Substrate engineering for high efficiency thin film solar cells

The design considerations for a spectra modifying, light scattering layer for amorphous silicon solar cells were investigated. Efficient commercially available phosphors absorb one near IR photon and one near UV photon and emit one photon in the visible spectrum. Thereby such phosphors offer the possibility to convert two poorly utilized portions of the solar spectrum to photons that are converted to electric energy with high quantum efficiency in amorphous silicon-based solar cells. Large band gap, conductive, a-SiC:H and a-SiN:H are attractive matrices for phosphors as scattered light and emitted photons are thereby directed towards the underlying solar cell structure.