Carnegie Mellon University
Synthesis

SYNTHESIS

Tools: we are using three workhorse deposition systems.

Molecular Beam Epitaxy - Synthesis

Molecular Beam Epitaxy
for complex oxide hetero-structures: LaAlO3/SrTiO3, GdTiO3/SrTiO3, Vo2/TiO2…The MBE chamber is a part of an integrated characterization / deposition system consisting of X-ray Photoelectron Spectroscopy tool, Low Energy Electron Diffraction, and Scanning Tunneling Microscope. The deposited structures can be evaluated without their surfaces ever being exposed to and contaminated by ambient. We study the termination and reconstructions of differently prepared surfaces. The overarching goal is to understand the growth process of oxides and effects of growth stoichiometry on their properties.

PLD growth trgh viewport

Sputtering for dielectric oxides, chalcogenides and their alloys. This tool is used for deposition of both electrodes (Ta, TiN, Pt) and functional layers for RRAM switching devices.

Pulsed Laser Deposition for single crystal binary oxides. The examples of devices fabricated on VO2 and NbO2 layers are shown in Devices page

Funding:                       Collaboration:

AirForce Office of Scientific Research                               

Recent publications:

"Oxygen vacancies on SrO-terminated SrTiO3 (001) sufaces studied by scanning tunneling microscopy", W. Sitaputra, N. Sivadas, M. Skowronski, D. Xiao, and R. M. Feenstra, Phys. Rev. B 91, 205408 (2015)

"Topographic and electronic structure of cleaved SrTiO3 (001) surfaces", W. Sitaputra, M. Skowronski, and R. M. Feenstra, J. Vac. Sci. Technol. A 33, 031402 (2015)

“Controlling the Bi content, phase formation, and epitaxial nature of BiMnO3 thin films fabricated using conventional pulsed laser deposition, hybrid pulsed laser deposition, and solid state epitaxy”, S. Havelia, S. Wang, M. Skowronski, and P. A. Salvador, J. Appl. Phys. 106, 123509 (2009)

“MgO films grown on yttria-stabilized zirconia by molecular beam epitaxy”, O. Maksimov, P. J.  Fisher, M. Skowronski, P. A. Salvador, M. Snyder, J, Xu, and X. Weng, J. Crystal Growth 310, 2760 (2008)

“Growth and structural characterization of epitaxial Ba0.6Sr0.4TiO3 films deposited on REScO3 (110) (RE = Dy, Gd) substrates using pulsed laser deposition”, H. Du, P. J. Fisher, M. Skowronski M, P. A. Salvador,  and O. Maksimov, J. Crystal Growth 310, 1991 (2008)

“Structural characterization of TiO2  films grown on LaAlO3 and SrTiO3 substrates using reactive molecular beam epitaxy”, X. Weng, P. J. Fisher, M. Skowronski, P. A. Salvador, and O. Maksimov,  J.  Crystal Growth 310, 545 (2008)

“Stoichiometric, nonstoichiometric, and locally nonstoichiometric SrTiO3 films grown by molecular beam epitaxy”, P. Fisher, H. Du, M. Skowronski, P. A. Salvador, O. Maksimov, and X. Weng, J. Appl. Phys. 103, 013519 (2008)

“Structural characterization of TiO2 films grown on LaAlO3 and SrTiO3 substrates using reactive molecular beam epitaxy”, X. Weng, P. Fisher, M. Skowronski, P. A. Salvador and O. Maksimov, J. Crystal Growth, 310, 545 (2008)