Publications

Yoon Research Group gave two talks at the 65th EMC (Electronic Materials Conference; Santa Barbara, CA; link).

(1) “Photovoltaic Characteristics of PERC-Like CdTe Solar Cells” by E. Roy, K. Powell and H. Yoon.
(2) “Monitoring Stability of Metal-Halide Perovskites Under Combined Stressors of Ion-Beam and Heat” by A. Chowdhury, Y. Hsu, and H. Yoon.

Ashif gave an excellent presentation on his work on perovskite solar cells. He has investigated new technologies to measure the changes in the deterioration of meta-halide perovskites under environmental stressors.

We presented two research works at the PVSC (IEEE 50th Photovoltaic Specialists Conference).

(1) “Impact of Surface Roughness in Measuring Optoelectronic Characteristics of Thin-Film Solar Cells” by D. Magginetti, S. Jeon, Y. Yoon, A. Choudhury, A. Mamun, Y. Qian, J. Gerton, and H. Yoon (IEEE link)

(2) “Design and Fabrication of PERC-Like CdTe Solar Cells Using Micropatterned Al2O3 Layer” by E. Roy, K. Powell, C. Lee, G. Xiong, and H. Yoon (IEEE link)

Our perovskite research in collaboration with U. Toledo (Prof. Yan’s group) and Los Alamos National Lab (Drs. A. Jones and M. Pettes) has been published in the Journal of Physical Chemistry-C.
https://pubs.acs.org/doi/full/10.1021/acs.jpcc.2c09122#

Focused ion beam techniques have been frequently used to section metal-halide perovskites for microstructural investigations. However, the ion beams directly irradiating the sample surface may alter its properties far different from those of pristine, potentially leading to modified deterioration mechanisms under aging stressors. Read more

We present a newly developed microcontact approach at the 49th IEEE Photovoltaic Specialists Conference. This approach allows the local transport measurements across individual grains and grain boundaries.

Thank you for your efforts in this project, mainly former members (David Magginetti and Kaden Powell), Yu-Lin, and Etee. We also thank our collaborators (First Solar, NREL) and the funding agencies (NSF, DOE).

A journal paper with Korea Aerospace University, Los Alamos National Lab, and other collaborators has been published. In this work, a high-resolution Kelvin probe force microscopy (KPFM) was used to study the heterogeneous electronic properties of 2D/3D materials (Ge film on MoS2). See the details here: https://aip.scitation.org/doi/full/10.1063/5.0075599.

A first-year graduate student, Yu-Lin (Nick) Hsu, won a Student Award at M&M (Microscopy and Microanalysis Conference; https://www.microscopy.org/MandM/2021/). We also congratulate our former graduate student, Kaden Powell, who had initiated this work.

Their project focuses on hybrid metal-halide perovskite solar cells. M&M is the largest international microscopy conference, often having over 1600 attendees. We are so proud of them. We thank our collaborators (Dr. Chongwen Li, Prof. Yanfa Yan at University of Toledo).

• MSA site: https://www.microscopy.org/awards/onsiteawards.cfm
• ECE News: https://www.ece.utah.edu/2021/08/12/ece-students-awarded-for-research-poster/

This work was supported by the U.S. Department of Energy under the DE-FOA-0002064 program award number DE-EE0008985 and the National Science Foundation (NSF CAREER 5850323).

Dr. Yoon is invited to give a talk at the Advanced Photonics Congress (OSA, The Optical Society) in July, 2021. She will discuss the recent progress on the “Nanocontact Approach” for thin-film photovoltaic materials and devices (CdTe, perovskites).

Kaden and Nick gave a presentation at the Electronic Materials Conference (EMC). The EMC was held online owing to the COVID situation. Thank you for your work.

Yang/David’s paper is online now (Scientific Reports). Thank you for their dedication. We also thank to our collaborators.

Yang Qian, David J. Magginetti, Seokmin Jeon, Yohan Yoon, Tony L. Olsen, Maoji Wang, Jordan M. Gerton & Heayoung P. Yoon, “Heterogeneous optoelectronic characteristics of Si micropillar arrays fabricated by metal-assisted chemical etching”, Scientific Reports 10, 16349 (2020)

https://www.nature.com/articles/s41598-020-73445-x

Kaden’s first paper has been published. Congratulations!

Powell, K.M., Yoon, H.P., “Depth-dependent EBIC microscopy of radial-junction Si micropillar arrays”, Appl. Microsc. 50, 17 (2020).

https://doi.org/10.1186/s42649-020-00037-4 (here)