Improving surface passivation capability of silicon heterojunction solar cells with amorphous silicon by optical emission spectrometry

The intrinsic a-Si:H thin film is the key to the high efficiency heterojunction silicon solar cells. The transient instability after plasma ignition decreases the minority carrier lifetime of passivated silicon wafer at the same deposition process. The capability to passivate the silicon surface of a-Si:H thin films deposited at different hydrogen flow rate is investigated. The results show the passivation capability at higher hydrogen flow rate is poorer. The decrease of H_α*, H_β* and SiH* emission intensity in plasma is not easier to passivate the silicon surface.