Patent ID: 7365430
Filing Date: 2008-04-29
Classification: H01L

Abstract:
1. A semiconductor device comprising: an element isolation film which is formed in an element isolation region of a semiconductor substrate, the element isolation film comprising protrusions that project above the semiconductor substrate; a gate insulating film formed on the semiconductor substrate between the protrusions of the clement isolation film; a first polysilicon layer of a cylindrical structure, which is formed on the gate insulating film between the protrusions of the element isolation film to form a floating gate; a second polysilicon layer formed on an inner wall of the first polysilicon layer, wherein the second polysilicon layer is formed on a concave portion of the first polysilicon layer; a metal layer formed within the second polysilicon layer; a barrier metal layer formed between the metal layer and the second polysilicon layer, wherein the barrier metal layer comprises one of WN and TiSiN; and a source/drain formed on the semiconductor substrate at an edge of the first polysilicon layer.