Focused Ion Beam Lithography with Transition Metal Oxide Resists

Abstract

The microlithographic behavior of inorganic resists for focused ion beam (FIB) has been studied for thin amorphous films of WO₃, MoO₃, V₂O₅, a mixture thereof and Ta₂O₅ using 20∼70 keV Ga⁺ FIB. The exposure characteristics, composition at the film surfaces and electrical properties have been investigated in order to evaluate the mechanism of the microlithographic behavior. A study of line exposure indicates that the resolution of these resists is determined by the FIB diameter owing to their high contrast. It is also demonstrated that this resist work is directly applicable to fine patterning of W and Mo.