Method for manufacturing a gate structure incorporating aluminum oxide as a gate dielectric

摘要

A method for forming a gate structure begins by preparing a semiconductor substrate provided with an isolation region formed therein. An ultra thin SiO2 layer is thermally grown on top of the semiconductor device by using a wet H₂/O₂ or a dry O₂ at a temperature ranging from approximately 650° C. to approximately 900° C. And then, an Al layer is deposited on top of the semiconductor substrate and annealed in the presence of oxygen gas or nitrous oxygen to convert the Al layer into an Al₂O₃ layer. Thereafter, a conductive layer is formed on top of the Al₂O₃ layer. Finally, the conductive layer is patterned into the gate structure.