陀螺儀作為其中一種傳感器，在各種大型器械或是精密儀器中相當常見，在MEMS(microelectromechanical systems)的尺度下，圓盤形陀螺儀DRG (disk resonator gyroscope)的發展行之有年，本論文主要討論近年來於MEMS尺度下蓬勃發展的半球殼形陀螺儀HRG (hemispherical resonator gyroscope)。而陀螺儀的基本性能由品質因數Q(quality factor)影響最深， 值是基於各種物理損耗機制所帶來的能量損耗總和，其中包含熱彈性阻尼損耗、錨固定損耗、電極損耗等。經由陀螺儀結構的最佳化，可以使其他機械損耗都降至最低，但是由材料性質所主導的熱彈性阻尼損耗卻無法經由結構設計去降低，完全取決於材料本身的性質，於是就成為了左右Q值的重要損耗項，此時材料選用對於陀螺儀及各式諧振器會造成很大的影響，最常見的材料為二氧化矽。本文欲探討在MEMS的尺度下，以各式半導體材料取代二氧化矽，並且於其中能貢獻最大Q值的β-Ga2O3作主要的說明與相關分析，並且討論半導體材料相對於一般材料的優勢以及提升陀螺儀性能的前景，本論文使用有限元素分析軟體ANSYS與微機電分析軟體CoventorWare對不同的諧振陀螺儀進行分析並且求取Q值，配合上Q值的解析解相互對照比較，最後也會設計實驗步驟來收集β-Ga2O3樑諧振器的實際Q值以佐證材料的優勢性。

As one of the sensors, gyroscope is quite common in various large-scale instruments or precision instruments. At the scale of microelectromechanical systems (MEMS), the development of disk resonator gyroscope (DRG) has been in progress for many years. Here we want to disscuss the hemispherical resonator gyroscope (HRG) that has flourished in the MEMS scale in recent years. The basic performance of the gyroscope is most affected by the quality factor Q. Q-1 is the sum of the energy losses caused by various physical loss mechanisms, including the thermoelastic damping, the anchor loss, and the electrode loss. Through the optimization of the gyroscope structure, other mechanical losses can be minimized, but thermoelastic damping dominated by the material properties can not be reduced by structural design, it depends on the property of the material itself, so it becomes the most important loss term of Q. For the reasons above, material selection will have a great impact on the gyroscope and various resonators, the most common material for which is silicon oxide. In this thesis, we will discuss the substitution of silicon oxide with various semiconductor materials at the MEMS scale, especially β-Ga2O3 which can contribute to enhanced Q, and discuss the advantages of semiconductor materials relative to insulting materials. Finite element analysis software ANSYS and the MEMS analysis software CoventorWare are used to analyze different resonant gyros and obtain the Q values. Experimental procedures were performed to collect the actual Q of β-Ga2O3 beam resonators.

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