表題番号：2020C-658
日付：2021/03/31
研究課題モード局在化センサにおけるばね定数の無限小化による感度向上の研究
| 研究者所属（当時） | 資格 | 氏名 | |
|---|---|---|---|
| （代表者） | 理工学術院 大学院情報生産システム研究科 | 准教授 | 池橋 民雄 |
| （連携研究者） | Waseda IPS | Master Student | Zhiqiang Chen |
- 研究成果概要
- Sensors using mode localization can attain high sensitivity with the use of weakly coupled resonators. In mode-localized tilt sensors, the sensitivity is known to be proportional to Δ𝑘/𝑘𝑐, where Δ𝑘 is a spring constant shift caused by a tilting and 𝑘𝑐 is a stiffness of the coupling spring. This suggests that high sensitivity can be attained at 𝑘𝑐→0. In view of this, we considered a structure that can attain 𝑘𝑐→0. In the proposed structure, the small coupling spring 𝑘𝑐 is attained by combining a mechanical spring and an "electrical spring" which is composed by parallel plate electrodes. Due to the electrostatic attractive force, the electrical spring behave as a spring with negative spring constant. The effective spring constant of the electrical spring can be tuned a voltage applied to the electrode. Thus by optimizing the voltage, the total spring constant can be made zero. The voltage tunability also enables compensation of temperature dependence and process variation of the spring constant. Using a FEM simulator, we have designed a mode-localized tilt sensor that possesses this coupling spring and verified that the spring constant can be made zero by optimizing the voltage. We also confirmed the increase of sensitivity at 𝑘𝑐→0.