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:
Apr. 26, 1983
Filed:
May. 04, 1981
Roger S Countryman, Jr, Austin, TX (US);
Paul T Lin, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A process is disclosed for fabricating a MOS ROM which allows programming of the ROM late in the process sequence. A conventional silicon gate process is used to fabricate the devices up through the step of patterning the polycrystalline silicon gate electrode. Selected devices in the array are then programmed to an off-state by fabricatng those devices with either the source or drain region offset from the gate electrode. This is accomplished by a programming mask which, together with the gate electrode, provides selective location of the source or drain regions. Devices having an offset source or drain are off-state devices, while those having a normal source and drain function conventionally and conduct when a read voltage is applied.