Patent ID: 7148110

Claim:
A method of forming a semiconductor device comprising: forming a first sacrificial layer on a semiconductor substrate; forming a second sacrificial layer on the first sacrificial layer; patterning the second sacrificial layer to form an opening in the second sacrificial layer that exposes a portion of the first sacrificial layer; forming spacers of a first dielectric material on side walls of an opening of the second sacrificial layer; etching the first sacrificial layer using the second sacrificial layer and the spacers as a mask to expose a portion of the semiconductor substrate; filling the exposed region between the spacers with the first dielectric material to form a T-shaped structure of the first dielectric material on the semiconductor substrate; removing the first and second sacrificial layers such that the T-shaped structure remains on the semiconductor substrate; providing a first oxide layer on the semiconductor substrate; providing a nitride layer on the first oxide layer; etching the nitride layer and first oxide layer using the T-shaped structure as a mask such that a nitride layer pattern and a first oxide layer pattern remain under upper overlap portions of the T-shaped structure; providing a second oxide layer on the semiconductor substrate and the nitride layer pattern; providing control gates adjacent the second oxide layer; and forming first junction regions in the semiconductor substrate using the control gates as a mask.