In recent years it has been shown that the dissipation in strongly pre-stressed SiN strings is limited by defects in the amorphous material. For the case of a metallized SiN-Au bilayer system, we have carefully analyzed the evolution of both the eigenfrequency and the dissipation as a function of the metallization thickness.

See: Faust et al., Phys. Rev. B 89, 100102(R) (2014), Seitner et al., Appl. Phys. Lett. 105, 213101 (2014)