TRI3DYN – Collisional computer simulation of the dynamic evolution of 3-dimensional nanostructures under ion irradiation

A computer program is described which allows fully three-dimensional dynamic collisional simulations of ion irradiation effects in particular in nanosystems. The program is based on the well-known TRIDYN code which describes dynamic modifications along one dimension. In a computational volume composed of fixed and equisized voxels, local atomic density changes due to ion implantation or recoil relocation are relaxed to constant predefined atomic volumes. This is accomplished by interaction with neighboring voxels and by material transport from and to the surface. Arbitrary initial system shapes and elemental distribution can be defined as well as a wide range of irradiation conditions including non-uniform beam profiles. The paper addresses details of the involved algorithms, discusses potential artifacts with respect to surface sputtering, broadening of compositional profiles and surface contours. It demonstrates the capabilities of the program on the basis of examples for focused ion beam erosion, self-organized surface pattering, and ion implantation and sputter-shaping of nanostructures.