Quantitative Surface Analysis Using Photoionization of Sputtered Neutrals

Abstract

Surface quantitative elemental composition information is a fundamental measurement of critical importance to the design and evaluation of materials and components. Secondary ion mass spectrometry (SIMS) and spectroscopic techniques based on secondary electron energy measurements, such as electron spectroscopy for chemical analysis (ESCA) and Auger spectroscopy, are well-established analytical tools used to meet such a requirement in the industry. SIMS is a highly sensitive technique, capable of detecting trace element at ppm level. However, based on detection of ionized materials ejected during sputtering, SIMS has difficulties in quantification at surfaces and interfaces due to its well-known matrix effect. On the other hand, ESCA and Auger spectroscopy have good quantification capability, but low sensitivity. The detection limit of ESCA or Auger spectroscopy is ≤ 0.1% of the total sample composition[1].