Stress and Silicon Nitride: A Crack in the Universal Dissipation of Glasses

High-stress silicon nitride microresonators exhibit a remarkable room temperature Q factor that even exceeds that of single crystal silicon. A study of the temperature dependent variation of the Q of a 255 mu mx255 mu mx30 nm thick high-stress Si(3)N(4) membrane reveals that the dissipation Q(-1) decreases with lower temperatures and is similar or equal to 3 orders of magnitude smaller than the universal behavior. Stress-relieved cantilevers fabricated from the same material show a Q that is more consistent with typical disordered materials. e-beam and x-ray studies of the nitride film's structure reveal characteristics consistent with a disordered state. Thus, it is shown that stress alters the Q(-1), violating the universality of dissipation in disordered materials in a self-supporting structure.