Non-lithographic growth of core-shell GaAs nanowires on Si for optoelectronic applications

We demonstrated a nonlithographic method for integrating GaAs nanowire (NW) array-based light-emitting diodes (LEDs) on silicon (Si) substrates. A sub-100 nm hole array on a deposited SiO₂ layer was patterned on an entire 2 in. Si wafer based on a sacrificed self-assembled InAs NW array. Then, a core-shell n-p junction GaAs NW array was grown on exposed Si windows via the selective-area growth method. The electrical properties of the core-shell n-p junction GaAs NW has been measured and compared to those of the core-shell junction NWs formed via the self-assembled growth method. Room temperature electroluminescence was successfully observed from the fabricated GaAs NW array-based LEDs. The core-shell junction III-V NW array epitaxially grown on a ubiquitous Si platform could be applied to future low-cost optical devices.