A Comparative Study of Solid Surface Analyses between Low Energy Ion Scattering Spectroscopy(ISS)and Secondary Ion Mass Spectroscopy(SIMS)

Abstract

Experimental studies of solid surface analyses are carried out by means of low energy ion scattering spectroscopy(ISS)and secondary ion mass spectroscopy(SIMS) . The instrument is composed of a HITACHI IMA-2 ion probe and a stigmatic second-order double focusing mass spectrometer(electric toroidal sector: r_e=212mm, Φ_e=85°, c=0.5; uniform magnetic sector: r_m=200mm, Φ_m=90°, ε₁=32°, ε₂=-10°). ISS analyses are carried out using the electric toroidal sector, while SIMS analyses employ both the electric and magnetic sectors. Primary 5 keV argon and helium ion beams are used for ISS analyses, and 8 keV oxygen ion beams for SIMS analyses. An aluminium plate, an Au-Ag-Cu alloy and a GaP crystal are analyzed. The obtained ISS and SIMS spectra are compared. The element discrimination characteristics of ISS are much more accurate than those of SIMS. Maximum mass resolving powers are obtained at30(50% valley separation)for ISS, and 11, 000(10% valley separation)for SIMS.