Hydrogenated amorphous silicon prepared by laser-induced chemical vapor deposition of silane for solar-cell applications

Hydrogenated amorphous silicon (a-Si:H) deposited by laser-induced chemical vapor deposition (LICVD) from SiH4 gas is a promising material for photovoltaic applications. Growth proceeds by pyrolysis of the reactant gases and low substrate temperatures permit retention of adequate H. Controlled n- and p-type doping of LICVD a-Si:H has been achieved by mixing PH3 and B2H6, respectively, into the reactant gas. Conductivity activation energies of less than 0.2 eV are obtained for both conductivity types and this indicates that high open-circuit voltage can be achieved in LICVD solar cells. Undoped LICVD a-Si:H appears to be more intrinsic than glow-discharge material, indicating a different detect structure. Growth rate, stress, electron spin resonance and hydrogen content data are also presented.