The effect of front and rear surface recombination velocities on the photocurrent of a buried emitter silicon solar cell

Abstract

Analytical work on the buried emitter solar cell (BESC) has been carried out based on the model presented previously by various researchers. The minority carrier distribution and the photocurrent contribution from the front region and also the rear region of the cell have been studied, taking into consideration the effects of front surface and rear surface recombination velocities. It is observed from these theoretical studies that reducing these recombination velocities, there is significant improvement in the photocurrent contributions form these regions. This emphasizes the role of a back surface field (BSF) in such devices. It may be mentioned here that in some recent experimental studies on new types of BESC solar cells, heavily doped BSF regions have been included by investigators.

Keywords

• Buried emitter silicon solar cell; surface recombination velocity; photocurrent; minority carrier concentration

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