Stressed Silicon Nitride Nanomechanical Resonators at Helium Temperatures

Abstract

We have characterized the mechanical resonance properties (both linear and nonlinear) of various doubly-clamped silicon nitride nanomechanical resonators, each with a different intrinsic tensile stress. The measurements were carried out at 4 K and the magnetomotive technique was used to drive and detect the motion of the beams. The resonant frequencies of the beams are in the megahertz range, with quality factors of the order of 10 4 . We also measure the dynamic range of the beams and their nonlinear (Duffing) behaviour.

Thermal conductivity of silicon nitride membranes is not sensitive to stress

“…Data taken at 4.2 K in vacuum. silicon nitride density (3 g/cm 3 ) and h the beam length 22 . We find a stress value of about 0.85 GPa for the HS silicon nitride, which confirms that the membrane is still stressed after releasing and 0.12 GPa for the LS silicon nitride.…”

“…This technique allows the measurement of both thermal conductivity and specific heat of a given membrane within the same experiment over a broad temperature range. The mechanical dissipation and stress amplitude of both HS and LS substrates are also measured at cryogenic temperatures by means of nanomechanical resonators 22 . We show experimentally that thermal conduction is essentially independent of the stress stored in this material.…”

Slippage and Boundary Layer Probed in an Almost Ideal Gas by a Nanomechanical Oscillator

“…The NEMS fabrication and design can be found in Ref. [27]. It is excited and detected by means of the magnetomotive scheme [28].…”

Modelling and observation of nonlinear damping in dissipation-diluted nanomechanical resonators

“…Here, we investigate nonlinear effects in dissipation-diluted membrane resonators with very high Q-factors. Whereas the Duffing effect (nonlinear frequency shift) has been observed in stressed nanomechanical resonators before [22][23][24], we focus on nonlinear damping here [19,25]. Starting from a full threedimensional model (von Kármán theory) we derive analytical expressions for the expected nonlinearities, both in terms of Duffing frequency shift and nonlinear damping.…”