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:
Dec. 25, 1979
Filed:
Dec. 06, 1973
Warren C Rosvold, Sunnyvale, CA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A method of making a number of semiconductor diodes on a single wafer without breakage during handling and processing, comprising the steps of forming a plurality of mesas on one surface of an intrinsic substrate, diffusing a selected first conductivity-type region into each mesa, coating the front surface of the substrate and mesas with oxide, chemically milling recesses into the opposite side of the substrate in alignment with the mesas to a predetermined depth where the mesas are each supported by a thin annular area of substrate material permitting transfer of the device into an epitaxial reactor, gas etching the recesses to a depth beyond the oxide interface to physically separate the mesas from the substrate material, growing a thin epitaxial layer of opposite conductivity type over the back surface of the device, applying ohmic contacts to the device, and separating the individual mesas.