ABSTRACT
This chapter aims synthesize semiconductor/oxide composite nanowires (NW) via molecular beam epitaxial growth and subsequent wet oxidation. Selective oxidation applied to the GaAs/AlGaAs core–shell NWs grown on silicon substrates was used to fabricate GaAs/AlGaOx NWs. To realize efficient white light emitters, it is essential to prevent the transfer of carriers to the GaAs core and the shell surface. The AlGaAs/GaAs system was subjected to wet oxidation to integrate oxide functions into the semiconductor. Wet oxidation transforms the AlGaAs compound semiconductor into the amorphous oxide AlGaOx, resulting in high refractive index contrast between the materials before oxidation as well as current confinement because of the insulating nature of the oxides. GaAs/AlGaAs core–shell NWs were grown by molecular beam epitaxy on Si substrates. By extension and coalescence of AlGaAs shell, the system forms a fully buried structure. GaAs/AlGaAs heterostructure NWs were buried in the oxide shells by expanding the shell diameter to form planar structures that can be applied to future devices.
