Effective Light Management in Thin Silicon Wafers

Crystalline silicon (c-Si)-based photovoltaics have dominated the global market share over the past decade. To progress toward utility-scale adoption, cost reduction plans are necessary, in which one option is to reduce the silicon material used. This comes at a cost of lower photo-absorption and generation, particularly for near-infrared photons due to their much higher absorption depth as compared to short-wavelength photons. In this chapter, the different methods to enhance light trapping for near-infrared photons are mentioned, and in particular the methodology on the proper design of a one-dimensional conductive distributed Bragg reflector (DBR) scheme is introduced. Both experimental and simulation results in this chapter consistently demonstrate the feasibility of integrating a conductive DBR scheme at the rear of a heterojunction silicon wafer solar cell (a type of c-Si-based photovoltaics technology) for enhanced photo-generation at the target long-wavelength regions (i.e., 900 ± 200 nm). The methodology presented here can be easily extended to other target wavelengths of interest and also not limited to solar cells applications alone.