Structural fabrication using cesium chloride island arrays as a resist in a fluorocarbon reactive ion etching plasma

Arrays of hemispherical islands of cesium chloride are formed on an oxidize d silicon wafer when a deposited thin film of CsCl is subsequently exposed to water vapor. High packing densities, P, and a wide, preselectable range of mean diameter, <d>, can be obtained. Use of such arrays for nanoscale li thography is demonstrated. Silicon pillars and cones have been fabricated w ith CsCl used as resist in a fluorocarbon reactive ion etching scheme. Cone s of tip angle 28 degrees and P = 0.18 and <d> = 85 +/- 20 nm were made. Th e wall angle as a function of etching parameters was determined. CsCl array s were used in a negative resist strategy, by coating the substrate and the hemispheres in aluminum and then lifting off the CsCl (with their Al coati ng). Wells were made in the exposed SiO2 on Si with <d> = 920 +/- 150 nm wi th a packing density of P = 35. Applications to field emission systems are noted. (C) 1999 The Electrochemical Society. S1099-0062(99)04-028-6. All ri ghts reserved.