Patent ID: 6372578
Filing Date: 2002-04-16
Classification: H01L

Abstract:
A method of manufacturing a non-volatile semiconductor device, having a floating gate overlying a tunnel insulating film set on a silicon substrate and a control gate overlying an inter-gate insulating film set on said floating gate; which comprises the steps of:forming a silicon oxide film on a surface of the silicon substrate and subsequently applying a heat treatment thereto in an atmosphere of a nitriding gas containing nitrogen oxide so as to form a nitridation region and thereby forming a tunnel insulating film; wherein in said heat treatment performed in the atmosphere of the nitriding gas, so that a maximum nitrogen atomic concentration in the tunnel insulating film that is to be formed becomes equal to or greater than an acceptable maximum nitrogen atomic concentration capable to provide given acceptable holding characteristics, the pressure of said nitriding gas and the temperature of heat treatment are controlled on the basis of a pre-formed relationship equation between the thickness of the tunnel insulating film and the acceptable maximum nitrogen atomic concentration, for a prescribed thickness of the tunnel insulating film that is to be formed.