Development of a Transparent Passivated Contact as a Front Side Contact for Silicon Heterojunction Solar Cells

We present a new transparent passivated contact concept utilizing microcrystalline silicon carbide and an ultra-thin silicon tunnel oxide ( \mu \mathrm{c} -SiC:H(n)/SiO) for the front side of silicon heterojunction solar cells. We investigated different oxidation agents in combination with selected deposition conditions of the \mu \mathrm{c} -SiC:H(n) to find the ideal parameters for high passivation quality and high conductivity. Implied open-circuit voltages up to 728 mV were achieved without any post-deposition treatment e.g. high temperature or forming gas annealing. The transparent passivated contact solar cells show increased quantum efficiency in the short wavelength range as compared to the conventional silicon heterojunction solar cells. These insights show the great potential for the transparent passivated contact front side.