Seminar

 ALD Based Synthesis and Applications of Nanomaterials and Other Related Emerging Materials

Hyungjun Kim

School of Electrical and Electronic Engineering, Yonsei University

Recently, the exclusive benefits of atomic layer deposition (ALD), including excellent conformality over nanoscale complex structures, high quality of deposited films even at low temperature down to room temperature, atomic scale thickness controllability, and high uniformity over nanoscale structure, make it viable tool for many emerging applications. Among varous materials which can be prepared by ALD, two dimensional (2D) transition metal dischalcogenides (TMDCs) nanosheets have attracted great attention, since they have exotic electronic and optical properties: Indirect-to-direct bandgap transition depending on the number of layers, high carrier mobility and strong spin-orbit coupling due to their broken inversion symmetry. In contrast to conventional chemical vapor deposition (CVD), ALD makes it a promising synthesis method for 2D TMDCs. In this presentation, I will present the synthesis of various 2D TMDCs nanosheets including MoS₂, WS₂, WSe₂ and their alloys such as Mo_1-xWxS₂ based on ALD process. Also, various appliations of these materials will be presented such as gas sensors and catalysis for hydrogen evolution rate. In addition, ALD for other related materials including other 3D chalcogenides such as GeS, RuS₂ and carbon. Basic growth charateristics and applilcations for ovonic threshold switwching (OTS), Lidar and next generation patterning tehnology will be presented.