Patent ID: 6534821
Filing Date: 2003-03-18
Classification: H01L

Abstract:
A split-gate flash with a protruding source structure comprising:providing a semiconductor substrate having active and passive regions defined; a source region and a drain region within said substrate; a pad oxide layer over said substrate; a protruding source structure with vertical walls having a top portion and bottom portion formed over said source region, the top portion comprising a poly-oxide having a thickness between about 1900 to 2100 Ã¥; a floating gate oxide layer formed over said vertical walls of said protruding source structure; a thin vertical floating gate having a bottom edge over said floating gate oxide; a thin and sharp poly-tip at said bottom edge of said vertical floating gate; an inter-gate oxide over said vertical floating gate, including said sharp poly-tip; and a spacer control gate over said inter-gate oxide layer.