Diffusivity of the interstitial hydrogen shallow donor in In2O3

Hydrogen has been found to be an n-type dopant in In2O3 that gives rise to unintentional conductivity. An infrared (IR) absorption line observed at 3306 cm(-1) has been assigned to the H(i)(+)center. Two types of experiments have been performed to determine the diffusivity of H-i(+) in In2O3 from its IR absorption spectra. (i) At temperatures near 700 K, the O-H line at 3306 cm(-1) has been used to determine the diffusivity of H-i(+) from its in-diffusion and out-diffusion behaviors. (ii) At temperatures near 160 K, stress has been used to produce a preferential alignment of the Hi thorn center that has been detected in IR absorption experiments made with polarized light. With the help of theory, the kinetics with which a stress-induced alignment can be produced yield the time constant for a single jump of the H(i)(+)center and also the diffusivity of H-i(+) near 160 K. The combination of the diffusivity of H-i(+) found near 700K by mass-transport measurements and that found near 160K from the time constant for a single H-i(+) jump determines the diffusivity for H-i(+) over eleven decades! Published by AIP Publishing.