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:
Jun. 26, 1990
Filed:
Apr. 27, 1989
Richard J Hollingsworth, Concord, MA (US);
Donald E Nelsen, Winchester, MA (US);
Digital Equipment Corporation, Maynard, MA (US);
Abstract
A chip having field effect transistors which have differing threshold voltages determined in a single masking step and a method of making the chip provides a chip usable at both cryogenic and room temperatures without a costly additionaly masking step. The chip has devices with low threshold voltages that are therefore optimized for performance at low temperatures, and devices with high threshold voltages that are optimized for performance at higher temperatures. Such high threshold voltage devices are also usable, though sub-optimally, at lower temeperatures such as cryogenic temperatures. The two sets of devices have their threshold voltages determined in a single masking step, with the higher threshold voltage values being provided during this step by reducing the width of a device to produce a parasitic effect.