Cooling device for mixed acid used in diode manufacturing

Abstract

The utility model discloses a mixed acid cooling device for diode manufacturing relates to diode manufacturing equipment field, including acid pump, acid pool, cooling water tank, cooling coil, infusion tube, back liquid pipe, filter, baffle and liquid inlet pipe, the baffle in acid pool divides it into first acid groove and second acid groove, and cooling coil is placed in cooling water tank, and acid pump drives acid liquid to form circulation through infusion tube, cooling coil, back liquid pipe, and cooling coil, infusion tube, back liquid pipe and liquid inlet pipe all are tetrafluoroethylene tube, and the filter is equipped on infusion tube. The utility model discloses through circulating cooling, realizes that mixed acid temperature is stable at 11 DEG C plus or minus 3 DEG C, and tetrafluoroethylene tube avoids that acid liquid enters water and is corroded, and the baffle cooperates filter and realizes impurity separation, solves the poor cooling effect of existing device, the problem of easy failure, reduces diode product failure rate, and simple structure, strong practicality.

Description

Technical Field

[0001] This utility model relates to the field of diode manufacturing equipment technology, specifically to a device for cooling mixed acid during diode manufacturing. Background Technology

[0002] In the diode manufacturing process, the chip needs to undergo acid etching with mixed acid. This process has strict requirements on the temperature of the mixed acid, which needs to be controlled within the range of 11℃±3℃. The stability of the mixed acid temperature directly determines the quality of the diode product.

[0003] Existing mixed acid cooling devices have two major problems in practical use: First, the cooling effect is poor, and the temperature of the mixed acid tends to rise gradually, making it impossible to maintain the temperature range required by the process; Second, the structural design has defects, which can easily lead to acid water ingress failure, which will not only change the concentration of the mixed acid and damage its performance, but also cause abnormalities in the subsequent diode manufacturing process, significantly increasing the product defect rate and making it difficult to meet the process standards and quality requirements of diode manufacturing.

[0004] Therefore, there is an urgent need for a mixed acid cooling device that can stably control the temperature of the mixed acid, prevent water from entering the acid solution, and has the function of separating impurities, so as to overcome the shortcomings of the existing technology. Utility Model Content

[0005] To address the problems of poor cooling effect, easy acid water ingress, and high product defect rate caused by the lack of impurity separation function in existing mixed acid cooling devices, this utility model provides a mixed acid cooling device for diode manufacturing, which realizes the functions of rapid cooling of mixed acid, stable temperature control, prevention of acid water ingress, and impurity separation.

[0006] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A mixed acid cooling device for diode manufacturing includes an acid pump (1), an acid pool (2), a cooling water tank (3), a cooling coil (4), a delivery pipe (5), a return pipe (6), a filter (7), a partition (8), and an inlet pipe (9). The acid tank (2) is fixedly equipped with a partition (8), which divides the acid tank (2) into a first acid tank (21) and a second acid tank (22) that are independent of each other and connected at the top. The height of the partition (8) is lower than the height of the inner wall of the acid tank (2), so that the acid in the first acid tank (21) can overflow to the second acid tank (22), and the dense impurities are deposited at the bottom of the first acid tank (21). The inner wall of the acid tank (2) is lined with a layer of PTFE material, and the outer side of the partition (8) is also covered with a layer of PTFE material and forms an integral part with the PTFE material layer on the inner wall of the acid tank (2). The cooling water tank (3) has a hollow cavity structure, and a cooling coil (4) is fixedly installed inside it. The inlet end of the cooling coil (4) is connected to the outlet end of the acid pump (1) through the liquid delivery pipe (5). The inlet end of the acid pump (1) is connected to the bottom of the second acid tank (22) of the acid pool (2) through the liquid inlet pipe (9). The outlet end of the cooling coil (4) is connected to the top of the first acid tank (21) of the acid pool (2) through the liquid return pipe (6). A filter (7) is installed in series on the inlet pipe (9) to filter suspended impurities in the acid solution; The cooling coil (4), the inlet pipe (5), the return pipe (6), and the inlet pipe (9) are all made of PTFE tubing.

[0007] Compared with the prior art, the beneficial effects of this utility model are as follows: High cooling efficiency and stable temperature: The acid liquid is driven by the acid pump to form a closed loop circulation between "acid pool - cooling coil - acid pool". The cooling coil is placed in the cooling water tank, which can continuously and uniformly cool the acid liquid and ensure that the temperature of the mixed acid is stable within the process range of 11℃±3℃, thus solving the problem of poor cooling effect of the existing equipment. Preventing acid ingress and corrosion: Cooling coils, inlet pipes, return pipes, and inlet pipes are all made of acid- and corrosion-resistant PTFE tubing to prevent acid ingress due to pipeline corrosion and leakage, thus ensuring the stability of mixed acid concentration and performance. Impurity separation function: The baffle in the acid tank divides the acid return path into "first acid tank (impurity deposition) - second acid tank (overflow of pure acid)", which, together with the filter on the infusion pipe, achieves double impurity filtration, avoids impurities clogging the pipeline or affecting the acid etching process, and reduces the product defect rate. Attached Figure Description

[0008] Figure 1 is a schematic diagram of the mixed acid cooling device for diode manufacturing according to this utility model.

[0009] In the diagram: 1 - acid pump, 2 - acid tank, 21 - first acid tank, 22 - second acid tank, 3 - cooling water tank, 4 - cooling coil, 5 - infusion pipe, 6 - return pipe, 7 - filter, 8 - baffle plate, 9 - inlet pipe. Detailed Implementation

[0010] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings.

[0011] As shown in Figure 1, a mixed acid cooling device for diode manufacturing includes an acid pump (1), an acid pool (2), a cooling water tank (3), a cooling coil (4), a delivery pipe (5), a return pipe (6), a filter (7), a partition (8), and an inlet pipe (9).

[0012] Component assembly details Acid tank and baffle: The acid tank (2) is made of ordinary steel plate, and the baffle (8) is welded and fixed inside. The height of the baffle (8) is 5-8cm lower than the inner wall of the acid tank (2) to form an overflow channel; the volume of the first acid tank (21) is 1 / 3 of the total volume of the acid tank (2) to facilitate the deposition of impurities; the volume of the second acid tank (22) is 2 / 3 of the total volume of the acid tank (2) to store pure mixed acid to be cooled; the inner wall of the acid tank (2) is lined with a layer of PTFE material, and the outer side of the baffle (8) is also covered with a layer of PTFE material and forms an integral part with the PTFE material layer on the inner wall of the acid tank (2). The PTFE material layer is designed to have good anti-corrosion effect and reduce costs; Acid pump: Fluoroplastic centrifugal pump with a flow rate of 20-25m³ / h; Cooling system: Industrial cooling water is injected into the cooling water tank (3). The cooling coil (4) adopts a serpentine PTFE tube structure and is coiled and installed inside the cooling water tank (3) to ensure that the cooling coil (4) is completely submerged in the cooling water and improve the heat exchange efficiency. Piping connection: One end of the infusion pipe (5) is connected to the outlet end of the acid pump (1) through a flange, and the other end is inserted into the cooling water tank (3) and welded to the inlet end of the cooling coil (4); the inlet end of the acid pump (1) is connected to the bottom of the second acid tank (22) of the acid pool (2) through the inlet pipe (9); one end of the return pipe (6) is welded to the outlet end of the cooling coil (4), and the other end extends into the first acid tank (21) with the port 10-15cm away from the bottom of the tank to avoid disturbing the deposited impurities; the filter (7) uses a PTFE filter element, which is connected in series to the end of the inlet pipe (9) near the acid pump (1), and the inner side of the filter (7) is also lined with a layer of PTFE material for corrosion protection.

[0013] Work process: External mixed acid is injected into the second acid tank (22) of the acid pool (2) through the replenishment pipe. When the mixed acid level reaches the set height, the acid pump (1) is started. Acid pump (1) extracts mixed acid from the second acid tank (22) through inlet pipe (9), and delivers it to filter (7) through delivery pipe (5). After filtering out suspended impurities, it enters the cooling coil (4) in cooling water tank (3). When the mixed acid flows in the cooling coil (4), it exchanges heat with the cooling water in the cooling water tank (3), and the temperature drops to 11℃±3℃. After cooling, the mixed acid flows into the first acid tank (21) through the return pipe (6). High-density impurities in the mixed acid (such as metal scraps and acid etching residues) are deposited at the bottom of the first acid tank (21). The pure mixed acid in the first acid tank (21) flows into the second acid tank (22) through the top overflow channel and re-enters the circulating cooling process to achieve continuous cooling and purification of the mixed acid.

[0014] In this embodiment, the above-described structure and workflow can stably control the mixed acid temperature, avoid water ingress and impurity interference, and fully meet the mixed acid process requirements for diode manufacturing.

Claims

1. A mixed acid cooling apparatus for diode manufacturing, characterized in that, The system includes an acid pump (1), an acid tank (2), a cooling water tank (3), a cooling coil (4), a delivery pipe (5), a return pipe (6), a filter (7), a partition (8), and an inlet pipe (9). The acid tank (2) is internally fitted with a partition (8), which divides the acid tank (2) into a first acid tank (21) and a second acid tank (22). The height of the partition (8) is lower than the height of the inner wall of the acid tank (2). The cooling water tank (3) is internally fitted with a cooling coil (4), the inlet end of which is connected to the outlet end of the acid pump (1) via the delivery pipe (5). The inlet end of the acid pump (1) is connected to the second acid tank (22) of the acid pool (2) through the inlet pipe (9); the outlet end of the cooling coil (4) is connected to the first acid tank (21) of the acid pool (2) through the return pipe (6); a filter (7) is installed in series on the inlet pipe (9); the cooling coil (4), the delivery pipe (5), the return pipe (6) and the inlet pipe (9) are all made of PTFE tubing; the inner wall of the acid pool (2) is lined with a layer of PTFE material, and the outer side of the partition (8) is also covered with a layer of PTFE material and forms an integral part with the PTFE material layer on the inner wall of the acid pool (2).

2. The mixed acid cooling apparatus for diode manufacturing according to claim 1, characterized in that, The volume of the first acid tank (21) is 1 / 3 of the total volume of the acid pool (2), and the volume of the second acid tank (22) is 2 / 3 of the total volume of the acid pool (2).

3. The mixed acid cooling apparatus for diode manufacturing according to claim 1, characterized in that, The cooling coil (4) has a serpentine structure and is completely submerged in the cooling water in the cooling water tank (3).

4. The mixed acid cooling apparatus for diode manufacturing according to claim 1, characterized in that, The port of the return pipe (6) extending into the first acid tank (21) is 10-15cm away from the bottom of the first acid tank (21).

5. The mixed acid cooling apparatus for diode manufacturing according to claim 1, characterized in that, The filter (7) uses a PTFE filter element and is located close to the acid pump (1); the inner side of the housing of the filter (7) is also lined with a PTFE material layer.

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