Phonon-assisted absorption enhancement in amorphous Si solar photovoltaic

In electronics and photonics phonons hinder transport or present inefficiency, but here we scrutinized them to improve the photovoltaic solar-cell performance. Phonons account for a significant portion of the temperature-dependent absorption coefficient of a-Si:H (hydrogenated amorphous silicon), e.g., at 300 K, between 1.5 to 2.2 eV. We propose and theoretical treat introduction of suitable a-Si_xSn_1-x alloy, choosing Sn for desired phonons to assist in the absorption of photons and increase the overall efficiency of the cell. Phonons are essentially thermally induced vibrations within the semiconductor lattice. The spectra of these vibrations are characterized by (a) structure and (b) force constant between atoms (inter-atomic potential). Here we show that Sn alloy can be used to enhance phonon-assisted absorption which in turn may increase the current generation.