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 resonance ionization detection. The Al atoms, which originate entirely from the top atomic layer of Ni₃Al(100), are predominantly sputtered along close packed <110> directions. On the other hand the sputtered Ni flux, which arises from both the first and second layers, has a large component normal to the surface. Molecular dynamics computer simulations agree well with experimental results and suggest that the normal emission of Ni atoms arises primarily from second-layer atoms.