Semiconductor nanowires are structures with an extremely high aspect ratio and a diameter typically smaller than 100 nm. In bottom-up approaches, feature sizes down to 10 nm and below can be achieved without any lithography. Complementary top-down approaches offer higher level of control, in particular for the fabrication of regular nanowire arrays. The quasi-one-dimensional shape and the nanometric size of nanowires result in unique properties, often independently of the concrete nanowire material. Their characteristics make nanowires an exciting subject for fundamental studies and offer many conceptual advantages for various applications.
The goal of our research is to inspire and demonstrate new functionalities for optoelectronic applications by employing III-V nanowires. To this end, we investigate fundamental nanowire properties that crucially influence such applications and assess nanowire suitability. We grow both group-III-nitride and group-III-arsenide nanowires by molecular beam epitaxy but pursue also top-down approaches. We analyze nanowire microstructure and optical as well as electronic properties, and we employ technology to guide growth, enable electrical measurements, and process demonstrator devices.