Thin film EL element and process for producing the same
US4857802A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 1987 |
| Grant date | Aug 15, 1989 |
| Priority date | — |
| Expiry date | Sep 24, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B33/22
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A thin film EL element which comprises an insulating substrate, a transparent electrode, a first insulating layer, a light-emitting layer, a second insulating layer and a back side electrode, successively laid one upon another, at least one of the first and second insulating layers being composed of a material having a perovskite crystal structure, for example, a layer of SrTiO.sub.3, PbTiO.sub.3 or BaTiO.sub.3, particularly a SrTiO.sub.3. The material having the perovskite crystal structure has an increased (111) plane orientation such that the diffraction intensity ratio of (111) plane to (110) plane, I (111)/I (110), is more than 0.5. The material can be a single crystal, having (111) plane orientation. The material is deposited by sputtering, at substrate temperatures of not less than 200.degree. C. and up to the softening point of the insulating substrate, and at a pressure of not more than 1.times.10.sup.-2 Torr. The material has a high dielectric constant, a high dielectric strength and thus has a high reliability of element performance with a low driving voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.