Selective Boron Diffusion Without Masking Layer Using Boric Acid for Solar Cell Emitter Formation
Abstract
In this article, we have used boric acid source to form the boron emitter in a selective way. And, the conditions of boron diffusion process were investigated. It was found that for 5% boric acid in DI water, the spinning of 3000 rpm for 15 sec and dry out process at 200°C are the most appropriate conditions. Also, in this study, by using boric acid source, a selective doping method was developed. Therefore, it can be possible to have both light and heavy (under contacts) dopings on different areas of the wafer but without any extra masking layer (e.g. silicon dioxide) and undergoing only one drive-in process.
Keywords
Boric acid, Emitter formation, Solar cell