AVS 57th International Symposium & Exhibition
    Electronic Materials and Processing Tuesday Sessions
       Session EM-TuP

Paper EM-TuP9
Fringing Field effects of Different Size Indium Gallium Zinc Oxide (IGZO) Active Layers Thin Film Transistors

Tuesday, October 19, 2010, 6:00 pm, Room Southwest Exhibit Hall

Session: Electronic Materials and Processing Poster Session
Presenter: J. Noh, University of Tennessee
Authors: J. Noh, University of Tennessee
S. Kwon, University of Tennessee
J.H. Noh, University of Tennessee
P.D. Rack, University of Tennessee at Knoxville; Oak Ridge National Laboratory
Correspondent: Click to Email
To realize the high performance-thin film transistors (TFTs) using amorphous indium gallium zinc oxide (a-IGZO) as the semiconducting active layer, we will present the how the a-IGZO with different active sizes affects the electrical characteristics of TFTs. The TFTs are fabricated with a bottom-gate staggered structure and the a-IGZO active size is photolithgraphically patterned to different lateral dimensions. A Cr gate is deposited on buffered silicon dioxide on a silicon substrate and SiNx is thegate dielectric which is deposited via plasma enhanced chemical vapor deposition (PECVD). The a-IGZO semiconducting active layers are deposited using rf magnetron sputtering in a reactive Ar-O2 atmosphere which controls the carrier concentration which can be metallic at low oxygen flow rates and insulating at high (>20% O2) flow rates. The a-IGZO layer is patterned with different size by wet etch process with diluted HF. Finally, source and drain electrodes are formed and the device is annealed for activation. We will discuss the TFT characteristics based on fringing electric field effects in which the fringing electric field around the periphery of the patterned source and drain electrodes can induce electrical conduction as current paths in the semiconductor layer, changing electrical properties in the device, especially increasing the leakage current through the backchannel on IGZO. Furthermore, we will correlate the different pattern size of IGZO to the electrical properties of the TFT devices . Finally, we will present a new application for our a-IGZO TFTs: an addressable microfluidic electrowetting channel device.