Prof. Zheng Hongyu, Shandong University of Technology, China

Title
Investigation of Laser Sintering Copper Nanoparticles on Polymer Substrate for Printed Electronics
Abstract
The presentation will report a feasibility study of laser sintering screen-printed lines from non-conductive Cu nanoparticles on Polyethylene terephthalate (PET) and Polyethylene naphtalate (PEN) polymer films, which are commonly used in the manufacture of functional printed electronics for large-area printing applications. Suitable laser sources and process conditions are identified through characterization of both optical and thermal properties of the materials and substrates. Three types of laser systems were employed, which include direct diode laser (808 nm), Nd:YAG laser (1064 nm & SH 532 nm) and Ytterbium fiber laser (1070 nm). Analysis of the laser sintering mechanisms under different laser wavelengths and process conditions is conducted. The sintering conditions are developed and optimized for each laser system targeting low resistivity and high processing speed. Practical consideration for improving the laser sintering process of Cu nanoparticles are discussed.
Biography
Professor ZHENG obtained his B.Eng from Tsinghua University in 1985 in mechanical engineering and PhD from Imperial College London in 1990 in laser materials processing.  Since 1986, Prof Zheng has been conducting research in laser - material interaction mechanisms, laser micro-/nano-processing, surface texturing and surface modification.  He was a principal scientist and team leader in the Singapore Institute of Manufacturing Technology between 1994 - 2018. During this period, Prof. Zheng led and completed major research projects and industry-oriented projects, some of which have been successfully implemented in industries.  In December 2018, Professor Zheng became a full-time staff in the school of mechanical engineering in Shandong University of Technology (SDUT) in Zibo, and is appointed as the director for the Centre for Advanced Laser Manufacturing (CALM) in SDUT.  Professor Zheng has co-authored more than 160 SCI journal papers with H-index 32.