Structure of thin film transistors
US4404578A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 1980 |
| Grant date | Sep 13, 1983 |
| Priority date | — |
| Expiry date | Jul 30, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D62/235
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A thin film transistor comprises a substrate, a gate electrode, a drain electrode, a source electrode, an insulative layer, and a semiconductor layer for the purpose of switching display signals to be applied to at least one display element of a display device. Preferably, the thin film transistor is mounted on the same substrate on which the display element is mounted. The selected material for the display element electrode is identical to at least one selected from the gate electrode, the source electrode, and the drain electrode. In another aspect of the present invention neither the gate electrode nor the insulating layer overlap either of the drain electrode or the source electrode. A resistance value of the semiconductor layer between the source and the drain electrodes is considerably less than the resistance value of the semiconductor channel layer controlled by the gate electrode. For this purpose, at least one of the width, thickness, and impurity concentration is varied therebetween. In a further aspect, the semiconductor channel has a substantial length more than the distance between the source electrode and the drain electrode with the help of a labyrinth passage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.