at the same height in the electroplating tank (300). A flow stabilizer is provided at the liquid outlet of each plating zone channel, and liquid outlet holes are evenly distributed on the flow stabilizer. At least one partition is also provided in the plating zone channel to divide each plating zone channel into at least two independent areas.

2. The selectively controllable semiconductor device electroplating bath according to claim 1, characterized in that: The electroplating tank (300) is provided with multiple plating zone channels from top to bottom.

3. A selectively controllable semiconductor device electroplating apparatus, characterized in that: The electroplating tank as described in any one of claims 1-2 is used; It also includes an electroplating rack (100), which includes an anode plate, a cathode conductive element (110), and a shielding assembly. The cathode conductive element (110) is used to electrically connect the plated part (200), and the shielding assembly is used to shield the non-plated area of ​​the plated part (200).

4. The selectively controllable semiconductor device electroplating apparatus according to claim 3, characterized in that: It also includes an anode conductive rod (170) that connects to an anode plate; there are at least two anode plates, and an anode plate is provided at the liquid outlet of each plating zone channel, and the anode plate is provided with liquid passage holes.

5. The selectively controllable semiconductor device electroplating apparatus according to claim 4, characterized in that: The axis of the liquid passage is inclined upward from the direction away from the plated part (200) to the direction closer to the plated part (200), and forms an angle of 35° to 80° with the vertical plane.

6. The selectively controllable semiconductor device electroplating apparatus according to claim 5, characterized in that: The electroplating fixture (100) also includes a housing, and a mask is provided inside the housing. The mask is made of a flexible and deformable material and is used to cover the non-electroplated area of ​​the part to be plated (200). The housing and the mask are provided with hollow areas at corresponding positions. The shape of the hollow areas corresponds to the area of ​​the part to be plated (200). The hollowed-out area corresponds to the plating zone channel.

7. The selectively controllable semiconductor device electroplating apparatus according to claim 6, characterized in that: The combined thickness of the mask and the plated part (200) is greater than the thickness of the housing's accommodating space.

8. The selectively controllable semiconductor device electroplating apparatus according to claim 7, characterized in that: The difference between the thickness of the mask and the part to be plated (200) superimposed and the thickness of the housing space is 0.45 to 1.35 mm.

9. The selectively controllable semiconductor device electroplating apparatus according to claim 7, characterized in that: The thickness of the mask ranges from 1.4 to 3.3 mm.

10. An electroplating method using a selectively controllable electroplating apparatus for semiconductor devices, employing the electroplating apparatus as described in any one of claims 3 to 9, characterized in that: Includes the following steps: Step S1: Perform alkaline degreasing and acid activation treatment on the plated part (200); Step S2: Perform a base nickel plating treatment on the plated part (200); Step S3: Select the appropriate hanger (100) for different hollow plating areas according to the electroplating area and form of the plated part (200). Step S4: Determine the electroplating time based on the size of the part (200), the required plating thickness, and the different surface areas to be electroplated; and determine the flow direction and flow rate of the electroplating solution based on the different locations of the plating area. Step S5: Control the flow rate and direction of the corresponding plating zone channel according to the electroplating film thickness of different parts of the plated part (200) in the hanger (100).

11. The electroplating method of the semiconductor device selective controllable electroplating equipment according to claim 10, characterized in that: The distance between the anode plate and the workpiece (200) can be adjusted, with an adjustment range of 0.5~10mm.

12. The electroplating method of the semiconductor device selective controllable electroplating equipment according to claim 10 or 11, characterized in that: The area of ​​the anode plate is 1.1 times the area of ​​the corresponding electroplating area. 1.5 times.

13. The electroplating method of the semiconductor device selective controllable electroplating equipment according to claim 10 or 11, characterized in that: When the plated part (200) is a single-sided electroplated product, and the plated part (200) is placed in the hanger (100), the flow control valve of the plating area channel corresponding to the plated surface of the plated part (200) is opened, and the other flow control valves are closed. When both sides of the plated part (200) need to be electroplated, and the plated part (200) is a stamped part, the flow rate of the corresponding plating zone channel on the front and back sides is differentiated.

14. The electroplating method of the semiconductor device selective controllable electroplating equipment according to claim 10 or 11, characterized in that: When both sides of the plated part (200) need to be electroplated and the coating thickness is the same, a partition is also provided in each of the plating zone channels to divide each plating zone channel into two independent channels. When one of the independent channels is opened, the other independent channel on the same side of the plated part (200) is closed, and the independent channel that is closer to the other independent channel on the other side of the plated part (200) is also closed, while the independent channel that is farther apart is opened.

15. The electroplating method of the semiconductor device selective controllable electroplating equipment according to claim 10 or 11, characterized in that: The liquid passage holes of the anode plate are set at an angle so that the electroplating solution is poured into the surface of the workpiece (200) at an upward angle.

16. The electroplating method of the semiconductor device selective controllable electroplating equipment according to claim 14, characterized in that: The two independent channels within each plating zone are switched at a certain cycle.

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