A transparent thin film transistor of yttrium-doped CuSCN has been devised with a remarkable hole mobility of 0.99 cm2 V−1 s−1.

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This work reports development of yttrium doped copper oxide (YÀ CuO) as a new hole transport material with supplemented optoelectronic character. The pure and Y-doped CuO thin films are developed through a solid-state method at 200°C and recognized as high performance p-channel inorganic thin-film transistors (TFTs). CuO is formed by oxidative decomposition of copper acetylacetonate, yielding 100 nm thick and conductive (40.9 S cm À 1 ) compact films with a band gap of 2.47 eV and charge carrier density of~1.44 × 10 19 cm À 3 . Yttrium doping generates denser films, Cu 2 Y 2 O 5 phase in the lattice, with a wide band gap of 2.63 eV. The electrical conductivity increases nine-fold on 2 % Y addition to CuO, and the carrier density increases to 2.97 × 10 21 cm À 3 , the highest reported so far. The TFT devices perform remarkably with high field-effect mobility (μ sat ) of 3.45 cm 2 V À 1 s À 1 and 5.3 cm 2 V À 1 s À 1 , and considerably high current-on/off ratios of 0.11 × 10 4 and 9.21 × 10 4 , for CuO and YÀ CuO films, respectively (at À 1 V operating voltage). A very small width hysteresis, 0.01 V for CuO and 1.92 V for 1 % YÀ CuO, depict good bias stability. Both the devices work in enhancement mode with stable output characteristics for multiple forward sweeps (5 to À 60 V) at À 1V g .