Correlating surface stoichiometry and termination in SrTiO3 films grown by hybrid molecular beam epitaxy

Thapa, Suresh; Provence, Sydney R.; Jessup, Devin; Lapano, Jason; Brahlek, Matthew; Sadowski, Jerzy T.; Reinke, Petra; Jin, Wencan; Comes, Ryan B.

doi:10.1116/6.0001159

Correlating surface stoichiometry and termination in SrTiO3 films grown by hybrid molecular beam epitaxy

Journal Article · Thu Jul 22 00:00:00 EDT 2021 · Journal of Vacuum Science and Technology A

DOI:https://doi.org/10.1116/6.0001159· OSTI ID:1811458

Thapa, Suresh ^[1]; Provence, Sydney R. ^[1]; Jessup, Devin ^[2]; ^[3]; ^[3]; ^[4]; ^[2]; ^[1]; ^[1]

Auburn Univ., AL (United States)
Univ. of Virginia, Charlottesville, VA (United States)
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Materials Science & Technology Division
Brookhaven National Lab. (BNL), Upton, NY (United States). Center for Functional Nanomaterials (CFN)

Hybrid oxide molecular beam epitaxy (hMBE), a thin-film deposition technique in which transition metal cations are delivered using a metal-organic precursor, has emerged as the state-of-the-art approach to the synthesis of electronic-grade complex oxide films with a stoichiometric growth window. However, numerous questions remain regarding the chemical mechanisms of the growth process and the surface properties of the resulting films. To examine these properties, thin film SrTiO₃ (STO) was prepared by hMBE using a titanium tetraisopropoxide (TTIP) precursor for Ti delivery and an elemental Sr source on annealed STO and Nb-doped STO substrates with varying TTIP:Sr flux ratios to examine the conditions for the reported stoichiometric growth window. The films were transferred in vacuo to an x-ray photoelectron spectroscopy system to study the surface elemental composition. Samples were examined using x-ray diffraction to compare our surface sensitive results with previously reported measurements of the bulk of the films in the literature. Ex situ studies by atomic force microscopy, scanning tunneling microscopy, and low-energy electron microscopy confirmed the presence of surface reconstructions and an Ehrlich–Schwoebel barrier consistent with A-site SrO termination. We find that a surface exhibiting a mixture of SrO and TiO₂ termination or a full SrO termination is necessary to obtain stoichiometric adsorption-controlled growth. These results indicate that surface Sr is necessary to maintain the chemical equilibrium for stoichiometric growth during the hMBE process, which is important for the design of future interfacial systems using this technique.

View Accepted Manuscript (DOE)

Research Organization:: Brookhaven National Laboratory (BNL), Upton, NY (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Organization:: USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES)

Grant/Contract Number:: AC05-00OR22725; SC0012704

OSTI ID:: 1811458

Alternate ID(s):: OSTI ID: 1809273
OSTI ID: 1812477
OSTI ID: 1813336
OSTI ID: 1856722

Report Number(s):: BNL--221927-2021-JAAM; BNL--221986-2021-JAAM

Journal Information:: Journal of Vacuum Science and Technology A, Journal Name: Journal of Vacuum Science and Technology A Journal Issue: 5 Vol. 39; ISSN 0734-2101

Publisher:: American Vacuum Society / AIPCopyright Statement

Country of Publication:: United States

Language:: English

References (50)

Frontiers in the Growth of Complex Oxide Thin Films: Past, Present, and Future of Hybrid MBE Brahlek, Matthew; Gupta, Arnab Sen; Lapano, Jason Advanced Functional Materials, Vol. 28, Issue 9 https://doi.org/10.1002/adfm.201702772	journal	December 2017
On the shape of wedding cakes Krug, Joachim Journal of Statistical Physics, Vol. 87, Issue 3-4 https://doi.org/10.1007/BF02181234	journal	May 1997
No coarsening in Pt(111) homoepitaxy Kalff, M.; Šmilauer, P.; Comsa, G. Surface Science, Vol. 426, Issue 3 https://doi.org/10.1016/S0039-6028(99)00351-9	journal	May 1999
Understanding the mechanism of conductivity at the LaAlO3/SrTiO3(001) interface Chambers, Scott A. Surface Science, Vol. 605, Issue 13-14 https://doi.org/10.1016/j.susc.2011.04.011	journal	July 2011
Water adsorption on SrTiO3(001): II. Water, water, everywhere Becerra-Toledo, A. E.; Enterkin, J. A.; Kienzle, D. M. Surface Science, Vol. 606, Issue 9-10 https://doi.org/10.1016/j.susc.2012.01.010	journal	May 2012
Quantifying work function differences using low-energy electron microscopy: The case of mixed-terminated strontium titanate Jobst, Johannes; Boers, Laurens M.; Yin, Chunhai Ultramicroscopy, Vol. 200 https://doi.org/10.1016/j.ultramic.2019.02.018	journal	May 2019
Quantification of La Dopant Level in La:SrSnO ₃ /SrSnO ₃ /BaSnO ₃ Heterostructures with STEM-EELS Yun, Hwanhui; Held, Jacob; Prakash, Abhinav Microscopy and Microanalysis, Vol. 25, Issue S2 https://doi.org/10.1017/S1431927619011280	journal	August 2019
Growth Mode Transition in Complex Oxide Heteroepitaxy: Atomically Resolved Studies Tselev, Alexander; Vasudevan, Rama K.; Gianfrancesco, Anthony G. Crystal Growth & Design, Vol. 16, Issue 5 https://doi.org/10.1021/acs.cgd.5b01826	journal	April 2016
Instability and Surface Potential Modulation of Self-Patterned (001)SrTiO ₃ Surfaces Aballe, Lucía; Matencio, Sonia; Foerster, Michael Chemistry of Materials, Vol. 27, Issue 18 https://doi.org/10.1021/acs.chemmater.5b00661	journal	September 2015
Influence of LaFeO ₃ Surface Termination on Water Reactivity Stoerzinger, Kelsey A.; Comes, Ryan; Spurgeon, Steven R. The Journal of Physical Chemistry Letters, Vol. 8, Issue 5 https://doi.org/10.1021/acs.jpclett.7b00195	journal	February 2017
In Situ Monitoring of Composition and Sensitivity to Growth Parameters of Pulsed Laser Deposition Orvis, Thomas; Kumarasubramanian, Harish; Surendran, Mythili ACS Applied Electronic Materials, Vol. 3, Issue 3 https://doi.org/10.1021/acsaelm.1c00024	journal	February 2021
Big-Data Reflection High Energy Electron Diffraction Analysis for Understanding Epitaxial Film Growth Processes Vasudevan, Rama K.; Tselev, Alexander; Baddorf, Arthur P. ACS Nano, Vol. 8, Issue 10 https://doi.org/10.1021/nn504730n	journal	October 2014
RHEED Intensity Oscillations for the Stoichiometric Growth of SrTiO₃ Thin Films by Reactive Molecular Beam Epitaxy Haeni, J. H.; Theis, C. D.; Schlom, D. G. Journal of Electroceramics, Vol. 4, Issue 2/3, p. 385-391 https://doi.org/10.1023/A:1009947517710	journal	January 2000
A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface Ohtomo, A.; Hwang, H. Y. Nature, Vol. 427, Issue 6973 https://doi.org/10.1038/nature02308	journal	January 2004
Atomically precise interfaces from non-stoichiometric deposition Nie, Y. F.; Zhu, Y.; Lee, C. -H. Nature Communications, Vol. 5, Issue 1 https://doi.org/10.1038/ncomms5530	journal	August 2014
Why some interfaces cannot be sharp Nakagawa, Naoyuki; Hwang, Harold Y.; Muller, David A. Nature Materials, Vol. 5, Issue 3, p. 204-209 https://doi.org/10.1038/nmat1569	journal	January 2006
Epitaxial SrTiO₃ films with electron mobilities exceeding 30,000 cm² V^-1 s^-1 Son, Junwoo; Moetakef, Pouya; Jalan, Bharat Nature Materials, Vol. 9, Issue 6, p. 482-484 https://doi.org/10.1038/nmat2750	journal	April 2010
Dynamic layer rearrangement during growth of layered oxide films by molecular beam epitaxy Lee, J. H.; Luo, G.; Tung, I. C. Nature Materials, Vol. 13, Issue 9 https://doi.org/10.1038/nmat4039	journal	August 2014
Adsorption-controlled growth and the influence of stoichiometry on electronic transport in hybrid molecular beam epitaxy-grown BaSnO ₃ films Prakash, Abhinav; Xu, Peng; Wu, Xuewang Journal of Materials Chemistry C, Vol. 5, Issue 23 https://doi.org/10.1039/C7TC00190H	journal	January 2017
Molecular beam epitaxy of SrTiO3 with a growth window Jalan, Bharat; Moetakef, Pouya; Stemmer, Susanne Applied Physics Letters, Vol. 95, Issue 3 https://doi.org/10.1063/1.3184767	journal	July 2009
Stoichiometry optimization of homoepitaxial oxide thin films using x-ray diffraction LeBeau, James M.; Engel-Herbert, Roman; Jalan, Bharat Applied Physics Letters, Vol. 95, Issue 14 https://doi.org/10.1063/1.3243696	journal	October 2009
Enhancing the electron mobility of SrTiO3 with strain Jalan, Bharat; Allen, S. James; Beltz, Glenn E. Applied Physics Letters, Vol. 98, Issue 13 https://doi.org/10.1063/1.3571447	journal	March 2011
Electrostatic carrier doping of GdTiO ₃ /SrTiO ₃ interfaces Moetakef, Pouya; Cain, Tyler A.; Ouellette, Daniel G. Applied Physics Letters, Vol. 99, Issue 23 https://doi.org/10.1063/1.3669402	journal	December 2011
Two-dimensional electron gas in a modulation-doped SrTiO ₃ /Sr(Ti, Zr)O ₃ heterostructure Kajdos, Adam P.; Ouellette, Daniel G.; Cain, Tyler A. Applied Physics Letters, Vol. 103, Issue 8 https://doi.org/10.1063/1.4819203	journal	August 2013
The surface structure of SrTiO ₃ at high temperatures under influence of oxygen Hesselberth, M. B. S.; van der Molen, S. J.; Aarts, J. Applied Physics Letters, Vol. 104, Issue 5 https://doi.org/10.1063/1.4864186	journal	February 2014
Surface reconstructions in molecular beam epitaxy of SrTiO ₃ Kajdos, Adam P.; Stemmer, Susanne Applied Physics Letters, Vol. 105, Issue 19 https://doi.org/10.1063/1.4901726	journal	November 2014
Accessing a growth window for SrVO3 thin films Brahlek, Matthew; Zhang, Lei; Eaton, Craig Applied Physics Letters, Vol. 107, Issue 14 https://doi.org/10.1063/1.4932198	journal	October 2015
Impact of built-in potential across LaFeO3/SrTiO3 heterojunctions on photocatalytic activity Nakamura, Kentarou; Mashiko, Hisanori; Yoshimatsu, Kohei Applied Physics Letters, Vol. 108, Issue 21 https://doi.org/10.1063/1.4952736	journal	May 2016
New approaches for achieving more perfect transition metal oxide thin films MacManus-Driscoll, J. L.; Wells, Matthew P.; Yun, Chao APL Materials, Vol. 8, Issue 4 https://doi.org/10.1063/5.0003268	journal	April 2020
New In-Situ and Operando Facilities for Catalysis Science at NSLS-II: The Deployment of Real-Time, Chemical, and Structure-Sensitive X-ray Probes Palomino, Robert M.; Stavitski, Eli; Waluyo, Iradwikanari Synchrotron Radiation News, Vol. 30, Issue 2 https://doi.org/10.1080/08940886.2017.1289805	journal	March 2017
Spectroscopic photoemission and low-energy electron microscopy studies of the surface and electronic structure of two-dimensional materials Jin, Wencan; Osgood, Richard M. Advances in Physics: X, Vol. 4, Issue 1 https://doi.org/10.1080/23746149.2019.1688187	journal	January 2019
The Ehrlich–Schwoebel barrier on an oxide surface: a combined Monte-Carlo and in situ scanning tunneling microscopy approach Gianfrancesco, Anthony G.; Tselev, Alexander; Baddorf, Arthur P. Nanotechnology, Vol. 26, Issue 45 https://doi.org/10.1088/0957-4484/26/45/455705	journal	October 2015
Electronic transport in doped SrTiO 3 : Conduction mechanisms and potential applications Spinelli, A.; Torija, M. A.; Liu, C. Physical Review B, Vol. 81, Issue 15 https://doi.org/10.1103/PhysRevB.81.155110	journal	April 2010
Interface properties and built-in potential profile of a LaCr O 3 / SrTi O 3 superlattice determined by standing-wave excited photoemission spectroscopy Lin, S. -C.; Kuo, C. -T.; Comes, R. B. Physical Review B, Vol. 98, Issue 16 https://doi.org/10.1103/PhysRevB.98.165124	journal	October 2018
Spontaneous Polarization and Bulk Photovoltaic Effect Driven by Polar Discontinuity in LaFeO 3 / SrTiO 3 Heterojunctions Nakamura, M.; Kagawa, F.; Tanigaki, T. Physical Review Letters, Vol. 116, Issue 15 https://doi.org/10.1103/PhysRevLett.116.156801	journal	April 2016
Interface Structure, Band Alignment, and Built-In Potentials at LaFeO 3 / n − SrTiO 3 Heterojunctions Comes, Ryan; Chambers, Scott Physical Review Letters, Vol. 117, Issue 22 https://doi.org/10.1103/PhysRevLett.117.226802	journal	November 2016
Dynamic interface rearrangement in LaFeO 3 / n − SrTiO 3 heterojunctions Spurgeon, Steven R.; Sushko, Peter V.; Chambers, Scott A. Physical Review Materials, Vol. 1, Issue 6 https://doi.org/10.1103/PhysRevMaterials.1.063401	journal	November 2017
Surface reconstructions and modified surface states in L a 1 − x C a x Mn O 3 Vasudevan, Rama K.; Dixit, Hemant; Tselev, Alexander Physical Review Materials, Vol. 2, Issue 10 https://doi.org/10.1103/PhysRevMaterials.2.104418	journal	October 2018
Hopping transport in SrTi O 3 / N d 1 − x Ti O 3 / SrTi O 3 heterostructures Thoutam, Laxman Raju; Yue, Jin; Xu, Peng Physical Review Materials, Vol. 3, Issue 6 https://doi.org/10.1103/PhysRevMaterials.3.065006	journal	June 2019
Influence of crystalline order and defects on the absolute work functions and electron affinities of Ti O 2 - and SrO-terminated n − SrTi O 3 ( 001 ) Chambers, Scott A.; Sushko, Peter V. Physical Review Materials, Vol. 3, Issue 12 https://doi.org/10.1103/PhysRevMaterials.3.125803	journal	December 2019
Surface reconstruction and band alignment of nonmetallic A ( II ) B ( IV ) O 3 perovskites Sung, Ha-Jun; Mochizuki, Yasuhide; Oba, Fumiyasu Physical Review Materials, Vol. 4, Issue 4 https://doi.org/10.1103/PhysRevMaterials.4.044606	journal	April 2020
Machine learning analysis of perovskite oxides grown by molecular beam epitaxy Provence, Sydney R.; Thapa, Suresh; Paudel, Rajendra Physical Review Materials, Vol. 4, Issue 8 https://doi.org/10.1103/PhysRevMaterials.4.083807	journal	August 2020
Growth of high-quality SrTiO3 films using a hybrid molecular beam epitaxy approach Jalan, Bharat; Engel-Herbert, Roman; Wright, Nicholas J. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 27, Issue 3 https://doi.org/10.1116/1.3106610	journal	May 2009
Analysis of carbon in SrTiO3 grown by hybrid molecular beam epitaxy Jalan, Bharat; Cagnon, Joël; Mates, Thomas E. Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 27, Issue 6 https://doi.org/10.1116/1.3253355	journal	November 2009
Crucible aperture: An effective way to reduce source oxidation in oxide molecular beam epitaxy process Kim, Yong-Seung; Bansal, Namrata; Oh, Seongshik Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 28, Issue 4 https://doi.org/10.1116/1.3449051	journal	July 2010
Temperature-dependent growth window of CaTiO ₃ films grown by hybrid molecular beam epitaxy Roth, Joseph; Arriaga, Eddy; Brahlek, Matthew Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, Vol. 36, Issue 2 https://doi.org/10.1116/1.5011384	journal	March 2018
Introductory guide to the application of XPS to epitaxial films and heterostructures Chambers, Scott A.; Wang, Le; Baer, Donald R. Journal of Vacuum Science & Technology A, Vol. 38, Issue 6 https://doi.org/10.1116/6.0000465	journal	December 2020
Atomic Control of the SrTiO₃ Crystal Surface Kawasaki, M.; Takahashi, K.; Maeda, T. Science, Vol. 266, Issue 5190, p. 1540-1542 https://doi.org/10.1126/science.266.5190.1540	journal	December 1994
Probing surfaces and interfaces in complex oxide films via in situ X-ray photoelectron spectroscopy Thapa, Suresh; Paudel, Rajendra; Blanchet, Miles D. Journal of Materials Research, Vol. 36, Issue 1 https://doi.org/10.1557/s43578-020-00070-9	journal	January 2021
Gwyddion: an open-source software for SPM data analysis Nečas, David; Klapetek, Petr Open Physics, Vol. 10, Issue 1 https://doi.org/10.2478/s11534-011-0096-2	journal	January 2012

Similar Records

Stoichiometry-dependent surface electronic structure of SrTiO3 films grown by hybrid molecular beam epitaxy

Journal Article · Wed Mar 23 20:00:00 EDT 2022 · Applied Physics Letters · OSTI ID:1856535

Related Subjects

36 MATERIALS SCIENCE

Correlating surface stoichiometry and termination in SrTiO3 films grown by hybrid molecular beam epitaxy

Citation Formats

References (50)

Similar Records

Related Subjects