Influence of different Parameter Profiles on the Formation of Aluminum Back Surface Field (Al-BSF) using for HIT Solar Cell

摘要

The aluminum back surface field used in p-type substrate hetero-junction with intrinsic thin film (HIT) solar cell is studied in this paper. The enhancement of material quality and the decrease of wafer thickness will make it necessary to passivate the back surface. It simply states the principle and formation process of aluminum back surface field, and studies the evenness of back surface field because it is necessary for high efficiency solar cell. Screen-printing and rapid thermal annealing were used to make aluminum back surface field to gain low recombination on the backside of solar cells. In this experiment, we analyze Al-BSF formed by taking different times and temperatures in which the temperaturernvaried in the range between 620℃ and 940 ℃ step 80℃ and the time varied from 60 seconds to 180 seconds with a steprnof 30 seconds. Minority carrier lifetime with the back surface field was measured by microwave photoconductive decay (μ-PCD) device, analyze and get the optimal parameters of forming Al-BSF and further improve conversion efficiency of silicon solar cell.