Nonionizing energy loss (NIEL) for heavy ions

The concept of nonionizing energy loss (NIEL) has been found useful for cha racterizing displacement damage effects in materials and devices. Published tabulations, however, are limited with respect to target materials, partic le types and energies. In this paper we show how the NIEL database can be s ignificantly expanded to include heavy ions in the coulombic limit by using the Monte Carlo code SRIM. The methodology used to extract NIEL from SRIM is described This greatly adds to the number of materials and incident part icles for which the NIEL concept can be applied. To show that values so der ived are consistent with previous calculations, we compare alpha particle N IEL for GaAs derived from SRIM with a direct analytical calculation. The SR IM code is limited in that only coulombic interactions are considered. Gene ral rules of thumb are also described which permit prediction of NIEL for a ny target material over a large energy range. Tabulated values of NIEL for alpha particles incident on Si, GaAs and InP are presented.