Thin film transistor films made with anodized film and reverse-anodized etching technique
US5970326A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1997 |
| Grant date | Oct 19, 1999 |
| Priority date | — |
| Expiry date | May 21, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/1368
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Anodising treatments are used to form insulating films (12) in the manufacture of a flat-panel display or other large-area thin-film electronic device. A first film (1,101) of anodisable material (e.g Al) is anodised through a part of its thickness to form an anodic second film (2). A mask pattern (4), e.g of photoresist, is provided at least on the second film (2) to define an area (5) where the second film (2) is etched away through at least a part of its thickness and where a further anodising step is carried out to form an anodic third film (3) contiguous with a remaining part of the anodic second film (2). The manufacture is simplified by using reverse-anodising in an electrolyte solution (20) to carry out the etching of the second film (2). The first film (1,101) is biased negatively as a cathode to carry out the reverse-anodising, after which the further anodising step is carried out by biasing the first film (1,101) positively as an anode in the same electrolyte solution (20) to form the anodic third film (3). A remaining part (11a, 11b) of the first film (1) may provide a conductor track or gate electrode over which there is an insulating film (12) comprising a part of the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.