MONTE-CARLO SIMULATION OF ION-CHANNELING SPECTRA FROM PARTIALLY DAMAGED CRYSTALS

We have elaborated a new Monte Carlo program to simulate ion-channeling spectra from partially damaged crystals. This program provides the transverse-flux distribution together with the fractions of channeled and dechanneled ions, their average energies, and energy fluctuations at any depth by calculating channeled-ion trajectories under a multistring potential. Thus we can determine the depth profiles of defects and dopant atoms, including preferential lattice positions as well as atomic configurations at interfaces. The present program is applied to deriving the depth profiles of defects induced by 100-, 150-, and 200-keV Ar+ irradiation upon GaP(111) crystals. Overall agreement is obtained between the present results and those determined from an analytic manner and calculated from a modified TRIM program, which simulates collision cascades in solids.