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. 18, 2001
Filed:
Dec. 13, 1999
David W. Weyburne, Maynard, MA (US);
Brian S. Ahern, Boxboro, MA (US);
The United States of America as represented by the Secretary of the Air Force, Washington, DC (US);
Abstract
This invention is a process and apparatus for producing single crystal, polycrystal or amorphous stand-alone films. The process has two steps: First, thin layers of the desired materials are deposited by VD onto a hot foreign single crystal substrate wafer held by a substrate platter in a pocket formed in such. The second step is to chemically etch away the substrate while still being held by the substrate platter while the film-substrate is still hot. The etch is stopped as soon as all of the foreign substrate is consumed. This leaves just the thin film which is then cooled down to room temperature. The bottom surface of this pocket has a plurality of channels for carrying an etching gas which is input by a central channel in the substrate platter. The reactants that form the stand-alone film are input through an actively cooled effusion cell having a plenum for receiving the reactant gas. The reactant gas flows past a plurality of parallel spaced-apart tubes having a coolant therein onto the heated substrate surface which is in very close proximity to the coolant tubes. The thin films can be deposited by any of the various VD methods such as plasma assisted CVD and D.C. or RF sputtering.