Title :
Sputter coated nanocrystalline ZnO for fabrication of thin film transistors
Author :
Kopparthi, Nikilesh ; Gautam, Madhav ; Jayatissa, Ahalapitiya H.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Univ. of Toledo, Toledo, OH, USA
Abstract :
Fabrication of zinc oxide based thin-film transistors (ZnO-TFT), by RF magnetron sputtering at room temperature has been realized on thermally oxidized silicon wafer followed by the metal evaporation and lift-off process. The configuration of the TFT was bottom gate with the gold contacts on P-doped silicon. The device was observed to be a “normally on” device. Electrical characteristics, mainly, channel mobility, on/off ratio, and threshold voltage were extracted from the electrical characterization of TFT. The ZnO-TFT was found to operate with a threshold voltage of 12.075 V, channel mobility of 110.44 cm2/Vs, and an on/off ratio of approximately 105. Thickness of the ZnO film was confirmed by the UV spectrometer. No photo effect was observed, making it an ideal material for flat-panel displays. X-ray diffraction was performed to find out the orientation of the ZnO layer on the substrates. Preferred orientation was in the 002 plane. The high mobilities, ease of fabrication and cost-effectiveness make the ZnO-TFT a very desirable electronic device for futuristic flexible electronics.
Keywords :
II-VI semiconductors; X-ray diffraction; electron mobility; elemental semiconductors; gold; nanofabrication; nanostructured materials; phosphorus; semiconductor growth; silicon; sputter deposition; texture; thin film transistors; ultraviolet spectra; vacuum deposition; wide band gap semiconductors; zinc compounds; P-doped silicon; RF magnetron sputtering; Si; Si:P-Au; SiO2-Si; TFT; UV spectrometry; X-ray diffraction; ZnO; bottom gate; channel mobility; electrical characteristics; flat-panel displays; gold contacts; lift-off process; metal evaporation; on-off ratio; preferred orientation; sputter coating; temperature 293 K to 298 K; thermally oxidized silicon wafer; thin film transistors; threshold voltage; Electron mobility; Fabrication; Logic gates; Materials; Sputtering; Thin film transistors; Zinc oxide; Lithography; Oxide; RF Sputtering; Thin-film Transistors;
Conference_Titel :
Electro/Information Technology (EIT), 2011 IEEE International Conference on
Conference_Location :
Mankato, MN
Print_ISBN :
978-1-61284-465-7
DOI :
10.1109/EIT.2011.5978589
