Applied Physics Seminar

***Refreshments at 10:45am outside Noyes 153

Abstract:

The critical dimensions of semiconductor devices are continuously shrinking in nanometer and atomic scale with 3D device structure. The demand for dimension control in angstrom level is drastically increasing also in etching processes. Atomic layer etching (ALE) processes are being actively studied and developed for various metals, semiconductor, and dielectric materials. In this talk, plasma processes for atomic layer etching will be discussed for both isotropic and anisotropic patterning of metals and dielectric materials including molybdenum, ruthenium, cobalt, titanium nitride, tantalum nitride, hafnium oxide, zirconium oxides. [1-9] Typical ALE processes consist of surface a modification step and a removal step. For the surface modification, various fluorination, chlorination and oxidation schemes were applied including fluorocarbon deposition, halogenation, oxidation with radicals generated plasmas. For the removal or etching step, various schemes were applied including ion-bombardment, heating, ligand volatilization, ligand exchange, and halogenation. The surface characteristics such as surface roughness and surface residue after plasma-enhanced ALE processes will be also discussed.

1) K. Koh, Y. Kim, C.-K. Kim, H. Chae, J. Vac. Sci. Technol. A, 36(1), 10B106 (2017)

2) Y. Cho, Y. Kim, S. Kim, H. Chae, J. Vac. Sci. Technol. A, 38(2), 022604 (2020)

3) Y. Kim, S. Lee, Y. Cho, S. Kim, H. Chae, J. Vac. Sci. Technol. A, 38(2), 022606 (2020)

4) D. Shim, J. Kim, Y. Kim, H. Chae, J. Vac. Sci. Technol. B., 40(2) 022208 (2022)

5) Y. Lee, Y. Kim, J. Son, H. Chae, J. Vac. Sci. Technol. A., 40(2) 022602 (2022)

6) J. Kim, D. Shim, Y. Kim, H. Chae, J. Vac. Sci. Technol. A., 40(3) 032603 (2022)

7) Y. Kim, H. Chae, Appl. Surf. Sci., 619, 156751 (2023)

8) Y. Kim, H. Chae, Appl. Surf. Sci., 627, 157309 (2023)

9) Y. Kim, H. Chae, ACS. Sustain. Chem. Eng., 11, 6136 (2023)

More about the Speaker:

Heeyeop Chae received his B.S. and M.S. in chemical engineering from Seoul National University and his Ph.D. in chemical engineering from Massachusetts Institute of Technology (MIT). After his Ph.D. he joined Applied Materials, a semiconductor equipment company, in California, USA as a senior process engineer. He has been working as a professor in the School of Chemical Engineering at Sungkyunkwan University (SKKU) since 2004. He is a vice president of Korean Vacuum Society and The Korea Society of Semiconductor and Display Technology. His research interests include i) plasma-enhanced atomic layer etching and deposition, ii) low global warming etching gas development, iii) plasma monitoring and machine learning and iv) light emitting quantum dot materials and devices.