Defect-free InAs nanowires self-catalyzed growth on graphene/Ge by molecular beam epitaxy

【摘要】 In As nanowires(NWs) self-catalyzed grown on graphene surface frequently exhibit a large number of stacking-fault defects.However,the control of these defects in InAs NWs still remains a large challenge,which significantly limits the applications of In As NWs in electronics and optoelectronics.In this work,the self-catalyzed growth of In As NWs on graphene/Ge substrate by molecular beam epitaxy(MBE) is systematically investigated.Growth models for In As NWs and parasitic islands on graphene/Ge are developed.Through rational design of growth parameters,the self-catalyzed growth of defect-free InAs NWs on graphene surfaces is ultimately achieved.Our experimental results indicate that lower growth temperature can effectively suppress the formation of stacking-fault defects in InAs NWs,no visible stacking-fault defects are observed in the samples grown below 510℃,and the intrinsic mechanism for this is clarified with the density functional theory(DFT) calculations.更多还原

【Abstract】 In As nanowires(NWs) self-catalyzed grown on graphene surface frequently exhibit a large number of stacking-fault defects.However,the control of these defects in InAs NWs still remains a large challenge,which significantly limits the applications of In As NWs in electronics and optoelectronics.In this work,the self-catalyzed growth of In As NWs on graphene/Ge substrate by molecular beam epitaxy(MBE) is systematically investigated.Growth models for In As NWs and parasitic islands on graphene/Ge are developed.Through rational design of growth parameters,the self-catalyzed growth of defect-free InAs NWs on graphene surfaces is ultimately achieved.Our experimental results indicate that lower growth temperature can effectively suppress the formation of stacking-fault defects in InAs NWs,no visible stacking-fault defects are observed in the samples grown below 510℃,and the intrinsic mechanism for this is clarified with the density functional theory(DFT) calculations.更多还原