RBS-CHANNELING AND TEM STUDIES ON THE REGROWTH OF LOW-TEMPERATURE ARGON ION AMORPHIZED LITHIUM TANTALATE (LITAO3) SINGLE-CRYSTAL

The annealing behavior of a ferroelectric LiTaO3 single crystal amorph ized by irradiation of 218 keV Ar ions at liquid nitrogen temperature was studied using Rutherford Backscattering Spectrometry (RBS) with th e Channeling technique and Transmission Electron Microscopy (TEM). It was observed that the regrowth rate of the amorphous layer irradiated to a dose of 6 x 10(16) cm(2) was much faster than that of the amorphi zed layer irradiated to a dose 6 x 10(14) cm(2). In the former case, r egrowth continued up to 675 degrees C and the total regrowth is about 73% of the original amorphous laver, while in the latter case, the reg rowth nearly stopped at 450 degrees C and further annealing up to 725 degrees C induced little regrowth. The total regrowth is only about 24 % of the original amorphous layer. It was also observed that the regro wth of the amorphous layer depends on the history of the heat-treatmen t. (C) 1998 Published by Elsevier Science B.V.