Rutherford Backscattering Spectroscopy

Abstract

Rutherford backscattering spectroscopy (RBS) is one of the most powerful techniques for measuring elemental depth profiles. It allows quantitative and nondestructive analysis with a reasonable depth resolution. In conventional RBS (combination of 1–4 MeV He ions with a silicon surface‐barrier detector), the typical depth resolution is about 10 nm and the typical mass resolution is about 1 u for light elements (mass number M < 20) and about 20 u for heavy elements ( M ca. 200). Sensitivity of 100 ppm can be easily obtained for heavy elements in light hosts although analysis of light elements in heavy hosts is difficult. In the present article, physical concepts which RBS relies on are briefly introduced. Some examples of analyses are demonstrated and several advanced techniques which have been developed to improve capabilities of the conventional RBS are discussed.