Transparent Thin Film Transistors Based on InZnO for Flexible Electronics

There is strong interest in new forms of transparent, flexible or wearable electronics using non-Si materials deposited at low temperature on cheap substrates. While Si-based thin film transistors (TFTs) are widely used in displays, there are some drawbacks such as light sensitivity and light degradation and low field effect mobility (<1 cm2/Vs). For example, virtually all liquid crystal displays (LCDs) use TFTs imbedded in the panel itself. One of the promising alternatives to use of Si TFTs involves amorphous or nanocrystalline n-type oxide semiconductors. For example, there have been promising results with zinc oxide, indium gallium oxide and zinc tin oxide channels. In this paper, recent progress in these new materials for TFTs is reviewed. It is expected that GaInZnO transistor arrays will be used for driving laminar electroluminescent, organic lightemitting diode (OLED) and LCD displays. These transistors may potentially operate at up to an order of magnitude faster than Si FTFs.