Process for manufacturing an alumina substrate by acid purifying a prefired substrate before final firing
US4217337A · kind A · utility
7Cited by
3References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 30, 1978 |
| Grant date | Aug 12, 1980 |
| Priority date | — |
| Expiry date | Oct 30, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B41/91
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Disclosed is an alumina substrate having a high density, a high degree of surface smoothness and excellent dielectric properties and a process for its manufacture. The process comprises prefiring a green sheet prepared from alumina powder at an elevated temperature, for example between 1200.degree. and 1350.degree. C., to remove combustible substances from the sheet, treating the resultant prefired substrate with an acid aqueous solution to eliminate acid-soluble and decomposable substances from the substrate, and firing the acid-treated substrate at an elevated temperature, for example between 1500.degree. and 1650.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.