Simulation study of the tunnel junction position effect on the parameters of the In_xGa_1-xN dual junction solar cell

Abstract

The present work presents a SILVACO-Atlas numerical simulation to investigate the effect of the tunnel junction position on the performance of InxGa1-xN double-junction solar cells under AM1.5 solar illumination. The proposed cell is composed of two PN sub-cells, an upper sub-cell in In0.1Ga0.9N and a lower sub-cell in In0.4Ga0.6N for the p-type and In0.2Ga0.8N for the n-type, connected by a tunnel junction in In0.4Ga0.6N. The cell offers a remarkable open-circuit voltage value of about 3.9 V and a good fill shape value of about 93. A cell with a small overall thickness can offer better transfer efficiency than a cell with a large thickness if the tunnel junction position is carefully chosen. The proposed cell can achieve a transfer efficiency of around 18% with an overall thickness of 0.652 µm.