Studies On Selective Emitting Mono-crystalline Silicon Solar Cells By Etching

ABSTRACT:In this thesis, I mainly study the selective emitting mono-crystalline siliconsolar cell by etching.The core of selective-emitter is heavily/lightly-doped emitter zone in the cell surface. In this thesis, we make sure the new diffusion processes and etching processes of selective emitting Mono-Crystalline siliconsolar cell:the square resistance of heavy doping is 35Ω/□, the square resistance of light absorption region after etching is best between 70 and 105Ω/□. Contrapuntal printing between mask printing and printed electrode is very important to selective emitting mono-crystalline siliconsolar cell. In this thesis, I find the influence of Printing machine and scraper blade to the contrapuntal printing by experimental analysis:when I use the same printing machine, silver screen printing plate and scraper blade, the contrapuntal printing will have a high precision. When I use the same printing machine, silver screen printing plate, but not the same scraper blade, the contrapuntal printing still have room for improvement,but basically satisfy requirements.At last, I compare the experimental films to normal films, and I study the influence of selective emitting mono-crystalline siliconsolar cell to the basic characteristic parameters. I find compare with the conventional process, selective emitting mono-crystalline siliconsolar cell increase 0.008v in open-circuit voltage,0.31 A in short-circuit current,0.89 in FF and 0.72% in efficiency.