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:
Feb. 05, 1991
Filed:
Dec. 30, 1988
Helmut Baumgart, Mahopac, NY (US);
Andre Martinez, Derry, NH (US);
North American Philips Corp., New York, NY (US);
Abstract
An improved technique for forming silicon-on insulator films for use in integrated circuits. The technique provides an improved encapsulation layer to enable in a reproducible way the zone melt recrystallization of such films. The encapsulation layer consists of a first layer of a doped SiO.sub.2 (silicate glass) on which a further layer of Si.sub.3 N.sub.4 is deposited. The doped SiO.sub.2 forms a fusible glassy material which is rendered semi-liquid and flows at the temperatures used in recrystallization. The softening of the encapsulation material accommodates volume expansion and eliminates the biaxial stresses in the layered structure. The Si.sub.3 N.sub.4 layer adds mechanical strength to the SiO.sub.2 layer and improves the wetting angle.