Patent ID: 8748222

Claim:
A method for forming an oxide thin film transistor, comprising: providing a substrate; forming a gate electrode, a source electrode, a drain electrode and an oxide semiconductor layer on the substrate, the oxide semiconductor layer being formed on a surface of the gate electrode, and the source electrode and the drain electrode being respectively formed on two opposite sides of the oxide semiconductor layer, the oxide semiconductor layer being composed of indium gallium zinc oxide, a flow rate of argon gas used in a process for forming the oxide semiconductor layer being 50 SCCM, an electric power used in the process for forming the oxide semiconductor layer being 3.5 KW, and a volume ratio of oxygen in a reacting gas for forming the oxide semiconductor layer being 9%; and performing a depositing process to form at least one dielectric layer of silicon oxide, a reacting gas for the depositing process comprising silane and nitrous oxide, a flow rate of nitrous oxide being in the range from 10 to 200 SCCM, wherein a thickness of the dielectric layer of silicon oxide is in the range from 300 Å to 5000 Å, the depositing process is a plasma enhanced chemical vapor deposition (PECVD) process, an electric power applied in the PECVD process is in the range from 0.5 KW to 10 KW.