We present a new and simple approach to fabricate wafer-scale, thin encapsulated, two-dimensional nanochannels by using conventional surface-micromachining technology and thin-film evaporation. The key steps to the realization of two-dimensional nanochannels are a fine etching of a sacrificial layer to create underetching spaces at the nanometer regime, and an accurate thin-film evaporation for encapsulation. Well-defined cross-sectional, encapsulated nanochannel arrays with dimensions as small as 20 nm in both width and height have been realized at the wafer-scale. The fabricated nanochannels with a channel length of 10 mm have been used as a suitable fluidic platform for confining a solution containing nanomolar concentrations of Alexa fluorescent molecules. Initial results toward visualization of single Alexa molecules in the confined solution are reported.
Hoang Thi Hanh, H. T. H., Tong, H. D., Segers-Nolten, G. M. J., Tas, N. R., Subramaniam, V., & Elwenspoek, M. C. (2012). Wafer-scale thin encapsulated two-dimensional nanochannels and its application toward visualization of single molecules. Journal of colloid and interface science, 367(1), 455-459. https://doi.org/10.1016/j.jcis.2011.10.001