Thin Film Synthesis at the Atomic Scale

Key pieces of modern day electronic device technology keep following the trend of down-scaling. Thin film deposition has become of great importance in the semiconductor industry as critical device dimensions have reached the nanometer scale. As down-scaling continues rapidly, device features approach fundamental physical limits. During my doctoral research (at the University of Vienna and Stanford University) my work’s focus was on the characterization of thin films for new high-efficiency applications in solar cells and next-generation dielectrics. The experimental work was particularly focused on atomic layer deposition (ALD), which is a key enabling technique to synthesize high-quality thin films with precise thickness control down to the Angstrom level while staying at low processing temperatures. Unlike in conventional chemical vapor deposition techniques (where there is a continuous flow of precursor gas) in ALD the precursors are introduced sequentially until saturation of the precursor reaction with the surface has occurred and the by-products and remaining precursors are purged out. The key feature that enables this high-quality, conformal growth is the self-limiting nature of the individual half-steps, as illustrated below for the growth of aluminum oxide with the tri-methyl-aluminum (TMA) precursor. Due to the cycle-based nature of this deposition technique thin films can be grown with thickness control down to the atomic level.

ALD cycle illustration

During plasma-enhanced ALD (PEALD) a more reactive plasma is used as an oxidant which facilitates lower processing temperatures and higher film quality. However, PEALD typically exhibits less conformal growth of films deposited on complex 3-dimensional substrates with high aspect ratios. My research established processes to deposit thin dielectric films with a record-breaking high dielectric constant and high conformality on complex, high aspect-ratio substrates using PEALD. These metrics are crucial for dynamic RAM applications and resulted in multiple publications and patents with our industrial collaborators. A list of relevant publications with further details are listed below. The list includes my ALD-related work for applications in dielectrics, solar cells, low etching-rate spacer materials, sensors, and catalysis.

ALD cycle illustration

Selected Publications

  • ACS Applied Materials & Interfaces, 11, 9 (2019) 9594–9599 10.1021/acsami.8b21054

    Electrical Properties of Ultrathin Platinum films by Plasma Enhanced Atomic Layer Deposition

    H. J. K. Kim, K. E. Kaplan, P. Schindler, S. Xu, M. M. Winterkorn, D. B. Heinz, T. S. English, J Provine, F. B. Prinz, and T. W. Kenny

  • Nature Catalysis, 1 (2018) 624–630 10.1038/s41929-018-0118-1

    Extending the Limits of Pt/C Catalysts with Passivation-Gas-Incorporated Atomic Layer Deposition

    S. Xu, Y. Kim, J. Park, D. Higgins, S.-J. Shen, P. Schindler, D. Thian, J Provine, J. Torgersen, T. Graf, T. Schladt, M. Orazov, B. Liu, T. Jaramillo, and F. B. Prinz

  • Scripta Materialia, 111 (2016) 106–109 10.1016/j.scriptamat.2015.08.026

    Plasma-Enhanced Atomic Layer Deposition of BaTiO3

    P. Schindler*, Y. Kim*, D. Thian, J. An, and F. B. Prinz

  • ACS Applied Materials & Interfaces, 8, 27 (2016) 17599–17605 10.1021/acsami.6b03194

    Plasma Enhanced Atomic Layer Deposition of SiN-AlN Nanolaminates for Ultra Low Wet Etch Rate in Hydrofluoric Acid

    Y. Kim, J Provine, S. P. Walch, J. Park, W. Phuthong, A. L. Dadlani, H. J. Kim, P. Schindler, K. Kim, and F. B. Prinz

  • AIP Advances, 6, 6 (2016) 065012 10.1063/1.4954238

    Correlation of Film Density and Wet Etch Rate in Hydrofluoric Acid in Plasma Enhanced Atomic Layer Deposition of Silicon Nitride

    J Provine, P. Schindler, Y. Kim, S. P. Walch, H. J. Kim, K. H. Kim, and F. B. Prinz

  • Acta Materialia, 117 (2016) 153–159 10.1016/j.actamat.2016.07.018

    Plasma-Enhanced Atomic Layer Deposition of Al-Doped Barium Titanate

    Y. Kim, P. Schindler, A. L. Dadlani, S. Acharya, J Provine, J. An, and F. B. Prinz

  • Journal of Vacuum Science & Technology A, 34 (2016) 01A138 10.1116/1.4937991

    Molecular Oxygen Reactions with Tetrakisdimethylamido-metal Precursors for Atomic Layer Deposition

    J Provine*, P. Schindler*, J. Torgersen, H. J. Kim, H. P. Karnthaler, and F. B. Prinz

  • Journal of Materials Chemistry C, 4 (2016) 1945–1952 10.1039/c5tc03561a

    Atomic Layer Deposition of Barium Oxide and high-k Barium Titanate Thin Films using Novel Pyrrole Based Precursor

    S. Acharya*, J. Torgersen*, Y. Kim, J. Park, P. Schindler, A. L. Dadlani, M. Winterkorn, S. Xu, S. Walch, T. Usui, C. Schildknecht, and F. B. Prinz

  • ACS Langmuir, 31, 18 (2015) 5057–5062 10.1021/acs.langmuir.5b00216

    Enhanced Step Coverage of TiO2 Deposited on High Aspect Ratio Surfaces by Plasma-Enhanced Atomic Layer Deposition

    P. Schindler, M. Logar, J Provine, and F. B. Prinz

  • Journal of Materials Chemistry C, 3 (2015) 12192–12198 10.1039/C5TC02912K

    Exploring Local Electronic Structure and Geometric Arrangement of ALD Zn(O,S) Buffer Layers using X-Ray Absorption Spectroscopy

    A. L. Dadlani*, O. Trejo*, S. Acharya*, J. Torgersen, I. Petousis, D. Nordlund, R. Sarangi, P. Schindler, and F. B. Prinz

    * contributed equally

Collaborators / Advisors