Controlled In Situ Boron Doping Of Short Silicon Nanowires Grown By Molecular Beam Epitaxy

摘要

Epitaxial silicon nanowires (NWs) of short heights (～280 nm) on Si <111> substrate were grown and doped in situ with boron on a concentration range of 10~(15)-10~(19) cm~(-3) by coevaporation of atomic Si and B by molecular beam epitaxy. Transmission electron microscopy revealed a single-crystalline structure of the NWs. Electrical measurements of the individual NWs confirmed the doping. However, the low doped (10~(15) cm~(-3)) and medium doped (3 × 10~(16) and 1 × 10~(17) cm~(-3)) NWs were heavily depleted by the surface states while the high doped (10~(18) and 10~(19) cm~(-3)) ones showed volume conductivities expected for the corresponding intended doping levels.