Patent ID: 6897104
Filing Date: 2005-05-24
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device comprising the steps of: forming a first semiconductor domain and a second semiconductor domain isolated from each other by forming a field dielectric layer for device isolation selectively on a surface of a silicon semiconductor substrate; forming a silicon dioxide film on each of surfaces of the first semiconductor domain and the second semiconductor domain; removing the silicon dioxide formed on the surface of the second semiconductor domain for exposing the surface of the second semiconductor domain; forming a nitrogen-containing silicon oxide film on the surface of the first semiconductor domain and forming a silicon nitride film on the surface of the second semiconductor domain by nitriding the silicon dioxide in the first semiconductor domain, and the exposed surface of the second semiconductor domain; forming an oxygen-containing silicon nitride film on the surface of the second semiconductor domain by oxidizing the silicon nitride film; and forming a gate electrode on each of the nitrogen-containing silicon oxide film and the oxygen-containing silicon nitride film; wherein the thickness of the silicon nitride film before the oxidation in the step of forming the oxygen-containing silicon nitride film is 1.5 nm or less, and an equivalent oxide thickness (EOT) of the oxygen-containing silicon nitride film is 2.5 nm or less.