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:
Feb. 12, 2008
Filed:
Oct. 31, 2003
Susumu Maeda, Hiratsuka, JP;
Hiroshi Inagaki, Hiratsuka, JP;
Shigeki Kawashima, Hiratsuka, JP;
Shoei Kurosaka, Hiratsuka, JP;
Kozo Nakamura, Hiratsuka, JP;
Susumu Maeda, Hiratsuka, JP;
Hiroshi Inagaki, Hiratsuka, JP;
Shigeki Kawashima, Hiratsuka, JP;
Shoei Kurosaka, Hiratsuka, JP;
Kozo Nakamura, Hiratsuka, JP;
Komatsu Denshi Kinzoku Kabushiki Kaisha, Kangawa, JP;
Abstract
The present invention is to produce a silicon crystal wherein the boron concentration in the silicon crystal and the growth condition V/G are controlled so that the boron concentration in the silicon crystal is no less than 1×10atoms/cmand the growth condition V/G falls within the epitaxial defect-free region αwhose lower limit line LNis the line indicating that the growth rate V gradually drops as the boron concentration increases. A silicon wafer is also produced wherein the boron concentration in the silicon crystal and the growth condition V/G are controlled so as to include at least the epitaxial defect region β, and both the heat treatment condition and the oxygen concentration of the silicon crystal are controlled so that no OSF nuclei grow to OSFs.