N-type microcrystalline silicon carbide – μc-SiC:H(n) – may exhibit excellent optoelectronic properties when it is deposited by a hot-wire chemical vapor process in silicon-based thin-film and silicon heterojunction solar cells.
This costly wide-bandgap material, is thought to exhibit excellent optoelectronic properties for use as a solar cell layer. When deposited using a hot-wire chemical vapor process it could be used to produce high performance silicon thin film or heterojunction cells, thanks to high optical transparency and a suitable refractive index – two factors which reduce parasitic absorption losses on light trapping and reflection losses.
Despite this potential, the technology has so far seen only limited uptake, as the materials required are costly, and producing reliably performing devices is challenging: deposition conditions for growing highly transparent n-type microcrystalline silicon carbide on solar cells tend to cause strong deterioration in the underlying silicon layers.
However, an international research team led by Germany’s Institute of Energy Research 5 – Photovoltaic (IEK-5), has investigated how hot wire chemical vapor deposition (HWCVD) of n-type microcrystalline silicon carbide may be applied to improve the performance of interdigitated back contact (IBC) solar cells.