Insights into FinFET Structure Collapse: A Reactive Force Field-Based Molecular Dynamics Investigation

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Abstract:

As miniaturization progresses, pattern collapse during the drying step of wet cleaning processes has become a critical issue in the semiconductor industry. In this study, we used reactive molecular dynamics simulations to analyze pattern collapse, with a focus on bondings and reactions. To simulate pattern deformation during the drying process of wet cleaning, we created a FinFET model as a HAR structure. The surface of this model was terminated with hydrogen atoms. The widths between the patterns were changed in order to create a Laplace pressure difference when water molecules were placed on the surface. The model was simulated by placing water molecules up to half the height of the pattern. As a result, the pattern was deformed. Furthermore, by removing water molecules and changing the Laplace pressure balance, it was found that the pattern contacted each other at the tip. The pattern remained in contact when water molecules were removed from the model. In the contact area, the covalent bonds, such as Si-Si and Si-O-Si, were not formed, but instead, hydrogen-to-hydrogen van der Waals bonds were formed between patterns. We calculated the total van der Waals forces between hydrogen atoms at the contact surfaces using the Hamaker equation and calculated the elastic force of the patterns using the beam deflection formula. Our calculations showed that the total van der Waals forces between hydrogen atoms at the contact surfaces were larger than the elastic force of the patterns, indicating that van der Waals forces could be a factor in maintaining the contact of the patterns.

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Solid State Phenomena (Volume 346)

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123-128

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August 2023

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© 2023 Trans Tech Publications Ltd. All Rights Reserved

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[1] N. Vrancken et al., "Nanoscale Elastocapillary Effect Induced by Thin-Liquid-Film Instability", The Journal of Physical Chemistry Letters, vol. 11, no. 7, pp.2751-2758, 2020/04/02 2020.

DOI: 10.1021/acs.jpclett.0c00218

Google Scholar

[2] Y. Sasaki, T. Yamazaki, and Y. Kimura, "Liquid-Cell Transmission Electron Microscopy Observation of Two-Step Collapse Dynamics of Silicon Nanopillars on Evaporation of Propan-2-ol: Implications for Semiconductor Integration Density", ACS Applied Nano Materials, vol. 5, no. 7, pp.9495-9502, 2022/07/22 2022.

DOI: 10.1021/acsanm.2c01744

Google Scholar

[3] D. W. Bassett, "(Invited) Capillary Pattern Collapse: Prediction and Prevention from Past to Future," ECS Transactions, vol. 92, no. 2, p.95, 2019/07/03 2019.

DOI: 10.1149/09202.0095ecst

Google Scholar

[4] M. Otsuji, T. Tanaka, A. Iwasaki, H. Takahashi, and Y. Okuno, "Extendibility Study of Conventional IPA Drying Process From Dynamic Fluid Model for Pattern Collapse", ECS Transactions, vol. 108, no. 4, p.145, 2022/05/20 2022.

DOI: 10.1149/10804.0145ecst

Google Scholar

[5] D. S. L. Mui, N. Musselwhite, and M. Kawaguchi, "Factors Influencing Drying Induced Pattern Collapse", Solid State Phenomena, vol. 282, pp.

DOI: 10.4028/www.scientific.net/ssp.282.201

Google Scholar

[6] T. Koide et al., "Effect of Surface Energy Reduction for Nano-Structure Stiction", ECS Transactions, vol. 69, no. 8, p.131, 2015/09/11 2015.

DOI: 10.1149/06908.0131ecst

Google Scholar

[7] A. C. T. van Duin, S. Dasgupta, F. Lorant, and W. A. Goddard, "ReaxFF:  A Reactive Force Field for Hydrocarbons", The Journal of Physical Chemistry A, vol. 105, no. 41, pp.9396-9409, 2001/10/01 2001.

DOI: 10.1021/jp004368u

Google Scholar

[8] S. Uehara, Y. Wang, Y. Ootani, N. Ozawa, and M. Kubo, "Molecular-Level Elucidation of a Fracture Process in Slide-Ring Gels via Coarse-Grained Molecular Dynamics Simulations", Macromolecules, vol. 55, no. 6, pp.1946-1956, 2022/03/22 2022.

DOI: 10.1021/acs.macromol.1c01981

Google Scholar

[9] A. K. Rappe and W. A. Goddard, III, "Charge equilibration for molecular dynamics simulations", The Journal of Physical Chemistry, vol. 95, no. 8, pp.3358-3363, 1991/04/01 1991.

DOI: 10.1021/j100161a070

Google Scholar

[10] J. Yeon and A. C. T. van Duin, "ReaxFF Molecular Dynamics Simulations of Hydroxylation Kinetics for Amorphous and Nano-Silica Structure, and Its Relations with Atomic Strain Energy", The Journal of Physical Chemistry C, vol. 120, no. 1, pp.305-317, 2016/01/14 2016.

DOI: 10.1021/acs.jpcc.5b09784

Google Scholar

[11] D. J. Evans and B. L. Holian, "The Nose–Hoover thermostat", The Journal of Chemical Physics, vol. 83, no. 8, pp.4069-4074, 1985/10/15 1985.

DOI: 10.1063/1.449071

Google Scholar

[12] T. Tanaka, M. M. Mitsuaki Morigami, and N. A. Nobufumi Atoda, "Mechanism of Resist Pattern Collapse during Development Process", Japanese Journal of Applied Physics, vol. 32, no. 12S, p.6059, 1993/12/01 1993.

DOI: 10.1143/JJAP.32.6059

Google Scholar

[13] H. C. Hamaker, "The London—van der Waals attraction between spherical particles", Physica, vol. 4, no. 10, pp.1058-1072, 1937/10/01/ 1937.

DOI: 10.1016/S0031-8914(37)80203-7

Google Scholar

[14] C. J. Tsai, D. Y. H. Pui, and B. Y. H. Liu, "Elastic Flattening and Particle Adhesion", Aerosol Science and Technology, vol. 15, no. 4, pp.239-255, 1991/01/01 1991.

DOI: 10.1080/02786829108959531

Google Scholar