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:
Jun. 11, 1991
Filed:
Jul. 24, 1990
Akira Izumi, Kyoto, JP;
Keiji Toei, Kyoto, JP;
Nobuatsu Watanabe, Kyoto, JP;
Yong-Bo Chong, Kyoto, JP;
Dainippon Screen Mfg. Co., Ltd., Kyoto, JP;
Abstract
A method for removing a film on a silicon layer formed on a surface of a substrate includes the steps of: (a) placing a substrate in a reaction chamber to be isolated hermetically from the outside air, and (b) feeding anhydrous hydrogen fluoride and alcohol simultaneously into the reaction chamber. Preferably, the method further includes the step of feeding only alcohol into the reaction chamber prior to and/or subsequent to the step (b). An alcohol layer is formed on the substrate surface, whereby the film can be removed uniformly by anhydrous hydrogen fluoride. A by-product of the reaction is taken out from the system of reaction by means of the alcohol on the substrate. No by-product remains on the substrate after the reaction. Since the silicon layer after the reaction is covered with alcohol, re-growth of a native oxide film thereon is also suppressed and on ionic contamination such as fluorine remains on the substrate surface.