Thermal Stability Of A Hfo2/Sio2 Interface

Using high-angle annular-dark-field scanning transmission electron microscopy, we showed how annealing at 1000 degrees C changes the chemical composition distribution at a HfO2/SiO2 interface. The observed change in the distribution was analyzed in terms of Hf diffusion in SiO2; the diffusion coefficient was estimated to be 2.5x10(-18) cm(2)/s. This diffusion coefficient indicates that the high-temperature annealing, such as that in the conventional dopant activation process used to fabricate semiconductor devices, barely changes the chemical composition distribution at the HfO2/SiO2 interface. (c) 2006 American Institute of Physics.