ANGLE AND ENERGY-DISTRIBUTIONS OF NEUTRAL ATOMS SPUTTERED FROM NI3AL(100)

The energy and angular distributions of Ni and Al atoms sputtered from Ni3Al(100) by 8 keV Ar+ have been measured using multiphoton resonanc e ionization detection, The Al atoms, which originate entirely from th e top atomic layer of Ni3Al(100), are predominantly sputtered along cl ose packed < 110 > directions. On the other hand the sputtered Ni flux , which arises from both the first and second layers, has a large comp onent normal to the surface. Molecular dynamics computer simulations a gree well with experimental results and suggest that the normal emissi on of Ni atoms arises primarily from second-layer atoms, (C) 1998 John Wiley & Sons, Ltd.