Comparative study of proton and helium elastic scatterings from nitrogen in GaN

Abstract

Nitrogen determination is important in a variety of applications to characterize nitride-based compounds, or to study materials where nitrogen is unwanted. Analyzing such constituents in some materials with sufficient accuracy is always a challenge, although non-Rutherford (elastic) scattering is an applicable way to do such analysis. With this ion beam analysis technique various competing resonances are available for accurate determination of nitrogen. These involve protons and alpha particles based elastic scatterings. Here, GaN grown on sapphire is used as a base material with known concertation of nitrogen (50%) that can be used to understand the dynamics of such elastic scattering experiments. Elastic backscattering from 14N(p,p)14N and 14N(α,α)14N resonances are compared and it is observed that proton based resonances are more reliable than the alpha particle resonances to find and locate nitrogen in certain matrix, mainly due to the higher availability of discrete and well separated resonances of protons compared to the alpha particles in the energy range of a few MeV.