Depth Profiling of Light Elements using Neutron Induced Reactions

Abstract

Neutron depth profiling (NDP) is a non-destructive analytical technique used for the analysis of elemental depth distributions at the near surface of materials. Profiles are determined by measuring the energy loss of charged particles produced by (n, α) or (n, p) reactions. Technologically important light elements like B and Li are easily analyzed which are not often possible to accurately analyze by other methods. Since the use of cold neutron beams for NDP guided from nuclear reactors, the applications have expanded substantially including microelectronics. This paper reviews the fundamental principle and characteristics, analysis systems and method, as well as uses of NDP. As for applications of NDP, the paper focuses on modern applications reported since 1990s; such as diamond, diamond like carbon (DLC) and cubic-boron nitride (c-BN), electrochromic devices, lithium ion batteries, nuclear fusion reactor materials, and high level radioactive-waste processing related materials. Finally, the author suggests starting an NDP research program using low energy guided neutrons at JRR-3M in Japan.