Improving the mechanical quality factor of ultra-low-loss silicon resonators
Abstract
In its as-fabricated state, a silicon mechanical resonator with a very high quality factor at liquid helium temperatures is found to have two energy loss mechanisms which can be removed with a 3 h anneal at 300 °C. Because of the silicon wafer processing history, these mechanisms are likely introduced during the resonator fabrication process. One energy loss mechanism contributes to the overall background damping over the entire measured temperature range, 400 mK ≤ T ≤ 300 K, at a level of ΔQ−1≈3×10−9, and gradually reappears after aging on the order of 100 d timescales. The second energy loss mechanism is a broad peak, ΔQ−1≈2×10−8, centered near 100 K. This peak does not re-appear upon aging and is tentatively attributed to the tetrafluoromethane reactive ion etch step, despite the fact that the silicon resonator is protected with silicon nitride and photoresist during the process.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 19, 2018
- Source ID
- 10.1063/1.5027486
Entities
People
- Matthew R. Abernathy
- Thomas H Metcalf
- Xiao Liu
Organizations
- Nuclear Regulatory Commission
- Office of Naval Research
- United States Naval Research Laboratory