Influence of base doping level on the npn microstructure solar cell performance: A TCAD study

Silicon industry has a mature learning curve which is the driver for 90% share of the PV market. Yet, the cost/m2 of the planar crystalline silicon solar cell is still high. To reduce the cost of silicon-based solar cells, heavily doped wafers can be used in a proposed npn microstructure in which photoexcited carries are vertically generated while the collection of carriers is accomplished in the lateral direction. In this work, we report on the influence of the heavily p + base doping concentration, Na, on the performance of the cell for different base widths. All simu-lations are performed by using SILVACO TCAD under AM1.5 illumination. The results show that for Na extending from 5 x 10(17) cm(-3) to 2 x 10(19) cm(-3), the cell could achieve a competitive efficiency, from 15.4% to 9%, respectively.