Backscattering-energy spectra were measured for 2-MeV He ions channeled in 〈100〉 GaP, GaAs, and InP single crystals with natural oxide surface layers. The analysis of the experimental spectra was performed by the Monte Carlo simulation. The simulation program is based on the binary-collision model. The influence of the surrounding atoms and the energy loss of the channeled particles were taken into account. Also, different types of the ion-atom potential were tested. The simulated channeling spectra were calculated with respect to the random yield which makes it possible to fit experimental spectra without any normalization. Based on the simulation program, the thickness of the surface oxide layer, thermal vibration amplitudes of crystal atoms, and random stopping power of incident ions were determined. The values obtained were compared with the previously published theoretical and experimental data.

• Received 13 March 1989

DOI:https://doi.org/10.1103/PhysRevB.40.7704