CYC (Cheng-Ying Chen) Group – Laboratory for Optoelectronic Semiconductors and Energy Conversion
Research Field
Dr. Cheng-Ying (Gary) Chen is an Associate Professor in the Department of Optoelectronics and Materials Technology at National Taiwan Ocean University (NTOU). He received his Ph.D. in Photonics and Optoelectronics from National Taiwan University in 2012, after completing his M.S. in Electrical Engineering at National Tsing Hua University and B.S. in Electrical Engineering at Yuan Ze University. He further broadened his research experience through appointments at Georgia Institute of Technology, UC Berkeley / Lawrence Berkeley National Laboratory, and the Center for Condensed Matter Sciences at National Taiwan University.
Prof. Chen’s research integrates thin-film growth, defect engineering, interface engineering, and operando nano-characterization to develop earth-abundant semiconductors for high-efficiency photovoltaics, photodetectors, photoelectrochemical hydrogen generation, and next-generation optoelectronic devices. His current research includes CZTSSe photovoltaics, Sb₂(S,Se)₃ and related chalcogenide semiconductors, Bi₂O₂Se/Si heterojunction photodetectors, hydrogen-assisted selenization, and synchrotron-based analysis of defect evolution. He currently serves as General Secretary of the 20th Taiwan Vacuum Society and as a Director of the Taiwan Association for Coating and Thin-Film Technology. His recent work on anion-vacancy defect elimination in CZTSe solar cells was shortlisted for the Best Paper Award at the 2025 MRS Spring Meeting.
The CYC Group develops advanced optoelectronic semiconductor materials for photovoltaics, photodetectors, photoelectrochemical hydrogen generation, and next-generation electronic and optoelectronic devices. Our laboratory integrates thin-film synthesis, defect engineering, interface engineering, operando characterization, and device-level analysis to understand and improve material performance from the nanoscale to the device scale.
Current research activities include solution and vacuum-based thin-film growth, sulfurization/selenization processes, structural and optical characterization, synchrotron-based analysis, surface and interface chemistry, carrier transport analysis, and photoelectrochemical measurements. Interns joining the laboratory may participate in sample preparation, materials characterization, data analysis, literature review, scientific discussion, and presentation, depending on their academic background and research skills. Lab/PI’s Website https://sites.google.com/view/cycgroup
1. Earth-abundant thin-film semiconductors for high-efficiency photovoltaics and optoelectronic devices
2. Metal chalcogenide semiconductors, including CZTSSe, Sb₂(S,Se)₃, CdS/Sb₂Se₃, SnS, Cu₂O, Bi₂O₂Se, Ga₂O₃, and transition-metal dichalcogenides
3. Defect engineering, interface engineering, and hydrogen-assisted sulfurization/selenization of semiconductor thin films
4. Operando and synchrotron-based nano-characterization for understanding defect evolution and carrier transport
5. Photoelectrochemical hydrogen generation and semiconductor-based energy conversion
6. Photodetectors, semiconductor heterojunctions, and next-generation electronic/optoelectronic devices
7. Data analysis and computational support for semiconductor materials optimization
Prof. Cheng-Ying (Gary) Chen has received several academic honors and professional recognitions, including the 2022 Taiwan Vacuum Society Young Scholar Award, the Excellent Ph.D. Thesis Award from the Physical Society of the Republic of China, the NSC Graduate Students Study Abroad Program for visiting research at Georgia Tech, and the NSC Postdoctoral Research Abroad Program for postdoctoral research at UC Berkeley / Lawrence Berkeley National Laboratory. He is an Honorary Member of the Phi Tau Phi Scholastic Honor Society of the Republic of China and received the CTCI Foundation Fellowship and Yuan Ze University Scholarship during his academic training.
He currently serves as General Secretary of the 20th Taiwan Vacuum Society and as a Director of the Taiwan Association for Coating and Thin-Film Technology. He has also served as a guest editor for the Journal of Taiwan Vacuum Society, Nanotechnology special issues, and as a Topic Editor for the MDPI topic “Surface and Interface Engineering in Catalytic and Optoelectronic Applications.” His recent work “Anion Vacancy Defect Elimination in CZTSe Solar Cells via Hydrogen-Assisted Selenization—In Operando X-Ray Nanoprobe Analysis” was shortlisted for the Best Paper Award at the 2025 MRS Spring Meeting, Session EN05.03: Thin-Film Compound Semiconductor Photovoltaics. His advisees have also received multiple national and international poster awards, student paper awards, NSTC conference travel grants, and research fellowships.
Ph.D., Graduate Institute of Photonics and Optoelectronics, National Taiwan University, Taiwan, 2012
M.S., Institute of Electrical Engineering, National Tsing Hua University, Taiwan, 2005
B.S., Department of Electrical Engineering, Yuan Ze University, Taiwan, 2003
Additional research experience: Georgia Institute of Technology; UC Berkeley / Lawrence Berkeley National Laboratory; Center for Condensed Matter Sciences, National Taiwan University.
Job Description
Possible internship topics include:
1. Sb₂Se₃ / Sb₂(S,Se)₃ quasi-one-dimensional semiconductor materials for photoelectrochemical hydrogen evolution
2. Bi₂O₂Se, MoS₂, WSe₂, or related 2D / quasi-2D semiconductors for optoelectronic and energy-conversion applications
3. Defect and interface engineering of metal chalcogenide thin films
4. Photoelectrochemical hydrogen evolution reaction (PEC-HER) and semiconductor-based energy conversion
5. Materials characterization and data analysis using XRD, Raman, UV-Vis, SEM, XPS, J–V, EQE, LSV/CV, and Python/MATLAB-based data processing
The internship duration will follow IIPP regulations, generally 28 to 90 days. The final project scope will be adjusted according to the intern’s academic background, available facilities, and the approved internship period.
Lab website:
https://sites.google.com/view/cycgroup
Preferred Intern Educational Level
Senior undergraduate students, Master’s students, or Ph.D. students in Materials Science, Physics, Chemistry, Chemical Engineering, Electrical/Electronic Engineering, Optoelectronics, Energy Engineering, or related fields.
Skill sets or Qualities
Applicants should have a strong interest in semiconductor materials, optoelectronic devices, photoelectrochemical energy conversion, or 2D materials. Basic knowledge of materials science, solid-state physics, chemistry, electrochemistry, or semiconductor devices is preferred. Experience with thin-film processing, hydrothermal synthesis, furnace-based growth, XRD, Raman, UV-Vis, SEM, XPS, electrochemical measurements, or data analysis using Python/MATLAB/Origin is a plus.
The intern should be self-motivated, responsible, willing to learn laboratory techniques, able to communicate in English, follow laboratory safety rules, maintain organized records, and work cooperatively with graduate students and other lab members.