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In electron beam lithography, the matter wave length of electron, which be added 20 keV voltage, is pproximately 10-11m. The wave length is smaller than 193 nm or 157 nm that the Optical lithography excimer laser wave length has. In general, the electron beam lithography has the very good ability of high resolution, and the resolution can reach several nm degree(ignoring exposure depth).The electron beam lithography can be used in photo masks fabrication, direct e-bean writing, and nanometer structures fabrication. In our article, we try to fabricate high aspect ratio 2-D cylinder array structure. The desire of diameter is smaller than 150 nm, height is higher than 2 mm, and the lattice const is 300 nm. We want to use e-bean lithography and reactive ion etching (RIE) to fabricate the desired size. We must make up the etching mask, then try the RIE parameter. We try the positive and negative photo resist at the same time in order to choosing the best method. The changes of RIE parameters will make the change in the etching structures and height. We try to change the etching time, power, pressure and ratio of the gas, and compare the RIE result. In this way, we want to get the best RIE parameters for helping us to fabricate the desired structures.
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