Exploring the Quality Factor of Quartz Crystal Resonator with N-M Asymmetric Electrode Structure in 3rd Overtone Mode

Recently, the quartz crystal microbalance (QCM) sensor with N-M asymmetric electrode structure operating in 3<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> overtone mode is reported during to its high sensitivity. The core parameter of the quartz crystal resonator decides the performance of the QCM sensor because that the main part of the QCM sensor is the quartz crystal resonator. Hence, the 3-overtone quality (Q<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>) factor characterizes the stability of QCM sensor with N-M asymmetric electrode structure operating in 3<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> overtone mode. However, there are few studies to report the Q<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> of the quartz crystal resonator with N-M asymmetric electrode structure. Herein, we studied the Q<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> of the quartz crystal resonator with N-M asymmetric electrode structure. The experimental results show that the Q<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> values are larger than 40000 and prove that the QCM sensor with N-M asymmetric electrode structure operating in 3<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> overtone mode is reliable. Additionally, the actual Q<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> is 1.93~3.78 times that of the nominal 3-overtone quality factor (Q’<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>). These performance parameters show that the QCM sensors with N-M asymmetric electrode structure have excellent stability and they can be reliably applied in many fields.