High shear rolled alumina ceramic substrate
Abstract
Abstract A HIGH DENSITY HIGH SHEAR ALUMINA CERAMIC SUBSTRATE WHICH IS ESPECIALLY SUITABLE FOR USE AS A SUBSTRATE FOR THE DEPOSITION OF THIN METALLIC FILMS USED IN ELECTRONIC APPLICATIONS SAID SUBSTRATE HAVING A SURFACE SMOOTHNESS OF BETTER THAN 8 MICRO INCHES, WITHOUT THE USE OF A GLAZE COMBINED WITH A BULK TABULAR CRYSTALLINE ALUMINA DENSITY OF AT LEAST ABOUT 98 PERCENT OF THE THEORETICAL DENSITY OF A SURFACE DENSITY SUBSTANTIALLY THAT OF CRYSTALLINE ALUMINA AND A POROSITY OF SUBSTANTIALLY ZERO PROVIDED BY AN UNIQUE CRYSTALLINE SURFACE LAYER OF RANDOMLY ORIENTED CLOSE PACKED ALUMINA CRYSTALS OF HEXAGONAL PRISMATIC FORM ON SAID SUBSTRATE. THE SUBSTRATES, WHICH ARE PRODUCED FROM REACTIVE ALUMINA POWDER, HAVE HIGH FLEXURAL STRENGTH, EXCELLENT ELECTRICAL PROPERTIES AND ARE IMPERVIOUS TO PENETRATION BY METALS, DYES OR INKS.
Inventors
- 👤 K Kappes
- 👤 S Bateson
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-18 | 1976-12-18 | 1977-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-18 | 1980-12-18 | 1981-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-18 | 1984-12-18 | 1985-06-19 | $7700.00 | Window Closed / Lapsed |