Large area deposition of hydrogenated amorphous silicon by VHF-PECVD using novel electrodes

A novel discharge source capable of depositing a-Si:H films on large area has been developed. This discharge source consists of "U" shaped loop-antenna. A number of antennas were arranged in parallel to each other, forming one plane in front of a substrate. a-Si:H was deposited on a 1000 mm/spl times/500 mm glass substrate at 0.4 nm/sec using VHF (81 MHz) plasma. The nonuniformity of deposition rate in the direction along the antenna was about /spl plusmn/80% when the VHF power was equally fed to each antenna with a continuous mode. Whereas, this nonuniformity could be suppressed to less than /spl plusmn/10% by controlling the power feeding method with a pulse mode.