Silylation and dry development of chemically amplified resists SAL601*(1),AZPN114*(1), and epoxidised resist (EPR*(1)) for high resolution electron-beam lithography

A comparative study of high resolution positive imaging obtained after liqu id-phase silylation and dry development with two commercial and one experim ental electron-beam chemically amplified resists (CARs), namely SAL601, AZP N114, and EPR (EPoxidised Resist) is presented. 150 nm lines and spaces are obtained for all resists, while 100 nm lines are achieved with AZPN114 and EPR at 50 kV exposures. The exposure doses for AZPN114 and SAL601 are 10 m u C/cm(2) and 20 mu C/cm(2), respectively, while EPR is considerably faster (1.5 mu C/cm(2)). Chlorosilanes are used for EPR silylation, while SAL601 and AZPN114 are silylated with hexamethyl cycle tri silazane (HMCTS) or bis (di methyl amino) di silane (B(DMA)DS). SAL601 shows less silylation selec tivity between exposed and unexposed areas possibly due to insufficient cro sslinking. Implications of the presented processes on low-energy electron-b eam lithography are discussed.