One or more aspects of the present invention pertain to determining a relative orientation between an ion beam and lattice structure of a workpiece into which ions are to be selectively implanted by the ion beam, and calibrating an ion implantation system in view of the relative orientation. The beam to lattice structure orientation is determined, at least in part, by directing a divergent ion beam at the workpiece and finding the angle of the aspect of the divergent beam that implants ions substantially parallel to crystal planes of the workpiece, and thus causes a small amount of damage to the lattice structure.