Technology for manufacturing selective emitter junction solar cell by printed phosphorous source one-step diffusion method

Abstract

The invention relates to technology for manufacturing a selective emitter junction solar cell by a printed phosphorous source one-step diffusion method. The method comprises the following steps of: cleaning and texturing a silicon wafer, performing screen printing of phosphorous-containing nano Si slurry, drying at the temperature of between 200 and 350 DEG C for about 20 minutes, and removing the solvent to obtain a phosphorous-containing oxidation layer with the thickness of 30 to 100nm; implementing BOE and RCA cleaning to remove 70 percent of surface phosphorous slurry before diffusion; putting the silicon wafer into a diffusion furnace, adding a POCL3 air source, heating to between 800 and 1,000 DEG C, forming re-diffusion at a grid line of the phosphorous-containing nano slurry on the silicon wafer to form a higher surface concentration-heavily doped region, and forming a shallow diffusion region in other areas. By adopting the screen printing of the phosphorous-containing nano slurry, the phosphorous-containing nano slurry is heated at high temperature for diffusion, forms the heavily doped region at a contact position with the grid line and forms a lightly doped region in other areas. The technology has the efficiency of over 18.5 percent on the premise of better controlling the diffusion uniformity.

Description

technical field [0001] The invention relates to a method for realizing a selective emission junction solar cell technology and the preparation of the cell, in particular to a process for manufacturing a selective emission crystalline silicon solar cell by a single-step diffusion method of a printed phosphorus source. Background technique [0002] Selective emitter junction solar cells, that is, heavy doping is carried out at the electrode contact point, and light doping is carried out at the position between the electrodes. Such a structure can reduce the recombination of the diffusion layer and improve the short-wave response, and at the same time reduce the contact resistance between the front metal electrode and silicon, so that the short-circuit current, open-circuit voltage and fill factor are all improved, thereby improving the conversion efficiency. Due to the unique cell structure characteristics of selective emitter solar cells, it has become a research hotspot at h...

AI Technical Summary

Problems solved by technology

Photolithography mask technology and anti-corrosion technology, complex processes affect process efficiency and increase production costs, which cannot be accepted by solar cell companies that emphasize simplicity and low cost, while other methods such as secondary diffusion and other The mask method also greatly increases the complexity of the process. The increase in cost and the decrease in efficiency are not enough to make up for the increase in battery efficiency, which limits its industrial application. More and more research is oriented towards simplified processes and implementation methods.