Patent ID: 7553726
Filing Date: 2009-06-30
Classification: H01L

Abstract:
1. A method of fabricating a nonvolatile memory device, comprising: forming pairs of separate floating gates on a semiconductor substrate; forming control gates on the semiconductor substrate, each control gate partially overlapping one of the floating gates; conformally forming a buffer film on a surface of the semiconductor substrate on which the floating gates and the control gates are formed; injecting ions into the semiconductor substrate between the pairs of separate floating gates to form a common source region partially overlapping each floating gate of the respective pair of the floating gates; depositing an insulating film on the buffer film; etching the buffer film and the insulating film at side walls of the floating gates and the control gates to form spacers at the side walls of the floating gates and the control gates; and forming drain regions in the semiconductor substrate at a respective side of the control gates other than a side of the control gates where the common source region is formed.