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:
Feb. 28, 1995
Filed:
Oct. 22, 1993
Shin-Etsu Handotai Kabushiki Kaisha, Tokyo, JP;
Abstract
To provide a method of making a SOI film having a more uniform thickness in a SOI substrate which makes it possible to keep the variance at .+-.0.3 micrometers or less throughout the entire surface of the substrate, even for SOI substrates with a SOI film thickness between 1 micrometer and 10 micrometers. The surface of a SOI substrate is divided into a plurality of sections, then the SOI film thickness is measured for each section Wi (i=1-n) by means of the spectral interference method using an optical fiber cable, and, simultaneously, the SOI film is etched down to a prescribed thickness by a dry etching device, and thus a desired value and a variance (.+-.0.3 micrometers) of the SOI film thickness is obtained.