ABNORMAL ENERGY DEPENDENCE OF AXIAL MINIMUM CHANNELING YIELDS IN Ge_xSi_1-x/Si(100) STRAINED

An energy dependence of the axial minimum channeling yield in Ge_xSi_1-x/Si(100) Strained-layer superlattice is observed in the energy range of impinging He⁺ ione from 1.2 to 3.0 MeV. For 100 axial channeling, the measurements ere in agreement with what have been known in a single crystal. However, for 110 axial channeling, it is found that the minimum channeling yields increase markedly with the increase of He⁺ ion energy, which is contrary to the general channeling behaviors in a single crystal. A tentative model is suggested to explain this aberrance.