Low-temperature large-grain poly-Si direct deposition by microwave plasma enhanced chemical vapor deposition using SiH₄/Xe

Polycrystalline silicon is grown at a temperature of 300 °C by microwave-excited plasma enhanced chemical vapor deposition using SiH₄/Xe. The grain size measured by x-ray diffraction is about 25 nm. High-density (> 10¹² cm^-3) plasma having very low electron temperature (<1 eV) is excited by microwave irradiation using radial line slot antenna. We present the implementation of this system for the growth of poly-Si. Low-energy (3 eV), high-flux ion bombardment utilizing xenon ion on a growing film surface activates the film surface and successfully enhances surface reaction/migration of silicon, resulting in high quality film formation at low temperatures.