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:
Dec. 23, 2014
Filed:
Oct. 07, 2008
Harold J. Hovel, Katonah, NY (US);
Harold J. Hovel, Katonah, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An energy conversion device comprises at least two thin film photovoltaic cells fabricated separately and joined by wafer bonding. The cells are arranged in a hierarchical stack of decreasing order of their energy bandgap from top to bottom. Each of the thin film cells has a thickness in the range from about 0.5 μm to about 10 μm. The photovoltaic cell stack is mounted upon a thick substrate composed of a material selected from silicon, glass, quartz, silica, alumina, ceramic, metal, graphite, and plastic. Each of the interfaces between the cells comprises a structure selected from a tunnel junction, a heterojunction, a transparent conducting oxide, and an alloying metal grid; and the top surface and/or the lower surface of the energy conversion device may contain light-trapping means.