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:
Jul. 05, 2011
Filed:
Sep. 22, 2010
Applicant:
Tsun-neng Yang, Taipei, TW;
Inventor:
Tsun-Neng Yang, Taipei, TW;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 21/322 (2006.01);
U.S. Cl.
CPC ...
Abstract
Metal impurities of an upgraded metallurgical grade (UMG) silicon (Si) wafer are reduced. The UMG Si wafer having a 5N (99.999%) purity is chosen to grow a high-quality epitaxial Si thin film through atmospheric pressure chemical vapor deposition (APCVD). Through heat treating diffusion, the epitaxial Si film is used to form sink positions for the metal impurities in the UMG Si wafer. By using concentration gradient, temperature gradient and interface defect, individual and comprehensive effects are built for enhancing purity of the UMG Si wafer from 5N to 6N. Thus, a low-cost Si wafer can be fabricated for Si-based solar cell through a simple, fast and effective method.