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Engineering metal oxidation using epitaxial strain

Nature Nanotechnology volume 18, pages 1005–1011 (2023)Cite this article

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Abstract

The oxides of platinum group metals are promising for future electronics and spintronics due to the delicate interplay of spin-orbit coupling and electron correlation energies. However, their synthesis as thin films remains challenging due to their low vapour pressures and low oxidation potentials. Here we show how epitaxial strain can be used as a control knob to enhance metal oxidation. Using Ir as an example, we demonstrate the use of epitaxial strain in engineering its oxidation chemistry, enabling phase-pure Ir or IrO2 films despite using identical growth conditions. The observations are explained using a density-functional-theory-based modified formation enthalpy framework, which highlights the important role of metal-substrate epitaxial strain in governing the oxide formation enthalpy. We also validate the generality of this principle by demonstrating epitaxial strain effect on Ru oxidation. The IrO2 films studied in our work further revealed quantum oscillations, attesting to the excellent film quality. The epitaxial strain approach we present could enable growth of oxide films of hard-to-oxidize elements using strain engineering.

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Fig. 1: Surface Ir metal formation with increasing film thickness.
Fig. 2: Varying thickness-dependent structural evolution as a function of epitaxial strain.
Fig. 3: Microstructure of 26 nm IrO2 (001) using SEM, STEM and elemental EDX mapping.
Fig. 4: Effect of oxygen pressure on strain-relaxation mechanism.
Fig. 5: DFT calculations of formation enthalpy as a function of epitaxial strain.

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Data availability

The source data for the results of this work can be accessed using the given link: https://doi.org/10.13020/9wm7-x981. Any additional data related to this paper may be requested from the corresponding authors.

References

  1. Novotny, Z. et al. Kinetics of the thermal oxidation of Ir(100) toward IrO2 studied by ambient-pressure X-ray photoelectron spectroscopy. J. Phys. Chem. Lett. 11, 3601–3607 (2020).

    Article  Google Scholar 

  2. van Spronsen, M. A., Frenken, J. W. M. & Groot, I. M. N. Observing the oxidation of platinum. Nat. Commun. 8, 429 (2017).

    Article  Google Scholar 

  3. Nunn, W. et al. Novel synthesis approach for “stubborn” metals and metal oxides. Proc. Natl Acad. Sci. USA 118, e2105713118 (2021).

    Article  CAS  Google Scholar 

  4. Liu, X. R. et al. Synthesis and electronic properties of Ruddlesden–Popper strontium iridate epitaxial thin films stabilized by control of growth kinetics. Phys. Rev. Mater. 1, 075004 (2017).

    Article  Google Scholar 

  5. Nair, H. P. et al. Demystifying the growth of superconducting Sr2RuO4 thin films. APL Mater. 6, 101108 (2018).

    Article  Google Scholar 

  6. Nunn, W. et al. Solid-source metal-organic molecular beam epitaxy of epitaxial RuO2. APL Mater. 9, 091112 (2021).

    Article  CAS  Google Scholar 

  7. Wakabayashi, Y. K. et al. Machine-learning-assisted thin-film growth: Bayesian optimization in molecular beam epitaxy of SrRuO3 thin films.APL Mater. 7, 101114 (2019).

    Article  Google Scholar 

  8. Kim, B. J. et al. Phase-sensitive observation of a spin-orbital Mott state in Sr2IrO4. Science 323, 1329–1332 (2009).

    Article  CAS  Google Scholar 

  9. Kim, W. J. et al. Strain engineering of the magnetic multipole moments and anomalous Hall effect in pyrochlore iridate thin films.Sci. Adv. 6, eabb1539 (2020).

    Article  CAS  Google Scholar 

  10. Kim, Y. K., Sung, N. H., Denlinger, J. D. & Kim, B. J. Observation of a d-wave gap in electron-doped Sr2IrO4. Nat. Phys. 12, 37–41 (2016).

    Article  CAS  Google Scholar 

  11. Kushwaha, P. et al. Nearly free electrons in a 5d delafossite oxide metal. Sci. Adv. 1, e1500692 (2015).

    Article  Google Scholar 

  12. Nelson, J. N. et al. Interfacial charge transfer and persistent metallicity of ultrathin SrIrO3/SrRuO3 heterostructures. Sci. Adv. 8, eabj0481 (2022).

    Article  CAS  Google Scholar 

  13. Zhu, Z. H. et al. Anomalous antiferromagnetism in metallic RuO2 determined by resonant X-ray scattering. Phys. Rev. Lett. 122, 017202 (2019).

    Article  CAS  Google Scholar 

  14. Uchida, M. et al. Field-direction control of the type of charge carriers in nonsymmorphic IrO2. Phys. Rev. B 91, 241119 (2015).

    Article  Google Scholar 

  15. Smejkal, L., Gonzalez-Hernandez, R., Jungwirth, T. & Sinova, J. Crystal time-reversal symmetry breaking and spontaneous Hall effect in collinear antiferromagnets. Sci. Adv. 6, eaaz8809 (2020).

    Article  CAS  Google Scholar 

  16. Nelson, J. N. et al. Dirac nodal lines protected against spin-orbit interaction in IrO2. Phys. Rev. Mater. 3, 064205 (2019).

    Article  CAS  Google Scholar 

  17. Ruf, J. P. et al. Strain-stabilized superconductivity. Nat. Commun. 12, 59 (2021).

    Article  CAS  Google Scholar 

  18. Ellingham, H. J. T. Reducibility of oxides and sulphides in metallurgical processes. J. Soc. Chem. Ind. Trans. Commun. 63, 125–160 (1944).

    CAS  Google Scholar 

  19. Chambers, S. A. Epitaxial growth and properties of thin film oxides. Surf. Sci. Rep. 39, 105–180 (2000).

    Article  CAS  Google Scholar 

  20. Prakash, A. et al. Hybrid molecular beam epitaxy for the growth of stoichiometric BaSnO3. J. Vac. Sci. Technol. A 33, 060608 (2015).

    Article  Google Scholar 

  21. Schlom, D. G. Perspective: oxide molecular-beam epitaxy rocks!. APL Mater. 3, 062403 (2015).

    Article  Google Scholar 

  22. Smith, E. H. et al. Exploiting kinetics and thermodynamics to grow phase-pure complex oxides by molecular-beam epitaxy under continuous codeposition. Phys. Rev. Mater. 1, 023403 (2017).

    Article  Google Scholar 

  23. Song, J. H., Susaki, T. & Hwang, H. Y. Enhanced thermodynamic stability of epitaxial oxide thin films. Adv. Mater. 20, 2528–252 (2008).

    Article  CAS  Google Scholar 

  24. Petrie, J. R. et al. Strain control of oxygen vacancies in epitaxial strontium cobaltite films. Adv. Funct. Mater. 26, 1564–1570 (2016).

    Article  CAS  Google Scholar 

  25. Yun, H., Prakash, A., Birol, T., Jalan, B. & Mkhoyan, K. A. Dopant segregation inside and outside dislocation cores in perovskite BaSnO3 and reconstruction of the local atomic and electronic structures. Nano Lett. 21, 4357–4364 (2021).

    Article  CAS  Google Scholar 

  26. Gorbenko, O. Y., Samoilenkov, S. V., Graboy, I. E. & Kaul, A. R. Epitaxial stabilization of oxides in thin films. Chem. Mater. 14, 4026–4043 (2002).

    Article  CAS  Google Scholar 

  27. Truttmann, T. K., Liu, F. D., Garcia-Barriocanal, J., James, R. D. & Jalan, B. Strain relaxation via phase transformation in high-mobility SrSnO3 films. ACS Appl. Electron. Mater. 3, 1127–1132 (2021).

    Article  CAS  Google Scholar 

  28. Bose, A. et al. Effects of anisotropic strain on spin-orbit torque produced by the Dirac nodal line semimetal IrO2. ACS Appl. Mater. Interfaces 12, 55411–55416 (2020).

    Article  CAS  Google Scholar 

  29. Liu, J. et al. Strain-induced nonsymmorphic symmetry breaking and removal of Dirac semimetallic nodal line in an orthoperovskite iridate. Phys. Rev. B 93, 085118 (2016).

    Article  Google Scholar 

  30. Hou, X., Takahashi, R., Yamamoto, T. & Lippmaa, M. Microstructure analysis of IrO2 thin films. J. Cryst. Growth 462, 24–28 (2017).

    Article  CAS  Google Scholar 

  31. Stoerzinger, K. A., Qiao, L., Biegalski, M. D. & Shao-Horn, Y. Orientation-dependent oxygen evolution activities of rutile IrO2 and RuO2. J. Phys. Chem. Lett. 5, 1636–1641 (2014).

    Article  CAS  Google Scholar 

  32. Abb, M. J. S., Herd, B. & Over, H. Template-assisted growth of ultrathin single-crystalline IrO2(110) films on RuO2(110)/Ru(0001) and its thermal stability. J. Phys. Chem. C 122, 14725–14732 (2018).

    Article  CAS  Google Scholar 

  33. Wang, F. & Senthil, T. Twisted Hubbard model for Sr2IrO4: magnetism and possible high temperature superconductivity. Phys. Rev. Lett. 106, 136402 (2011).

    Article  Google Scholar 

  34. Pesin, D. & Balents, L. Mott physics and band topology in materials with strong spin-orbit interaction. Nat. Phys. 6, 376–381 (2010).

    Article  CAS  Google Scholar 

  35. Wan, X. G., Turner, A. M., Vishwanath, A. & Savrasov, S. Y. Topological semimetal and Fermi-arc surface states in the electronic structure of pyrochlore iridates. Phys. Rev. B 83, 205101 (2011).

    Article  Google Scholar 

  36. Go, A., Witczak-Krempa, W., Jeon, G. S., Park, K. & Kim, Y. B. Correlation effects on 3D topological phases: from bulk to boundary. Phys. Rev. Lett. 109, 066401 (2012).

    Article  Google Scholar 

  37. Guo, L. et al. Searching for a route to synthesize in situ epitaxial Pr2Ir2O7 thin films with thermodynamic methods. npj Comput. Mater. 7, 144 (2021).

    Article  CAS  Google Scholar 

  38. Gutierrez-Llorente, A., Iglesias, L., Rodriguez-Gonzalez, B. & Rivadulla, F. Epitaxial stabilization of pulsed laser deposited Srn+1IrnO3n+1 thin films: entangled effect of growth dynamics and strain. APL Mater 6, 091101 (2018).

    Article  Google Scholar 

  39. Butler, S. R. & Gillson, J. L. Crystal growth, electrical resistivity and lattice parameters of Ruo2 and Iro2. Mater. Res. Bull. 6, 81–88 (1971).

    Article  CAS  Google Scholar 

  40. Sun, Y., Zhang, Y., Liu, C. X., Felser, C. & Yan, B. H. Dirac nodal lines and induced spin Hall effect in metallic rutile oxides. Phys. Rev. B 95, 235104 (2017).

    Article  Google Scholar 

  41. Kawasaki, J. K. et al. Engineering carrier effective masses in ultrathin quantum wells of IrO2. Phys. Rev. Lett. 121, 176802 (2018).

    Article  CAS  Google Scholar 

  42. Kawasaki, J. K. et al. Rutile IrO2/TiO2 superlattices: a hyperconnected analog to the Ruddlesden–Popper structure. Phys. Rev. Mater. 2, 054206 (2018).

    Article  CAS  Google Scholar 

  43. Kawasaki, J. K., Uchida, M., Paik, H., Schlom, D. G. & Shen, K. M. Evolution of electronic correlations across the rutile, perovskite, and Ruddlesden-Popper iridates with octahedral connectivity. Phys. Rev. B 94, 121104 (2016).

    Article  Google Scholar 

  44. Morozova, N. B., Semyannikov, P. P., Sysoev, S. V., Grankin, V. M. & Igumenov, I. K. Saturated vapor pressure of iridium(III) acetylacetonate. J. Therm. Anal. Calorim. 60, 489–495 (2000).

    Article  CAS  Google Scholar 

  45. Freakley, S. J., Ruiz-Esquius, J. & Morgan, D. J. The X-ray photoelectron spectra of Ir, IrO2 and IrCl3 revisited. Surf. Interface Anal. 49, 794–799 (2017).

    Article  CAS  Google Scholar 

  46. Hohenberg, P. & Kohn, W. Inhomogeneous electron gas. Phys. Rev. 136, 7 (1964).

    Article  Google Scholar 

  47. Kohn, W. & Sham, L. J. Self-consistent equations including exchange and correlation effects. Phys. Rev. 140, A1133–A1138 (1965).

    Article  Google Scholar 

  48. Kresse, G. & Hafner, J. Ab initio molecular dynamics for liquid metals. Phys. Rev. B 47, 558–561 (1993).

    Article  CAS  Google Scholar 

  49. Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal–amorphous-semiconductor transition in germanium. Phys. Rev. B 49, 14251–14269 (1994).

    Article  CAS  Google Scholar 

  50. Kresse, G. & Furthmüller, J. Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set. Comput. Mater. Sci. 6, 15–50 (1996).

    Article  CAS  Google Scholar 

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Acknowledgements

We thank N. Seaton for help with SEM, EDX and EBSD. Funding for film growth and characterization (S.N., D.L. and B.J.) was supported by the US Department of Energy through DE-SC0020211. S.N. and D.L. acknowledge support from the Air Force Office of Scientific Research (AFOSR) through grant numbers FA9550-21-1-0025 and FA9550-21-0460. S.G., Z.Y. and K.A.M. were supported partially by the UMN MRSEC program under award number DMR-2011401. S.G. and K.A.M. were also supported by SMART, one of seven centres of nCORE, a Semiconductor Research Corporation program, sponsored by the National Institute of Standards and Technology (NIST). Parts of this work were carried out at the Characterization Facility, University of Minnesota, which receives partial support from the National Science Foundation (NSF) through the MRSEC program under award number DMR-2011401. S.J. acknowledges support from the NSF under award number DMR-2129879. W.J. acknowledges support from the US Department of Energy (DOE) Office of Science under DE-SC0023478. R.B.C. acknowledges support from the AFOSR Young Investigator Program under FA9550-20-1-0034. A.J. and A.S. acknowledge support from the NSF through the UD-CHARM University of Delaware Materials Research Science and Engineering Center (number DMR-2011824). The first-principles calculations used Bridges-2 at PSC through allocation DMR150099 from the Advanced Cyberinfrastructure Coordination Ecosystem: Services & Support (ACCESS) program, which is supported by NSF grant numbers 2138259, 2138286, 2138307, 2137603 and 2138296, and the DARWIN computing system at the University of Delaware, which is supported by NSF grant number 1919839. This research used resources of the Center for Functional Nanomaterials and National Synchrotron Light Source II, which are US DOE Office of Science Facilities, at Brookhaven National Laboratory under contract number DE-SC0012704. This research used resources of the Advanced Photon Source, a DOE Office of Science user facility operated for the DOE Office of Science by Argonne National Laboratory under contract number DE-AC02-06CH11357.

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Authors and Affiliations

  1. Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, USA

    Sreejith Nair, Zhifei Yang, Dooyong Lee, Silu Guo, K. Andre Mkhoyan & Bharat Jalan

  2. School of Physics and Astronomy, University of Minnesota, Minneapolis, MN, USA

    Zhifei Yang

  3. Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, USA

    Jerzy T. Sadowski

  4. Department of Physics, Auburn University, Auburn, AL, USA

    Spencer Johnson, Ryan B. Comes & Wencan Jin

  5. Department of Materials Science and Engineering, University of Delaware, Newark, DE, USA

    Abdul Saboor & Anderson Janotti

  6. Materials Science Division, Argonne National Laboratory, Lemont, IL, USA

    Yan Li

  7. X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, IL, USA

    Hua Zhou

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Contributions

S.N. and B.J. conceived the idea and established proof of concept. S.N. grew films and characterized them using XRD, AFM, optical microscopy, SEM and electrical transport measurements. S.N. and B.J. analysed the data. Z.Y. performed magneto-transport measurements and data analysis. D.L. performed XPS measurements. S.G. performed STEM analysis under the supervision of K.A.M. LEEM, LEED and XPS were performed by J.T.S. and analysed by S.J., W.J. and R.B.C. Y.L. and H.Z. carried out synchrotron X-ray diffraction measurements and data analysis. DFT calculations were performed by A.S. under the supervision of A.J. S.N. and B.J. wrote the manuscript. All authors contributed to the discussion and preparation of the manuscript. B.J. directed and organized the different aspects of the project.

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Correspondence to Sreejith Nair or Bharat Jalan.

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Nature Nanotechnology thanks Scott Chambers, Guangwen Zhou and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Nair, S., Yang, Z., Lee, D. et al. Engineering metal oxidation using epitaxial strain. Nat. Nanotechnol. 18, 1005–1011 (2023). https://doi.org/10.1038/s41565-023-01397-0

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