Three-dimensional ZnO nanostructure photodetector prepared with through silicon via technology.

A ZnO-nanowire photodetector was prepared using three-dimensional through silicon via (TSV) technology. The diameter and depth of the Si via were about 80 μm and 170 μm, respectively. Cu uniformly filled in each TSV, whose average resistance was about 0.9  mΩ. For the three-dimensional ZnO-nanowire photodetector, the photocurrent increased rapidly with a time constant of about 1 s when ultraviolet excitation was applied. The on-off current ratio was about 10⁴.