Micro & Nano Systems Laboratory at Yeungnam University

We focus on the development of MEMS devices and systems. Our work in 'MEMS Devices' includes the design and fabrication of micro/nano-scale electronic and mechanical devices such as sensors, transducers, electrodes, and energy harvesters. We utilize a diverse array of high-performance functional materials to achieve these goals. Our 'Systems' research involves creating prototypes that integrate various mechanical and electronic components with signal processors and packaging. These systems are geared towards applications in industries such as semiconductors, robotics, and medical devices. Furthermore, we conduct reliability studies to analyze the stability and lifespan of MEMS devices and systems under varying environmental conditions. 

Through these efforts, we aim to maximize not only the academic value but also the industrial applicability of our systems, thereby enhancing their practical significance.

1. Piezoelectric acoustic devices based on aluminum nitride thin film

Piezoelectric aluminum nitride (AlN) thin film is a key material for semiconductor devices including ultrasonic transducers, microphones, and touch/force/acceleration sensors. My research will be focused on developing high-performance semiconductor devices with enhanced piezoelectricity of the AlN thin film with (002) highly oriented crystal structure by the sputtering process. The semiconductor devices based on the piezo-MEMS can be integrated with signal processing circuits and potentially applied to the smart microphone, hearing aid, and physical sensing system.

Selected Publications on this topic: 

(1) Microsyst. Nanoeng., 8, 22, (2022), (2) Adv. Healthc. Mater., 5, 2481 (2016) (3) Adv. Healthc. Mater., 6, 1700674 (2017)

(4) J. Micromech. Microeng., 27, 075006 (2017) (5) Sci. Rep., 5, 12447, (2015) 

2. Self-powered IoT sensor system based on high-performance functional materials

Prof. Jongmoon Jang’s group has been studied to improve the performance of the piezoelectric single crystal through defect engineering (Mechanical quality factor & piezoelectric constant). The bulk piezoelectric single crystals will be thinned by a grinding and polishing process to be compatible with the semiconductor fabrication process to develop miniaturized energy harvesters/sensors in mm-scale. I will also focus on developing reliable energy harvesters/IoT sensors, which include lifetime assessment, estimation, and various environmental factors. The high-performance energy harvesters will be key technologies to drive the self-powered multiple functional IoT sensors for environmental monitoring systems.

Selected Publications on this topic: 

(1) Nano Energy, 114, 108645, (2023) (2) J. Mater. Chem A, 11, 3364 (2023)             (3) ACS Nano, 16, 15328 (2022)

(4) Nano Energy, 101, 107567 (2022)         (5) Adv. Func. Mat., 32, 2112028 (2022)

3. Biomedical devices based on advanced semiconductor process

Prof. Jang's group focuses on additive manufacturing to develop functional 3D MEMS devices for biomedical applications. The biocompatible, steroid-containing 3D micro/nanodevices can be developed by applying two-photon polymerization (2PP) micro/nano 3D printing or drop-on-demand inkjet printing (DoD-IJP) technique, which could be potentially applied to develop next-generation medical devices/systems such as a cochlear implant, cardiac artificial pacemaker, and stent.

Selected Publications on this topic:

(1) Adv. Healthc. Mater., 8, 1900379, (2019)                  (2) Ceram. Int., 47, 7593 (2021)

(3) ACS Appl. Mater. Inter., 12, 17244 (2020)   (4) Acta Otolaryngol. 140, 705 (2020)