ZnO thin-film varistors and method of making the same
US5699035A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 1995 |
| Grant date | Dec 16, 1997 |
| Priority date | — |
| Expiry date | Mar 22, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/682
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A thin-film zinc oxide varistor (10) for use in integrated circuits and the like is produced by applying a polyoxyalkylated metal complex, such as a metal alkoxycarboxylate, to a substrate (12, 14, and 16) for the formation of a dried nonohmic layer (18). The method of production includes the steps of providing a substrate and a precursor solution including a polyoxyalkylated zinc complex (P22, P24), coating a portion of the substrate with the precursor solution (P26), drying the coated substrate (P32), and crystallizing the dried thin-film zinc oxide layer (P30). The resultant crystalline zinc oxide varistor layer (18) may be doped with bismuth, yttrium, praseodymium, cobalt, antimony, manganese, silicon, chromium, titanium, potassium, dysprosium, cesium, cerium, and iron to provide a non-ohmic varistor. The varistor layer (10) is annealed at a temperature ranging from about 400 to about 1000.degree. C. to provide a layer having a thickness ranging from about 50 nanometers to about 500 nanometers and an average grain size diameter less than about 200 nanometers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.