I. Printed Electronics: Material design, processing, and integration
Our group is focusing on developing completely new of methods and solutions in printing technology in terms of materials, processing, and integration. In particular, printed inorganic semiconductor-based electrical devices have unique electrical, optical, and mechanical performance and have received significant attention in display backplane and hybrid manufacturing process regarding the cost issue and the new form factor of flexible technology. Furthermore, printed resistors, capacitors, inductors, and simple logic devices have been considered very recently.
Our group pursues the invention of easily-processible materials based on new chemical approaches at low temperatures. In particular, ink-jet printing, such as selective deposition, is highly sensitive to the formation shape and electrical properties that are caused by droplet volume, surface energy of the substrate, baking time and temperatures. Controlling surface morphology, viscosity, and chemical reaction time are critical issues of high-quality films, and they are issues that we address.
II. Bioelectronics: Neuro sensing platform beyond physiological interferences
Our group is exploring the development of printed, universal neurochip that has the arrays of multi-functional measurements, e.g., brain pressure in cerebrospinal fluid, interneuronal signals, and electrical activity at the time scale. Recently, our group developed new quasi-2D metal oxides and sensor platforms by using a simple and straightforward printing technology. Our group is considering material properties, such as degradation, defects, grain boundaries, chemical compositions, and thickness dependency of quasi-2D metal oxides for high sensitivity and reliability. We pursues the following fundamental challenges of sensor mechanism correlated with materials properties, i.e., (i) overcoming electrostatic screening in high ionic strength for practical applications; (ii) creating a physics model for the interpretation of biomolecule/sensing surface interactions; and (iii) exploring stable and accurate sensing methodologies in physiologically relevant ionic strength solutions. The focus will be on understanding the neurochemical function of the healthy brain in relation to complex behaviors and corresponding dysfunction in psychiatric and neurodegenerative disorders to ultimately identify new therapeutic targets for these diseases.
III. Wearable/implantable multi-functional sensors
Based on the development of biosensors enabling physiological environments, our group is trying to develop wearable/implantable healthcare biosensor platforms in terms of human vital monitoring system and instant therapy of edema, inflammation, and wounds, such as the treatment of the trauma to the body. Several indicative examples of research directions that our group intends to pursue are as follows: (i) focusing on free form factors of interconnects, responsive materials, and substrates for highly flexible devices to the human body; (ii) expanding this topic to wireless communication to connect anywhere, anytime between the human body and big data analyzing for real-time health diagnosis; (iii) developing lightweight devices that are comfortable on the skin with long-term attachment; and (iv) developing biodegradable and permanent bio-compatible materials and device structures for implantable biosensors. This broad-scale research effort requires interdisciplinary approaches to materials science, chemistry, biology, computer science, electrical engineering, and mechanical engineering together.
IV. Ultra-Wide bandgap semiconductors for power applications
Our group is exploring new class of ultra-wide bandgap (UWB) semiconductors, which beta-gallium oxide has an extremely wide bandgap of 4.8eV that dwarfs silicon's 1.1eV and exceeds the 3.3eV exhibited by SiC and GaN. The difference gives β-Ga2O3 the ability to withstand a larger electric field than silicon, SiC and GaN can without breaking down. Furthermore, β-Ga2O3 handles the same amount of voltage over a shorter distance. This makes it invaluable for producing smaller, more efficient high-power transistors. The most promising application might be as high-voltage rectifiers in power conditioning and distribution systems such as electric cars and photovoltaic solar systems.
V. Neuromorphic synapse devices for the recognition of multidimensional unstructured information
Artificial intelligence (AI) has the ability of revolutionizing our lives and society in a radical way, by enabling machine learning in the industry, business, health, transportation, and many other fields. The ability to recognize objects, faces, and speech, requires, however, exceptional computational power and time, which is conflicting with the current difficulties in transistor scaling due to physical and architectural limitations. To overcome this issue, our group is exploring new materials and device systems using electric, photonics, and bionic stimulation for the recognition and learning of multidimensional instructed information.
VI. Granted Project
1. "프린팅 기반 초단막 고민감성 산화물 센서플랫폼 연구", 신입교원지원사업, 교내연구지원사업, 1,000 만원 (2016.10 ~ 2018.01) / 연구책임자
2. "프린팅 기반 준-2차원 산화물반도체/압타머 범용 플랫폼 기초 연구", 이공학개인기초연구지원사업, 교육부, 5,000만원 (2017.06 ~ 2020. 05) / 연구책임자
3. "4H-SiC SBD edge termination 성능 개선을 위한 산화막 애칭 공정 기술", 맞춤형기술파트너지원사업, 중소기업청, 3,000만원 (2017.07 ~ 2018.01) / 연구책임자
4. "패치형 웨어러블 실시간 건강모니터링 센서", 대학기술경영촉진사업 시작품 제작지원, KIAT, 4,000만원 (2017.07 ~ 2018.05) / 연구책임자
5. "ß-Ga2O3 인터페이스 제어 기반 Power MOSFET 소자 기초 연구", 산학프로젝트, (주)현대자동차, 10,000만원 (2019.08 ~ 2021. 2) / 연구책임자
6. "차세대 전력반도체 소자제조 인력양성 사업", 한국산업기술진흥원, 153,000만원 (2020.03 ~ 2025.02) / 연구책임자
7. "다차원 비정형 정보 인지 및 학습이 가능한 뉴로모픽 시냅스 소자 개발 및 응용", 중견연구자지원사업, 한국연구재단, 50,000만원 (2020.03 ~ 2025.02) / 연구책임자