Fabrication and characterization of the piezoelectric microtransformer based on microelectromechanical systems

Abstract

In this letter, the design, fabrication, and characterization of a novel piezoelectric microtransformer with bar geometry are presented. The piezoelectric microtransformers were fabricated using PZT thin films and microelectromechanical system technologies. The dimensions of these devices are 1000×400×5.8μm3 (length×width×thickness). The dynamic displacement of around 9.2±0.064μm was observed at 10Vac. The dynamic displacement varied almost linearly with voltage. When driven at the input voltage of 3Vac, the output voltage of the piezoelectric microtransformer was 6.4Vac at the resonant frequency (Fr), 8.006kHz and load resistance (RL), 1MΩ. The average voltage gain (step-up ratio) was approximately 2.13.

A Survey on Microtransformers

“…Since 2010 the wire bonding technique has been added to the list, although one of the first devices built with this technology appeared in an application bulletin of the Burr-Brown Corporation in 1994 [114]. One of the most versatile processes for building microtransformers with any structure and geometry, is microfabrication [2], [5], [6], [17], [22], [25], [28], [40], [49]- [51], [54], [58], [62], [63], [70], [71], [80], [81], [84], [89], [90], [92], [105], [107]- [109], [122], [128]- [130]. Of course, any of the other fabrication approaches may involve microfabrication in some of the processing steps.…”

A micrometer scale and low temperature PZT thick film MEMS process utilizing an aerosol deposition method

“…Lead-zirconate-titanate (PZT) is a popular piezoelectric material in microelectromechanical systems (MEMS). It has been used in a large variety of micro-device applications, such as micropump [1], micromotor [2], touch probe sensor [3], micropower harvesting [4], and micro-piezoelectric transformer [5,6]. Typical deposition methods of PZT in micromachining include sol-gel coating [7] and sputtering [8].…”

The fabrication of silicon-based PZT microstructures using an aerosol deposition method

“…Lead-zirconate-titanate (PZT) is the most popular piezoelectric ceramic material in micro-electro-mechanical systems (MEMS) because of its high piezoelectric constants. Lots of PZT-based micro-devices have been developed, such as micromotors, micro-transformers, micro-power generators, touch probe sensors and micropumps [1][2][3][4][5][6]. The typical PZT thickness in these devices is smaller than 5 µm, and wet etching is commonly used to pattern the PZT films.…”