Temperature dependence of the electrical characteristics of low-temperature processed zinc oxide thin film transistors

• Zinc oxide thin film transistors are characterized with temperature, T.
• For T < 330 K, transfer curves remain practically constant.
• For T > 330 K, transfer curves show negative shift and series resistance increases.
• The drain current, IDS, shows Arrhenius-type dependence in subthreshold regime.
• For drain smaller than gate bias, in above threshold regime, IDS reduces with T.

The impact on the electrical behavior of thin film transistors, TFTs, based on zinc oxide, ZnO-based TFTs, with temperature is analyzed. ZnO is deposited using pulsed laser deposition techniques and the temperature used during the entire fabrication process is kept below 100 °C. Up to 330 K, the transfer curves practically remain constant or slightly shifted toward more positive voltages. For temperatures up to 330 K, they show the combined effect of the threshold voltage shifting toward more negative voltages and the increase of series resistance. The drain current shows an Arrhenius-type dependence with temperature in subthreshold regime with activation energy of around 0.53 eV. In above threshold regime, for temperatures above 330 K, the activation energy is around 0.15 eV.