Mpnte Carlo Simulation of Silicon Amorphization During Ion Implantation

When a sufficient high dose of energetic ions is implanted into a silicon crystal, irradiated zones of the crystal are transformed to an amorphous state. The thickness and spatial location of the amorphous layers determine the type of the extended defects and the number of point defects remaining in the silicon crystal after a recrystallization step. I t is believed that the lateral diffusion of the defects is a possible source of the inverse short channel effect in MOS transistors. We present an accurate multi-dimensional model to predict the range of amorphous layers within ion implanted single-crystal silicon. The critical parameters ruling the amorphization process are the implantation dose D , the ion mass and energy, and the substrate temperature T which are all taken into account by our simulation method. The kinetic properties of amorphous silicon layers are well characterized [l] but the mechanisms of its formation by ion bombardment are still under investigation [2][3] and a quantitative description of this phenomenon within a TCAD environment was not available up to now.