AVS 53rd International Symposium
    Electronic Materials and Processing Thursday Sessions
       Session EM-ThP

Paper EM-ThP4
UV-Detecting Top-Gate ZnO-TFTs with Polymer Dielectric for Optical Inverter Application

Thursday, November 16, 2006, 5:30 pm, Room 3rd Floor Lobby

Session: Electronic Materials and Processing Poster Session
Presenter: K.M. Lee, Yonsei University, Korea
Authors: K.M. Lee, Yonsei University, Korea
J.-M. Choi, Yonsei University, Korea
J.H. Park, Hongik University, Korea
E. Kim, Hongik University, Korea
C.S. Kim, Yonsei University, Korea
H.K. Baik, Yonsei University, Korea
S. Im, Yonsei University, Korea
Correspondent: Click to Email
Very recently ZnO thin-film transistors (TFTs) have attracted much interest from researchers and engineers because they have potentials to realize transparent electronics. However, most of the reported devices were based on bottom-gate structures. We have successfully fabricated ZnO-based TFTs of a top-gate structure with organic polymer dielectric and also realized optical inverters by using their UV-detecting properties. ZnO channel layers were patterned by rf magnetron sputtering on glass substrate, and then Al source/drain electrodes were deposited by thermal evaporation. PVP dielectric layers were subsequently deposited by spin casting. Finally, semi-transparent conducting NiOx gate windows were patterned on the PVP layers. In spite of the relatively lower mobilities (~0.01 cm@super 2@/Vs) than those of other bottom-gate ZnO TFTs with inorganic dielectric layers, our ZnO-TFT with polymer dielectric has a good UV responsity (at wavelength ~364 nm) as a photo-detector and showed a fast response for optical gating (including detecting and inverting actions). For these demonstrations of optical inverters, we set up an appropriate array of photo TFTs and load registers. Furthermore, we attempt to enhance the mobility and to lower the operating voltage of our top gate ZnO-TFTs by adopting a hybrid gate dielectric of high-k inorganic/organic (PVP) sandwich structure. More and advanced details will be discussed in the meeting.