Semiconductor memory device and method of manufacturing the same
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Apr 16, 2002
Grant Date -
Jul 26, 2001
app pub date -
Feb 6, 2001
filing date -
Apr 28, 1989
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
A gate oxide film is formed on a surface of a semiconductor substrate. A tunnel insulating film having a thickness smaller than that of the gate insulating film is formed in a portion thereof corresponding to a tunnel region. A first silicon film having a low impurity concentration is formed on the gate insulating film. A second silicon film having an impurity concentration higher than that of the first silicon film is formed on the first silicon film so as to be connected thereto. A third silicon film is formed on the second silicon film through an insulating film. The second and third silicon films are formed into floating and control gates, respectively, thereby forming a semiconductor memory device.
First Claim
Other Claims data not available
