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:
Nov. 24, 1998
Filed:
Aug. 23, 1996
Kunihiro Sakamoto, Tsukuba, JP;
Atsushi Ando, Tsukuba, JP;
Agency of Industrial Science & Technology, Tokyo, JP;
Abstract
A method for surface flattening a crystal substrate includes (a) processing a surface of a silicon single crystal substrate, the surface deviating by 0.1.degree. or less from the (001) plane, so as to form a processed zone thereon which is an obstacle to the movement of surface steps present on the surface of the silicon single crystal substrate and which is adjacent to a preselected region having a surface to be flattened when viewed on an atomic level; (b) holding the substrate processed in step (a) in a chamber having an adjustable degree of vacuum so that the substrate has a temperature which is controlled by direct-current passage and heating; and (c) heating the substrate to move the surface steps along the substrate from the preselected region and gather the surface steps in the processed zone, thereby forming a flat surface in the preselected region of the substrate when viewed on the atomic level. In one embodiment, the direction of direct-current passage is displaced from the �1 1 0! and �1 1 0! directions, whereby the surface of the preselected region is flattened in all directions of the substrate surface.