First direct measurements of dissipation mechanisms in MEMS resonators
Abstract/Contents
- Abstract
- Microelectromechanical systems (MEMS) have become ubiquitous and are used in all modern electronics, from cell phones to satellites. With the never-ending demand for smaller, lighter, faster electronics that consume less power, designing MEMS components that dissipate less energy, i.e., have a higher Quality Factor (Q), has become even more crucial. This dissertation presents a novel methods of measuring the Q of microelectromechanical systems (MEMS) at low temperature that enables the elimination of the thermal expansion coefficient (CTE). At in-depth investigation of the CTE using families of DETF resonators created by means of the epi-seal encapsulation process with different crystal orientations was performed. Experiments were performed with the purpose of eliminating CTE, and, consequently, rendering negligible the effects from thermoelastic dissipation (TED). Our results demonstrate that this measurement method enabled the first direct examination of the strength of anchor damping in tuning fork resonators, which allowed us to study the effect of anchor design and other factors on anchor damping. Our results reveal an unanticipated impact that structures far away from the anchor have on anchor damping, which is contradictory to many predictions of conventional models for anchor damping. A second finding about anchor damping, presented for the first time, is that not only can this damping term be clearly seen in WE mode devices, but it also shows a clear temperature dependence. Furthermore, Lame-mode resonators at low temperature enabled the first direct detection of Akhiezer damping in a MEMS resonator. Akhiezer damping, first identified by Akhiezer in 1965, has been the focus of extensive research. Several theoretical studies have focused on Akhiezer damping near room temperature; however, direct detection of Akhiezer damping has proved difficult because other, stronger dissipation mechanisms have precluded experimental analysis over a wide range of temperatures. For this work a novel apparatus and methods were developed that enabled us to do the first direct examination of Akhiezer damping in MEMS resonators by measuring the f*Q product. Our results provide the first clear, direct detection of Akhiezer dissipation in MEMS resonator, which is widely considered to be the ultimate limit to Q in MEMS devices.
Description
| Type of resource | text |
|---|---|
| Form | electronic resource; remote; computer; online resource |
| Extent | 1 online resource. |
| Place | California |
| Place | [Stanford, California] |
| Publisher | [Stanford University] |
| Copyright date | 2018; ©2018 |
| Publication date | 2018; 2018 |
| Issuance | monographic |
| Language | English |
Creators/Contributors
| Author | Rodriguez, Janna |
|---|---|
| Degree supervisor | Kenny, Thomas William |
| Thesis advisor | Kenny, Thomas William |
| Thesis advisor | Harris, J. S. (James Stewart), 1942- |
| Thesis advisor | Howe, Roger Thomas |
| Degree committee member | Harris, J. S. (James Stewart), 1942- |
| Degree committee member | Howe, Roger Thomas |
| Associated with | Stanford University, Department of Mechanical Engineering. |
Subjects
| Genre | Theses |
|---|---|
| Genre | Text |
Bibliographic information
| Statement of responsibility | Janna Rodriguez. |
|---|---|
| Note | Submitted to the Department of Mechanical Engineering. |
| Thesis | Thesis Ph.D. Stanford University 2018. |
| Location | electronic resource |
Access conditions
- Copyright
- © 2018 by Janna Rodriguez
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