Development of the high voltage e-beam lithography system

High voltage electron beam lithography has a number of advantages over conventional 50kV-voltage e-beam lithography systems, such as reducing proximity effect, reducing line-width variation, and obtaining high aspect ratios of line height to gap width. The new high voltage e-beam lithography system is based on a JEOL JEM2000EX Transmission Electron Microscope (TEM) with scanning system. As the sample is immersed in the high intensity magnetic field during the exposure process, the movement of electrons in the resist and substrate is limited in a smaller area. By using this system to carry out some exposure experiments, we have obtained the structure with 10:1 high-width aspect ratio on a 3-micron-thick PMMA layer with a large area.