Thin-film piezoelectric-on-silicon resonators for high-frequency reference oscillator applications

Abstract

This paper studies the application of lateral bulk acoustic thin-film piezoelectric-on-substrate (TPoS) resonators in high-frequency reference oscillators. Low-motional-impedance TPoS resonators are designed and fabricated in 2 classes--high-order and coupled-array. Devices of each class are used to assemble reference oscillators and the performance characteristics of the oscillators are measured and discussed. Since the motional impedance of these devices is small, the transimpedance amplifier (TIA) in the oscillator loop can be reduced to a single transistor and 3 resistors, a format that is very power-efficient. The lowest reported power consumption is approximately 350 microW for an oscillator operating at approximately 106 MHz. A passive temperature compensation method is also utilized by including the buried oxide layer of the silicon-on-insulator (SOI) substrate in the structural resonant body of the device, and a very small (-2.4 ppm/ degrees C) temperature coefficient of frequency is obtained for an 82-MHz oscillator.

A 4th-order band-pass filter using differential readout of two in-phase actuated contour-mode resonators

“…Lamb-wave MEMS resonators, where resonance frequency is set by lateral dimensions rather than the vertical dimension, have been proposed to overcome this issue. 3,4 Lamb-wave resonators are released from the substrate and therefore have a higher quality factor, which is crucial in synthesizing narrow-band channel select filters required in RF front-ends. [5][6][7] Lamb-wave filters are still in the research stage, and different filter configurations, such as mechanically and/or electrically coupling 5,8 methods, are under development.…”

Passive tuning in lateral-mode thin-film piezoelectric oscillators

“…aluminum nitride, AlN) sandwiched between two metal electrodes (e.g. molybdenum, Mo) stacked on top of the device layer of a silicon-on-insulator (SOI) substrate [9]. The bottom Mo is patterned to reduce the parasitic capacitor of the input and output traces.…”

Compositional Analysis of Adsorbed Organic Aerosol on a Microresonator Mass Sensor

“…Microresonators, which are micro-scale resonant masses, have seen growing popularity in a range of applications serving as reference oscillators (Abdolvand et al 2008), signal filters (Piazza et al 2007), and sensors (e.g., temperature (Jha et al 2007), acceleration (Zou et al 2014), and mass). Their development as particulate mass sensors is principally due to their high sensitivity, direct mass measurements (Wasisto et al 2016;Maldonado-Garcia et al 2016;Paprotny et al 2013;Zielinski et al 2016).…”