Ferroelectric aerogel composites for voltage-variable dielectric tuning, and method for making the same
US5443746A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1994 |
| Grant date | Aug 22, 1995 |
| Priority date | — |
| Expiry date | Feb 14, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/624
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Ferroelectric composites are prepared by sol-gel derived procedures. The present invention utilizes the sol-gel process (1) to form a gel in a mold of the desired size and shape, (2) to dry the gel using a supercritical fluid extraction, (3) to sinter the dried gel to a crystalline ceramic, and finally (4) to impregnate the pores with a low loss polymer. The aerogel composition may be a barium titanate-based composition such as barium strontium titanate (BST). Making a ferroelectric aerogel composite provides a unique and novel means of fully exploiting the voltage- and/or frequency-tunable properties of certain compositions by maximizing their desirable properties and minimizing their undesirable characteristics such as loss at operational frequencies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.