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:
Sep. 12, 1995
Filed:
Oct. 28, 1991
Fumitoshi Toyokawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A method of manufacturing a silicon single crystal substrate with the back surface thereof having deposited polycrystalline silicon. The method includes steps of depositing polycrystalline silicon on a coarsely polished silicon single crystal substrate, mirror surface finish polishing one substrate surface and carrying out a high temperature thermal treatment. The thermal treatment is carried out either prior or subsequent to the polycrystalline silicon deposition step. The thermal treatment has the effects of causing diffusion of interstitial oxygen Oi from the substrate surface to the outside and also causing contraction and vanishing of Oi precipitation nuclei in the substrate.