Ba and/or Sr titanate films by organic chemical vapor deposition
US5786025A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 1996 |
| Grant date | Jul 28, 1998 |
| Priority date | — |
| Expiry date | Sep 9, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/409
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
High-purity MTiO.sub.3 (M=Sr and/or Ba)-type dielectric thin films with improved electric characteristics, particularly leakage currents and dielectric breakdown voltages, are prepared by MOCVD. Either or both a high-purity bis (.beta.-diketonato) Sr and Ba complexes, which each contain 1 ppm or less of each alkali metal and an alkaline earth metal as impurity metals, are used as the metal M supply sources. The high-purity volatile complexes are prepared by heat decomposition Sr or Ba nitrate (or acetate), which has been purified by a combination of recrystallization and ion-exchange chromatography, to contain 1 ppm or less of each alkali metal and alkaline earth metal as impurity metals, to thereby prepare high-purity SrO or BaO. The SrO or BaO is then reduced to high-purity metallic Sr or Ba by the thermit process, and then the metallic Sr or Ba is reacted with a .beta.-diketone to form the bis(.beta.-diketonato) complexes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.