Fig. 5: Hot electron induced selective oxidization.

a Line scan along the nanowire of Ga K-edge energies (colored dot symbol lines on the left y-axis) for the different applied bias voltages. The X-ray beam induced current (XBIC) signal (grey, solid line on the right y-axis) for 0 V is additionally displayed to precisely locate the position of the p–n junction. b, c Schematic band diagrams along the p–n junction explaining the observed oxidization in the n-doped part due to hot electrons accelerated by the built-in voltage at the p–n junction. d Colorized SEM image of the device after all measurements (tilted by 50° with respect to the sample surface). The dashed line indicates the measurement region for the high-resolution XRF/XBIC maps. Below: overview SEM image of the nanowire device.