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. 28, 2015
Filed:
Jul. 08, 2013
Dow Corning Corporation, Midland, MI (US);
Mark Loboda, Bay City, MI (US);
Dow Corning Corporation, Midland, MI (US);
Abstract
A method of forming an SiC crystal including placing a seed crystal of SiC in an insulated graphite container; placing a source of Si and C atoms in the insulated graphite container, where the source of Si and C atoms is for transport to the seed crystal to grow the SiC crystal; placing the container into the furnace; heating a furnace to a temperature from about 2,000° C. to about 2,500° C.; evacuating the furnace to a pressure from about 0.1 Torr and about 100 Torr; filling the furnace with an inert gas; and introducing dopant gas into the furnace with a controlled flow so as to form a plurality of stratified layers wherein each layer has dopant concentration different from a layer directly below and a layer directly above it. A 4H-SiC crystal made by the method. A 4H-SiC substrate cut from the SiC crystal made from the method.