A thin film transistor (TFT) is special kind of field effect transistor made by depositing thin films for the metallic contacts, semiconductor active layer, and dielectric layer.

Most TFTs are not transparent themselves, but their electrodes and interconnects can be. The first transparent TFTs, based on zinc oxide were reported in 2003 by the researchers of the Oregon State University.

The best known application of thin-film transistors is in TFT LCDs, a variant of LCD technology. 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.

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