Contour-Mode Ring-Shaped AlN Microresonator on Si and Feasibility of Its Application in Series-Resonant Converter

Abstract

Microelectromechanicalsystems (MEMS) resonators on Si have the potential to replace the discrete passive components in a power converter. The main intention of this paper is to present a ring-shaped aluminum nitride (AlN) piezoelectric micro-resonator that can be used as an energytransferring device to replace inductors/capacitors in low power resonant converters for biomedical applications. Finite element simulation results have been provided, showing the mode of vibration at resonant frequency. The zero voltage switching (ZVS) condition for a series resonant converter incorporating the proposed MEMS resonator has been presented analytically and verified through experiment. This ZVS condition can be found in terms of the equivalent circuit parameters of the resonator. To the knowledge of the authors, ZVS analysis based on the equivalent electrical circuit model of the thin piezoelectric film resonators has not yet been reported in the literature. A CMOS-compatible fabrication process has beenproposed and implemented. In addition, the fabricated devices have been characterized and experimental results are included in the paper. The first contour mode AlN MEMS resonator with moderately low resonant frequency and motional resistance is reported in this paper with measured resonant frequency and motional resistance of 87.28 MHz and 36.728 Ω respectively.

A Comprehensive Review on Rectifiers, Linear Regulators, and Switched-Mode Power Processing Techniques for Biomedical Sensors and Implants Utilizing in-Body Energy Harvesting and External Power Delivery

“…In this way, the VCR of the converters can be controlled very precisely as opposed to switched capacitor-based converters. During the last 10 years, the co-authors of this manuscript have proposed a resonator-based power conversion architecture that can achieve high VCR without using inductors [194]- [196]. This type of "system-on-chip" solutions are still in their infancy, and extensive research is needed to come up with a universal solution that could be implanted without any EMI or MRI issues.…”

Harder and Denser AlN-TiB₂ Ceramic Composites Processed by Spark Plasma Sintering

“…2. It is also worth mentioning, that TiN may also be formed by the direct reaction between the precursors: AlN + TiB 2 → AlB 2 + TiN (3) in which the AlB 2 compound would also be formed and incorpored into the composite structure, Fig. 2, at all sintering temperatures.…”

“…This unique thermal and mechanical properties exhibited by AlN earned its numerous applications in electronics, automotive, defense and aerospace industries [2]. In particular, AlN films have been extensively applied as microelectronics materials in micro-electrical-mechanical systems (MEMS) [3,4], high temperature exhausting sensor [5], solar collector [6], light emitting diode (LED) [7], just to mention few examples. As bulk composites, AlN is being combined with copper [8], aluminum alloy [9], borosilicate [10] and steel [11].…”