  This work reports on a technology-agnostic and frequency-independent
methodology combining a-priori modeling, Finite Element Analysis (FEA), and
experimental results for the characterization of acoustic losses in
interdigitated piezoelectric micro- and nano-electromechanical (M/NEMS)
resonators. The proposed approach models the mechanical quality factor (Qm) and
its dependency on piezoelectric (Qpiezo) and metal (Qmetal) acoustic losses, as
a function of the mode of vibration dispersion characteristics. The model is
finally experimentally validated by exploiting the intrinsic on-chip
multifrequency manufacturability of interdigitated devices. A broad range of
available resonator technologies, frequencies, and piezoelectric materials are
investigated for this purpose, including bulk X-cut Lithium Niobate (XLN) leaky
surface acoustic wave resonators operating at Ultra High Frequency (UHF), thin
film XLN Lamb Wave resonators spanning between Very High Frequency (VHF) and
the Ku band, and Aluminum Nitride (AlN) and scandium-doped AlN (ScAlN)
cross-sectional lame' mode resonators ranging from the Ku to Ka band (mmWave).
