ATOMIC-FORCE MICROSCOPY INVESTIGATION OF ION-BOMBARDED INP - EFFECT OF ANGLE OF ION-BOMBARDMENT

Samples of InP(100) n-doped with S atoms to 4 x 10(18) cm(-3), were bo mbarded with 0.5 keV argon ions and with krypton ions of energy 0.5 an d 5 keV at various angles to the sample normal. The ion dose density f or 0.5 keV Ar+ and 0.5 keV Kr+ bombardment was 5 x 10(16) ions cm(-2), whereas for 5 keV Kr+ it was 2 x 10(16) ions cm(-2). The ion current density was set to a low value of 5 x 10(13) ions cm(-2) s(-1) to mini mize the sample heating. The resulting s topography development was in vestigated with an atomic force microscope, The surface roughness was quantified and analysed as a function of the angle of ion bombardment, Two- and three-dimensional images showing various types of topography and sputter cone size (height and width) are also presented, Close re semblance between the dependency of roughness and sputter rate on angl e of ion incidence suggests a correlation between the two.