Process latitude measurements on chemically amplified resists exposed to synchrotron radiation

Several chemically-amplified resists, positive and negative, have been evaluated for synchrotron x-ray lithography. Some have shown sensitivities as low as 10.1 mJ/cm2. Linewidths of 0.3 micron have been achieved in 1 micron thick single-layer resist with vertical sidewalls and good process latitude, at an x-ray dose of below 50 mJ/cm2. The chemically amplified resists are processed similarly to conventional resists using metal ion free aqueous base developers. Data re presented for resists from Shipley, Rohm and Haas, and Hoechst AG. Lithographic exposures were performed with the University of Wisconsin's Aladdin synchrotron, using the ES-1 beamline of the Center for X-ray Lithography.