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. 07, 1999
Filed:
Sep. 24, 1997
Reza Kazerounian, Danville, CA (US);
Waferscale Integration, Inc., Fremont, CA (US);
Abstract
A dual bit memory cell includes a substrate, a gate unit and left and right diffusions implanted into the substrate on the outer sides of the gate unit such that a channel exists under the gate unit and between the left and right diffusions. The gate unit includes a control gate and left and right separately programmable floating gates located on the left and right sides of the control gate. Each floating gate controls a short portion of the channel. The left diffusion acts as a drain and the right diffusion acts as a source when reading the value stored in the right floating gate and the right diffusion acts as a drain and the left diffusion as a source when reading the value stored in the left floating gate. In one embodiment, the floating gates are formed of polysilicon spacers.