Chip single-side corrosion device

Abstract

The utility model relates to a single-side corrosion device for a chip. The chip single-side corrosion device comprises an acid soaking tank body, a liquid supply pump and a bubble-free liquid storage barrel, the acid soaking tank body is provided with a liquid inlet / outlet and an overflow port, the liquid inlet / outlet is communicated with the liquid supply pump and the bubble-free liquid storage barrel, the overflow port is communicated with the bubble-free liquid storage barrel, the liquid supply pump is communicated with the bubble-free liquid storage barrel, and a plurality of acid soaking discs are arranged at the bottom of the acid soaking tank body. The acid soaking plates are used for placing chips to be corroded, liquid through holes are formed in the bottoms of the acid soaking plates, the liquid through holes are used for being communicated with the acid soaking tank body, positioning columns are arranged in the acid soaking plates in the circumferential direction, the positioning columns move in the height direction, and the positioning columns are used for supporting the chips. According to the utility model, the acid soaking tank body and the acid soaking disc with the positioning columns are arranged, so that the acid soaking time of the chip is controllable, the phenomenon of edge acid invasion of the chip is prevented, and the falling probability of a front surface structure layer or a passivation layer of the chip is better reduced.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor chip manufacturing technology, and more specifically, to a chip single-sided etching device. Background Technology

[0002] In the semiconductor device manufacturing process, single-sided etching is mainly used to remove the natural oxide layer on the back of the silicon wafer to expose a clean silicon surface, providing a substrate with high flatness and low interface states for subsequent metallization processes.

[0003] Current single-sided etching equipment for chips has difficulty controlling the contact time between the liquid surface and the chip when etching chips in batches. This leads to probabilistic acid immersion on the front side of the chip, which can cause the passivation layer or structural layer to peel off, directly affecting the yield of the chip. Utility Model Content

[0004] This invention provides a chip single-sided etching device that can overcome some or all of the defects of the prior art.

[0005] The chip single-sided etching device according to this utility model includes an acid soaking tank, a liquid supply pump, and a bubble-free storage tank. The acid soaking tank has an inlet / outlet and an overflow port. The inlet / outlet is connected to the liquid supply pump and the bubble-free storage tank, and the overflow port is connected to the bubble-free storage tank. The liquid supply pump is connected to the bubble-free storage tank. The bottom of the acid soaking tank is provided with multiple acid soaking trays for placing the chip to be etched. A liquid passage hole is formed at the bottom of the acid soaking tray for communicating with the acid soaking tank. A positioning post is provided circumferentially inside the acid soaking tray. The positioning post moves along the height direction and is used to support the chip.

[0006] In a preferred embodiment of this invention, a flow sensor is connected between the inlet / outlet and the feed pump.

[0007] In a preferred embodiment of this invention, the chip single-sided etching device further includes a PLC, which is electrically connected to a liquid supply pump and a flow sensor.

[0008] In a preferred embodiment of this invention, a modular clamp is provided in the acid soaking tray, which is used to abut and cooperate with the side wall of the chip.

[0009] In a preferred embodiment of this utility model, a liner is provided on the outer wall of the modular clamp, and the liner is used to abut against the inner wall of the acid soaking pan.

[0010] In a preferred embodiment of this invention, a laser level sensor is also provided at the acid soaking pan.

[0011] In a preferred embodiment of this invention, the chip single-sided etching device further includes a rinsing assembly, which includes a four-nozzle assembly and an acid recovery pipeline.

[0012] Beneficial effects:

[0013] The chip single-sided etching device provided in this embodiment of the utility model, by setting an acid soaking tank and an acid soaking plate with positioning columns, makes the acid soaking time of the chip controllable, prevents the chip from having edge acid penetration, and thus better reduces the probability of chip front structural layer or passivation layer peeling off.

[0014] Furthermore, the positioning column can be raised and lowered, and together with the laser level sensor, it can monitor the status of the chip in real time and adjust it in real time to ensure the levelness of the chip during the etching process, thereby improving the yield of the chip. Attached Figure Description

[0015] Figure 1 This is a schematic diagram showing the connection of components of the chip single-sided etching device in at least one embodiment of the present invention;

[0016] Figure 2 This is a schematic diagram of the internal structure of the chip single-sided etching device in at least one embodiment of the present invention;

[0017] Figure 3 This is a schematic diagram of an acid soaking tank in at least one embodiment of the present invention;

[0018] Figure 4 This is a schematic diagram of the four-nozzle structure in at least one embodiment of the present invention. Detailed Implementation

[0019] To clearly illustrate the technical solution of this utility model, the embodiments are described in full with reference to the accompanying drawings.

[0020] The accompanying drawings in this disclosure are not drawn to scale, and the number of acid soaking plates 4 and the number of positioning posts 5 are not limited to the quantities shown in the drawings. The specific dimensions and quantities of each structure can be determined according to actual needs.

[0021] Seen in Figure 1-4 This embodiment provides a chip single-sided etching device, which includes an acid soaking tank 1, a liquid supply pump 2, and a bubble-free storage tank 3. The acid soaking tank 1 has an inlet / outlet 11 and an overflow port 12. The inlet / outlet 11 is connected to the liquid supply pump 2 and the bubble-free storage tank 3, the overflow port 12 is connected to the bubble-free storage tank 3, and the liquid supply pump 2 is connected to the bubble-free storage tank 3.

[0022] Specifically, during use, the supply pump 2 is used to supply acid to the acid soaking tank 1. It can be understood that the supply pump 2 is a high-power centrifugal pump, which makes the supply of acid to the acid soaking tank 1 more stable. When the supply pump 2 is not working, the acid will quickly slide from the acid soaking tank 1 into the non-foaming storage tank 3 under the action of gravity. Therefore, the acid will not be in contact with the back of the chip for a long time, making the acid soaking of the chip controllable.

[0023] The bottom of the acid soaking tank 1 is provided with multiple acid soaking trays 4, which are used to place the chips to be etched. The bottom of the acid soaking tray 4 forms a liquid passage hole 41, which is used to communicate with the acid soaking tank 1. The acid soaking tray 4 is provided with a positioning post 5 along the circumferential direction. The positioning post 5 moves along the height direction and is used to support the chip.

[0024] Specifically, acid can enter and exit the acid soaking tray 4 through the liquid passage 41, and the positioning post 5 is used to support the chip. The positioning post 5 can move along the height direction, that is, the height of the chip in the acid soaking tray 4 is adjustable, so that the chip's posture can be adjusted in real time during use to prevent the structural layer or passivation layer on the front of the chip from falling off.

[0025] Furthermore, a flow sensor 6 is connected between the inlet / outlet 11 and the feed pump, thereby enabling real-time monitoring of the acid flow rate at the inlet / outlet 11.

[0026] In addition, the overflow port 12 is connected to the bubble-free storage tank 3. The acid is discharged into the bubble-free storage tank 3 by gravity at the overflow port 12, which can better reduce the liquid level fluctuation in the acid soaking tank 1, thereby reducing the probability that the front of the chip is in contact with the acid.

[0027] In this embodiment, the chip single-sided etching device also includes a PLC. The PLC is electrically connected to the liquid supply pump 2 and the flow sensor 6. The PLC performs logic control on the liquid supply pump 2 based on the data from the flow sensor 6, thereby ensuring that the time difference between the rise and fall of the liquid level in the acid soaking tank is ≤1 second.

[0028] In some embodiments, the acid soaking tray 4 is provided with a modular clamp, which is used to abut against the sidewall of the chip, thereby limiting the chip position.

[0029] The modular fixture has a liner on its outer wall, which abuts against the inner wall of the acid soaking tray 4. During use, the edge of the large-sized chip at the predetermined center position must be kept 18mm away from the edge of the acid soaking tray 4 to achieve a center-supported contact with the acid solution, utilizing the surface tension of the acid solution to etch the back of the chip from the center to the edge.

[0030] In some embodiments, the acid soaking tray 4 is also equipped with a laser level sensor, which can monitor the tilt of the silicon wafer in real time, so that the positioning post 5 can be raised and lowered in real time to ensure the levelness of the chip.

[0031] In some embodiments, the single-sided etching apparatus further includes a rinsing assembly comprising a quadruple nozzle 7 and an acid recovery pipeline. The quadruple nozzle 7 is used to clean residual acid on the back side of the silicon wafer after the etching operation is completed, and the cleaned liquid is recovered through the acid recovery pipeline.

[0032] The acid recovery pipeline is made of CPVC corrosion-resistant material to prevent residual acid leakage.

[0033] Understandably, during use, the etched silicon wafers can be transported to the rinsing assembly for rinsing by manual labor or robotic arms.

[0034] It is readily understood that those skilled in the art can combine, split, or reorganize the embodiments provided in this application to obtain other embodiments, all of which do not exceed the protection scope of this application.

Claims

1. A chip single-sided etching apparatus, characterized in that, The device includes an acid soaking tank, a liquid supply pump, and a bubble-free storage tank. The acid soaking tank has an inlet / outlet and an overflow port. The inlet / outlet is connected to the liquid supply pump and the bubble-free storage tank, and the overflow port is connected to the bubble-free storage tank. The liquid supply pump is connected to the bubble-free storage tank. The bottom of the acid soaking tank is provided with multiple acid soaking trays for placing the chips to be etched. The bottom of the acid soaking trays forms liquid passage holes for communicating with the acid soaking tank. Positioning posts are provided circumferentially inside the acid soaking trays. The positioning posts move along the height direction and are used to support the chips.

2. The chip single-sided etching apparatus according to claim 1, characterized in that, A flow sensor is connected between the inlet / outlet and the feed pump.

3. The chip single-sided etching apparatus according to claim 2, characterized in that, It also includes a PLC, which is electrically connected to the liquid supply pump and flow meter.

4. The chip single-sided etching apparatus according to claim 1, characterized in that, The acid soaking tray is equipped with modular fixtures, which are used to abut and engage with the sidewalls of the chip.

5. The chip single-sided etching apparatus according to claim 4, characterized in that, The modular fixture has a liner on its outer wall, which is used to abut against the inner wall of the acid soaking pan.

6. The chip single-sided etching apparatus according to claim 1, characterized in that, A laser level sensor is also installed at the acid soaking plate.

7. The chip single-sided etching apparatus according to claim 1, characterized in that, It also includes a flushing assembly, which consists of a four-spray nozzle and an acid recovery pipeline.

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