Method for cleaning and saturating quartz boat for diffusion of crystalline silicon solar cell

Abstract

The invention discloses a method for cleaning and saturating a quartz boat for diffusion of a crystalline silicon solar cell. The method comprises the following steps: 1) completely soaking the quartz boat in a mixed acid solution of HF and HCL; 2) soaking and cleaning the quartz boat in pure water; 3) cleaning with a water gun or spraying after the pure water is completely discharged; 4) blow-drying the quartz boat by using a nitrogen gun; 5) putting the quartz boat into a diffusion furnace tube, and introducing nitrogen for purging when the quartz boat enters the diffusion furnace tube; 6) vacuumizing a diffusion furnace tube, introducing nitrogen and oxygen into the diffusion furnace tube, and increasing the temperature; 7) introducing phosphorus oxychloride and oxygen, 8) introducing nitrogen and oxygen and cooling, and 9) charging nitrogen into the furnace tube to return to normal pressure and taking out of the quartz boat. The total treatment time can be shortened, the gas consumption is reduced, corrosion to a quartz boat and the furnace tube is reduced, the yield of produced battery pieces is improved, the productivity is improved, and the production and operation cost is reduced.

Description

technical field [0001] The invention relates to the field of photovoltaics, in particular to a method for cleaning and saturating a quartz boat used for diffusion of crystalline silicon solar cells. Background technique [0002] The diffusion process is the process of preparing PN junctions in the manufacturing process of crystalline silicon solar cells. The quartz boat is used to repeatedly load silicon wafers and place them in the diffusion quartz furnace tube to complete the diffusion process. During the diffusion process, phosphorus atoms are deposited on the surface of the silicon wafer through the reaction of phosphorus oxychloride gas and oxygen at high temperature. During this process, an intermediate product, phosphorus pentoxide, is formed and attached to the quartz boat in a small amount. The contact between phosphorus and water vapor in the air will form metaphosphoric acid, and the accumulated metaphosphoric acid will pollute the silicon wafer, and because the s...

AI Technical Summary

Problems solved by technology

[0004] The normal diffusion production process takes 105 minutes. The total processing time of the existing quartz boat cleaning and saturation process is about 400 minutes, which seriously affects the turnover and use of the quartz boat and affects the production capacity. Thin, reducing the service life of the quartz boat, the ultra-high temperature saturation process is easy to accelerate the aging of equipment components such as the furnace tube sealing ring, and the reaction of phosphorus oxychloride for a long time is easy to accumulate too much metaphosphoric acid in the furnace tube tail gas treatment device, resulting in pipeline blockage And accelerate pipeline corrosion