Model and Observations of Dielectric Charge in Thermally Oxidized Silicon Resonators
This paper investigates the effects of dielectric charge on resonant frequency in thermally oxidized silicon resonators hermetically encapsulated using ¿epi-seal.¿ SiO 2 coatings are effective for passive temperature compensation of resonators but make the devices more susceptible to charging-relate...
Gespeichert in:
Veröffentlicht in: | Journal of microelectromechanical systems 2010-02, Vol.19 (1), p.162-174 |
---|---|
Hauptverfasser: | , , , , , , , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext bestellen |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | This paper investigates the effects of dielectric charge on resonant frequency in thermally oxidized silicon resonators hermetically encapsulated using ¿epi-seal.¿ SiO 2 coatings are effective for passive temperature compensation of resonators but make the devices more susceptible to charging-related issues. We present a theoretical model for the electromechanical effects of charge trapped in the dielectrics within the transduction gap of a resonator. Observations of resonance frequency against varying resonator bias voltage are fitted to this model in order to obtain estimates for the magnitude of the trapped oxide charge. Statistics collected from wet- and dry-oxidized devices show that lower fixed oxide charge can be expected upon dry oxidation. In addition, observations of time-varying resonator frequency indicate the presence of mobile oxide charge in a series of voltage biasing and temperature experiments. |
---|---|
ISSN: | 1057-7157 1941-0158 |
DOI: | 10.1109/JMEMS.2009.2036274 |