High-density microwave plasma for high-rate and low-temperature deposition of silicon thin films

摘要

A novel high-density microwave plasma utilizing a spokewise antenna was produced and applied for high-rate and low-temperature deposition of hydrogenated microcrystalline silicon (μc-Si: H) film. The plasma maintains a uniform state, i.e., high electron density, n{sub}e> 10{sup}11 cm{sup}(-3) and low temperature, T{sub}e of 2-2.5 eV in pure Ar plasma over 20 cm in a diameter. High deposition rate was achieved of 47 A/s in the growth of highly crystallized and photoconductive μc-Si: H film at the axial distance, Z = 6 cm from the quartz glass plate from SiH{sub}4 and Ar without the use of H{sub}2 dilution method at low substrate temperature, T{sub}s of 250℃. The effects of the total pressure, H{sub}2 dilution ratio, flow rate of SiH{sub}4, Fr(SiH{sub}4) and the axial distance, Z from the quartz glass plate on the μc-Si: H film deposition are discussed along with the plasma diagnostics.