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:
Nov. 10, 1992
Filed:
Sep. 27, 1990
Hiroaki Hazama, Kanagawa, JP;
Kazumi Nishinohara, Tokyo, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A nonvolatile memory cell comprises a semiconductor substrate of first conduction type, a high-concentration impurity region of second conduction type formed on the semiconductor substrate and connected to a bit line, an insulation film in which carrier traps are formed, and a gate electrode that is opposite the high-concentration impurity region across the insulation film and connected to a word line. Carriers are captured by, and released from, the carrier traps formed in the insulation film, in response to bias voltages applied to the word and bit lines. Information stored in the memory cell depends on whether or not the carrier traps are holding carriers. The information is read out of the memory cell as the difference of a tunneling current flowing between the semiconductor substrate and the high-concentration impurity region.