Method for preparing monocrystalline silicon surface-passivated cell

Abstract

The invention discloses a method for preparing a monocrystalline silicon surface-passivated cell. The method specifically comprises the steps of: (1) by adopting an improved diffusion technology, diffusion is carried out on a monocrystalline silicon sheet after cleaning and texturing in a tube-type diffusion furnace; (2) after the monocrystalline silicon sheet is subjected to texturing and diffusion, PSG after the diffusion is removed by HF in a secondary cleaning tank; (3) in the diffusion furnace, a dry-oxygen oxidation method is firstly adopted so as to enable a layer of thin silicon dioxide film to grow on the surface of the silicon sheet, then wet-oxygen oxidation is carried out in a wet-oxygen atmosphere, suitable source introduction deposition is simultaneously carried out, and finally the dry-oxygen oxidation is carried out again; (4) etching is carried out on the passivated monocrystalline silicon sheet in a wet method etching tank for removing PN junctions on the back side; and (5) a PECVD method is utilized for depositing silicon nitride on the front surface of the monocrystalline silicon sheet, and electrode printing and sintering are carried out. The method has the advantages that the compactness is good, the good passivation effect is reflected, and the photoelectric conversion efficiency of the monocrystalline silicon cell is obviously improved.

Description

technical field [0001] The invention relates to the related technical field of solar monocrystalline silicon cells, in particular to a method for preparing monocrystalline silicon surface passivation cells. Background technique [0002] In order to reduce the cost of solar cells, the thickness of silicon wafers is gradually reduced. When the diffusion length of the minority carriers is greater than the thickness of the silicon wafer, the influence of the recombination rate on the upper and lower surfaces of the cell on the efficiency becomes more important. The high recombination rate on the surface of silicon seriously restricts the photoelectric conversion efficiency of single crystal silicon solar cells. Passivation technology on the surface of crystalline silicon can reduce the recombination rate on the surface of crystalline silicon, thereby improving the photoelectric conversion efficiency of crystalline silicon solar cells. [0003] In the existing passivation techno...

AI Technical Summary

Problems solved by technology

[0005] The silicon dioxide film prepared by thermal oxidation has poor conductivity, which increases the contact resistance between the gate line and the silicon base, thereby increasing the series resistance and reducing the fill factor, which affects the further improvement of photoelectric conversion efficiency.