TRILAYER, A-SIH THIN-FILM TRANSISTOR PREPARED FROM 2 PHOTOMASKS A SELF-ALIGNED

A new self-aligned TFT structure that requires two photomasks is described in this paper. Three process steps, i.e., the backlight lithography, the top dielectric etch, and the n+ etch, have been studied in detail. The finished TFT has transfer characteristics and Jd Vd curves similar to those of a TFT prepared from a more complicated conventional process. TFT structure parameters, such as the channel length, the a-Si:H thickness, the source/drain via size, and the contact resistance, affect the field effect mobility and the Ion /Ioff ratio. These relations were examined. Including a Ta2O5 thin layer in the gate dielectric structure changes the device characteristics. The relation between the Ta2O5 process and the device has been studied. 1991, The Electrochemical Society, Inc. All rights reserved.

A SELF-ALIGNED, TRILAYER, A-SIH THIN-FILM TRANSISTOR PREPARED FROM 2 PHOTOMASKS Academic Article