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:
Sep. 04, 2001
Filed:
Nov. 29, 1999
Dharam Pal Gosain, Kanagawa, JP;
Kazumasa Nomoto, Kanagawa, JP;
Jonathan Westwater, Kanagawa, JP;
Miyako Nakagoe, Kanagawa, JP;
Setsuo Usui, Kanagawa, JP;
Takashi Noguchi, Kanagawa, JP;
Yoshifumi Mori, Kanagawa, JP;
Sony Corporation, Tokyo, JP;
Abstract
While a storage region,has of many dispersed particulates (dots) (,), the surface density of the particulates (,) is set to be higher than that of structural holes (pin holes) produced in a tunnel insulating film (,), or the number of the particulates (,) in the storage region (,) is set to five or more. While a conduction region (,) is formed by a polysilicon layer (,) having a surface roughness of 0.1 nm to 100 nm, the number of the particulates (,) in the storage region (,) is set to be larger than the number of crystal grains in the conduction region (,). Even when a defect such as a pin hole occurs in the tunnel insulating film (,) and charges stored in a part of the particulates are leaked, the charges stored in the particulates formed in a region where no defect occurs are not leaked. Thus, information can be held for a long time.