On controlling EBL parameters for nanoelectromechanical resonators fabricated on insulating/semiconducting structures

The current work details the development and optimization of the fabrication processes for nanoelectromechanical resonators such as surface and bulk acoustic wave (SAW/BAW) devices that operate in GHz range, specifically based on nano-interdigitated transducers (n-IDTs). The method combines electron-beam lithography (EBL) and lift-off process to fabricate the n-IDTs with finger patterns having line widths of the order of 100 nm on AlN/UNCD(aluminum nitride/ultrananocrystalline diamond) combined structures deposited on crystalline silicon. The widespread availability of this method has led to the study of the combination of processing parameters for both EBL and lift-off for its application in the realization of n-IDTs. The fabricated devices exhibited high frequency range up to 15 GHz with minimum stop-band rejection of 25dB. Excellent filtering response of the devices and the compatibility of fabrication processes with existing manufacturing technologies pave the way towards advanced AlN/UNCD based nano-resonantors.