Electroplating system and method

Abstract

In a general aspect, an electroplating system (100) includes a vessel (105), an electrolytic plating bath (110) in the vessel, a cathode terminal (120), a first anode terminal (130) and a second anode terminal (140), a first variable power source (135) and a second variable power source (145). The cathode terminal is configured to electrically connect with a workpiece (125) submerged in the electrolytic plating bath. The first anode terminal is in the electrolytic plating bath at the first side of the workpiece. The second anode terminal is in the electrolytic plating bath at a second side of the workpiece opposite the first side. A first variable power supply is coupled between the cathode terminal and the first anode terminal. A second variable power supply is coupled between the cathode terminal and the second anode terminal.

Description

[0001] Related Applications

[0002] This application claims priority to and the benefit of U.S. Application No. 18 / 341,958, filed on June 27, 2023, which is incorporated herein by reference in its entirety. Technical Field

[0003] The present description relates to electroplating, such as electroplating of semiconductor device components. Background Art

[0004] Electrochemical processes (such as electroplating) can be used to plate metal surfaces (e.g., exposed copper surfaces) of semiconductor device components (device components, components, etc.), such as exposed metal surfaces of lead frames, metal seed layers on substrates, direct bonding metal layers on substrates, etc. For example, such processes can be used to perform tin plating (or plating with other metals), wherein such plating can prevent corrosion (e.g., oxidation) of corresponding metal surfaces (such as copper), and improve the solderability of metal surfaces of semiconductor device components. However, existing electroplating methods may have certain disadvantages, such as uneven plating thickness, wherein the plating thickness of the metal surface on one side of the component is undesirably thicker than the plating thickness of the metal surface on the opposite side of the component. Since excess plating material can create undesirable conductive paths, such thicker plating can cause leakage and / or electrical short circuits (e.g., between signal pins or pads and / or power pins and / or terminals, etc.). Moreover, due to the consumption of excess plating material, such existing methods can increase overall operating and / or product costs. Summary of the invention

[0005] In a general aspect, an electroplating system includes a container, an electrolytic plating solution in the container, a cathode terminal, a first anode terminal and a second anode terminal, and a first variable power supply and a second variable power supply. The cathode terminal is configured to be electrically connected to a workpiece immersed in the electrolytic plating solution. The first anode terminal is in the electrolytic plating solution on a first side of the workpiece. The second anode terminal is in the electrolytic plating solution on a second side of the workpiece opposite the first side. The first variable power supply is coupled between the cathode terminal and the first anode terminal. The second variable power supply is coupled between the cathode terminal and the second anode terminal.

[0006] Specific implementations may include one or more of the following features, alone or in combination.For example, the first variable power supply may include a first variable voltage power supply, and the second variable power supply may include a second variable voltage power supply.

[0007] The first variable power supply may include a first variable current power supply, and the second variable power supply may include a second variable current power supply.

[0008] The first anode terminal and the second anode terminal may each include a solid plating material that is soluble in an electrolytic plating solution.

[0009] The electrolytic plating solution may include methanesulfonic acid (MSA) and a liquid plating material.

[0010] The electroplating system may include a third anode terminal in the electrolytic plating solution on the first side of the workpiece and a fourth anode terminal in the electrolytic plating solution on the second side of the workpiece. The electroplating system may include a third variable power supply coupled between the cathode terminal and the third anode terminal and a fourth variable power supply coupled between the cathode terminal and the fourth anode terminal.

[0011] The third variable power supply may include a first variable voltage power supply, and the fourth variable power supply may include a second variable voltage power supply.

[0012] The third variable power supply may include a first variable current power supply, and the fourth variable power supply may include a second variable current power supply.

[0013] The workpiece may be a strip of bulk molded semiconductor device assemblies.

[0014] In another general aspect, a method includes electrically coupling a workpiece to a common cathode terminal of an electroplating system and immersing the workpiece in an electrolytic plating solution. The method also includes supplying a first plating current from a first anode terminal immersed in the electrolytic plating solution for electroplating at least one platable surface of a first side of the workpiece. The method also includes supplying a second plating current from a second anode terminal immersed in the electrolytic plating solution for electroplating at least one platable surface of a second side of the workpiece. The second plating current is different from the first plating current, and the second side of the workpiece is opposite to the first side of the workpiece.

[0015] Implementations may include one or more of the following features, alone or in combination.For example, the workpiece may be a bulk molded semiconductor device assembly strip.

[0016] The first plating current may be based on an area of ​​at least one plateable surface of the first side of the workpiece. The second plating current may be based on an area of ​​at least one plateable surface of the second side of the workpiece.

[0017] The first plating current can be used to plate a first portion of at least one platable surface of a first side of the workpiece, and the second plating current can be used to plate a first portion of at least one platable surface of a second side of the workpiece. The method may include supplying a third plating current from a third anode terminal immersed in the electrolytic plating solution for electroplating a second portion of at least one platable surface of the first side of the workpiece. The method may also include supplying a fourth plating current from a fourth anode terminal immersed in the electrolytic plating solution for electroplating a second portion of at least one platable surface of the second side of the workpiece.

[0018] The third plating current may be different from the first plating current, and the fourth plating current may be different from the second plating current.

[0019] The third plating current may be equal to the first plating current, and the fourth plating current may be equal to the second plating current.

[0020] The third plating current may be equal to the first plating current, and the fourth plating current may be different from the second plating current.

[0021] In another general aspect, an electroplating system includes a container, an electrolytic plating solution including a liquid plating material in the container, a common cathode terminal, a first anode terminal, a second anode terminal, a third anode terminal, a fourth anode terminal, a first variable power supply, a second variable power supply, a third variable power supply, and a fourth variable power supply.

[0022] The common cathode terminal is configured to be electrically connected to a workpiece immersed in an electrolytic plating solution. The first anode terminal and the second anode terminal are in the electrolytic plating solution on a first side of the workpiece. The third anode terminal and the fourth anode terminal are in the electrolytic plating solution on a second side of the workpiece opposite the first side. The first variable power supply is coupled between the common cathode terminal and the first anode terminal. The second variable power supply is coupled between the common cathode terminal and the second anode terminal. The third variable power supply is coupled between the common cathode terminal and the third anode terminal. The fourth variable power supply is coupled between the common cathode terminal and the fourth anode terminal.

[0023] Specific implementations may include one or more of the following features, alone or in combination. For example, the first variable power supply may include a first variable voltage power supply. The second variable power supply may include a second variable voltage power supply. The third variable power supply may include a third variable voltage power supply. The fourth variable power supply may include a fourth variable voltage power supply.

[0024] The first variable power supply may include a first variable current power supply. The second variable power supply may include a second variable current power supply. The third variable power supply may include a third variable current power supply. The fourth variable power supply may include a fourth variable current power supply.

[0025] The workpiece may be a strip of bulk molded semiconductor device assemblies. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a diagram schematically illustrating an exemplary electroplating system.

[0027] Figure 2 is a diagram schematically illustrating another exemplary electroplating system.

[0028] Figure 3 is a diagram illustrating an exemplary block molded semiconductor device assembly strip viewed from a first side (eg, top side).

[0029] Figure 4 is shown viewed from the second side (eg, bottom side) Figure 3 Figure 2. A diagram of a bulk molded semiconductor device assembly strip.

[0030] Figure 5 It is shown Figure 3 and Figure 4 A diagram of a plated area (eg, on the bottom side) of a semiconductor device component of a block molded semiconductor device component strip.

[0031] Figure 6 is a flow chart illustrating an exemplary method for electroplating. DETAILED DESCRIPTION

[0032] The present disclosure relates to electroplating systems (plating systems, systems, etc.) and related methods that address at least some of the disadvantages of the above-mentioned previous methods. For example, the plating systems and methods described herein can reduce the non-uniformity of the plating thickness on the surface (e.g., the plateable surface) of the opposite side of a semiconductor device component (such as a bulk molded semiconductor device component or a package strip). Such bulk molded strips can have different plateable surface areas on opposite sides, for example, a first plateable surface area on the top side of the strip and a different second plateable surface area on the bottom side of the strip. For the purposes of the present disclosure, the molding compound surface is not a plateable surface.

[0033] In the disclosed method, a separate variable power supply (e.g., variable voltage and / or current) can be used to supply corresponding plating currents (e.g., based on the corresponding area of ​​the corresponding plating surface) to the plating surface of each side of the semiconductor component, rather than providing a single fixed plating current as in the prior art. For example, if the corresponding plating surfaces have different areas and / or are asymmetric, the prior art plating method can produce an undesirable thicker coating on the plating surface of one side of the component, where the area of ​​the plating surface is a relatively small area, for example, compared to the area of ​​the plating surface on the opposite side.

[0034] In contrast, using the exemplary implementations described herein, different plating currents may be provided (e.g., on each side of a component) such that equal or approximately equal plating current densities (e.g., in amperes (A) per square decimeter (dm2)) are used for the respective plated surfaces on each side of the component (e.g., the top and bottom sides). 2 ) in units), where the corresponding plateable surfaces are asymmetric and / or have different surface areas.

[0035] In addition, due to the improved uniformity of the coating thickness, the exemplary method described herein can reduce manufacturing and / or product costs by reducing the amount of the plating material used. In addition, by improving the plating uniformity, leakage and / or electrical short circuits can be prevented, particularly in components with close spacing (e.g., small distances between signal pins, signal pads and / or other plating surfaces), because it is possible to prevent the application of undesirable excess plating materials that may cause such leakage and / or short circuits. Therefore, compared with existing methods, the disclosed specific implementation can promote spacing reduction. Such spacing reduction can allow the corresponding size of the semiconductor device assembly to be reduced, which can therefore achieve additional operation and / or product cost savings, such as reduced material costs.

[0036] Figure 1 1 is a diagram schematically illustrating an exemplary electroplating system 100. The electroplating system 100 includes a container 105 in which an electrolytic plating solution 110 is disposed. In some implementations, the electrolytic plating solution 110 may include methanesulfonic acid (MSA) or an equivalent electrolytic solution (such as nickel sulfamate or copper sulfate) and a liquid metal solution, wherein the liquid metal solution includes a metal (e.g., a liquid plating metal, such as liquid tin) for a platable surface (such as an exposed metal surface) of a workpiece 125, which is immersed (e.g., disposed) in the electrolytic plating solution 110. In some implementations, the electrolytic plating solution 110 may include one or more additives to promote effective electroplating. Other surfaces of the workpiece 125 disposed in the electrolytic plating solution 110 may be non-platable, such as a molding compound surface.

[0037] like Figure 1 As shown, the electroplating system 100 includes a distributor 115 disposed within the electrolytic plating solution 110 in the container 105. In some implementations, the position of the distributor 115 within the container 105 can be adjusted, for example, Figure 1 In the view of FIG. 1 , the vertical adjustment is based on the size of the workpiece 125 to be plated. Figure 1As indicated by arrows 115a in FIG. 1 , the distributor 115 can generate a fluid flow within the electrolytic plating solution 110. The fluid flow can agitate the electrolytic plating solution 110 (e.g., to maintain uniformity of the electrolytic plating solution 110 and / or to promote plating efficiency). In some implementations, the distributor 115 can generate a laminar flow of the electrolytic plating solution 110 on the workpiece 125.

[0038] Figure 1 The electroplating system 100 includes a cathode terminal 120. The cathode terminal 120 includes a clip 120a for physically and electrically coupling the cathode terminal 120 to a workpiece 125, for example, electrically coupling the cathode terminal 120 to a surface of the workpiece 125 to be plated, such as a lead frame strip including a plurality of semiconductor device components, such as a bulk molded device component strip. Figure 1 A single clip (clip 120a) is shown in FIG. 1 , but in some implementations, the cathode terminal 120 may include multiple clips for electrically coupling to the workpiece 125 and for positioning the workpiece 125 within the electrolytic plating solution 110.

[0039] exist Figure 1 In the example of FIG. 1 , the electroplating system 100 further includes an anode terminal 130 and an anode terminal 140, wherein the anode terminal 130 is disposed on a first side of the workpiece 125 and the cathode terminal 120, and the anode terminal 140 is disposed on a second side of the workpiece 125 and the cathode terminal 120 opposite to the first side. That is, in this view, the anode terminal 130 is disposed in the electrolytic plating solution 110 on the left side of the cathode terminal 120 and the workpiece 125, and the anode terminal 140 is disposed in the electrolytic plating solution 110 on the right side of the cathode terminal 120 and the workpiece 125.

[0040] like Figure 1 As shown, the variable power supply 135 is coupled between the cathode terminal 120 and the anode terminal 130, and the variable power supply 145 is coupled between the cathode terminal 120 and the anode terminal 140. In this example, the variable power supply 135 provides a plating current from the anode terminal 130 to the cathode terminal 120 for plating the platable surface on the left side of the workpiece 125 (which may also be referred to as the bottom side of the workpiece 125 in some specific implementations). The variable power supply 145 provides a plating current from the anode terminal 140 to the cathode terminal 120 for plating the platable surface on the right side of the workpiece 125 (which may also be referred to as the top side of the workpiece 125 in some specific implementations). That is, in the electroplating system 100, the cathode terminal 120 is a common cathode terminal of the anode terminal 130, the variable power supply 135, the anode terminal 140, and the variable power supply 145.

[0041] In the electroplating system 100, the anode terminal 130 includes a base portion 130a and a soluble portion 130b disposed on the base portion 130a, and the anode terminal 140 includes a base portion 140a and a soluble portion 140b disposed on the base portion 140a. In this example, the base portion 130a and the base portion 140a can be formed of a material having a low electrical resistance that is not easily consumed in the electrolytic plating solution 110, such as during electroplating of the workpiece 125. For example, in some implementations, the base portion 130a and the base portion 140a can each include a titanium anode basket or an equivalent anode material.

[0042] The soluble portion 130b and the soluble portion 140b may include a solid electroplating metal that is soluble in the electrolytic plating solution 110, such as tin or other electroplating metals. Therefore, in this example, the soluble portion 130b and the soluble portion 140b are at least partially consumed during the electroplating of the workpiece 125. That is, the soluble portion 130b and the soluble portion 140b provide a consumable plating metal that is combined with the plating metal that has been dissolved in the electrolytic plating solution 110 for plating the platable surface of the workpiece 125 (and / or other workpieces). Therefore, at least the soluble portion 130b of the anode terminal 130 and the soluble portion 140b of the anode terminal 140 will be regularly replenished, such as in the specific implementation of the electroplating system 100 used in the semiconductor device assembly manufacturing process. In some specific implementations, the base portion 130a and the base portion 140a may also be replaced regularly, but not as frequently as the soluble portion 130b and the soluble portion 140b.

[0043] In some specific implementations, the variable power supply 135 and the variable power supply 145 of the electroplating system 100 can be respectively corresponding variable voltage power supplies. In some specific implementations, the variable power supply 135 and the variable power supply 145 can be respectively corresponding variable current power supplies, for example, can respectively include variable current sources. In this example, corresponding plating voltage and / or plating current can be provided by the variable power supply 135 and the variable power supply 145. For example, the variable power supply 135 and the variable power supply 145 can be regulated respectively, or can be configured to provide corresponding plating current based on the corresponding area of ​​the plating surface of each side of the workpiece 125, for example, can be determined based on the ratio of the plating surface area of ​​each side of the workpiece 125.

[0044] For example, if the area of ​​the plateable surface on the left (bottom) side of the workpiece 125 is nine times the area of ​​the plateable surface on the right (top) side of the workpiece 125, the variable power supply 135 and the variable power supply 145 may be adjusted so that the plating current provided by the variable power supply 135 is nine times the plating current provided by the variable power supply 145, so that the current density (e.g., in A / dm2 ) is equal to or approximately equal to the current density of the plating current provided by the variable power supply 145 for plating the platable surface on the right (top) side of the workpiece 125. That is, in this example, the variable power supply 135 can be adjusted to provide 90% of the total plating current in the electroplating system 100, while the variable power supply 145 can be adjusted to provide 10% of the total plating current. It should be noted that the plating current provided by the variable power supply 135 and the variable power supply 145 can also plate the platable surface disposed between the left and right sides of the workpiece 125 (e.g., the edge of the lead frame strip of the workpiece 125).

[0045] In some implementations, variable power supply 135 and variable power supply 145 may be variable voltage power supplies, which are adjustable to provide a corresponding plating voltage between 0 volts and 24 volts (V). In some implementations, variable power supply 135 and variable power supply 145 may be variable current power supplies, which are adjustable to provide a corresponding plating current between 0 amperes and 150 amperes (A). In some implementations, variable power supply 135 and variable power supply 145 may be configured to allow adjustment of one or both of the provided voltage or the provided current.

[0046] Figure 2 2 is a diagram schematically illustrating another exemplary electroplating system 200. The electroplating system 200 includes similar components to the electroplating system 100. Figure 2 Chinese Figure 1 Therefore, for the sake of brevity, reference will no longer be made to Figure 2 These similar elements of the electroplating system 200 are described.

[0047] exist Figure 2 In the example of FIG. 1 , the electroplating system 200 further includes an anode terminal 230 and an anode terminal 250, which are disposed in the electrolytic plating solution 110 on a first side (left side or bottom side) of the workpiece 125 and the cathode terminal 120. The electroplating system 200 further includes an anode terminal 240 and an anode terminal 260, which are disposed in the electrolytic plating solution 110 on a second side (right side or top side) of the workpiece 125 and the cathode terminal 120 opposite to the first side.

[0048] like Figure 2As shown, variable power supply 235 is coupled between cathode terminal 120 and anode terminal 230, variable power supply 245 is coupled between cathode terminal 120 and anode terminal 240, variable power supply 255 is coupled between cathode terminal 120 and anode terminal 250, and variable power supply 265 is coupled between cathode terminal 120 and anode terminal 260. In this example, variable power supply 235 provides a plating current from anode terminal 230 to cathode terminal 120 for plating a first portion of a platable surface on the left side of workpiece 125. Similarly, variable power supply 255 provides a plating current from anode terminal 250 to cathode terminal 120 for plating a second portion of a platable surface on the left side of workpiece 125. For example, the plating current provided by the variable power supply 235 may affect the plating of the plateable surface of the upper half of the workpiece 125 on the left side of the workpiece 125, while the plating current provided by the variable power supply 255 may affect the plating of the plateable surface of the lower half of the workpiece 125 on the left side of the workpiece 125.

[0049] Similarly, the variable power supply 245 of the electroplating system 200 provides a plating current from the anode terminal 240 to the cathode terminal 120 for plating a first portion of the platable surface on the right side of the workpiece 125. Likewise, the variable power supply 265 provides a plating current from the anode terminal 260 to the cathode terminal 120 for plating a second portion of the platable surface on the right side of the workpiece 125. For example, the plating current provided by the variable power supply 245 may affect plating of the platable surface of the upper half of the workpiece 125 on the right side of the workpiece 125, while the plating current provided by the variable power supply 265 may affect plating of the platable surface of the lower half of the workpiece 125 on the right side of the workpiece 125. In electroplating system 200 , similar to electroplating system 100 , cathode terminal 120 is a common cathode terminal of anode terminal 230 , variable power supply 235 , anode terminal 240 , variable power supply 245 , anode terminal 250 , variable power supply 255 , anode terminal 260 , and variable power supply 265 .

[0050] In the electroplating system 200, the anode terminal 230 includes a base portion 230a and a soluble portion 230b disposed on the base portion 230a, the anode terminal 240 includes a base portion 240a and a soluble portion 240b disposed on the base portion 240a, the anode terminal 250 includes a base portion 250a and a soluble portion 250b disposed on the base portion 250a, and the anode terminal 260 includes a base portion 260a and a soluble portion 260b disposed on the base portion 260a. In this example, like the anode of the electroplating system 100, the base portion 230a, the base portion 240a, the base portion 250a, and the base portion 260a can be formed of a material having a low electrical resistance that is not easily consumed in the electrolytic plating solution 110, such as during electroplating of the workpiece 125. For example, in some implementations, the base portion of the anode terminal of the electroplating system 200 can include a corresponding titanium anode basket or an equivalent anode material.

[0051] The soluble portions 230b, 240b, 250b, and 260b may include solid plating metals, such as tin or other plating metals, that are soluble in the electrolytic plating solution 110. Thus, in this example, the soluble portions of the anode terminal are at least partially consumed during the electroplating of the workpiece 125. That is, the soluble portions of the anode terminal 230, 240, 250, and 260 provide consumable plating metals that are combined with plating metals that have been dissolved in the electrolytic plating solution 110 to plate the platable surfaces of the workpiece 125 (and / or other workpieces). Thus, at least the soluble portions 230b, 240b, 250b, and 260b of the anode terminal 230, 240, 250, and 260 will be replenished periodically, such as in a specific implementation of the electroplating system 200 used in a semiconductor device assembly manufacturing process. In some implementations, the base portions 230a, 240a, 250a, and 260a of the anode terminations 230, 240, 250, and 260 may also be replaced periodically, but less frequently than the soluble portions.

[0052] In some specific implementations, the variable power supply 235,245,255 and 265 of electroplating system 200 can be respectively corresponding variable voltage power supply. In some specific implementations, variable power supply 235,245,255 and 265 can be respectively corresponding variable current power supply, for example, can respectively include variable current source. In this example, corresponding plating voltage and / or plating current can be provided by variable power supply 235,245,255 and 265. For example, variable power supply 235,245,255 and 265 can be regulated respectively, or be configured to provide corresponding plating current based on the corresponding area of ​​plating surface of each side of workpiece 125.

[0053] For example, in this example, as in Figure 1In the example of FIG. 1 , if the area of ​​the plateable surface on the left (bottom) side of the workpiece 125 is nine times the area of ​​the plateable surface on the right (top) side of the workpiece 125, the variable power supplies 235 and 255 can be adjusted so that the combined plating current they provide (e.g., the plating current of the variable power supply 235 plus the plating current of the variable power supply 255) is nine times the combined plating current provided by the variable power supply 245 and the variable power supply 265. That is, the various variable power supplies of the electroplating system 200 can provide various plating currents so as to provide plating currents having equal or approximately equal current densities (e.g., in A / dm 2 The variable power supply 235 and the variable power supply 255 can be adjusted to provide 45% of the total plating current in the electroplating system 200, respectively, and the variable power supply 245 and the variable power supply 265 can be adjusted to provide 5% of the total plating current in the electroplating system 200. It should be noted that the plating current provided by the variable power supplies 235, 245, 255 and 265 can also plate the platable surface disposed between the left and right sides of the workpiece 125 (e.g., the edge of the lead frame strip of the workpiece 125).

[0054] In some implementations, variable power supplies 235, 245, 255 and 265 may be variable voltage power supplies, which are adjustable to provide a corresponding plating voltage between 0 volts and 24 volts (V). In some implementations, variable power supplies 235, 245, 255 and 265 may be variable current power supplies, which are adjustable to provide a corresponding plating current between 0 amperes and 100 amperes (A). In some implementations, variable power supplies 235, 245, 255 and 265 may each be configured to allow regulation of one or both of the voltage provided or the current provided.

[0055] Figure 3 is a diagram showing an exemplary block-molded semiconductor device assembly strip 300 viewed from a first side (e.g., top side). For example, the strip 300 can be a workpiece 125 of the electroplating system 100 and / or the electroplating system 200. Of course, the workpiece 125 can take other forms, such as other molded semiconductor device assembly strips, bare (e.g., unmolded) lead frames, one or more direct bonded metal substrates (e.g., with or without molded portions), etc.

[0056] exist Figure 3 , the view of the strip 300 may correspond to the right (top) side of the workpiece 125, as discussed above. Figure 1 and Figure 2As shown in the example of . For example, strip 300 includes lead frame strip 305, block molded portion 310a, block molded portion 310b and block molded portion 310c. In this example, each of block molded portions 310a-310c can each include a plurality of individual semiconductor device components, for example, in this example, each block molded portion has about nine hundred. For example, after performing electroplating on strip 300 using electroplating system 100 or electroplating system 200, these individual components can be singulated (separated, etc.) into individual semiconductor device components. Such singulation can be performed using a saw, a laser cutter, a plasma cutter, etc.

[0057] like Figure 3 As shown in , the exposed portions of the lead frame strip 305 disposed around the block molded portions 310a-310c can provide mechanical support for the individual lead frames of the strip 300, which are also separated from each other during the singulation process. Therefore, in this example, the exposed portions of the lead frame strip 305 are plateable surfaces, while the block molded portions 310a-310c are not plateable surfaces. In some specific implementations, during electroplating of the strip 300, the lead frame strip 305 can be electrically coupled to a cathode terminal of an electroplating system (such as, cathode terminal 120 of electroplating system 100 or electroplating system 200).

[0058] Reference now Figure 4 , showing the strip 300 and Figure 3 4. The side opposite to the (top) side shown in the view of FIG. 4 (eg, the bottom side) shows individual semiconductor components, for example, a single semiconductor component indicated by semiconductor component 400. Figure 5 , shows an exemplary pattern of a plateable surface of a semiconductor component 400. For example, Figure 5 The exemplary semiconductor component 400 shown includes signal pads 420a, 420b, 420c, 420d, 420e, 420f, 420g, and 420h, which may be portions of a lead frame (e.g., a copper lead frame) of the semiconductor component 400 included in the lead frame strip 305 that are exposed through the molding compound 410. Figure 4 As shown, the bottom side of the semiconductor component 400 also includes a die attach pad 425 , which may also be included in the lead frame of the semiconductor component 400 as part of the lead frame strip 305 .

[0059] Watch together Figure 4 and Figure 5, the plateable surface of the bottom side of the strip 300 includes the exposed portion of the lead frame strip 305 disposed around each of the block molded portions 310a-310c, and the signal pads 420a-420g and die attach pads 425 of each semiconductor component 400 (e.g., approximately 1800 individual semiconductor device components) of the strip 300. Thus, the area of ​​the plateable surface of the bottom side of the strip 300 (e.g., approximately 1800 individual semiconductor device components) is approximately 200 mm. Figure 4 ) is larger than the plateable surface area of ​​the top side of the strip 300 (as shown in Figure 3 1 and described above). For example, in an exemplary implementation, the ratio of the plateable surface area of ​​the bottom side to the plateable surface area of ​​the top side can be 9 to 1, or can have other ratios, such as 20 to 1, 15 to 1, 10 to 1, 7 to 1, 5 to 1, etc., depending on the specific implementation. Using the methods described herein, the plating of the plateable surface of the strip 300 can be affected using appropriate plating voltages and / or plating currents, and a plating thickness uniformity with a desired tolerance (e.g., a 10% variation or less) between the top side plateable surface and the bottom side plateable surface can be achieved.

[0060] Figure 6 is a flow chart showing an exemplary method 600 for electroplating. In this example, the method 600 may be performed by Figure 2 Therefore, for the purpose of illustration, further reference will be made to Figure 2 600. In other specific implementations, similar methods can be performed by electroplating systems with other configurations. For example, electroplating system 100 can implement a similar method, wherein the operations of frame 650 and frame 660 are omitted. In other specific implementations, additional operations can be added to method 600. For example, additional variable plating voltages and / or currents can be provided by additional variable power supplies. The specific operation of the electroplating method will depend at least in part on one or more of the workpiece being plated, the electroplating system used, and the surface area ratio of the platable surface on each side of the workpiece.

[0061] Figure 6The method 600 includes, at frame 610, coupling the workpiece 125 to the cathode terminal 120, for example, via the clamp 120a. At frame 620, the method 600 includes immersing the workpiece 125 in the electrolytic plating solution 110. The method 600 includes, at frame 630, providing a first plating current (e.g., from the variable power supply 235) from the anode terminal 230 for plating at least a first portion of the platable surface on the left side of the workpiece 125 (e.g., set to 50% of the total plating current to account for the clamping area being plated). The method 600 also includes, at frame 640, providing a second plating current (e.g., from the variable power supply 245) from the anode terminal 240 for plating at least a first portion of the platable surface on the right side of the workpiece 125 (e.g., set to 6% of the total plating current to account for the clamping area being plated). Method 600 also includes, at frame 650, providing a third plating current (e.g., from variable power supply 255) from anode terminal 250, for plating at least a second portion of the platable surface on the left side of workpiece 125 (e.g., set to 40% of total plating current). The method also includes, at frame 660, providing a fourth plating current (e.g., from variable power supply 265) from anode terminal 260, for plating at least a second portion of the platable surface on the right side of workpiece 125 (e.g., set to 4% of total plating current). As described herein, the plating current of the frames 630-660 of method 600 can be provided by changing the voltage and / or current of the corresponding variable power supply.

[0062] It should be understood that in the foregoing description, when an element such as a layer, region, substrate or component is mentioned as being on another element, connected to another element, electrically connected to another element, coupled to another element, or electrically coupled to another element, the element may be directly on another element, connected to or coupled to another element, or one or more intermediate elements may be present. On the contrary, when an element is mentioned as being directly on another element or layer, directly connected to another element or layer, or directly coupled to another element or layer, there is no intermediate element or layer. Although the term directly on, directly connected to, or directly coupled to may not be used throughout the specific embodiments, an element that is shown as being directly on an element, directly connected, or directly coupled can be mentioned in this manner. The claims of the present application (if any) may be revised to narrate the example relationships described in the specification or shown in the drawings.

[0063] As used in this specification and claims, unless the context clearly indicates a particular case, the singular may include the plural. In addition to the orientation shown in the drawings, spatial relative terms (e.g., on, above, above, below, below, below, below, etc.) are intended to cover different orientations of the device in use or operation. In some specific implementations, the relative terms above and below may include vertically above and vertically below, respectively. In some specific implementations, the term adjacent may include lateral adjacent or horizontal adjacent.

[0064] Some implementations may be implemented using various semiconductor processing and / or packaging technologies. Some implementations may be implemented using various types of semiconductor processing technologies associated with semiconductor substrates, including but not limited to, for example, silicon (Si), gallium arsenide (GaAs), gallium nitride (GaN), silicon carbide (SiC), etc.

[0065] Although certain features of the described implementations have been described as described herein, many modifications, alternatives, variations, and equivalents will now occur to those skilled in the art. Therefore, it should be understood that the appended claims are intended to cover all such modifications and variations that fall within the scope of the implementations. It should be understood that these modifications and variations are presented only by way of example and not limitation, and that various changes in form and detail may be made. In addition to mutually exclusive combinations, any portion of the apparatus and / or method described herein may be combined in any combination. The implementations described herein may include various combinations and / or sub-combinations of the functions, components, and / or features of the different implementations described.

Claims

1. An electroplating system (100, 200), the electroplating system comprising: Container (105); an electrolytic plating solution (110), the electrolytic plating solution being in the container; a cathode terminal (120) configured to be electrically connected to a workpiece (125) immersed in the electrolytic plating solution; a first anode terminal (130, 230) disposed in the electrolytic plating solution on a first side of the workpiece; a second anode terminal (140, 240) disposed in the electrolytic plating solution on a second side of the workpiece opposite the first side; a first variable power source (135, 235) coupled between the cathode terminal and the first anode terminal; and A second variable power source (145, 245) is coupled between the cathode terminal and the second anode terminal.

2. The electroplating system according to claim 1, wherein: The first variable power source comprises a first variable voltage power source; and The second variable power source includes a second variable voltage power source.

3. The electroplating system according to claim 1, wherein: The first variable power supply comprises a first variable current power supply; and The second variable power supply includes a second variable current power supply.

4. The electroplating system of claim 1, wherein the first anode terminal and the second anode terminal each comprise a solid plating material (130b, 230b) that is soluble in the electrolytic plating solution.

5. The electroplating system according to claim 1, wherein the electrolytic plating solution comprises: Methanesulfonic acid (MSA); and Liquid plating materials.

6. The electroplating system according to claim 1, further comprising: a third anode terminal (250) disposed in the electrolytic plating solution on the first side of the workpiece; a fourth anode terminal (260) disposed in the electrolytic plating solution on the second side of the workpiece; a third variable power supply (255) coupled between the cathode terminal and the third anode terminal; and A fourth variable power supply (265) is coupled between the cathode terminal and the fourth anode terminal.

7. The electroplating system of claim 6, wherein: The third variable power supply includes a first variable voltage power supply; and The fourth variable power supply includes a second variable voltage power supply.

8. The electroplating system of claim 6, wherein: The third variable power supply includes a first variable current power supply; and The fourth variable power supply includes a second variable current power supply.

9. The electroplating system of claim 1, wherein the workpiece is a strip (300) of bulk molded semiconductor device components.

10. The electroplating system of claim 1, wherein: The first variable power supply is configured to provide a first plating current based on an area of ​​at least one plateable surface of the first side of the workpiece; and The second variable power supply is configured to provide a second plating current based on an area of ​​at least one plateable surface of the second side of the workpiece.

11. The electroplating system of claim 1, wherein: The first variable power source is configured to provide a first plating current for plating at least one plateable surface of the first side of the workpiece at a current density; and The second variable power supply is configured to provide a second plating current for plating at least one plateable surface of the second side of the workpiece at the current density.

12. A method (600), comprising: electrically coupling (610) the workpiece (125) to a common cathode terminal (120) of the electroplating system (100, 200); immersing (620) the workpiece in an electrolytic plating solution (110); supplying (630) a first plating current from a first anode terminal (130, 230) immersed in the electrolytic plating solution for electroplating at least one plateable surface of a first side of the workpiece; as well as A second plating current is supplied (640) from a second anode terminal (140, 240) immersed in the electrolytic plating solution for electroplating at least one plateable surface of a second side of the workpiece, the second plating current being different from the first plating current, the second side of the workpiece being opposite to the first side of the workpiece.

13. The method of claim 12, wherein the workpiece is a strip (300) of bulk molded semiconductor device assemblies.

14. The method of claim 12, wherein: The first plating current is based on an area of ​​the at least one plateable surface of the first side of the workpiece; and The second plating current is based on an area of ​​the at least one plateable surface of the second side of the workpiece.

15. The method of claim 12, wherein the first plating current is used to plate a first portion of the at least one plateable surface of the first side of the workpiece, and the second plating current is used to plate a first portion of the at least one plateable surface of the second side of the workpiece, The method further comprises: supplying (650) a third plating current from a third anode terminal (250) immersed in the electrolytic plating solution for electroplating a second portion of the at least one plateable surface of the first side of the workpiece; as well as A fourth plating current is supplied (660) from a fourth anode terminal (260) immersed in the electrolytic plating solution for electroplating a second portion of the at least one plateable surface of the second side of the workpiece.

16. The method of claim 15, wherein: The third plating current is different from the first plating current; and The fourth plating current is different from the second plating current.

17. The method of claim 15, wherein: The third plating current is equal to the first plating current; and The fourth plating current is equal to the second plating current.

18. The method of claim 15, wherein: The third plating current is equal to the first plating current; and The fourth plating current is different from the second plating current.

19. An electroplating system (200), comprising: Container (105); an electrolytic plating solution (110), the electrolytic plating solution being in the container and comprising a liquid plating material; a common cathode terminal (120) configured to be electrically connected to a workpiece (125) immersed in the electrolytic plating solution; a first anode terminal (230) disposed in the electrolytic plating solution on a first side of the workpiece; a second anode terminal (240) disposed in the electrolytic plating solution on the first side of the workpiece; a third anode terminal (250) disposed in the electrolytic plating solution on a second side of the workpiece opposite the first side; a fourth anode terminal (260) disposed in the electrolytic plating solution on the second side of the workpiece; a first variable power source (235) coupled between the common cathode terminal and the first anode terminal; a second variable power source (245) coupled between the common cathode terminal and the second anode terminal; a third variable power supply (255) coupled between the common cathode terminal and the third anode terminal; and A fourth variable power supply (265) is coupled between the common cathode terminal and the fourth anode terminal.

20. The electroplating system of claim 19, wherein: The first variable power supply comprises a first variable voltage power supply; The second variable power supply includes a second variable voltage power supply; The third variable power supply comprises a third variable voltage power supply; and The fourth variable power supply includes a fourth variable voltage power supply.

21. The electroplating system of claim 19, wherein: The first variable power supply includes a first variable current power supply; The second variable power supply includes a second variable current power supply; The third variable power supply comprises a third variable current power supply; and The fourth variable power supply includes a fourth variable current power supply.

22. The electroplating system of claim 19, wherein the workpiece is a strip (300) of bulk molded semiconductor device components.

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