Model and Observations of Dielectric Charge in Thermally Oxidized Silicon Resonators

被引:32
|
作者
Bahl, Gaurav [1 ]
Melamud, Renata [2 ]
Kim, Bongsang [3 ]
Chandorkar, Saurabh A. [4 ]
Salvia, James C. [1 ]
Hopcroft, Matthew A. [3 ]
Elata, David [5 ]
Hennessy, Robert G. [1 ]
Candler, Rob N. [6 ]
Howe, Roger T. [1 ]
Kenny, Thomas W. [4 ]
机构
[1] Stanford Univ, Dept Elect Engn, Stanford, CA 94305 USA
[2] SiTime Corp, Sunnyvale, CA 94085 USA
[3] Univ Calif Berkeley, Berkeley Sensor & Actuator Ctr, Berkeley, CA 94720 USA
[4] Stanford Univ, Dept Mech Engn, Stanford, CA 94305 USA
[5] Technion Israel Inst Technol, Mech Engn Microsyst Lab, Fac Mech Engn, IL-32000 Haifa, Israel
[6] Univ Calif Los Angeles, Sensors & Technol Lab, Los Angeles, CA 90095 USA
基金
美国国家科学基金会;
关键词
Charging; dielectrics; frequency drift; reliability; resonators; silicon dioxide; BULK ACOUSTIC RESONATOR; TEMPERATURE; FREQUENCY;
D O I
10.1109/JMEMS.2009.2036274
中图分类号
TM [电工技术]; TN [电子技术、通信技术];
学科分类号
0808 ; 0809 ;
摘要
This paper investigates the effects of dielectric charge on resonant frequency in thermally oxidized silicon resonators hermetically encapsulated using "epi-seal." SiO2 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. [2009-0088]
引用
收藏
页码:162 / 174
页数:13
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