Coaxial ZnSe/Si nanocables with controlled p-type shell doping

Coaxial ZnSe/Si nanocables were successfully produced by a simple two-step growth method. ZnSe nanowire cores were first synthesized by thermal evaporation and then followed by the chemical vapor deposition (CVD) growth of Si shells. The former have a cubic single-crystal structure with a longitudinal direction of [1-bar 1 1-bar], while the latter are polycrystalline and composed of a large number of Si crystal grains with dominantly (111) surfaces. Controlled p-type doping to the Si shells was implemented by B diffusion after the shell growth. Electrical measurements on the Si shells demonstrated that the shell conductivity could be tuned in a wide range of eight orders of magnitude by adjusting the B concentration, and a hole mobility of 11.7 cm2 V-1 s-1 and a hole concentration of 2 x 1015 cm-3 were revealed for the modestly doped Si shells. The ZnSe/Si core/shell nanocables have great potential in nano-optoelectronic applications.