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Microelectromechanical systems (MEMS) have emerged as highly attractive alternatives to conventional commercial off-the-shelf electronic sensors and systems due to their ability to offer miniature size, reduced weight, and low power consumption (i.e., SWaP advantages). These features make MEMS particularly appealing for a wide range of critical applications, including communication, biomedical, automotive, aerospace, and defense sectors. Resonant MEMS play crucial roles in these applications by providing precise timing references and channel selections for electronic devices, facilitating accurate filtering, mixing, synchronization, and tracking via their high stability and low phase noise. Additionally, they serve as key components in sensing applications, enabling detection and precise measurement of physical quantities for monitoring and control purposes across various fields. Temperature stability stands as a paramount performance specification for MEMS resonators and oscillators. It relates to the responsivity of a resonator's frequency to temperature variations and is typically quantified by the temperature coefficient of frequency (TCf). A constant and substantially large absolute TCf is preferred in MEMS temperature sensing applications, while a near-zero TCf is required for timing and other MEMS transducers that necessitate the decoupling of temperature effects on the resonance frequency. This comprehensive review aims to provide an in-depth overview of recent advancements in studying TCf in MEMS resonators. The review explores the compensation and engineering techniques employed across a range of resonator types, utilizing diverse materials. Various aspects are covered, including the design of MEMS resonators, theoretical analysis of TCf, temperature regulation techniques, and the metallization effect at high temperatures. The discussion encompasses TCf analysis of MEMS resonators operating in flexural, torsional, surface, and bulk modes, employing materials such as silicon (Si), lithium niobate (LiNbO3), silicon carbide (SiC), aluminum nitride (AlN), and gallium nitride (GaN). Furthermore, the review identifies areas that require continued development to fully exploit the TCf of MEMS resonators.
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Powering Wire-Mesh Circuits through MEMS Fiber-Grippers
Packaging electronic devices within electronic textiles and fibrous substrates requires an understanding of how fibers interact with circuit components in different operating conditions. In this paper, we use microeletromechanical (MEMS) devices to put devices in electrical contact with fine wires. We characterize the electronic properties of MEMS-to-wire contacts and discuss general guidelines for optimizing the design of these grippers and potential MEMS-based circuits. We then demonstrate how these grippers can act as non-rigid circuit components that effectively transfer power to devices such as LEDs. Analysis shows that our grippers are suitable conductors (under 150 Ohms) under standard operating temperatures (25-100 deg. C) with potential for use as sensors for current overflow or temperature. Methods such as parylene deposition and silver epoxy to stabilize MEMS performance are briefly discussed and explored.
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- PAR ID:
- 10480854
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- 2023 IEEE International Conference on Flexible and Printable Sensors and Systems (FLEPS)
- ISSN:
- 2832-8256
- ISBN:
- 978-1-6654-5733-0
- Page Range / eLocation ID:
- 1 to 4
- Subject(s) / Keyword(s):
- MEMS E-Textiles Fabrication
- Format(s):
- Medium: X
- Location:
- Boston, MA, USA
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/FLEPS57599.2023.10220225
