Thin-film transistor
From Wikipedia, the free encyclopedia
A thin film transistor (TFT) is a special kind of field effect transistor made by depositing thin films for the metallic contacts, semiconductor active layer, and dielectric layer. The channel region of a TFT is a thin film that is deposited onto a substrate (often glass, since the primary application of TFTs is in liquid crystal displays).
Most TFTs are not transparent themselves, but their electrodes and interconnects can be. The first solution processed transparent TFTs (TTFTs), based on zinc oxide were reported in 2003 by researchers at Oregon State University.
The best known application of thin-film transistors is in TFT LCDs, a variant of LCD technology, especially for use in cellular phone display. Transistors are embedded within the panel itself, reducing crosstalk between pixels and improving image stability. As of 2004, all but the cheapest color LCD screens use this technology. TFT panels are heavily used in digital radiography applications including Mammography and General Radiography.
The new AMOLED (Active-Matrix OLED) screens also contain a TFT layer.
