The JCT buried BSF silicon solar cell a model of simplicity and high efficiency

The term BSF is defined as an electric field region created by diffusion of a dopant of the same type as present in the base region of a solar cell into the back surface of the cell. The buried BSF is then defined as a BSF buried beneath a heavily doped, multicrystalline, silicon-silicon oxide layer. A simple process for fabricating a buried BSF and an optimum emitter for an n/sup +/, p, p/sup +/ silicon solar cell is described. The buried BSF, at present, provides 0.63 volt Voc, under AM1 illumination, and 1000 /spl mu/m base minority carrier diffusion length when made in 100 ohm cm silicon. An attempt is being made to utilize the buried BSF to achieve a useful high efficiency cell, possessing long term reliability and acceptable manufacturing cost.