Studies on sensitivity and etching resistance of calix[4]arene derivatives as negative tone electron beam resists

Several lower rim derivatives of calix[4]arene are compared as high resolution negative tone resists for electron beam lithography (EBL). The sensitivity of these derivatives is discussed in this paper. The suitability of calix[4]arene derivatives as top layers in bilayer resist systems is evaluated in studies on the etching resistance in an oxygen plasma. It is demonstrated that etching resistance can be improved by silylation of the resist molecules. The use of tetra(trimethylsilyloxy)calix[4]arene is compared to a common silylation step of an exposed tetraallylcalix[4]arene resist.