SUBJECT: Ph.D. Proposal Presentation
BY: Ji Hyeon Song
TIME: Monday, October 15, 2018, 8:00 a.m.
PLACE: MARC Building, 201
TITLE: A Nanoparticle Laser Patterning Process to Fabricate Flexible Electronics
COMMITTEE: Dr. Yan Wang, Co-Chair (ME, GT)
Dr. Sung-Hoon Ahn, Co-Chair (MAE, SNU)
Dr. Shreyes Melkote (ME, GT)
Dr. Suresh Sitaraman (ME, GT)
Dr. Seung Hwan Ko (MAE, SNU)
Dr. Doo-Man Chun (ME, Ulsan Univ.)


Flexible electronics are attractive for new applications because of their flexible forms as well as properties of light weight and portability. The circuits are usually printed on flexible substrates such as plastic, fabric, and paper, which are delicate and heat sensitive. Traditional photolithography with the use of high temperature and corrosive chemicals is not suitable for flexible substrates. The fabrication of flexible electronics requires fast and low temperature printing processes in order to minimize the damage of the flexible substrates. In this research, a high-throughput nanoparticle laser patterning (NLP) process for flexible electronics is developed, where nanoparticles are sintered with laser while they are selectively deposited. Copper and silver particles are successfully deposited on paper and PET substrates. To characterize the thermal effect of laser, chemical composition of particles is analyzed using X-ray diffractometer. Electromechanical property is also analyzed for the purpose of sensing applications. It is shown that the property is sensitive to the porosity difference caused by different levels of laser irradiation. The deposition mechanisms are modeled with an analytical model as well as molecular dynamics and kinetic Monte Carlo simulations. The developed process can be used to fabricate patterns on flexible substrates such as hydrophobic and hydrophilic surfaces with controlled oxidation levels, and flexible and foldable electronics on papers. The use of low laser power and low aerosol pressure makes NLP a low-cost process for large-area deposition.

Location online: Bluejeans meeting (, Meeting ID (Meeting ID: 197035268)