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:
Mar. 21, 1995
Filed:
Jun. 27, 1994
Shih-Wei Sun, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A mixed thin-film and bulk semiconductor substrate (10, 30) for integrated circuit applications is made with two different processes. In the first process, a standard wafer (11) is masked around its periphery (14). The internal unmasked portion (16) is implanted with an insulating species to form a buried dielectric layer (18), thus forming a mixed thin-film and bulk semiconductor substrate. Alternatively, a thin-film wafer may be masked on an internal portion (36) and then etched to expose a portion (40) of the underlying bulk substrate (11') around the periphery of the wafer. An epitaxial layer (50) is then grown to build up the exposed bulk portion to form the mixed substrate. An isolation region (24, 52, 46, 54) is formed at a boundary between the thin-film portion and the bulk portion. Devices (27, 28, 28') having different voltage requirements may then be formed overlying appropriate portions of the mixed substrate.