Characteristics of SiO2 film grown by atomic layer deposition as the gate insulator of low-temperature polysilicon thin-film transistors

Abstract

SiO2 films were prepared by atomic layer deposition (ALD) technique, and their physical and electrical properties were characterized for being applied as a gate insulator of low-temperature polysilicon thin-film transistors. ALD SiO2 films were deposited at 350-400°C using alternating exposures of SiH2Cl2 and O3/O 2, and the characteristics of the deposited films were improved with increasing deposition temperature. The ALD films deposited at 400°C exhibited integrity, surface roughness and leakage current better than those of the conventional plasma-enhanced chemical vapor deposition (PECVD) films.