The HARPSS process for fabrication of nano-precision silicon electromechanical resonators

390

219

MEMS-based oscillators are an emerging class of highly miniaturized, batch manufacturable timing devices that can rival the electrical performance of well-established quartz-based oscillators. In this review, a description is given of the key properties of a MEMS resonator that determine the overall performance of a MEMS oscillator. Piezoelectric, capacitive and active resonator transduction methods are compared and their impact on oscillator noise and power dissipation is explained. An overview is given of the performance of MEMS resonators and MEMS-based oscillators that have been demonstrated to date. Mechanisms that affect the frequency stability of the resonator, such as temperature-induced frequency drift, are explained and an overview is given of methods that have been demonstrated to improve the frequency stability. The aforementioned performance indicators of MEMS-based oscillators are benchmarked against established quartz and CMOS technologies.

Section: Resonator Impedancementioning

confidence: 99%

A review of MEMS oscillators for frequency reference and timing applications

Beek¹,

Puers²

2011

390

219

“…At the cost of a more expensive fabrication, this represents a huge advantage for frequency modulated sensors, as discussed in the next sections. Detailed description of fabrication technologies is not the main purpose of this manuscript, and the reader is redirected to [15][16][17][18][19] for in-depth analyses.…”

Section: Brief Overview Of Fabrication Technologiesmentioning

confidence: 99%

Silicon MEMS inertial sensors evolution over a quarter century

Langfelder

Bestetti

Gadola

2021

Silicon-based microelectromechanical systems (MEMS) inertial sensors have become ubiquitous, revolutionizing motion sensing, vibration sensing and accurate positioning in several societal fields. Driven by consumer and automotive markets, companies involved in this technological development focused mostly on low cost, miniaturization and low power consumption, somewhat sacrificing measurement accuracy. In several laboratories all over the world, however, the research toward higher-performance sensors has been going on for more than two decades, with the goal of improving two key parameters for future applications: noise density and bias stability. This review article summarizes, for silicon-based MEMS accelerometers and gyroscopes, the most relevant working principles that appeared in the scientific literature. The collection of several data about the above mentioned key figures enables tracing the roadmap for further developments in the upcoming decade.

Nonlinearity in micromechanical free–free beam resonators: modeling and experimental verification

Shao

Palaniapan

Tan

et al. 2008

In this paper, we present a systematic characterization and modeling technique for the micromechanical free-free beam resonator to analyze its nonlinear vibration behavior. Different from the conventional FEM-based approach whose simulation accuracy is usually limited around 60-70%, the proposed modeling method is able to accurately identify both the mechanical and electrostatic nonlinear parameters from just a few preliminary experimental observations. The nonlinear equation of motion is then numerically solved, demonstrating both the spring hardening and softening effects in the system. The simulated nonlinear behavior of the resonator under different driving conditions is validated by comparing them with the experimental data. In addition, based on the verified nonlinear model, design guidelines such as the nonlinearity cancellation are also highlighted. Although this work focuses on the free-free beam resonators, the proposed modeling approach can be applied to any other electrostatically driven microresonator to reveal different intrinsic nonlinear properties of the device.