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:
Oct. 09, 2001
Filed:
Jun. 26, 2000
Hideki Naruoka, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An SOI substrate having a silicon layer formed on an embedded oxide layer is prepared at a step ST,. An exposed surface of the silicon layer is thermally oxidized for forming a thermal oxide film at a step ST,. The thermal oxide film, enclosing a defect in the silicon layer, is formed in a shape on or to which the defect is reflected or transferred. At this time, thermal oxidation is so executed that the transferred part of the thermal oxide film is in contact with the embedded oxide layer. The SOI substrate is dipped in a hydrofluoric acid solution at a step ST,. Thus, the thermal oxide film is removed while the embedded oxide layer is eroded through the part in contact with the thermal oxide film. According to this inspection method ST,, the defect is reliably transferred to the embedded oxide layer through the thermal oxidation step ST,, whereby it is possible to evaluate an inner defect undetectable/unevaluative by a conventional inspection method. Thus, the defect of the silicon layer is inspected/evaluated for obtaining an SOI substrate of high quality and improving the manufacturing yield of a semiconductor device.