CN111354623A - A kind of cold water slow pulling and cleaning process of silicon wafer - Google Patents

Abstract

A process for slowly pulling and cleaning silicon wafers in cold water, comprising the following steps: placing a flower basket containing silicon wafers on wet-processing equipment; starting the wet-processing equipment to perform preliminary cleaning on the silicon wafers; and running the silicon wafers after preliminary cleaning to a slow In the lifting tank, the slow lifting tank contains room temperature water, and the silicon wafers are cleaned with the normal temperature water; the flower basket containing the silicon wafers after the fast cleaning is lifted from the slow lifting tank to the highest point; Dry in a drying tank. The invention has the advantages that: the slow pulling tank can quickly discharge and clean the silicon wafer, which can reduce impurities on the surface of the silicon wafer, improve the quality and yield of the silicon wafer, and use cold water to clean the silicon wafer, which can reduce the consumption of heat energy. Reduce production costs.

Description

A kind of cold water slow pulling and cleaning process of silicon wafer

technical field

The invention relates to the technical field of preparation of solar cell sheets, in particular to a process for slowly pulling and cleaning silicon wafers with cold water.

Background technique

In the preparation process of the solar cell, the silicon wafer needs to be washed with water to remove impurities on the surface of the silicon wafer, and then dried for the next process. In the slow pulling tank of hot water, the robot is used for slow pulling to remove the moisture on the surface of the silicon wafer, which saves the subsequent drying time, but simple water washing cannot completely remove the impurities in the silicon wafer, resulting in a low utilization rate of the silicon wafer. , therefore, the present invention provides a process for reducing impurities on the surface of silicon wafers by using cold water slow pulling.

SUMMARY OF THE INVENTION

The purpose of the present invention is to use a cold water slow pulling device to reduce impurities on the surface of the silicon wafer, so the present invention provides a cold water slow pulling and cleaning process for the silicon wafer.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: a process for cleaning silicon wafers by slow pulling in cold water, which is characterized in that: the following steps are included in sequence:

(1) Place the flower basket containing the silicon wafers at the loading end of the wet process equipment;

(2) Start the wet process equipment to perform preliminary cleaning on the silicon wafer;

(3) Place the preliminarily cleaned silicon wafer in a slow-lifting tank, which contains normal temperature water, and use normal-temperature water to quickly clean the silicon wafer;

(4) Lift the flower basket containing the silicon wafers after quick row cleaning to the highest point from the slow pulling groove;

(5) place the flower basket in the drying tank for drying;

Preferably, the quick-discharge cleaning steps are:

a. The silicon wafer is cleaned by the method of top water injection + fast drainage, and the cleaning time is 40 seconds;

b. Use the method of upper water injection + lower water injection to clean the silicon wafer, and the cleaning time is 90 seconds;

c. The silicon wafer is cleaned by overflow cleaning, and the cleaning time is 60 seconds;

Repeat steps a to c 3 times.

Preferably, the temperature of the normal temperature water is 18°C-23°C.

The advantages and positive effects of the invention are as follows: the slow lifting tank adopts the methods of upper water injection + fast drainage, upper water injection + lower water injection, and overflow cleaning to clean the silicon wafer, which can reduce impurities on the surface of the silicon wafer and improve the performance of the silicon wafer. In terms of quality and yield, due to the reduction of impurities on the surface of the silicon wafer, the silicon wafer coming out of the slow pulling tank contains less moisture, which is convenient for the subsequent drying steps. Reduce thermal energy consumption, reduce production costs and improve economic benefits.

Detailed ways

Embodiments of the present invention are further described below:

A process for slowly pulling and cleaning silicon wafers in cold water, comprising the following steps:

(1) Put the silicon wafers to be cleaned in the flower basket, place a pressure bar above the flower basket to facilitate the separation of the silicon wafers, and then place the flower basket at the loading end of the wet process equipment;

(2) Start the wet process equipment to perform preliminary cleaning on the silicon wafer;

(3) The preliminarily cleaned silicon wafers are run into the slow pulling tank, which contains room temperature water, and the wafers are cleaned quickly with normal temperature water;

(4) Use the robot to gradually lift the flower basket from the bottom of the slow-lifting groove to the highest point;

(5) the flower basket is placed in the drying tank to be dried, and the drying time is 3 to 5 minutes, and the drying temperature is 80 to 90 ° C, and is finally cooled for 2 to 3 minutes;

The steps of quick discharge cleaning are:

(1) The silicon wafer is cleaned by the method of upper water injection + fast drainage. The cleaning time is 40 seconds. That is, a water injection device is installed above the slow pulling tank to inject water into the slow pulling tank. At the same time, the slow pulling tank is also provided with There is a drain pipe that can quickly drain water to the outside, so that the impurities cleaned on the surface of the silicon wafer can be quickly discharged from the slow-lifting tank with the drainage, and the water injection device can replenish the water lost in the slow-lifting tank to ensure that the silicon wafer can be completely immersed in the tank. water. Preferably, the water injection device is a spray device.

(2) The silicon wafer is cleaned by the method of upper water injection + lower water injection. The cleaning time is 90 seconds, that is, there are water injection devices above and below the slow pulling tank, which can simultaneously inject water into the slow pulling tank and increase the injection rate. The amount of water to ensure that the water level in the slow pulling tank can immerse the silicon wafer.

(3) The silicon wafer is cleaned by means of overflow cleaning, and the cleaning time is 60 seconds, that is, water injection is provided under the slow-lifting tank, so that the water in the slow-lifting tank overflows.

Repeat the above steps (1)-(3), after repeating 3 times, use the robot to pull up the flower basket containing the silicon wafer, and pull it to the highest point after 3 to 4 minutes, the pulling speed is 10m/s, and the slow lifting The pulling method can dehydrate the surface of the silicon wafer, and the fast cleaning of the slow pulling tank can reduce the impurities on the surface of the silicon wafer, which can improve the quality of the silicon wafer on the one hand, and reduce the moisture content carried by the impurities on the other hand. In the subsequent drying steps, the drying time can be shortened and the work efficiency can be accelerated.

Preferably, normal temperature water is placed in the slow pulling tank to clean the silicon wafer. Compared with the method of hot water cleaning, normal temperature water cleaning can reduce the consumption of heat energy and the production cost.

Preferably, the temperature of the normal temperature water is 18°C-23°C.

The advantages and positive effects of the invention are as follows: the slow lifting tank adopts the methods of upper water injection + fast drainage, upper water injection + lower water injection, and overflow cleaning to clean the silicon wafer, which can reduce impurities on the surface of the silicon wafer and improve the performance of the silicon wafer. In terms of quality and yield, due to the reduction of impurities on the surface of the silicon wafer, the silicon wafer coming out of the slow pulling tank contains less moisture, which is convenient for the subsequent drying steps. Reduce thermal energy consumption, reduce production costs and improve economic benefits.

An embodiment of the present invention has been described in detail above, but the content is only a preferred embodiment of the present invention, and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the application of the present invention should still belong to the scope of the patent of the present invention.

Claims (4)

1. A process for cleaning a silicon wafer by slow cold water pulling is characterized by comprising the following steps: the method sequentially comprises the following steps:

(1) placing the flower basket containing the silicon wafers at a feeding end of wet equipment;

(2) starting wet equipment, and preliminarily cleaning the silicon wafer;

(3) placing the preliminarily cleaned silicon wafer into a slow pulling groove, wherein the slow pulling groove contains normal-temperature water, and quickly discharging and cleaning the silicon wafer by using the normal-temperature water;

(3) lifting the flower basket containing the silicon chips after the quick-drain cleaning from the slow lifting groove to the highest point;

(4) and (5) drying the flower basket in a drying groove.

2. The process for cleaning the silicon wafer by slow cold water pulling as claimed in claim 1, wherein the process comprises the following steps: the quick-discharge cleaning step comprises:

(1) cleaning the silicon wafer by adopting a mode of upper water injection and quick water drainage, wherein the cleaning time is 40 seconds;

(2) cleaning the silicon wafer by adopting a mode of upper water injection and lower water injection, wherein the cleaning time is 90 seconds;

(3) and cleaning the silicon wafer in an overflow cleaning mode for 60 seconds.

3. The process for cleaning the silicon wafer by slow cold water pulling as claimed in claim 2, wherein: repeating the steps (1) to (3) for 3 times.

4. The process for cleaning the silicon wafer by slow cold water pulling as claimed in claim 1, wherein the process comprises the following steps: the temperature of the normal temperature water is 18-23 ℃.