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:
Aug. 03, 2010
Filed:
Feb. 18, 2005
Hiroshi Inagaki, Nagasaki, JP;
Masanori Honma, Nagasaki, JP;
Shigeki Kawashima, Nagasaki, JP;
Masahiro Shibata, Nagasaki, JP;
Hiroshi Inagaki, Nagasaki, JP;
Masanori Honma, Nagasaki, JP;
Shigeki Kawashima, Nagasaki, JP;
Masahiro Shibata, Nagasaki, JP;
Sumco Techxiv Corporation, Nagasaki, JP;
Abstract
A method for manufacturing a single crystal semiconductor, in which, in a process of pulling up the single crystal semiconductor from melt for growing it, an impurity is incorporated more uniformly into the single crystal semiconductor so that a variation in impurity concentration across the semiconductor wafer surface can be reduced, and thus, the planarity of the wafer can be improved. In the process of pulling-up the single crystal semiconductor (), fluctuation in a pulling-up speed is controlled, whereby the variation in concentration of the impurity in the single crystal semiconductor () is reduced. Especially, a width of speed fluctuation (ΔV) in 10 seconds is adjusted to less than 0.025 mm/min. Furthermore, in carrying out the control for adjusting the pulling-up speed such that a diameter of the single crystal semiconductor () becomes a desired diameter, a magnetic field having strength of 1,500 gauss or more is applied to the melt ().