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:
Mar. 01, 1988
Filed:
Sep. 27, 1984
Bruce A Kauffmann, Jericho, VT (US);
Chung H Lam, Troy, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A non-volatile dynamic memory cell in which the non-volatile element has two different areas for electron injection, such that direct overwriting of previously stored non-volatile data is permitted without an intervening erase cycle. The non-volatile storage element is a floating gate electrode which has dual control gates disposed thereon. Each control gate includes a layer of dual electron injector structure (DEIS) and a polysilicon gate. When writing a '0' from the volatile storage capacitor to the floating gate, one of the control gates removes charge from the floating gate. To write a '1', the other control gate injects charge into the floating gate. The above charge transfer does not take place if the previously stored logic state and the logic state to be written in are identical. In order to minimize the adverse effects of process variations, the gate electrode of the word line device is electrically in common with one of the control gates.