Argonne National Laboratory

Guangxu Ju

Postdoctoral Appointee (Supervisor: G. Brian Stephenson)

Dr. Guangxu Ju joined Argonne as a Postdoctoral Appointee in Material Science Division's Synchrotron Studies of Materials group, understanding the surface evolution during epitaxial thin film growth by metalorganic vapor phase epitaxy and radiofrequency reactive magnetron sputtering. Prior to joining Argonne, Guangxu worked at Nagoya University as a staff researcher and received her Ph.D. in Crystalline Material Science from Nagoya University. She is currently working on two projects:

Project: A metal-organic vapor phase epitaxy (MOVPE) system for in situ coherent x-ray studies of III-nitride growth.  

Goal: Applying coherent x-ray techniques (surface x-ray photon correlation spectroscopy (XPCS)) to observe the atomic-scale dynamics during growth;  enhancing our fundamental understanding MOVPE growth mechanism and allow development of improved synthesis and interface science for nitride materials.

Project: Real time X-ray Monitoring of Nucleation of AlN on sapphire (0001) during radiofrequency sputtering

Goal: To observe the properties of extremely thin nucleation layers and follow the structural evolution of strain and roughness in the AlN layer from an initial nucleation layer to a fully relaxed film; To reveal the evolution of the crystal structure, dislocation behavior, and surface and interface roughness during heteroepitaxial growth of a large lattice mismatch system.

Research interest

In-situ x-ray studies of materials processing, characterization, and properties; x-ray scattering for surface evolution during epitaxial thin films; exploring the buried interfaces with advanced x-ray techniques; development of in-situ x-ray techniques; metalorganic vapor phase epitaxy and reactive magnetron sputtering thin film growth of wide band gap semiconductors; nanostructured materials; optical and electronic properties of the semiconductors;

Education

  • 2009-2012 Ph.D in Crystalline Material Science, Nagoya University, Japan
  • 2007-2009 M.Sc. in Materials Science, Harbin Institutes of Technology, China
  • 2002-2006 B.Sc. in Polymer Physics and Chemistry, Heilongjiang University, China   

Selected Publications

  •  Guangxu Ju, Matthew J. Highland, Carol Thompson, Jeffrey A. Eastman, Hua Zhou, Peter M. Baldo, G.Brian Stephenson, and Paul H. Fuoss, “Development of a metal-organic vapor phase epitaxy growth system for in situ studies of III-nitride growth using coherent x-rays scattering probes”, Review of Scientific Instruments, vol.88, 035113 (2017).
  • Matthew Highland, Dillon D. Fong, Guangxu Ju, Carol Thompson, Pete Baldo, Paul Fuoss, and Jeffrey A. Eastman,“In-situ X-ray Studies of Compositional Con trol during Synthesis of LaGaO3 by RF-Magnetron Sputtering”, Applied Physics Letters, vol.107, 081606 (2015).
  • Guangxu Ju, Shingo Fuchi, Masao Tabuchi, Hiroshi Amano, and Yoshikazu Takeda, “Continuous in situ X-ray reflectivity investigation on InGaN epitaxial growth by metalorganic vapor phase epitaxy”, Journal of Crystal Growth, Vol.407, pp. 68-73 (2014).
  • Guangxu Ju, Yoshio Honda, Masao Tabuchi, Yoshikazu Takeda, and Hiroshi Amano; “In situ X-ray investigation of changing barrier growth temperatures on InGaN single quantum wells in metal-organic vapor phase epitaxy”, Journal of Applied Physics, Vol. 115, pp.094906 (2014).
  • Guangxu Ju, Shingo Fuchi, Masao Tabuchi, Yoshikazu Takeda, and Hiroshi Amano: “X-ray investigations of GaInN single quantum wells grown by atomic layer epitaxy and metalorganic vapor phase epitaxy”, Physics Status Solidi C, Vol. 11, pp. 393-396 (2014).
  • Guangxu Ju, Shingo Fuchi, Masao Tabuchi, and Yoshikazu Takeda: “In situ X-ray reflectivity of indium supplied on GaN templates by Metalorganic Vapor Phase Epitaxy”, Journal of Applied Physics, Vol.114, pp.124906-124913 (2013).
  • Guangxu Ju, Shingo Fuchi, Masao Tabuchi, and Yoshikazu Takeda: “In situ X-ray measurements of MOVPE growth of InxGa1-xN single quantum well”, Journal of Crystal Growth, Vol. 370, pp. 36-41 (2013).
  • Guangxu Ju, Shingo Fuchi, Masao Tabuchi, and Yoshikazu Takeda: “In situ X-ray Reflectivity Measurements on Annealed InxGa1-xN Epilayer Grown by Metalorganic Vapor Phase Epitaxy”, Japanese Journal of Applied Physics, Part 1 Vol. 52, No. 8, pp. 08JB12-1-08JB125 (2013).
  • Guangxu Ju, Koji Ninoi, Hajime Kamiya, Shingo Fuchi, Masao Tabuchi, and Yoshikazu Takeda: “X-ray character- ization at growth temperatures of InxGa1-xN growth by MOVPE”, Journal of Crystal Growth, Vol. 318, pp. 1143-1146 (2011).