Spatial Distribution of Energy Deposited by Energetic Heavy Ions in Semiconductors

Abstract

A new general principle is described which provides a simple and direct method for predicting the spatial distribution of energy absorbed in nuclear collisions, especially in atomic displacement processes, in heavy ion bombarded semiconductor materials. To calculate the energy transfer rate into atomic displacements, an energy distribution function of incident ions at an arbitrary penetration depth is derived and integrated together with a weight function made from the total cross section for the production of displaced atoms and the average energy transfer corresponding to those encounters which can displace atoms in the substrate materials. Numerical data obtained in each procedure of the method are presented and compared with the results revealed by many theoretical and experimental works attempted up to present. The average number of knock-on atoms produced by an incident ion and associated knock-ons is calculated in a unique manner. Problems of the vacancy distribution and the amorphization criterion are also discussed.