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. 31, 1993
Filed:
Jul. 28, 1992
Tsutomu Satoh, Niigata, JP;
Kouichi Nishimaki, Niigata, JP;
Naoetsu Electronics Co., Niigata, JP;
Abstract
This invention relates to a process and an apparatus for making a substrate of a semiconductor of a monolithic silicon wafer, or the like, for use as a discrete element such as a transistor, diode, or the like. In particular, the invention is directed to re-slicing the silicon wafer into two further pieces, to dope impurity diffused layers on both sides but not to provide any impurity diffused layer in the core portion of the silicon wafer. The re-slicing process is performed from substantially the center portion of its core thickness of the wafer so as to provide each re-sliced surface as a plain surface without any impurity diffused layer and for doping a further new impurity diffused layer, so as to obtain two pieces of a substrate as discrete elements simultaneously from one piece of the wafer by the re-slicing process and apparatus of the invention.