Optimizing the atomic force microscopic parameters for submicron IDT patterns

Abstract

The experimental results of submicron lithography for making interdigital transducers (IDTs) by using an atomic force microscope (AFM) is presented in this work. The AFM is used in the tapping mode. For the transfer of high-quality patterns, three operational parameters, the probe speed, the distance from the surface to the tip, and the tip force applied on the device are shown to be important controlling parameters. Understanding and controlling the effects of these parameters during lithography would help to transfer high-quality submicron IDT pattern on the substrate. We show that aluminum IDT electrodes with 807nm widths can be directly patterned on Si substrates. Because the requirement is eliminated in the AFM lithography process, transferring the pattern of a submicron IDT is convenient and more accurate.