Precious metal recovery device for wafer wet etching wastewater

Abstract

The utility model discloses a precious metal recovery device for wafer wet etching wastewater, which comprises an electroplating deposition tank comprising an anode and a cathode, the cathode is connected with a stainless steel plate for depositing metal ions, the anode is connected with a wafer to be etched and dissolved, and a liquid supplementing pipe is communicated to the electroplating deposition tank; the conveying line is used for conveying the metal material deposited on the stainless steel plate, and a heating device used for drying the metal material is arranged on the conveying line; the electrolytic refining tank is arranged at one end of the conveying line; the rinsing tank is arranged on one side of the electrolytic refining tank; and the high-temperature refining furnace is arranged on one side of the rinsing bath. Compared with the prior art, the utility model solves the problem of high treatment cost of wafer electroplating wastewater and wet etching wastewater.

Description

A device for recovering precious metals from wafer wet etching wastewater Technical Field

[0001] This utility model relates to the field of wafer wet etching technology, and in particular to a precious metal recovery device for wafer wet etching wastewater. Background Technology

[0002] Etching technology is a technique used in semiconductor manufacturing processes to selectively etch or strip the surface of a semiconductor substrate or a thin film covering its surface according to mask patterns or design requirements. Etching techniques can be divided into wet etching and dry etching. Wet etching involves immersing the etching material in an etching solution for etching.

[0003] In existing technologies, precious metals are present in the wastewater generated during the UBM (Under Bump Metal) fabrication process in wafer electroplating and in the wastewater generated during wafer wet etching. Traditional reverse electroplating equipment removes the metal layer by reversing the anode and cathode, but the wastewater still requires expensive treatment. In addition, the direct discharge of precious metal waste liquid leads to both material waste and environmental costs. Summary of the Invention

[0004] The purpose of this invention is to provide a precious metal recovery device for wafer wet etching wastewater, so as to solve the problem of high treatment costs for wafer electroplating wastewater and wet etching wastewater.

[0005] To achieve the above objectives, this utility model adopts the following technical solution: a precious metal recovery device for wafer wet etching wastewater, comprising:

[0006] An electroplating deposition tank includes an anode and a cathode. The cathode is connected to a stainless steel plate for depositing metal ions, and the anode is connected to a wafer to be etched and dissolved. A replenishment pipe is connected to the electroplating deposition tank.

[0007] A conveyor line for conveying metal material deposited on stainless steel plates, and a heating device for drying the metal material is installed on the conveyor line.

[0008] An electrolytic refining cell is located at one end of the conveyor line;

[0009] A water washing tank is located on one side of the electrolytic refining tank;

[0010] The high-temperature refining furnace is located on one side of the water washing tank.

[0011] As a further description of the above technical solution:

[0012] The heating device includes several hot blowers arranged along the conveying direction of the conveyor line.

[0013] As a further description of the above technical solution:

[0014] Several temperature sensors are arranged at equal intervals along the conveying direction of the conveyor line.

[0015] As a further description of the above technical solution:

[0016] A filter basket is installed inside the washing tank.

[0017] As a further description of the above technical solution:

[0018] The filter basket is provided with a hanging part, which is hung on the side wall of the washing tank.

[0019] As a further description of the above technical solution:

[0020] The attachment part is provided with a connecting ear, and the electric hoist is positioned above the connecting ear.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0022] In this invention, wafer electroplating wastewater and wet etching wastewater are fed into an electroplating deposition tank via a replenishment pipe. When recovering gold, metal ions in the wastewater are deposited onto a stainless steel plate through a cathode. The deposited metal material on the stainless steel plate is placed on a conveyor line for transport, and during the transport process, it is baked and dried online by a heating device. The dried metal material is sent to an electrolytic refining tank for further electrolytic refining to remove metal impurities. The refined gold deposited at the negative electrode of the electrolytic refining tank is removed and sent to a water washing tank for cleaning. The cleaned refined gold is sent to a high-temperature refining furnace for further melting and impurity removal, thereby realizing the recovery of precious metals, reducing material waste, lowering the concentration of metal ions in the wastewater, reducing the amount of subsequent chemical neutralizing agents used and the wastewater treatment load, and thus reducing the overall environmental protection cost. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 is a schematic diagram of a precious metal recovery device for wafer wet etching wastewater.

[0025] Figure 2 is a schematic diagram of the water washing tank in a precious metal recovery device for wafer wet etching wastewater.

[0026] Legend:

[0027] 1. Electroplating deposition tank; 11. Anode; 12. Cathode; 13. Drain pipe; 2. Conveyor line; 21. Heating device; 211. Hot blower; 22. Temperature sensor; 3. Electrolytic refining tank; 4. Washing tank; 41. Filter basket; 411. Hanging part; 412. Connecting ear; 5. High-temperature refining furnace; 6. Electric hoist; 9. Liquid replenishment pipe. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0029] Example 1

[0030] Please refer to Figures 1-2. This utility model provides a technical solution: a precious metal recovery device for wafer wet etching wastewater, comprising:

[0031] Electroplating deposition tank 1 includes an anode 11 and a cathode 12. The cathode 12 is connected to a stainless steel plate for depositing metal ions, and the anode 11 is connected to a wafer to be etched and dissolved. The replenishment pipe 9 is connected to the electroplating deposition tank 1.

[0032] Conveyor line 2 is used to convey metal material deposited on stainless steel plates and scraped off. A heating device 21 for drying the metal material is provided on conveyor line 2.

[0033] An electrolytic refining cell 3 is located at one end of the conveyor line 2;

[0034] A water washing tank 4 is located on one side of an electrolytic refining tank 3;

[0035] The high-temperature refining furnace 5 is located on one side of the water washing tank 4.

[0036] A filter basket 41 is installed inside the washing tank 4. The filter basket 41 is immersed in the cleaning solution in the washing tank 4. After the refined metal material is cleaned, the filter basket 41 is lifted to collect it.

[0037] The electroplating deposition tank 1 is equipped with a drain pipe 13. This allows for the timely discharge of treated wastewater, facilitating wastewater recycling.

[0038] Working Principle: Wastewater from wafer electroplating and wet etching is introduced into electroplating deposition tank 1 via replenishment pipe 9. During gold recovery, metal ions in the wastewater are deposited onto a stainless steel plate through cathode 12. The deposited metal material on the stainless steel plate is placed on conveyor line 2 for transport, and during transport, it is baked and dried online by heating device 21. The dried metal material is sent to electrolytic refining tank 3 for further electrolytic refining to remove metal impurities. The refined gold deposited at the negative electrode of electrolytic refining tank 3 is removed and sent to water washing tank 4 for cleaning. The cleaned refined gold is sent to high-temperature refining furnace 5 for further melting and impurity removal, thus realizing the recovery of precious metals, reducing material waste, lowering the concentration of metal ions in the wastewater, reducing the amount of subsequent chemical neutralizing agents used and the wastewater treatment load, thereby reducing the overall environmental protection cost. The higher the concentration of metal ions in the wastewater, the more precious metals are recovered, and the lower the wastewater treatment cost.

[0039] Example 2

[0040] Based on the above embodiments, this embodiment further improves upon the following technical solution: the heating device 21 includes several hot blowers 211 arranged along the conveying direction of the conveyor line 2 to realize online baking and drying of metal materials.

[0041] In addition, several temperature sensors 22 are arranged at equal intervals along the conveying direction of the conveyor line 2. The temperature sensors 22 monitor the baking temperature of the recycled metal material on the conveyor line 2 to ensure the drying effect.

[0042] Example 3

[0043] This embodiment further improves upon the above embodiment by providing the following technical solution: The filter basket 41 is provided with a hanging part 411, which is hung on the side wall of the washing tank 4. The filter basket 41 is positioned on the washing tank 4 via the hanging part 411, controlling its placement and facilitating lifting.

[0044] In addition, a connecting ear 412 is provided on the hook part 411, and the electric hoist 6 is positioned above the connecting ear 412. The electric hoist 6 can hook the connecting ear 412 to drive the filter basket 41 upward, making it easier to lift the filter basket 41.

[0045] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A device for recovering precious metals from wafer wet etching wastewater, characterized in that, include: An electroplating deposition tank includes an anode and a cathode, the cathode being connected to a stainless steel plate for depositing metal ions, the anode being connected to a wafer to be etched and dissolved, and a replenishment pipe connected to the electroplating deposition tank; a conveyor line for conveying the metal material deposited on the stainless steel plate, and a heating device for drying the metal material is provided on the conveyor line. An electrolytic refining cell is disposed at one end of the conveyor line; A water washing tank is located on one side of the electrolytic refining tank; A high-temperature refining furnace is located on one side of the water washing tank.

2. The precious metal recovery device for wafer wet etching wastewater according to claim 1, characterized in that, The heating device includes a plurality of hot blowers arranged along the conveying direction of the conveyor line.

3. The precious metal recovery device for wafer wet etching wastewater according to claim 1, characterized in that, Several temperature sensors are arranged at equal intervals along the conveying direction of the conveyor line.

4. The precious metal recovery device for wafer wet etching wastewater according to claim 1, characterized in that, A filter basket is installed inside the washing tank.

5. A precious metal recovery device for wafer wet etching wastewater according to claim 4, characterized in that, The filter basket is provided with a hanging part, which is hung on the side wall of the washing tank.

6. A precious metal recovery device for wafer wet etching wastewater according to claim 5, characterized in that, The mounting part is provided with a connecting ear, and the electric hoist is positioned above the connecting ear.

7. A precious metal recovery device for wafer wet etching wastewater according to claim 1, characterized in that, The electroplating deposition tank is equipped with a drain pipe.

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