Study In The Behavior Of Implanted Ions In Oxide Crystals

Since seventies of the 20^th century, people began to study irradiation damages in α-Al₂O₃ crystal due to the demands of development in space technology, many color centre in the damage of oxide crystals by ion implantation has been studied. Among them, F and F4 centre are most understood. Study in color centers of α-Al₂O₃ crystal by using ion implantation, usually, with different elemental metallic ions, however, study in them has not get been reported with compound ions. In our work, ion implantation in α-Al₂O₃ crystal was with a kind of molecular ions of compound CuCl⁺. The behaviors of color centers in α-Al₂O₃ crystal produced by CuCl⁺ ion implantation are reported in this paper, and surface morphologies of CuCl⁺ implanted α-Al₂O₃ after annealing with SEM observation were also reported in this paper.Several conclusions can be drawn as follows:1. Optical absorption and luminescence measurements have been done for the α-Al₂O₃ specimens implanted with CuCl⁺ ions. It is found that a strong absorption at UV section can be seen in optical absorption spectra for all of the specimens with different crystal orientations. The calculation of Gaussian fitting and measurements in luminescence confirm that there are several point defects such as F, F₂, F₂⁺, and F₂⁺2 centre in the CuCl⁺ -implanted α-Al₂O₃ samples.2. The; optical absorption intensities of the CuCl* implanted o-AlA â–  specimens are decreased by annealing treatment, this manifests that, thenumber of the color centers is decreased due to annealing. It is also found that decreases in number for different kinds of color centers are dependent greatly on implantation conditions, substrate orientation and annealing temperature.3. Sub-micrometer particles after annealing have been observed in the surface of the CuCl' implanted a Ml)-, specimens by us-ing SEM technique. The size of particles is greatly dependent on implantation conditions, substrate orientation and annealing temperature. It is expected that particles with nano-meter size could be formed at the suitable annealing temperature.4. Comparing with the behaviors of el iminating color centre produced by ion impLantation in different oxide crystals through annealing. It seems more difficult to eliminate color centre in covalence oxide crystal than in ion oxide crystal.