Device sensitivity of field-plated polysilicon high-voltage TFTs and their application to low-voltage operation

The device sensitivity to the offset length variations in the recently proposed field-plated (FP) polysilicon high-voltage thin-film transistor (HVTFT) has been studied. The device characteristics of the new FP-HVTFTs are found to be much more immune to misalignment errors; this is a very desirable feature, especially for large-area applications. FP-HVTFTs also exhibit lower leakage current than their conventional counterparts for up to 100-V operation. At typical low-voltage operation (e.g. 20 V), an improvement of about three orders of magnitude in the on/off current ratio can be readily achieved. These features, together with the simpler processing and improved turn-on characteristics reported earlier, make the FP-TFT a very promising device architecture for large-area microelectronics.<<ETX>>