We report a simple and inexpensive approach to the fabrication of enclosed nanoscale channels composed of silica nanoparticles on planar Si surfaces using interferometric lithography to define the long-range pattern in a photoresist film followed by spin-cowing self-assembly of colloidal silica nanoparticles and high-temperature calcination to remove the photoresist leaving open nanochannels. Channel structures with channel width and height ranging front similar to 100 run to over 1 mu m were formed over large areas with different particle sizes and channel profiles. The dimensional scale of these ordered arrays of enclosed channels can be easily controlled through the parameters in the photoresist patterning and the spin-coating steps. Complex, multilayer structures have been generated using this approach as well. This process opens it route to fabricating ordered enclosed nanochannels with potential uses in photonics, molecular/biological sensors, biological separations and catalysis. (c) 2005 American Vacuum Society.