3-D Simulation of Interdigitated-Back-Contact Silicon Solar Cells With Quokka Including Perimeter Losses

Abstract

An interdigitated-back-contact (IBC) version of Quokka, a recently developed free and fast solar cell simulation program, is presented. It is capable of simulating IBC unit cells with a variety of interdigitated contact and diffusion patterns in both 2-D and 3-D. The program is evaluated by comparing simulated and experimental current–voltage ( I–V ) curves of high-efficiency IBC solar cells. The simulations include the perimeter effects of edges and busbars by simulating the inner unit cell in 3-D, and accounting for the edges and busbars by 2-D unit cell approximations. The simulation agrees well with the experiment under 1-sun conditions with different aperture areas. Furthermore, simulations of the inner unit cell are successfully validated against Sentaurus Device, for both the I–V curve and detailed free energy losses at maximum power point. The results evidence the validity of the quasi-neutral and conductive-boundary approximations employed by Quokka for fast simulation of IBC solar cells.