[26a-P03-1~15] 8 Plasma Electronics(Poster)

▲ [26a-P03-11] Decomposition and adsorption mechanisms of chlorosilanes and methylchlorosilanes on Si(100) surface

〇(D)Jomar Unico Tercero¹, Michiro Isobe¹, Tomoko Ito¹, Kazuhiro Karahashi¹, Satoshi Hamaguchi¹ (1.Osaka Univ.)

Keywords:atomic layer deposition, density functional theory, molecular dynamics simulations

Atomic layer deposition (ALD) is a technique that has been widely used in the atomic-scale fabrication of semiconductor devices since it offers a thin-layer deposition of a material one at a time for highly uniform and accurate deposition. As such, it has been used extensively for various materials, including silicon nitride (SiN) [1]. To proceed with the deposition, Si and Cl containing precursors need to be carefully chosen for the adsorption half-cycle of ALD, where Cl is needed for self-limiting adsorption. For a better selection of precursor gases, a better understanding of the interaction of precursor molecules with a Si surface is needed[2-3]. In this study, the reaction mechanisms of chlorosilanes (SiH_xCl_4-x) and methylchorosilanes (Si(CH₃)_xCl_4-x) on the Si(100):2x1 surface were examined with density functional theory (DFT) calculations and classical molecular dynamics (MD) simulation. The DFT evaluation of the adsorption energies, activation barriers, and the transition structures of the precursor gases adsorbed on the Si surface has shown that the adsorption energy typically increases as the chlorine (Cl) substitution increases. The sticking probabilities of gaseous species and chemical compositions of precursor-adsorbed surfaces were also determined with MD simulations.
References
[1] X. Meng, Y. Byun, H. S. Kim, J. S. Lee, A. T. Lucero, L. Cheng, and J. Kim, Materials (Basel), 9, 1007 (2016).
[2] M.A Hall, C. Mui, C.B. Musgrave, J. Phys. Chem. B 105, 12068–12075 (2001).
[3] S. Yadav, C.V. Singh, Applied Surface Science 475, 124-134 (2019).