Mass-Spectrometric Study of Sputtering of Single Crystals of GaAs by Low-Energy A Ions

Abstract

Single crystals of GaAs [(110), (111), and (1̄1̄1̄) faces] were sputtered by normally incident low-energy (0–140 eV) argon ions in the source of a mass spectrometer. For each face, approximately 99.4% of the collected ions were neutral Ga and As atomic species; the balance were neutral GaAs molecules. No neutral Ga2, As2 or (GaAs)2 molecules, or negative Ga−, As−, or (GaAs)− ions, with the characteristics of sputtered particles, were detected. Sputtering ``yields'' for the three faces were found to be: ``Y'' (111) ≈ ``Y'' (1̄1̄1̄) > ``Y'' (110).