Surface treatment device and method for bonding wire processing

Abstract

The invention provides a surface treatment device and method for bonding wire processing, and relates to the field of bonding wire processing. The surface treatment device for bonding wire machining comprises continuously-distributed groove bodies, a grinding mechanism is arranged in one groove body, a polishing mechanism is arranged in the groove body located in the next procedure of the grinding mechanism, a winding mechanism is arranged in the groove body for electroplating, the grinding mechanism comprises a flow channel, a spraying hole pointing to the center of the flow channel is formed in the flow channel, and the spraying hole is communicated with the spraying hole. The outer side of the flow channel is connected with and penetrates through a sand blasting pump which extracts grinding fluid from the groove body and sprays the grinding fluid out of the flow channel, the polishing mechanism comprises supports which are symmetrically arranged in the groove body, and polishing cotton is arranged between the two supports. According to the surface treatment device for bonding wire processing, after polishing is completed, follow-up processes can be completed under the liquid level, and through the arrangement, air can be isolated, and the situation that the polished bonding wire is oxidized, and the conductivity is reduced can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of bonding wire processing, and in particular to a surface treatment device and method for bonding wire processing. Background Art

[0002] Bonding wire is one of the five important structural materials for semiconductor packaging. It refers to the fine metal wire that uses wire bonding technology to achieve electrical connection between the connection points (bonding points) of the circuit inside the chip and the internal contact points of the lead frame when assembling semiconductor devices and integrated circuits.

[0003] CN102181898B is an online pre-treatment device for copper plating on the surface of stainless steel wire, belonging to the field of electroplating technology. It includes an acid pickling tank (1), a water washing tank (2) and a sealed container (3). The top of the water washing tank (2) is closed and provided with an air inlet (5). The upper part is provided with a plurality of spray ports (7). The lower part is divided into a plurality of areas. The liquid level in the first area is the lowest and the liquid level in the last area is the highest. The number of spray ports (7) is equal to the number of stepped areas. The upper part of the first area is provided with an overflow port (9), the bottom is provided with a water outlet (10), and the upper part of the last area is provided with a water inlet (8). The sealed container (3) is connected to the outlet of the water washing tank (2). The sealed container (3) is provided with an air outlet (6), and the air outlet (6) is located above the electroplating liquid level. The online pre-treatment device for copper-plated stainless steel wire can obtain a thick and stable copper plating layer, effectively improves the bonding strength between the plating layer and the substrate, and the water consumption of the water washing tank is also small. Since the diameter of the bonding wire is smaller and the surface area is larger after drawing, it is easier to form an oxide layer on the surface, thereby affecting the conductive efficiency. Therefore, a processing device and method that can avoid and reduce the oxidation of the bonding wire is needed. Summary of the Invention

[0004] In view of the deficiencies in the prior art, the present invention provides a surface treatment device and method for bonding wire processing, which solves the problem of easy oxidation of bonding wires mentioned in the above background technology.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A surface treatment method for bonding wire processing, comprising the following steps:

[0006] S1, performing preliminary cleaning of the bonding wire in the corresponding tank, including a combination of acid cleaning, alkaline cleaning, and clean water cleaning, and finally performing clean water cleaning;

[0007] S2, grinding and underwater polishing of the bonding wire;

[0008] S3, re-washing the bonding wire below the liquid level in the corresponding tank, including the initial and final water washes and the intermediate acid washes, alkaline washes, and water washes in alternating combinations;

[0009] S4, activating the bonding wire below the liquid level in the tank;

[0010] S5, rolling up all bonding wires into the electroplating tank and then electroplating;

[0011] S6, performing post-electroplating treatment on the bonding wire.

[0012] Preferably, during the process of steps 2 to 5, a protective device is provided between adjacent troughs to protect the bonding wires from contact with oxygen.

[0013] A surface treatment device for bonding wire processing is used for bonding wire surface treatment, comprising continuously distributed troughs, one of which is provided with a grinding mechanism, a trough located in the next process of the grinding mechanism is provided with a polishing mechanism, and a trough for electroplating is provided with a winding mechanism.

[0014] Preferably, the grinding mechanism includes a flow channel, a spray hole pointing to the center of the flow channel is opened inside the flow channel, the outside of the flow channel is connected to and penetrates a sandblasting pump that extracts grinding fluid from the tank body and sprays it from the flow channel, and the polishing mechanism includes symmetrically arranged brackets arranged in the tank body, polishing cotton is arranged between the two brackets, the polishing cotton is sleeved on the outer surface of the passing bonding wire, and an extrusion part is provided on the outside of the polishing cotton to squeeze the polishing cotton inward.

[0015] Preferably, there are at least four flow channels, and one side of the flow channel is kept in contact with the bonding wire with the bonding wire passing through as the center, and no spray hole is provided on the contact surface.

[0016] Preferably, support frames are provided in the tank bodies other than the electroplated tank body, telescopic parts are equidistantly provided at both ends of the support frame, guide wheels are provided at the free ends of the telescopic parts, and reversing wheels for pressing the bonding wire into the liquid are provided below the inner ends of the tank body.

[0017] Preferably, the protection device includes a transition groove arranged between two adjacent trough bodies, a through hole located below the liquid level is opened between the transition groove and the two adjacent trough bodies, and a discharge pump for extracting liquid outward is provided at the bottom end of the transition groove.

[0018] Preferably, the protection device includes a U-shaped tube arranged between two adjacent troughs, both ends of the U-shaped tube extend below the liquid level of the corresponding trough, the bonding wire passes through the U-shaped tube, and an injection mechanism for injecting protective gas into the U-shaped tube is provided above the U-shaped tube.

[0019] Preferably, a nozzle is provided inside the tank body, and a protective gas is introduced into the nozzle and sprayed outward.

[0020] Preferably, the tank body used for electroplating is divided into an electroplating tank and a pre-plating tank. The winding mechanism is arranged inside the pre-plating tank. The winding mechanism includes a winding wheel arranged below the liquid surface and a power mechanism located above the liquid surface to drive the winding wheel to rotate. The winding wheel and the transmission part of the power mechanism are both made of insulating materials. An insulating partition is provided between the pre-plating tank and the transition tank to block the flow of liquid. Compared with the existing technology, the present invention has the following advantages:

[0021] 1. The surface treatment device method for bonding wire processing can set the subsequent processes below the liquid level after polishing is completed. This setting can isolate the air to prevent the bonding wire from being oxidized and reducing its conductivity after polishing.

[0022] 2. The surface treatment device for bonding wire processing, the protective device includes a U-shaped tube arranged between two adjacent troughs, both ends of the U-shaped tube extend below the liquid level of the corresponding trough, the bonding wire passes through the U-shaped tube, and an injection mechanism for injecting protective gas into the U-shaped tube is provided above the U-shaped tube. By setting up the injection mechanism, protective gas can be injected into the U-shaped tube to exhaust the air, thereby preventing the bonding wire passing through from being oxidized, and the injected protective gas is discharged from both ends.

[0023] 3. The surface treatment device for bonding wire processing has at least four flow channels. The flow channels keep one side in contact with the bonding wire with the passing bonding wire as the center and no spray holes are provided on the contact surface. By setting up multiple groups of flow channels and not providing spray holes in the supporting parts, the bonding wire can be supported during the sandblasting process to avoid breakage of the bonding wire due to external forces.

[0024] 4. The surface treatment device for bonding wire processing, the tank body for electroplating is divided into an electroplating tank and a pre-plating tank, the winding mechanism is arranged inside the pre-plating tank, the winding mechanism includes a winding wheel arranged below the liquid surface, and a power mechanism located above the liquid surface for driving the winding wheel to rotate, the winding wheel is plugged into the power mechanism, the winding wheel and the transmission part in the power mechanism are all made of insulating materials, through this arrangement, the winding mechanism can be prevented from being electroplated, an insulating partition for closing the liquid flow is provided between the pre-plating tank and the transition tank, through this arrangement, the electroplating liquid and other liquids can be separated during the electroplating process to avoid leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the connection of the sandblasting pump of the present invention;

[0027] Figure 3 This is a schematic diagram of the flow channel connection of the present invention;

[0028] Figure 4This is a schematic diagram of the U-shaped tube connection of the present invention;

[0029] Figure 5 This is a schematic diagram of the transition trough connection of the present invention;

[0030] Figure 6 This is a schematic diagram of the connection of the polishing mechanism of the present invention;

[0031] Figure 7 This is a schematic diagram of the connection of the electroplating tank of the present invention.

[0032] In the figure: 1. trough body; 2. grinding mechanism; 3. polishing mechanism; 4. winding mechanism; 201. flow channel; 202. spray hole; 203. sandblasting pump; 301. bracket; 302. polishing cotton; 33. extrusion part; 501. support frame; 502. telescopic part; 503. guide wheel; 504. reversing wheel; 601. transition trough; 602. through hole; 603. discharge pump; 604. U-shaped tube; 605. injection mechanism; 7. nozzle; 101. electroplating tank; 102. pre-plating tank; 103. insulating partition; 401. winding wheel; 402. power mechanism. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0034] It should be noted that all directional indications in the embodiments of the present application are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0035] In this application, unless otherwise specified or limited, the terms "connection" and "fixation" should be understood in a broad sense. For example, "fixation" can mean fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0036] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0037] like Figure 1-7 As shown, a surface treatment device for bonding wire processing is used for surface treatment of bonding wire, including continuously distributed troughs 1, wherein a grinding mechanism 2 is provided in one of the troughs 1, a polishing mechanism 3 is provided in the trough 1 located in the next process of the grinding mechanism 2, and a winding mechanism 4 is provided in the trough 1 used for electroplating.

[0038] The grinding mechanism 2 includes a flow channel 201, and a spray hole 202 pointing to the center of the flow channel 201 is opened inside the flow channel 201. The outside of the flow channel 201 is connected to and penetrated by a sandblasting pump 203 that extracts grinding fluid from the tank body 1 and sprays it from the flow channel 201. The polishing mechanism 3 includes a bracket 301 symmetrically arranged in the tank body 1, and polishing cotton 302 is arranged between the two brackets 301. The polishing cotton 302 is sleeved on the outer surface of the passing bonding wire. The outside of the polishing cotton 302 is provided with an extrusion part 33 for squeezing the polishing cotton 302 inward. The extrusion part 33 can be a pressure plate for adjusting the contact surface, or a cable tie ring can be used. Wet sandblasting is adopted to use the flowing sandblasting sand to impact the bonding wire, which can remove burrs on the surface of the bonding wire.

[0039] There are at least four flow channels 201, and the flow channels 201 keep one side in contact with the bonding wire with the passing bonding wire as the center, and no spray hole 202 is provided on the contact surface. By setting multiple groups of flow channels 201 and not providing spray holes 202 at the supporting parts, the bonding wire can be supported during the sandblasting process to avoid breakage of the bonding wire due to external force.

[0040] Except for the electroplated tank body 1, other tank bodies 1 are provided with support frames 501, and telescopic parts 502 are equidistantly provided at both ends of the support frame 501. The free end of the telescopic part 502 is provided with a guide wheel 503, and a reversing wheel 504 for pressing the bonding wire into the liquid is provided below the inner ends of the tank body 1. The extended length of the guide wheel 503 is adjusted by the telescopic part 502, thereby changing the residence time of the bonding wire in the corresponding tank body 1.

[0041] The protective device includes a transition groove 601 arranged between two adjacent trough bodies 1. A through hole 602 located below the liquid level is provided between the transition groove 601 and the two adjacent trough bodies 1. A discharge pump 603 for extracting liquid is provided at the bottom end of the transition groove 601. The corresponding trough body 1 should be provided with a liquid replenishing device so that the corresponding liquid level is always located above the through hole 602. By providing the discharge pump 603, the mixed liquid can be extracted outward, so that the liquid in the corresponding trough body 1 can flow out, reducing the possibility of mixing with the liquid in the adjacent trough body 1.

[0042] The protection device includes a U-shaped tube 604 arranged between two adjacent trough bodies 1. Both ends of the U-shaped tube 604 extend below the liquid level of the corresponding trough body 1. The bonding wire passes through the U-shaped tube 604. An injection mechanism 605 is provided above the U-shaped tube 604 for injecting protective gas into the U-shaped tube 604. By setting the injection mechanism 605, protective gas can be injected into the U-shaped tube 604 to exhaust the air, thereby preventing the bonding wire passing through from being oxidized, and the injected protective gas is discharged from both ends.

[0043] A nozzle 7 is provided inside the tank body 1, and a protective gas is introduced into the nozzle 7 and sprayed outward. By adding the nozzle 7, the flow of the liquid can be accelerated. At the same time, the provision of the protective gas can avoid increasing the oxygen content in the liquid. The protective gas is nitrogen or inert gas.

[0044] The tank body 1 used for electroplating is divided into an electroplating tank 101 and a pre-plating tank 102. The winding mechanism 4 is arranged inside the pre-plating tank 102. The winding mechanism 4 includes a winding wheel 401 arranged below the liquid surface, and a power mechanism 402 located above the liquid surface for driving the winding wheel 401 to rotate. The winding wheel 401 is plugged into the power mechanism 402. The winding wheel 401 and the transmission part in the power mechanism 402 are all made of insulating materials. Through such an arrangement, the winding mechanism 4 can be prevented from being electroplated. An insulating partition 103 for closing the liquid flow is provided between the pre-plating tank 102 and the transition tank 601. Through such an arrangement, the electroplating liquid and other liquids can be separated during the electroplating process to avoid leakage.

[0045] The following steps are involved:

[0046] S1, performing preliminary cleaning of the bonding wire in the corresponding tank, including a combination of acid cleaning, alkaline cleaning, and clean water cleaning, and finally performing clean water cleaning;

[0047] S2, grinding and underwater polishing of the bonding wire;

[0048] S3, re-washing the bonding wire below the liquid level in the corresponding tank, including the initial and final water washes and the intermediate acid washes, alkaline washes, and water washes in alternating combinations;

[0049] S4, activating the bonding wire below the liquid level in the tank, through mild corrosion or electrochemical action, making the metal surface micro-rough (increasing the surface area), or forming active sites to promote the reduction and deposition of metal ions on the surface during electroplating;

[0050] S5, after all bonding wires are rolled up into the electroplating tank, electroplating is performed. During this process, the concentration of the electroplating solution needs to be increased. Since the transition tank continuously discharges liquid, the electroplating solution only serves to isolate oxygen in the initial process. Therefore, a low-concentration electroplating solution or clean water is placed in the electroplating tank during this process. When electroplating is required, the clean water or low-concentration electroplating solution is extracted, but the liquid level is kept above the bonding wires. Then, a high-concentration electroplating solution is added for electroplating. In particular, when multi-layer electroplating is required, after the first layer of electroplating is completed, the bonding wires can be exposed to air before the next layer of electroplating is performed.

[0051] S6, perform post-electroplating treatment on the bonding wire to remove residual plating solution, activator or other impurities on the surface of the coating to prevent subsequent corrosion or contamination, and perform heat treatment to eliminate stress within the coating and improve hardness and wear resistance.

[0052] Through this treatment process, after polishing is completed, subsequent processes can be set below the liquid level. This setting can isolate the air to prevent the bonding wire from being oxidized and reducing its conductivity after polishing.

[0053] During steps 2 to 5, a protective device is provided between adjacent troughs to protect the bonding wires from contact with oxygen.

[0054] During use, the bonded wire formed by drawing is subjected to preliminary cleaning to remove lubricating liquid and stains on the surface. Alkaline washing is required with alkaline solution (such as sodium hydroxide, sodium carbonate) or surfactant to remove oil stains through saponification reaction (for animal and vegetable oils) or emulsification (for mineral oils). The surface is then cleaned with clean water and pickled again. Hydrochloric acid and sulfuric acid solutions are used to remove the oxide scale, and then clean water is used to remove the pickling solution.

[0055] Then, the raised burrs on the surface of the bonding wire are polished by wet sandblasting to remove the tip, and then the bonding wire is inserted into the liquid and polished by the polishing mechanism 3;

[0056] The bonding wire is cleaned again by a combination of pickling, water washing and alkaline washing. The cleaning time of this process is longer than the initial cleaning time.

[0057] It is activated through the activation tank and rolled up as a whole into the pre-plating tank.

[0058] After all bonding wires are wound into the pre-plating tank, a partition is inserted between the pre-plating tank and the transition tank to block the flow of liquid and maintain insulation, and the bonding wires are guided into the electroplating tank for electroplating.

[0059] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0060] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0061] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A surface treatment method for bonding wire processing, characterized in that: The following steps are involved: S1, performing preliminary cleaning of the bonding wire in the corresponding tank, including a combination of acid cleaning, alkaline cleaning, and clean water cleaning, and finally performing clean water cleaning; S2, grinding and underwater polishing of the bonding wire; S3, re-washing the bonding wire below the liquid level in the corresponding tank, including the initial and final water washes and the intermediate acid washes, alkaline washes, and water washes in alternating combinations; S4, activating the bonding wire below the liquid level in the tank; S5, rolling up all bonding wires into the electroplating tank and then electroplating; S6, performing post-electroplating treatment on the bonding wire.

2. The surface treatment method for bonding wire processing according to claim 1, characterized in that: During steps 2 to 5, a protective device is provided between adjacent troughs to protect the bonding wires from contact with oxygen.

3. A surface treatment device for bonding wire processing, characterized in that: The bonding wire surface treatment device according to claim 2 comprises continuously distributed trough bodies (1), wherein a grinding mechanism (2) is provided in one of the trough bodies (1), a polishing mechanism (3) is provided in the trough body (1) located in the next process of the grinding mechanism (2), and a winding mechanism (4) is provided in the trough body (1) used for electroplating.

4. The surface treatment device for bonding wire processing according to claim 3, characterized in that: The polishing mechanism (2) comprises a flow channel (201), a spray hole (202) pointing to the center of the flow channel (201) is opened inside the flow channel (201), and a sandblasting pump (203) is connected to and penetrates the outside of the flow channel (201) for extracting polishing fluid from the tank body (1) and spraying it out of the flow channel (201); The polishing mechanism (3) comprises symmetrical brackets (301) arranged in the tank body (1), polishing cotton (302) is arranged between the two brackets (301), the polishing cotton (302) is sleeved on the outer surface of the passing bonding wire, and an extrusion portion (33) is arranged on the outer side of the polishing cotton (302) for extruding the polishing cotton (302) inward.

5. The surface treatment device for bonding wire processing according to claim 4, characterized in that: There are at least four flow channels (201), and the flow channels (201) keep one side in contact with the bonding wire with the bonding wire passing through as the center, and no spray hole (202) is provided on the contact surface.

6. A surface treatment device for bonding wire processing according to claims 3-5, characterized in that: A support frame (501) is provided in the other tank bodies (1) except the electroplated tank body (1), telescopic parts (502) are equidistantly provided at both ends of the support frame (501), a guide wheel (503) is provided at the free end of the telescopic part (502), and a reversing wheel (504) for pressing the bonding wire into the liquid is provided below the two ends of the tank body (1).

7. The surface treatment device for bonding wire processing according to claim 6, characterized in that: The protection device comprises a transition groove (601) arranged between two adjacent groove bodies (1); a through hole (602) located below the liquid level is provided between the transition groove (601) and the two adjacent groove bodies (1); and a discharge pump (603) for extracting liquid is provided at the bottom end of the transition groove (601).

8. The surface treatment device for bonding wire processing according to claim 6, characterized in that: The protection device comprises a U-shaped tube (604) arranged between two adjacent tank bodies (1), with both ends of the U-shaped tube (604) extending below the liquid level of the corresponding tank body (1), the bonding wire passing through the U-shaped tube (604), and an injection mechanism (605) for injecting protective gas into the U-shaped tube (604) being arranged above the U-shaped tube (604).

9. A surface treatment device for bonding wire processing according to claim 7 or 8, characterized in that: A spray head (7) is provided inside the tank body (1), and a protective gas is introduced into the spray head (7) and sprayed outward.

10. The surface treatment device for bonding wire processing according to claim 9, characterized in that: The tank body (1) used for electroplating is divided into an electroplating tank (101) and a pre-plating tank (102). A winding mechanism (4) is arranged inside the pre-plating tank (102). The winding mechanism (4) comprises a winding wheel (401) arranged below the liquid surface, and a power mechanism (402) located above the liquid surface for driving the winding wheel (401) to rotate. The winding wheel (401) and the transmission parts in the power mechanism (402) are both made of insulating materials. An insulating partition (103) for sealing the flow of liquid is arranged between the pre-plating tank (102) and the transition tank (601).

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