We have synthesized perpendicular SiOx nanowire (NW) arrays on Si substrates and investigated them using scanning electron microscopy. Transmission electron microscopy and energy-dispersive spectroscopy have been used to investigate the single NW structure. A near-infrared emission at 700 nm is observed. In/SiOx NW and In/SiOx thin film (TF) contacts exhibit Schottky behavior. The SiOx NW-based devices show six-fold improvements in photodetection efficiency in white-light illumination, compared to SiOx TF-based devices under reverse bias condition.