  Amorphous metal oxide thin-film transistors (TFT) are fabricated using
InOx-based semiconductors doped with TiO2, WO3 or SiO2. Although density of
dopant is low in the film, change in the electrical properties showed strong
dependence on the dopant species. We found that the dependence could be
reasonably explained by the bond-dissociation energy. By incorporating the
dopant with higher bond-dissociation energy, the film becomes less sensitive to
oxygen partial pressure used during sputtering deposition and remains
electrically stable to thermal annealing treatment. The concept of
bond-dissociation energy can contribute to the realization of more stable metal
oxide TFTs for flat panel displays.
