TEM Exposure
A through hole in a wafer can be closed down by a transmission electron microscope. Due to hydrocarbon buildup, the electrons stimulate hole closure. This method is very slow (taking over an hour to close a 100 nm hole). The slow method allows for great control of the hole size (since you can watch the hole decrease), but its drawback is that it takes a long time. Citation: T.Schenkel, V.Radmilovic, E.A.Stach, S.-J.Park, A.Persaud, J.Va.Sci.Tech.B 21, 2720 (2003).
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