Pickling device for single crystal copper bonding wire

Abstract

The invention discloses a single crystal copper bonding wire pickling device which comprises a plurality of pickling units, the pickling units are coaxially and sequentially spliced to form the pickling device, each pickling unit comprises a pickling box, positioning mechanisms are arranged at the centers of the two ends of the pickling box, and an arc-shaped hollow plate is rotationally connected to the inner wall of the pickling box; the top of the arc-shaped hollow plate is provided with a plurality of output pipes which are communicated with external feeding equipment, the inner wall of the arc-shaped hollow plate is communicated and connected with a plurality of staggered output pipes, and the multiple output pipes are symmetrically arranged in a cross section manner; the pickling unit further comprises a gravity deflection mechanism, and in the pickling stage, the gravity deflection mechanism drives the arc-shaped hollow plate to periodically rotate in a reciprocating mode in the inner wall of the pickling box, so that the axial angle of the output pipe for flushing the bonding wire is adjusted. According to the invention, the stages of peracid, washing and drying can be realized through a plurality of continuous and same pickling units, the bonding wire does not need to be bent in the whole pickling process, the damage probability of the bonding wire is reduced, and the pickling effect is good.

Description

Technical Field

[0001] The invention belongs to the technical field of bonding wire processing equipment, and in particular relates to a single crystal copper bonding wire pickling device. Background Art

[0002] Single crystal copper bonding wire is a metal wire used in semiconductor packaging. Single crystal copper means that the crystal structure of copper is continuous and has no grain boundaries. The single crystal structure makes copper wire superior to polycrystalline copper in terms of mechanical strength, electrical conductivity and corrosion resistance; single crystal copper bonding wire is usually used for electrical connections of microelectronic chips and other electronic components. Compared with traditional polycrystalline copper or bonding wires made of other materials, single crystal copper has higher electrical conductivity, better mechanical strength and better thermal conductivity, and therefore is gradually favored in high-performance semiconductors and microelectronic devices.

[0003] In the production process of tin-plated single-crystal copper bonding wire, pickling is a crucial step. Copper is easily oxidized in the air to form a copper oxide layer, which is not conducive to the quality of tin plating. Pickling before tin plating can remove these oxide layers, ensuring that the tin layer can directly contact the copper metal during tin plating, thereby improving weldability and bonding reliability; on the surface of the copper wire, there may be organic pollutants such as lubricating oil and fingerprints. Pickling can effectively remove these pollutants to prevent them from affecting the chemical reaction during the tin plating process, thereby ensuring the uniformity and adhesion of the tin layer; in addition, pickling can also remove some impurities such as scale and stains on the copper surface, ensuring that the copper surface before tin plating reaches the best clean state, which helps to evenly cover the tin plating layer.

[0004] Pickling includes three stages: pickling, rinsing and drying. Pickling is to remove oxides, lubricating oils and pollutants on the surface of the bonding wires through pickling liquid. After the pickling is completed, the bonding wires need to be rinsed again with clean water to remove the pickling liquid on the surface to prevent the pickling liquid from corroding the bonding wires. Finally, the moisture on the surface of the bonding wires is dried.

[0005] In the prior art, three different equipments are required for the three stages of pickling, and the over-acid equipment is as follows: Figure 1 As shown, the bonding wire needs to be pressed into the acid pool by a pressing roller. However, due to the small diameter and high hardness of the bonding wire, the bonding wire is easily damaged in the process of being pressed and deformed by the pressing roller, which affects subsequent use. Summary of the invention

[0006] The present invention aims at solving the problems in the prior art and proposes the following technical solutions:

[0007] A single crystal copper bonding wire pickling device comprises a plurality of pickling units, wherein the plurality of pickling units are coaxially assembled in sequence to form the pickling device, wherein the pickling units comprise a pickling box, wherein positioning mechanisms are arranged at the center of both ends of the pickling box, wherein an arc-shaped hollow plate is rotatably connected to the inner wall of the pickling box, wherein a plurality of output pipes arranged in a staggered manner are mutually connected to the inner wall of the arc-shaped hollow plate, and wherein the plurality of output pipes are arranged symmetrically in cross section;

[0008] The pickling unit also includes a gravity deflection mechanism, which drives the arc-shaped hollow plate to periodically reciprocate in the inner wall of the pickling box during the pickling stage, thereby adjusting the axial angle of the output pipe flushing bonding line.

[0009] As a preferred embodiment of the above technical solution, the pickling solution uses tin-plating flux, and the ratio of tin-plating flux to industrial soft water is 1:3.

[0010] As a preferred embodiment of the above technical solution, a feed discharge port is provided at the bottom of the pickling box, and a ground foot is fixedly connected to the outer side of the bottom of the pickling box, and the ground foot makes the feed discharge port suspended.

[0011] As a preferred embodiment of the above technical solution, the outer wall of the pickling box is provided with a guide assembly, and the guide assembly includes a guide sleeve and a guide rod. When a plurality of the pickling units are coaxially assembled in sequence, the guide sleeve and the guide rod on the adjacent pickling units are axially butted.

[0012] As a preferred embodiment of the above technical solution, the gravity deflection mechanism includes an arc-shaped extension plate and a counterweight block respectively arranged on the lower edges of both sides of the arc-shaped hollow plate, and the arc-shaped extension plate is in contact with the inner wall of the pickling box, the lower edge of the arc-shaped extension plate is fixedly connected with an upper hook plate, and the two ends of the arc-shaped extension plate and the upper hook plate are jointly fixedly connected with side sealing plates, and the arc-shaped extension plate, the upper hook plate and the side sealing plates are combined to form a liquid storage tank; a leakage hole is opened at the lower edge of the arc-shaped extension plate.

[0013] As a preferred embodiment of the above technical solution, a vertical plate is fixedly connected to the bottom inner wall of the pickling box, a first magnetic block is arranged on the side of the vertical plate close to the upper hook plate, a second magnetic plate is fixedly connected to the top of the upper hook plate, and the second magnetic plate corresponds to the first magnetic block and magnetically repels each other.

[0014] As a preferred embodiment of the above technical solution, the output pipe includes a tube body, a tube body cavity connected to the arc-shaped hollow plate is arranged inside the tube body; a nozzle with a conical cross-section is arranged at one end of the tube body away from the arc-shaped hollow plate, a nozzle cavity is arranged inside the nozzle, the tail end of the nozzle cavity is connected to the tube body cavity, and the tip of the nozzle cavity is facing the bonding line in the center of the inner cavity of the pickling box.

[0015] As a preferred embodiment of the above technical solution, the said one includes one which is interconnected with the top of the arc-shaped hollow plate, and is provided on it, and the said top is installed with.

[0016] As a preferred embodiment of the above technical solution, a plurality of guide grooves are provided on the top of the pickling box, and the width of the guide grooves is matched with the outer diameter of the pickling box.

[0017] As a preferred embodiment of the above technical solution, a center hole for accommodating a positioning mechanism is provided at the center of both ends of the pickling box, and the positioning mechanism includes a plurality of leg rods fixedly connected to the inner wall of the center hole, and one end of the plurality of leg rods close to each other is commonly fixedly connected to a frame plate, and a soft pad is detachably installed at the center of the frame plate, and a positioning through hole matching the diameter of the bonding wire is provided at the center of the soft pad.

[0018] The beneficial effects of the present invention are:

[0019] 1. The pickling unit in the present invention can not only realize the over-acidification of the bonding wire, but also realize the rinsing and drying of the bonding wire. The functionality of the pickling unit is wide. During the pickling operation, multiple pickling units can be coaxially assembled and used in sequence; multiple continuous pickling units can also be used to realize the single stages of over-acidification, rinsing, and drying, thereby achieving better stage effects and being used to adapt to different pickling requirements of the bonding wire; and there is no need to bend the bonding wire during the entire pickling process, thereby reducing the probability of damage to the bonding wire.

[0020] 2. When the pickling unit for over-acidification and flushing is being rinsed, since the output pipes in the inner cavity of the pickling tank are staggered and arranged symmetrically in cross section, the pickling liquid / clean water sprayed on one side will flow along the inner wall of the arc-shaped hollow plate to the liquid storage tank. This is the liquid storage stage. As more and more liquid is stored in the liquid storage tank, the arc-shaped hollow plate and the output pipe are driven to rotate along the inner wall of the pickling tank as a whole, and then rotate to the liquid discharge stage. In this stage, the leakage hole and the discharge port coincide, and the liquid in the liquid storage tank flows out from the leakage hole and the discharge port, and the second magnetic plate gradually approaches the first magnetic plate. Since the first magnetic block and the second magnetic plate magnetically repel each other, the arc hollow plate, the output pipe, the liquid storage tank and other components gradually slow down their rotation as a whole; when the liquid in the liquid storage tank gradually decreases to a certain level, under the joint action of the magnetic repulsion of the first magnetic block and the second magnetic plate and the gravity of the counterweight block, the arc hollow plate, the output pipe and other components are driven to rotate in the opposite direction to the liquid storage stage as a whole, and reciprocate in this way. During the reciprocating rotation, the axial angle of the output pipe for flushing the bonding line can be reciprocated to obtain better peracidification and flushing effects on the bonding line. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 What is shown is a schematic diagram of acid overload of single crystal copper bonding wire in the prior art;

[0022] Figure 2 What is shown is a schematic diagram of the three-dimensional structure of the pickling unit in the pickling device for single crystal copper bonding wire in the embodiment;

[0023] Figure 3What is shown is a schematic diagram of the three-dimensional structure of a single crystal copper bonding wire pickling device in an embodiment;

[0024] Figure 4 The figure shows the internal structure of the pickling box of the liquid storage tank in the pickling device for single crystal copper bonding wire in the embodiment during the water storage stage;

[0025] Figure 5 The figure shows the internal structure of the pickling box of the liquid storage tank in the pickling device for single crystal copper bonding wire in the embodiment during the water discharge stage;

[0026] Figure 6 What is shown is a schematic diagram of the three-dimensional structure of the arc-shaped hollow plate in the single crystal copper bonding wire pickling device in the embodiment;

[0027] Figure 7 What is shown is a schematic diagram of the internal structure of the output tube in the single crystal copper bonding wire pickling device in the embodiment;

[0028] Figure 8 It is shown that Figure 2 Enlarged view of point A in the middle.

[0029] In the figure: 10, pickling box; 11, foot; 12, guide groove; 131, guide sleeve; 132, guide rod; 14, center hole; 15, positioning mechanism; 151, leg rod; 152, frame plate; 153, cushion; 154, positioning perforation; 16, feed opening; 20, arc hollow plate; 21, output pipe; 211, tube body; 2110, tube body cavity; 212, nozzle; 2120, nozzle cavity; 30, gravity deflection mechanism; 31, vertical plate; 311, first magnetic block; 32, arc extension plate; 321, leakage hole; 33, upper hook plate; 34, second magnetic plate; 35, counterweight block; 36, side sealing plate. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments.

[0031] Example

[0032] like Figure 2 , Figure 3 As shown, the single crystal copper bonding wire pickling device includes a plurality of pickling units, and the plurality of pickling units are coaxially assembled in sequence to form a pickling device. The pickling unit in the present invention can not only realize the acidification of the bonding wire, but also realize the rinsing and drying of the bonding wire. The pickling unit has wide functionality. During the pickling operation, the plurality of pickling units can be coaxially assembled in sequence for use, that is, Figure 3As shown; it can be expanded that multiple continuous pickling units can be used to realize the single stages of over-acidification, rinsing, and drying, so as to achieve better stage effects and adapt to different pickling requirements of bonding wires. And there is no need to bend the bonding wires during the entire pickling process, reducing the probability of damage to the bonding wires. For example, the entire pickling operation is realized by five continuous pickling units, the first two pickling units realize the over-acidification stage of the bonding wires, the middle pickling unit realizes the rinsing stage of the bonding wires, and the last two pickling units realize the drying stage of the bonding wires.

[0033] like Figure 4 , Figure 5 As shown, the pickling unit includes a pickling box 10, and positioning mechanisms 15 are provided at the center of both ends of the pickling box 10. The inner wall of the pickling box 10 is rotatably connected with an arc-shaped hollow plate 20, and the top of the arc-shaped hollow plate 20 is provided with 23 connected to an external feeding device. The inner wall of the arc-shaped hollow plate 20 is interconnected with a plurality of staggered output pipes 21, and the plurality of output pipes 21 are symmetrically arranged in cross section.

[0034] 23 includes 231 interconnected with the top of the arc hollow plate 20, 231 is provided with 232, and the top of 231 is installed with 233. In the present invention, three 23 are provided, and the 233 at the top of the three 23 are respectively used to connect with external acid supply equipment, water supply equipment and hot air supply equipment. The corresponding external feeding equipment is connected according to the function of the acid supply unit, and 232 on the other two 23 are closed at the same time.

[0035] The working principle of the acid supply unit is as follows: under the guidance of the positioning mechanism 15, the bonding wire passes through the center of the cavity of the multiple coaxially arranged acid supply units, and then the 23 on the acid supply unit is connected to the corresponding external acid supply equipment, water supply equipment and hot air supply equipment, and then the pickling liquid / clean water / hot air enters the arc hollow plate 20 through the corresponding 231, and then is rinsed / blown to the bonding wire through the output pipe 21, thereby achieving the over-acidification / rinsing / drying of the bonding wire. In the present invention, the output pipes 21 in the inner cavity of the pickling box 10 are staggered and arranged symmetrically in cross section. Compared with the output pipes 21 arranged unidirectionally, the output pipes 21 arranged symmetrically in cross section can have a better rinsing / drying effect, and the symmetrically arranged output pipes 21 in the over-acidification and rinsing stages, the pickling liquid / clean water will be rinsed to the bonding wire in opposite directions, thereby causing the attachments / pickling liquid on the surface of the bonding wire to splash, which is easy to be attached to the bonding wire for a second time, resulting in incomplete over-acidification / rinsing; and the staggered and cross-sectionally symmetrically arranged output pipes 21 are unidirectionally rinsed, avoiding the above problems. At the same time, the staggered and cross-sectionally symmetrically arranged output pipes 21 also provide a basis for the subsequent liquid storage tank in the gravity deflection mechanism 30 to store liquid.

[0036] like Figure 6As shown, the pickling unit also includes a gravity deflection mechanism 30, which includes an arc-shaped extension plate 32 and a counterweight block 35 respectively arranged on the lower edges of both sides of the arc-shaped hollow plate 20, and the arc-shaped extension plate 32 is in contact with the inner wall of the pickling box 10, and the lower edge of the arc-shaped extension plate 32 is fixedly connected with an upper hook plate 33, and the two ends of the arc-shaped extension plate 32 and the upper hook plate 33 are jointly fixedly connected with a side sealing plate 36, and the arc-shaped extension plate 32, the upper hook plate 33, and the side sealing plate 36 are surrounded to form a liquid storage tank; a leakage hole 321 is opened at the lower edge of the arc-shaped extension plate 32; the bottom inner wall of the pickling box 10 is fixedly connected with a vertical plate 31, and a first magnetic block 311 is arranged on the side of the vertical plate 31 close to the upper hook plate 33, and a second magnetic plate 34 is fixedly connected to the top of the upper hook plate 33, and the second magnetic plate 34 corresponds to the first magnetic block 311 and repel each other magnetically.

[0037] When the pickling unit for over-acidification and flushing is being rinsed, since the output pipes 21 in the inner cavity of the pickling box 10 are staggered and arranged symmetrically in cross section, the pickling liquid / clean water sprayed on one side will flow along the inner wall of the arc-shaped hollow plate 20 to the liquid storage tank. This is the liquid storage stage, i.e. Figure 4 As shown, as more and more liquid is stored in the liquid storage tank, the arc hollow plate 20 and the output pipe 21 are driven to rotate along the inner wall of the pickling box 10 as a whole, and then rotate to the liquid lowering stage, which is Figure 5 As shown, in this stage, the lower leakage hole 321 and the discharge port 16 coincide with each other, and the liquid in the liquid storage tank flows outward from the leakage hole 321 and the discharge port 16, and the second magnetic plate 34 gradually approaches the first magnetic block 311. Due to the magnetic repulsion between the first magnetic block 311 and the second magnetic plate 34, the arc hollow plate 20, the output pipe 21, the liquid storage tank and other components gradually slow down their rotation as a whole; when the liquid in the liquid storage tank gradually decreases to a certain extent, under the combined action of the magnetic repulsion between the first magnetic block 311 and the second magnetic plate 34 and the gravity of the counterweight block 35, the arc hollow plate 20, the output pipe 21 and other components are driven to rotate in the opposite direction as a whole to the position shown in FIG. Figure 4 The liquid storage stage is shown, and the process reciprocates in this way. During the reciprocating rotation, the axial angle of the output tube 21 for flushing the bonding wire can be reciprocated to obtain a better acid perfusion and flushing effect on the bonding wire.

[0038] In the present invention, the pickling solution adopts tin-plating flux, and the ratio of tin-plating flux to industrial soft water is 1:3. The ratio concentration should be used according to the principle that the larger the wire diameter of the key joint wire, the higher the concentration.

[0039] A material discharge port 16 is provided at the bottom of the pickling box 10 , and a foot 11 is fixedly connected to the outer side of the bottom of the pickling box 10 , and the foot 11 makes the material discharge port 16 suspended in the air.

[0040] like Figure 1 , Figure 2As shown, the outer wall of the pickling box 10 is provided with a guide assembly, which includes a guide sleeve 131 and a guide rod 132. When a plurality of pickling units are coaxially assembled in sequence, the guide sleeve 131 and the guide rod 132 on the adjacent pickling unit are axially butted. In the present invention, the guide assembly adopts the guide sleeve 131 and the guide rod 132. In practical applications, the guide sleeve 131 and the guide rod 132 can be replaced by other guide components with the same function.

[0041] like Figure 7 As shown, the output pipe 21 includes a pipe body 211, and a pipe body cavity 2110 connected to the arc hollow plate 20 is arranged inside the pipe body 211; a nozzle 212 with a conical cross section is arranged at one end of the pipe body 211 away from the arc hollow plate 20, and a nozzle cavity 2120 is arranged inside the nozzle 212, and the tail end of the nozzle cavity 2120 is connected to the pipe body cavity 2110, and the tip of the nozzle cavity 2120 is directly facing the bonding line of the center of the inner cavity of the pickling box 10. In the present invention, by arranging the nozzle 212 and the nozzle cavity 2120, the water outlet port of the output pipe 21 can be pressurized, thereby improving the showering / blowing effect of the arc hollow plate 20.

[0042] like Figure 4 , Figure 5 As shown, a plurality of guide grooves 12 are provided on the top of the pickling box 10 , and the width of the guide grooves 12 is adapted to the outer diameter of 231 .

[0043] like Figure 2 , Figure 8 As shown, a center hole 14 for accommodating a positioning mechanism 15 is provided at the center of both ends of the pickling box 10. The positioning mechanism 15 includes a plurality of leg rods 151 fixedly connected to the inner wall of the center hole 14. A frame plate 152 is fixedly connected to one end of the plurality of leg rods 151 close to each other. A soft pad 153 is detachably installed at the center of the frame plate 152. A positioning through hole 154 matching the diameter of the bonding wire is provided at the center of the soft pad 153.

[0044] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them.

Claims

1. A single crystal copper bonding wire pickling device, characterized in that: The invention comprises a plurality of pickling units, which are coaxially assembled in sequence to form a pickling device, wherein the pickling units comprise a pickling box (10), positioning mechanisms (15) are arranged at the center of both ends of the pickling box (10), an arc-shaped hollow plate (20) is rotatably connected to the inner wall of the pickling box (10), a (23) connected to an external feeding device is arranged at the top of the arc-shaped hollow plate (20), and a plurality of staggered output pipes (21) are mutually connected to the inner wall of the arc-shaped hollow plate (20), and the plurality of output pipes (21) are arranged symmetrically in cross section; The pickling unit further comprises a gravity deflection mechanism (30), which drives the arc-shaped hollow plate (20) to periodically reciprocate in the inner wall of the pickling box (10) during the pickling stage, thereby adjusting the axial angle of the output pipe (21) for flushing the bonding line.

2. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: The pickling solution uses tin-plating flux, and the ratio of tin-plating flux to industrial soft water is 1:

3.

3. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: The bottom of the pickling box (10) is provided with a material discharge port (16), and the outer side of the bottom of the pickling box (10) is fixedly connected with a foot (11), and the foot (11) enables the material discharge port (16) to be in a suspended state.

4. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: The outer side wall of the pickling box (10) is provided with a guide assembly, the guide assembly comprising a guide sleeve (131) and a guide rod (132), and when a plurality of the pickling units are coaxially assembled in sequence, the guide sleeve (131) and the guide rod (132) on adjacent pickling units are axially butted.

5. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: The gravity deflection mechanism (30) comprises an arc-shaped extension plate (32) and a counterweight (35) respectively arranged at the lower edges of both sides of the arc-shaped hollow plate (20), and the arc-shaped extension plate (32) is in contact with the inner wall of the pickling box (10), the lower edge of the arc-shaped extension plate (32) is fixedly connected to an upper hook plate (33), and the two ends of the arc-shaped extension plate (32) and the upper hook plate (33) are commonly fixedly connected to a side sealing plate (36), and the arc-shaped extension plate (32), the upper hook plate (33) and the side sealing plate (36) are surrounded by a liquid storage tank; and a leakage hole (321) is opened at the lower edge of the arc-shaped extension plate (32).

6. The single crystal copper bonding wire pickling device according to claim 5, characterized in that: A vertical plate (31) is fixedly connected to the inner wall of the bottom of the pickling box (10); a first magnetic block (311) is arranged on one side of the vertical plate (31) close to the upper hook plate (33); a second magnetic plate (34) is fixedly connected to the top of the upper hook plate (33); the second magnetic plate (34) and the first magnetic block (311) correspond to each other and repel each other magnetically.

7. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: The output pipe (21) comprises a pipe body (211), the pipe body (211) being provided with a pipe body cavity (2110) in communication with the arc-shaped hollow plate (20); a pipe nozzle (212) having a conical cross section is provided at one end of the pipe body (211) away from the arc-shaped hollow plate (20), a pipe nozzle cavity (2120) is provided inside the pipe nozzle (212), the tail end of the pipe nozzle cavity (2120) is in communication with the pipe body cavity (2110), and the tip of the pipe nozzle cavity (2120) faces the bonding line at the center of the inner cavity of the pickling box (10).

8. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: The (23) includes a (231) interconnected with the top of the arc-shaped hollow plate (20), a (232) is arranged on the (231), and a (233) is installed on the top of the (231).

9. The single crystal copper bonding wire pickling device according to claim 8, characterized in that: The top of the pickling box (10) is provided with a plurality of guide grooves (12), and the width of the guide grooves (12) is adapted to the outer diameter of (231).

10. The single crystal copper bonding wire pickling device according to claim 1, characterized in that: A center hole (14) for accommodating a positioning mechanism (15) is provided at the center of both ends of the pickling box (10). The positioning mechanism (15) comprises a plurality of leg rods (151) fixedly connected to the inner wall of the center hole (14). One end of the plurality of leg rods (151) close to each other is fixedly connected to a frame plate (152). A soft pad (153) is detachably installed at the center of the frame plate (152). A positioning through hole (154) matching the diameter of the bonding wire is provided at the center of the soft pad (153).

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