Positron Annihilation Spectroscopy Measurements

Positron Annihilation Spectroscopy Measurements

Two thrusts, focused on Positron Annihilation Spectroscopy (PAS) and positron trapping, have been conducted at IMR. The PAS system at WSU has been used to study many materials, including Si, Ga2O3, CeO2, UO2, TiO2, perovskite, and CdTe based compounds, with incident positron energies from 0.1 eV to 70 keV. This corresponds to mean implantation depths of 15 µm in Si and 6 µm in CdTe. Doppler broadening experiments can be conducted with this system, in which vacancy and vacancy clusters can be characterized. Further, positron lifetime experiments can be conducted, capable of measuring positron lifetimes up to 142 ns, a system unique in the United States.

We have worked with a number of organizations, measuring materials using our unique positron capabilities.  Some of those organizations are as follows:

  • Pacific Northwest National Laboratory
  • Brookhaven National Laboratory
  • Idaho National Laboratory
  • National Renewable Energy Lab
  • Livermore National Lab
  • II-VI Incorporated, including eV Products
  • National Superconducting Cyclotron Laboratory Michigan State University
  • Universidad Antonio Nariño, Columbia
  • Instituto de Física de Materiales Tandil, Argentina
  • Vanderbilt University
  • University of Florida
  • UCLA
  • U of Utah, Salt Lake City
  • Bekaert, Belgium
  • Outermost Materials

A few selected publications of this work, showing the breadth of materials studied, are indicated below. Bolded are WSU authors.

 

2019 – present

CeO2 and UO2

  • Ritesh Mohun, Théo Cordara, John McCloy, Marc Weber, Claire Corkhill, “Defect chemistry manipulation by heavy ion irradiation in Y-doped CeO2 solid solutions,” Physical Chemistry Chemical Physics, 28(5), 3613-3623 (2026).
  • Marc H. Weber, Sam Karcher, John Bussey, John McCloy, “Positron Annihilation Spectroscopy to Investigate Nuclear Materials,” MRS Advances, 9(7), 467–472 (2024).
  • Marc H. Weber, John S McCloy, Corey R. Halverson, Sam E. Karcher, Ritesh Mohun, Claire L. Corkhill, “Characterization of vacancy type defects in irradiated UO2 and CeO2,” MRS Advances, 7(7), 123-127 (2022). 
  • Marc H. Weber, Sam Karcher, Ritesh Mohun, Claire Corkhill, John McCloy, “Assessment of Positrons for Defect Studies in CeO2 Materials,” MRS Advances, 6(4), 119-124 (2021). 

beta-Ga2O3

  • H.N. Masten, G.A. Alvarez, C. Halverson, J. Christiansen-Salameh, E.Y. Kwon, M. Liao, J.S. Lundh, A.R. Gutierrez, F. Alema, A. Osinsky, A.G. Jacobs, M.S. Goorsky, M.H. Weber, Z.T. Tian, K.D. Hobart, M.J. Tadjer, “Structural, electrical, and thermal characterization of homoepitaxial close-injection showerhead metalorganic chemical vapor deposition β-Ga2O3 enhancement-mode recessed-gate MOSFETs”, J. Vac. Sci. Technol. A 43, 022703 (2025).
  • Marc H. Weber, Corey Halverson, John S. McCloy, “Positron Annihilation Spectroscopy of Vacancy Type Defects in Electron Irradiated b-Ga2O3,” physica status solidi (b), 62(8), 2400428 (2025).
  • John S. McCloy, Jani Jesenovec, Benjamin L. Dutton, Christopher Pansegrau, Cassandra Remple, Marc H. Weber, Santosh Swain, Matthew McCluskey, Michael Scarpulla. “Growth and defect characterization of doped and undoped β-Ga2O3 crystals,” Proc. SPIE 12002, 1200205 (2022). 
  • Santosh Swain, Marc Weber, Jani Jesenovec, Muad Saleh, Kelvin Lynn, John McCloy, “Compensation of shallow donors by gallium vacancies in β-Ga2O3,” Physical Review Applied, 15(5), 054010 (2021).
  • Jani Jesenovec, Marc Weber, Christopher Pansegrau, Matthew McCluskey, Kelvin Lynn, and John McCloy, “Gallium Vacancy Formation in Oxygen Annealed β-Ga2O3,” Journal of Applied Physics, 129(24), 245701 (2021).

Perovskites

  • Y.P. Zhao, I. Yavuz, M.H. Wang, M.H. Weber, M.J. Xu, J.H. Lee, S. Tan, T.Y. Huang, D. Meng, R. Wang, J.J. Xue, S.J. Lee, S.H. Bae, A. Zhang, S.G. Choi, Y.F. Yin, J. Liu, T.H. Han, Y.T. Shi, H.R. Ma, W.X. Yang, Q.Y. Xing, Y.F. Zhou, P.J. Shi, S.S. Wang, E. Zhang, J.M. Bian, X.Q. Pan, N.G. Park, J.W. Lee, Y. Yang, “Suppressing ion migration in metal halide perovskite via interstitial doping with a trace amount of multivalent cations”, Nature Materials 21, 1396 (2022).
  • T.Y. Huang, R. Wang, S. Nuryyeva, S. Tan, J.J. Xue, Y.P. Zhao, Q.T. Wu, M.H. Weber, P. Cheng, D. Meng, I. Yavuz, K.N. Houk, Y. Yang, “Wide-Gap Perovskite via Synergetic Surface Passivation and Its Application toward Efficient Stacked Tandem Photovoltaics”, Small 18, 2103887 (2022).
  • T.Y. Huang, S. Tan, S. Nuryyeva, I. Yavuz, F. Babbe, Y. Zhao, M. Abdelsamie, M.H. Weber, R. Wang, K.N. Houk, C.M. Sutter-Fella, Y. Yang, “Performance-limiting formation dynamics in mixed-halide perovskites”, Science Advances 7, eabj1799 (2021).
  • S. Tan, T.Y. Huang, I. Yavuz, R. Wang, M.H. Weber, Y.P. Zhao, M. Abdelsamie, M.E. Liao, H.C. Wang, K. Huynh, K.H. Wei, J.J. Xue, F. Babbe, M.S. Goorsky, J.W. Lee, C.M. Sutter-Fella, Y. Yang, “Surface Reconstruction of Halide Perovskites During Post-treatment”, Journal of the American Chemical Society 143, 6781-6786 (2021).

Silicon

  • H.C. Jacks, M. Molina-Ruiz, M.H. Weber, J.J. Maldonis, P.M. Voyles, M.R. Abernathy, T.H. Metcalf, X. Liu, F. Hellman, “Structural tunability and origin of two-level systems in amorphous silicon”, Physical Review Materials 6, 045604 (2022).
  • M.C. Adam, N. Darukhanawalla, J.M. Gaudet, G. O’Hara, P. Harford, G. Hall, J. Ociepa, M.H. Weber, P.J. Simpson, L.V. Goncharova, “Surface Debye temperature determination from LEED: correlation to defects in epitaxial films”, Surface Science 723, 122104 (2022).

Miscellaneous Materials

  • D. Sukalingum, T.R. Zhai, M.H. Weber, S.A. Khan, T.H. Htut, J.I. Feldblyum, “Pore Network Percolation in Polymers of Intrinsic Microporosity Examined by Gaseous and Antimatter Probes”, Macromolecules 58, 11171-11179 (2025). 
  • Y. Yang, X.F. Brun, M.H. Weber, M. Flores, “Quantification of Interfacial Voids Using Positron Annihilation Spectroscopy for Mechanism Study on SiCN Bonding and SiN Bonding”, ECS J. Solid State Sci. Technol. 13, 113002, (2024).
  • I.S. Garcia, C.A.P. Gomez, M.H. Weber, I.M.S. Gaona, C.P.C. Martinez, J.J.M. Zambrano, H.A.R. Sarmiento, J.A.M. Cagigas, M.A. Avila, C. Rettori, C.A.P. Vargas, J.A.M. Gomez, “Physicochemical Properties of Ti3+ Self-Doped TiO2 Loaded on Recycled Fly-Ash Based Zeolites for Degradation of Methyl Orange”, Condensed Matter 7, 69 (2022).
  • S.T. Jaszewski, E.R. Hoglund, A. Costine, M.H. Weber, S.S. Fields, M.G. Sales, J. Vaidya, L. Bellcase, K. Loughlin, A. Salanova, D.A. Dickie, S.L. Wolfley, M.D. Henry, J.P. Maria, J.L. Jones, N. Shukla, S.J. McDonnell, P. Reinke, P.E. Hopkins, J.M. Howe, J.F. Ihlefeld, “Impact of oxygen content on phase constitution and ferroelectric behavior of hafnium oxide thin films deposited by reactive high-power impulse magnetron sputtering”, Acta Materialia 239, 118220 (2022).
  • G.I. Supelano, C.A. Palacio, M.H. Weber, J.S. McCoy, J. Jennings, J.A.M. Gomez, C.A.P. Vargas, C. Ortiz, K.G. Lynn, “Study of fly-ash based zeolite by using slow positrons”, Materials Science and Engineering B — Advanced Functional Solid-State Materials 263, 114890 (2021).
  • Xu, K., M.H. Weber, Y. Cao, W. Jiang, D.J. Edwards, B.R. Johnson, and J.S. McCloy, “Ion irradiation induced changes in defects of iron thin films: Electron microscopy and positron annihilation spectroscopy,” Journal of Nuclear Materials, 526, 151774 (2019).

1998-2018

  • Parmar, N.S., L.A. Boatner, K.G. Lynn, and J.-W. Choi, “Zn Vacancy Formation Energy and Diffusion Coefficient of CVT ZnO Crystals in the Sub-Surface Micron Region,” Scientific Reports, 8(1), 13446 (2018).
  • Reiser, J.T., B. Parruzot, M.H. Weber, J.V. Ryan, J.S. McCloy, and N.A. Wall, “The use of positrons to survey alteration layers on synthetic nuclear waste glasses,” Journal of Nuclear Materials, 490, 75-84 (2017).
  • Lund, K., K. Lynn, M. Weber, C. Liu, and E. Eissler, “Nitrogen Desorption and Positron Sensitive Defect of CVD Diamond,” Journal of Modern Physics, 8, 770-785 (2017).
  • Lund, K.R., K.G. Lynn, M.H. Weber, C. Macchi, A. Somoza, A. Juan, and M.A. Okuniewski, “Impurity migration and effects on vacancy formation enthalpy in polycrystalline depleted uranium,” Journal of Nuclear Materials, 466, 343-350 (2015).
  • Parmar, N.S., K.G. Lynn, “Sodium doping in ZnO crystals,” Applied Physics Letters, 106(2), 022101 (2015).
  • Selim, F., D. Solodovnikov, M. Weber, and K. Lynn, “Identification of defects in Y3Al5O12 crystals by positron annihilation spectroscopy,” Applied Physics Letters, 91, 104105-104105 (2007).
  • Weber, M.H. and K.G. Lynn, “Positron Porosimetry,” In Principles and Applications of Positron and Positronium Chemistry, Y.C. Jean, P.E. Mellon, and D.M. Schrader, World Scientific Pub. Co., Hackensack, NJ, 167-209 (2003).
  • Keeble, D., B. Nielsen, A. Krishnan, K. Lynn, S. Madhukar, R. Ramesh, and C. Young, “Vacancy defects in (Pb, La)(Zr, Ti)O3 capacitors observed by positron annihilation,” Applied Physics Letters, 73, 318-320 (1998).