THE EFFECT OF DYNAMICALLY UNSTABLE CHANNELING ON OFF-AXIS ION IMPLANTATION

Theoretical consideration and extensive numerical simulations are made to investigate directional effects at the implantation of heavy ions into single crystal targets. A novel molecular dynamics code MICKSER is developed for the simulations. The main goal is to solve the problem of suppression of the long-range channeling tails at off-axis implantation. It is revealed for the first time that a part of the above-barrier ions possess the specific mode of dynamically unstable directed motion, the metachanneling. It is a transient mode between the stable channeling and quasichanneling providing a reduced stopping of ions and affecting the as-implanted doping profiles. The analytical model resulted in new critical transverse energy. The critical angle of metachanneling has been proposed. They determine the upper bound of the energy losses channeling dip at low-energy ion implantation. It has been demonstrated that the minimization of channeling tails can be practically achieved when tilting a target by the critical angle of metachanneling.