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:
May. 09, 2000
Filed:
Mar. 08, 1999
Mitsubishi Gas Chemical Company, Inc., Tokyo, JP;
Abstract
A method is used when manufacturing a bismuth-substituted rare-earth iron garnet single crystal (BIG) film by the LPE method. The BIG film is grown on one side of a non-magnetic garnet substrate using a melt that contains flux components and rare-earth oxides. An amount of calcium is added to the melt such that a difference between optical absorption coefficients of the film at a wavelength of 0.78 .mu.m before and after subjecting the film to hydrogen-reduction treatment ranges from 660 to 1430 dB/cm. The film is grown on a non-magnetic garnet substrate having a thickness in the range of 400-600 .mu.m, at a crystal growth temperature of the melt to form a film-substrate structure. The film-substrate structure has a curvature ranging from +0.3 to +0.7 m.sup.-1 at room temperature. The film-substrate structure is subjected to the hydrogen reduction at a temperature ranging from 320 to 400.degree. C. in a hydrogen atmosphere, so that the curvature of the film-substrate structure decreases to a value ranging from -0.1 to +0.1 m.sup.-1.