Characterization of Nanowire Devices Using Nano-Focused X-Ray Beams

The long absorption length of hard X-rays makes them ideal tools for investigating electronic and optoelectronic devices in realistic operational conditions. Modern X-ray optics reach the relevant length scales for single nanoelectronic devices. Here, methods to investigate single nanowire devices with nanofocused X-rays are discussed. The X-rays are used both as pump and probe of semiconductor nanowire devices. Nanofocused X-ray diffraction was used to quantify bending and lattice tilt in strained core-shell nanowires as well as electrically biased nanowire devices. The carrier collection in single solar cell nanowires was probed with X-ray beam induced current. X-ray fluorescence mapping at 50 nm spatial resolution of Zn doping in solar cell nanowires revealed background doping and long gradients. The demonstrated methods are relevant for a wide range of nanoscale semiconductor devices.