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.

Date of Patent:
Apr. 23, 2013

Filed:

Aug. 27, 2010
Applicants:

Maria Claudia Custodio Kajiyama, San Jose, CA (US);

Dieter Hans Jundt, Palo Alto, CA (US);

Stephane Chamaly, Singapore, SG;

Inventors:

Maria Claudia Custodio Kajiyama, San Jose, CA (US);

Dieter Hans Jundt, Palo Alto, CA (US);

Stephane Chamaly, Singapore, SG;

Assignee:

Crystal Technology, Inc., Palo Alto, CA (US);

Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01G 33/00 (2006.01); C01D 15/00 (2006.01);
U.S. Cl.
CPC ...
Abstract

The low Ta impurity content in pyrochlore ore makes it unnecessary to use a solvent extraction process to separate Nb from Ta. Consequently, niobium pentoxide powders using this ore can be produced at lower cost than competing mining/refining approaches, but in turn contain significant amounts of Ta impurities. SAW wafers are grown from melts produced by reacting niobium pentoxide powders containing Ta impurities at levels of 200 ppm or more by weight. Given proper amounts of starting powders, crystals can be grown with good yields and reproducible properties that satisfy typical SAW wafer specifications. The consistency across various lots of powders may be further improved by adding an appropriate amount of Ta pentoxide to the starting powders.


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