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. 09, 1998
Filed:
Feb. 13, 1996
Jun-ichi Matsubara, Tokyo, JP;
Yuji Miyake, Tokyo, JP;
Hiroshi Kongoji, Tokyo, JP;
Kouji Maeda, Tokyo, JP;
Mitsubishi Materials Silicon, Tokyo, JP;
Mitsubishi Materials Corporation, Tokyo, JP;
Abstract
A silicon single-crystal ingot which is nearly uniform in quality over the entire length of the column portion can be obtained to produce high-quality single-crystal silicon with high product yield and has the bottom column portion having the property close to the properties of the top column portion and the middle column portion. The bottom portion does not vary in shape among product lots and can be reproduced in the same shape. The diameter D2 of the bottom portion 2 is controlled in such a manner that the outer surface of the bottom portion 2a on the column portion side has an inclination angle .theta. of 10 to 25 degrees with respect to the outer surface of the column portion 1 and extends to the outer surface of the column portion.