Monolithically integrated read-only memory
US4450537A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 19, 1981 |
| Grant date | May 22, 1984 |
| Priority date | — |
| Expiry date | Aug 19, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C17/16
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A monolithically integrated read-only memory has a plurality of word lines, read lines which cross the word lines to form intersections, and field effect transistors connected to the read and word lines, these transistors being selectable via the word lines and functioning as coupling elements between the read lines and circuit point carrying a reference potential. Means are provided for selectively altering a charge state of a gate insulating layer of transistors at certain predetermined selected intersections, the altered charge states changing a threshold voltage of the transistor so as to determine whether or not it is employed as a coupling element. Preferably electron beam scanning is employed to change the charge state of the gate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.