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. 13, 1991
Filed:
Apr. 27, 1990
Arnold Reisman, Raleigh, NC (US);
Mark Kellam, Chapel Hill, NC (US);
Charles K Williams, Raleigh, NC (US);
Nandini Tandon, Durham, NC (US);
MCNC, Research Triangle Park, NC (US);
Abstract
A Maximum Areal Density Recessed Oxide Isolation (MADROX) process for forming semiconductor devices, in which forms an insulating layer is formed on a monocrystalline silicon substrate and a patterned polycrystalline silicon-containing layer is formed on the insulating layer. The substrate is then subjected to a low temperature plasma assisted oxidation to form recessed oxide isolation areas in the exposed regions of the substrate, with minimal encroachment under the patterned polycrystalline silicon-containing layer. The patterned polycrystalline silicon-containing layer acts as a mask, without itself being oxidized. Low temperature recessed oxide isolation regions may thereby be formed, without 'bird's beak' formation. Maximum Areal Density Bipolar and Field Effect Transistor (MADFET) devices may be formed, using the patterned polycrystalline silicon-containing layer as a device contact if desired.