Patent ID: 7189661

Claim:
A method of forming an insulating layer having silicon oxynitride comprising: increasing a predetermined initial temperature up to a first treatment temperature, when a substrate to be treated is loaded into a processing room, with an atmosphere of the processing room maintained with a first pressure; supplying a first treatment gas into the processing room to form a silicon oxide layer on the substrate to be treated, with an atmosphere of the processing room maintained at the first treatment temperature; increasing a temperature of the processing room up to a second treatment temperature after the silicon oxide layer is formed, and supplying a second treatment gas for performing a nitridation inside the processing room, to perform an annealing process, thereby changing a portion of the silicon oxide layer to silicon oxynitride; and decreasing a temperature of the processing room to a third treatment temperature after the annealing process, and supplying a third treatment plasma gas into the processing room with the atmosphere of the processing room maintained with a second pressure, and performing a plasma treatment process for changing an additional portion of the silicon oxide layer to silicon oxynitride.