The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 18, 2004
Filed:
Nov. 27, 2001
Satoru Yamagata, Fukuyama, JP;
Masanori Yoshimi, Fukuyama, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
In a method for manufacturing a memory cell of a nonvolatile semiconductor memory, a floating gate, first insulating film and control gate are successively stacked on a tunnel oxide film formed on a substrate of the nonvolatile semiconductor memory. The control gate, the first insulating film and the floating gate are patterned in stripes. Subsequently, a damaged portion of the tunnel oxide film immediately below a sidewall of the floating gate is removed by isotropic etching. A second insulating film is deposited to cover the control gate, sidewalls of the first insulating film, the floating gate and the tunnel oxide film. Thereby, a variation in threshold voltages between memory cells is suppressed.