Display device with an improved contact hole arrangement for contacting a semiconductor layer through an insulation film
US6936847B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2003 |
| Grant date | Aug 30, 2005 |
| Priority date | — |
| Expiry date | Apr 17, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/13454
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Thin film transistors for a display device each include a semiconductor layer made of polysilicon having a channel region, drain and source regions at both sides of the channel region and doped with impurity of high concentration, and an LDD region arranged either between the drain region and the channel region or between the source region and the channel region and doped with impurity of low concentration. An insulation film is formed over an upper surface of the semiconductor layer and has a film thickness which decreases in a step-like manner as it extends to the channel region, the LDD region, the drain and the source regions; and a gate electrode is formed over the channel region through the insulation film. Such a constitution can enhance the numerical aperture and can suppress the magnitude of stepped portions in a periphery of the thin film transistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.