Self-Sealing Complex Oxide Resonators.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35119289.
- Also identified by DOI 10.1021/acs.nanolett.1c03498 and PMC identifier 8880390.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Although 2D materials hold great potential for next-generation pressure sensors, recent studies revealed that gases permeate along the membrane-surface interface, necessitating additional sealing procedures. In this work, we demonstrate the use of free-standing complex oxides as self-sealing membranes that allow the reference cavity beneath to be sealed by a simple anneal. To test the hermeticity, we study the gas permeation time constants in nanomechanical resonators made from SrRuO<sub>3</sub> and SrTiO<sub>3</sub> membranes suspended over SiO<sub>2</sub>/Si cavities which show an improvement up to 4 orders of magnitude in the permeation time constant after annealing the devices. Similar devices fabricated on Si<sub>3</sub>N<sub>4</sub>/Si do not show such improvements, suggesting that the adhesion increase over SiO<sub>2</sub> is mediated by oxygen bonds that are formed at the SiO<sub>2</sub>/complex oxide interface during the self-sealing anneal. Picosecond ultrasonics measurements confirm the improvement in the adhesion by 70% after annealing.