Application of synchrotron radiation to x-ray lithography

Synchrotron radiation from the German electron synchrotron DESY in Hamburg has been used for x-ray lithography. Replications of different master patterns (for magnetic bubble devices, Fresnel zone plates, etc.) were made using various wavelengths and exposures. High-quality lines down to 500 Å wide have been reproduced using very soft x rays. The sensitivities of x-ray resists have been evaluated over a wide range of exposures. Various critical factors (heating, radiation damage, etc.) involved with x-ray lithography using synchrotron radiation have been studied. General considerations of storage ring sources designed as radiation sources for x-ray lithography are discussed, together with a comparison with x-ray tube sources. The general conclusion is that x-ray lithography using synchrotron radiation offers considerable promise as a process for forming high-quality-submicron images with exposure times as short as a few seconds.