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:
Apr. 03, 2018
Filed:
Jan. 15, 2014
Massachusetts Institute of Technology, Cambridge, MA (US);
Emanuel M Sachs, Newton, MA (US);
James G. Serdy, Boston, MA (US);
Eerik T. Hantsoo, Atlanta, GA (US);
MASSACHUSETTS INSTITUTE OF TECHNOLOGY, Cambridge, MA (US);
Abstract
An original wafer, typically silicon, has the form of a desired end PV wafer. The original may be made by rapid solidification or CVD. It has small grains. It is encapsulated in a clean thin film, which contains and protects the silicon when recrystallized to create a larger grain structure. The capsule can be made by heating a wafer in the presence of oxygen, or steam, resulting in silicon dioxide on the outer surface, typically 1-2 microns. At least one support element supports the wafer at the time the capsule is provided and blocks only minimal surface area from contact with the film forming atmosphere. There may be a plurality of support elements, or a surface may provide such support. The capsule contains the molten material during recrystallization, and protects against impurities. Recrystallization may be in air. After recrystallization, the capsule is removed.