Two simple hard-cube models of gas-surface collisions are re-examined in light of recent argon–tungsten atomic beam scattering experiments. Both models provide a good description of the average energy exchange. The inclusion of a square well attraction to the hard-wall potential results in an accurate two parameter fit to the data. The derived well depth is in agreement with previous measurements of the heat of desorption.

An investigation of the temperature programmed desorption (TPD) of CO and D2 from Ni(111) has been carried out. It has been shown that a differential method for the extraction of the kinetic parameters, threshold temperature programmed desorption (TTPD), can be applied with accuracy near the limit of zero coverage. In this limit, agreement is found between integral and differential methods for kinetic parameter evaluation. The factors which limit the applicability of TTPD are explored and a method to verify its proper application is presented.

We have investigated the surface morphology of relaxed, compositionally graded GexSi1−x structures, to illustrate the influence of defect-related strain fields on film growth. Quantitative topographic measurements via scanning force microscopy show that the roughness associated with the cross-hatch patterns, due to underlying misfit dislocations beneath the surface, increases as the final Ge concentration or the grading rate increases. We further show that strain fields arising from the termination of threading dislocations at the surface result in shallow depressions.

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We report molecular beam scattering of hyperthermal Xe atoms over an energy range 1<Ei(eV)<10 from single crystal surfaces of GaAs(110), Ag(100), and Ge(100). The angular distributions from the corrugated surfaces show sharp backscattered rainbow maxima related to the topography of the crystal surface. In contrast the smooth surfaces yield quasispecular lobes suggestive of structure scattering. The large energy loss for all surfaces scales on average with the energy of local normal motion. A simple binary interaction model is developed which accounts for many of the phenomena observed from corrugated surfaces. With the aid of a comparison classical trajectory study, these results provide some understanding of the mechanism by and extent to which a solid can dissipate the energy of a hyperthermal collision.