We report on the fabrication and performance of amorphous oxide thin-film transistors with In-Ga-Zn-O deposited by
RF magnetron reactive sputtering for semiconductor channel layer. The influence of the electrical transport properties of
the channel on the electrical parameters of thin-film transistors has been determined. By optimizing process parameters
depletion-mode n-channel devices with maximum field-effect mobility (μFE) 10.1 cm2/Vs, threshold voltage Vth=-4.85V
and on to off current ratio (Ion/Ioff)=2.1x102 have been demonstrated.
In-Ga-Zn-O thin films fabricated by reactive RF magnetron sputtering have been investigated for their compositional,
structural, morphological, electrical and optical properties. All resulting films present the amorphous microstructure, and
root mean square roughness below 0.6 nm. The variation of the oxygen content in the deposition atmosphere from 0% to
0.9% results in the formation of a-IGZO thin films consisting of 15-29% indium, 16-28% gallium, 10-13% zinc and
30-60% oxygen, which significantly differs from the InGaZnO4 target composition. IGZO thin films present
the transmittance in range of 75% to 90% for VIS-NIR wavelengths. Mechanism of free electrons generation via oxygen
vacancies formation is proposed to determine the relation between oxygen content in the deposition atmosphere and
the transport properties of the IGZO of the thin films.