Nanoporous templates as hosts for nanowires offer a viable method for forming high density arrays of ordered, crystalline nanowires. Complete filling of the pores is vital in order to create electronic and optoelectronic devices. We have previously used conductive AFM and macrocontacts from both sides of membranes to determine the resistance of individual nanowires within a matrix. This approach was also used to conclude whether the nanowires went all the way though the filled porous membrane [1,2]. The drawback of this approach is that during two point measurements the contact resistance can not be extracted from the summary resistance. Access to full length of nanowires inside membranes permit conductivity measurements along the nanowire and exclude contact resistance from resitivity measurements.
Anodized aluminum oxide membranes containing semiconductor nanonowire arrays were incorporated in an epoxy matrix and the individual nanowires were exposed by polishing and etching. Exposed surfaces were visualized by scanning electron microscope Hitachi S 4800. Conductive AFM (Asylum research) in contact mode was applied for the surface conductivity mapping. The current through the individual nanowires of different length was measured and resistivity of the nanowires was determined. The resistance values are compared with the nanowire resistance obtained by the two and four point measurements.
The optical lithography technique was used for deposition of additional electrodes and device concepts on the crossection surfaces of nanowire matrix are proved.
1. D. Erts, B. Polyakov, B. Daly, M. A. Morris, S. Ellingboe, J. Boland, J. D. Holmes. J. Phys. Chem. B, 110, 820 (2006).
2. B. Polyakov, B. Daly, J. Prikulis, V. Lisauskas, B. Vengalis, J. D. Holmes, and D. Erts. Adv. Mater., 18, 1812 (2006).
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