Sub-micron camera for interdigital transducer fabrication

This paper describes the structure and operation of a sub-micron resolution camera system for fabricating high frequency interdigital electrode transducers (IDTs). A high resolution, 10× reduction lens is central to the system which produces IDTs by direct optical projection lithography. The camera resolution was determined experimentally to be approximately 0.75 μm. The system was subsequently used to fabricate a modified chirp transducer with linewidths ranging from 1 μm to 2.4 μm.