A method for permanently bonding two silicon wafers so as to realize a uniform enclosure is described. This includes wafer preparation, cleaning, RT bonding, and annealing processes. The resulting bonded wafers (cells) have uniformity of enclosure ~1%1,2. The resulting geometry allows for measurements of confined liquids and gasses.
Thomson, S. R. D., Perron, J. K., Kimball, M. O., Mehta, S., Gasparini, F. M. Fabrication of Uniform Nanoscale Cavities via Silicon Direct Wafer Bonding. J. Vis. Exp. (83), e51179, doi:10.3791/51179 (2014).