Abstract
The in-situ resistivity measurement of partial crystalline amorphous ITO films was performed on annealing in various flowing gas atmospheres (air, O2, H2). It was found that an abnormal increase of resistivity showing a sharp peak was observed at 250∼300°C regardless of annealing gas atmospheres. The temperatures at the peak were shifted to higher range in the order of H2, air and O2 gases. The Hall measurement revealed that the carrier density and Hall mobility both sharply decrease at the resistivity peaks. The activation energy of the abnormal resistivity change was measured to be 0.6∼0.9 eV by using the Kissinger's method, whose values are different depending on the annealing atmospheres. The X-ray diffraction profiles and TEM observations revealed that the crystallization took place at ∼150°C on a whole specimen area and their crystal grains continuously grew with further increase of annealing temperature. It was tentatively concluded that the realignment of Sn-O bond to generate a neutral (2SnIn+Oi2-)x complex was most likely responsible for the present abnormal resistivity change observed.
