Distributed local boron-doped double-face photoreceptive crystalline silicon solar cell and preparation method thereof

Abstract

The invention discloses a distributed local boron-doped double-face photoreceptive crystalline silicon solar cell and a preparation method of the distributed local boron-doped double-face photoreceptive crystalline silicon solar cell. The cell comprises a silicon substrate, an N-type doping region is arranged on the front face of the silicon substrate, a front anti-reflection passivation coating is arranged on the N-type doping region, and a back passivation coating is arranged on the back face of the silicon substrate. The preparation method includes the following steps that part of the back passivation coating is removed on the back passivation coating through distributed short line patterns, the silicon substrate is exposed, and then a plurality of removal passageways are formed; then boron-silicon paste is locally printed so as to cover the removal passageways; then a back electrode layer and a front electrode layer are respectively printed and dried; high-temperature sintering is conducted, the boron-silicon paste in the passageways is removed, a distributed P-type boron heavy doping region is formed on the contact interface of the removal passageways and the silicon substrate, and then a P-type boron heavy doping layer is formed; in the high-temperature sintering process, the front electrode layer and the back electrode layer are formed at the same time. The recombination rate of minority carriers on the contact interface are reduced, open-circuit voltages and conversion efficiency of the cell can be improved, the coating opening area is reduced, and the surface recombination rate is further reduced, wherein the minority carriers are arranged on the back face of the solar cell.

Description

technical field [0001] The invention relates to a distributed localized boron-doped double-sided photosensitive crystal silicon solar cell and a preparation method thereof, belonging to the technical field of solar cell preparation. Background technique [0002] At present, the local aluminum back field of crystalline silicon solar cells is a research hotspot in the photovoltaic industry, and is generally considered to be a mass-producible technology to improve the conversion efficiency of crystalline silicon solar cells. At present, the conventional process is to use AlO x / SiN x :H or SiO 2 / SiN x :H laminated film passivates the back surface, opens the back film with laser or chemical etching in the pattern of parallel lines, and then prints aluminum paste on the entire surface. In the high temperature process, the aluminum and silicon in contact with the interface form a liquid alloy phase, and the liquid alloy phase solidifies during the cooling process, and a part ...

AI Technical Summary

Problems solved by technology

[0003] The limitations of this local aluminum back field cell are: 1. The back is doped with aluminum to form a local back field, and the doping concentration is only 1×10 18 cm -3 order of magnitude, and the doping depth is shallow, which cannot prevent the recombination of minority carriers from passing through the local back field to reach the metal contact; 2. The back doping occupies a large overall area, which reduces the area of ​​the passivation film, resulting in additional surface recombination

Images