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:
Jun. 19, 1990
Filed:
Oct. 06, 1988
Yoshihiro Morimoto, Kadoma, JP;
Kiyoshi Yoneda, Hirakata, JP;
Shoji Sudo, Nagaokakyo, JP;
Shoichiro Matsumoto, Hirakata, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
The invention relates to a method of growing a single crystal CaF.sub.2 film on a single crystal Si substrate having a principal plane of (100). According to the invention, the substrate temperature is first set at 550.degree.-600.degree. C. to grow a first CaF.sub.2 film (first stage) and the substrate temperature is then raised to 750.degree. C. or higher to grow a second CaF.sub.2 film on the first CaF.sub.2 film (second stage), thus the growth of the CaF.sub.2 films is performed separately in two stages. Since, in the second stage, the growth of CaF.sub.2 film is possible even at higher substrate temperature, the method of growing according to the invention makes it possible to grow a single crystal CaF.sub.2 film with flat surface morphology and excellent crystal quality.