Semiconducting properties of tellurium films prepared on glass substrate by a partially ionized vapor deposition (PIVD) technique were studied and compared with those of Te films formed by a conventional vacuum evaporation technique. It was found that the PIVD technique effectively increased the Hall mobility and decreased the carrier concentration of Te films. These improved films could be utilized as the semiconductor layer of a thin film transistor(TFT) with smaller pinch-off voltage. A Te TFT with 10 nm-thick paladium film as the gate electrode was fabricated and its sensitivity to hydrogen gas was examined.

Doping of transition metals to zinc oxide (ZnO) is of great interest for its functionalization as magnetic semiconductor and electrocatalyst. In this study, electrodeposition of metal organic framework (MOF) thin films, in which zinc and cobalt ions are bridged by terephthalic acid (TPA), was made possible by adding TPA to an O2-saturated aqueous solution containing ZnCl2 and CoCl2. The resulting Zn-Co-TPA MOF was converted to a Co-doped ZnO thin film by annealing at 450 °C to burn away TPA and promote crystallization. Simple mixture of ZnCl2 and CoCl2 without TPA resulted in electrodeposition of Co2Cl(OH)3 along with ZnO, proving usefulness of TPA to blend Zn2+ and Co2+ ions having largely different solubilities and reduction potentials. The maximum achievable doping concentration was about 8%, because excessive addition of CoCl2 resulted in electrodeposition of metallic Co.

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