## 8 Conclusions  
This study has made unique contributions in the field of MEMS by successfully demonstrating the capabilities of a novel hybrid MEMS resonator design that integrates capacitive and piezoelectric transduction mechanisms. This resonator has effectively addressed and overcome some of the fundamental limitations associated with traditional MEMS resonators, particularly in terms of quality factor, insertion loss, and motional impedance, by leveraging the unique advantages of both capacitive and piezoelectric effects within a single device. A notable achievement of this hybrid MEMS resonator is its exceptional ability to minimize parasitic effects that often hinder conventional resonators. The in  
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**Reference** & **Fabrication Method** & **Piezoelectric Material** & **Resonator Body Material** & **Electrode Material Piezoelectric and Capacitive** & **Resonator Shape and Mode** & **Features** \\ \hline \multirow{37}{*}{[37]} & \multirow{3}{*}{AIN-HARPSS} & \multirow{3}{*}{AIN} & High-Resistivity Silicon (\(>\)1000 \(\Omega\)-cm) & Molybdenum Polysilicon & Concave bar Width extensional mode & Reaching very high \(>\) 1000 \({}^{\circ}\)C annealing temperature \\ \cline{1-1} \cline{3-6}  & & & & Aluminum Doped Silicon & Disk-shaped Wine-glass mode & Design restrictions from the fabrication methods \\ \hline \multirow{3}{*}{This Work} & \multirow{3}{*}{In-house fabrication} & \multirow{3}{*}{ZnO} & Low-Resistivity Silicon & Ruthenium Nickel & Lateral extensional Contour mode & High performance at lower temperatures, Q-factor \(>\) 28,000, parasitic mitigation, lower bias voltage, advanced integration method \\ \cline{1-1} \cline{3-6}  & & & & & &  
tegrration of the two transduction mechanisms is instrumental in significantly reducing parasitic feedthrough, which is a critical barrier in the performance of RF MEMS resonators. By configuring the device to harness the piezoelectric effect for sensing and capacitive (electrostatic) forces for actuation, the resonator demonstrates a substantial decrease in the unwanted signal pathways that typically lead to signal degradation, particularly at higher frequencies. The mitigation of the parasitic effects leads to an improvement in the signal-to-noise ratio, making the hybrid resonator highly effective for precision applications where signal quality and integrity are crucial. Additionally, the resonator shows a remarkable quality factor exceeding 28,000 while operating effectively at frequencies up to 20 MHz. These achievements not only validate the design concept but also highlight the potential of hybrid MEMS resonators to push the frontiers of current RF MEMS technology, offering more reliable and efficient on-chip resonator solutions for advanced telecommunications and electronic warfare systems by combining the advantages of capacitive and piezoelectric mechanisms. This hybrid approach enhances the resonator's performance in terms of quality factor, making it a versatile and robust component for next-generation communication systems. The successful implementation of this new hybrid design marks a pivotal advancement in resonator technology, illustrating a powerful approach to overcoming the traditional trade-offs between performance parameters in MEMS resonators for instance high frequency selectivity filters and high performance oscillators are key components and sub-system modules for communication transceivers. These systems are based on high-\(Q\) factor, low parasitic resonators capable of spurious-mode free operation.