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:
Aug. 30, 1977
Filed:
May. 03, 1976
Robert K Jones, Centerville, OH (US);
Harry Sue, Chicago, IL (US);
Teletype Corporation, Skokie, IL (US);
Abstract
A read-only memory is manufactured from a matrix or array of multilayer electrical devices, each of which includes at least one metallic layer, a portion of which contacts a doped semi conductor region. The metallic layers are controllably and rapidly thinned down and decreased in cross-sectional area in the vicinity of the doped regions to form fusible links, thus producing a ROM starting product. Fusible link formation is enhanced by the use of an etchant for the metallic layer which forms an electrochemical cell in conjunction therewith and with the semiconductor and the doped region. Any metallic layers not contacting a doped region are also etched by the etchant, but at the much slower 'chemical rate'. Following the production of the starting product, a ROM may be produced by the selective application of voltages to selected fusible links, the I.sup.2 R heating of the links fusing them, or blowing them out. In a preferred embodiment, the electrical devices are MOSFETS.