Method of growing CaF.sub.2 film
US4935092A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 1988 |
| Grant date | Jun 19, 1990 |
| Priority date | — |
| Expiry date | Oct 6, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S117/902
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.