Fig. 5.

(a) SEM image of TAO nanotube on the silicon substrate before metallization. (b) SEM image of fully metallized TAO nanotube on silicon substrate. The brighter tone of the nanotube in b versus a indicates the increased ability of the metallized nanotube (nanowire) to absorb electrons. (c and d) SEM images showing metallized TAO nanotubes (circled in c), overlaid with chromium/gold electrodes patterned by electron-beam lithography and deposited by thermal vapor deposition. The electrodes are labeled A–E. (Scale bars = 1 μm.) (e) The current–voltage curves measured through the sections of TAO templated nanowire between the indicated electrodes.