Amorphous Si (a-Si) solar cell has a band gap of ~1.6 eV and absorption length for the red and infrared solar photons exceed 1 µm and 100 µm, respectively [14] and [15]. The hole diffusion length for a-Si:H is 300–400 nm, which limits the solar cell absorber layer thickness to less than hole diffusion length [16]. As the thickness of absorber layer is limited to a few nanometres, it is difficult to use these photons for efficient carrier collection. This limits the efficiency of solar cell. Thus, enhancing the light absorption is essential for better result, which is done by different techniques including back reflector or light trapping configurations.