Thick BaTiO3 Epitaxial Films Integrated on Si by RF Sputtering for Electro-Optic Modulators in Si Photonics
Abstract
Thick epitaxial BaTiO 3 films ranging from 120 nm to 1 μm were grown by off-axis RF magnetron sputtering on SrTiO 3 -templated silicon-on-insulator (SOI) substrates for use in electro-optic applications, where such large thicknesses are necessary. The films are of high quality, rivaling those grown by molecular beam epitaxy (MBE) in crystalline quality, but can be grown 10 times faster. Extraction of lattice parameters from geometric phase analysis of atomic-resolution scanning transmission electron microscopy images revealed how the in-plane and out-of-plane lattice spacings of sputtered BaTiO 3 changes as a function of layer position within a thick film. Our results indicate that compared to molecular beam epitaxy, sputtered films retain their out-of-plane polarization ( c -axis) orientation for larger thicknesses. We also find an unusual re-transition from in-plane polarization ( a -axis) to out-of-plane polarization ( c -axis), along with an anomalous lattice expansion, near the surface. We also studied a method of achieving 100% a -axis-oriented films using a two-step process involving amorphous growth and recrystallization of a seed layer followed by normal high temperature growth. While this method is successful in achieving full a -axis orientation even at low thicknesses, the resulting film has a large number of voids and misoriented grains. Electro-optic measurement using a transmission setup of a sputtered BTO film grown using the optimized conditions yields an effective Pockels coefficient as high as 183 pm/V. A Mach–Zehnder modulator fabricated on such films exhibits phase shifting with an equivalent Pockels coefficient of 157 pm/V. These results demonstrate that sputtered BTO thick films can be used for integrated electro-optic modulators for Si photonics.
Integrity signals
Registry
Cites
Statistics
Claims the paper makes
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
BaTiO3 has a transparency window from 460 to 6300 nm, high refractive index, and can be epitaxially integrated on silicon-on-insulator substrates.
“Similarly to LN, due to its transparency window that is wide, from 460 to 6300 nm, BTO becomes another candidate for communication technology. Waveguides are a possible application of this ferroelectric material, due to its high refractive index value as well as its epitaxial integration on siliconon-insulator substrates [204-208].”
From Metal Oxide Thin Films for Advanced Photonic Applications (2026) · cites this paper as [208]
Electro-optic modulation has been shown to depend on input angle, and θi = 0° is the angular input corresponding to maximum electro-optic modulation for 4 mm BaTiO3 barring misalignments.
“EO modulation has been shown to depend on the input angle, and this angle has been shown to be the angular input corresponding to maximum electro-optic modulation for 4 mm BTO barring any misalignments of the optical setup or sample mounting 23,44 .”
From Enhancement of Electro-Optic Response in BaTiO3 Films Integrated on Si via Heating and Cooling Rate Control (2025) · cites this paper as [44]
Cites
Thornton, J. A. (1977) · Annual Review of Materials Science · doi:10.1146/annurev.ms.07.080177.001323 · Cited by 2,194 · see citing works
Lithium niobate: Summary of physical properties and crystal structure
Weis, R. S., & Gaylord, T. K. (1985) · Applied Physics A Solids and Surfaces · doi:10.1007/bf00614817 · Cited by 1,868 · see citing works
A review of lithium niobate modulators for fiber-optic communications systems
Wooten, E. L., Kissa, K. M., Yi-Yan, A., Murphy, E. J., Lafaw, D. A., Hallemeier, P. F., Maack, D., Attanasio, D. V., Fritz, D. J., McBrien, G. J., et al. (2000) · IEEE Journal of Selected Topics in Quantum Electronics · doi:10.1109/2944.826874 · Cited by 1,330 · see citing works
Crystalline Oxides on Silicon: The First Five Monolayers
McKee, R. A., Walker, F. J., & Chisholm, M. F. (1998) · Physical Review Letters · doi:10.1103/physrevlett.81.3014 · Cited by 1,019 · see citing works
A structure zone diagram including plasma-based deposition and ion etching
Anders, A. (2009) · Thin Solid Films · doi:10.1016/j.tsf.2009.10.145 · Cited by 988 · see citing works
Measurement of the displacement field of dislocations to 0.03 Å by electron microscopy
Hÿtch, M., Putaux, J., & Pénisson, J. M. (2003) · Nature · doi:10.1038/nature01638 · Cited by 598 · see citing works
Large Pockels effect in micro- and nanostructured barium titanate integrated on silicon
Abel, S., Eltes, F., Ortmann, J. E., Messner, A., Castera, P., Wagner, T., Urbonas, D., Rosa, A., Gutierrez, A. M., Tulli, D., et al. (2019) · Nature Materials · doi:10.1038/s41563-018-0208-0 · Cited by 554 · see citing works
Self-citationA strong electro-optically active lead-free ferroelectric integrated on silicon
Abel, S., Stöferle, T., Marchiori, C., Rossel, C., Rossell, M. D., Erni, R., Caimi, D., Sousa, M., Chelnokov, A., Offrein, B. J., et al. (2013) · Nature Communications · doi:10.1038/ncomms2695 · Cited by 350 · see citing works
Active Silicon Integrated Nanophotonics: Ferroelectric BaTiO3 Devices
Xiong, C., Pernice, W. H. P., Ngai, J. H., Reiner, J. W., Kumah, D. P., Walker, F. J., Ahn, C., & Tang, H. X. (2014) · Nano Letters · doi:10.1021/nl404513p · Cited by 299 · see citing works
Dubourdieu, C., Bruley, J., Arruda, T. M., Posadas, A. B., Jordan‐Sweet, J., Frank, M. M., Cartier, E., Frank, D. J., Kalinin, S. V., Demkov, A. A., et al. (2013) · Nature Nanotechnology · doi:10.1038/nnano.2013.192 · Cited by 277 · see citing works
Self-citationReiner, J. W., Kolpak, A. M., Segal, Y., Garrity, K. F., Ismail‐Beigi, S., Ahn, C., & Walker, F. J. (2010) · Advanced Materials · doi:10.1002/adma.200904306 · Cited by 225 · see citing works
Eltes, F., Mai, C., Caimi, D., Kroh, M., Popoff, Y., Winzer, G., Petousi, D., Lischke, S., Ortmann, J. E., Czornomaz, L., et al. (2019) · Journal of Lightwave Technology · doi:10.1109/jlt.2019.2893500 · Cited by 208 · see citing works
Ferroelectric Epitaxial Thin Films for Integrated Optics
Wessels, B. W. (2007) · Annual Review of Materials Research · doi:10.1146/annurev.matsci.37.052506.084226 · Cited by 176 · see citing works
Mazet, L., Yang, S. M., Kalinin, S. V., Schamm‐Chardon, S., & Dubourdieu, C. (2015) · Science and Technology of Advanced Materials · doi:10.1088/1468-6996/16/3/036005 · Cited by 136 · see citing works
Zhao, T., Chen, F. W., Lü, H., et al. (2000) · Journal of Applied Physics · doi:10.1063/1.373007 · Cited by 121 · see citing works
Microstructure and ferroelectricity of BaTiO <sub>3</sub> thin films on Si for integrated photonics
Kormondy, K. J., Popoff, Y., Sousa, M., Eltes, F., Caimi, D., Rossell, M. D., Fiebig, M., Hoffmann, P., Marchiori, C., Reinke, M., et al. (2017) · Nanotechnology · doi:10.1088/1361-6528/aa53c2 · Cited by 111 · see citing works
Self-citationEpitaxial Oxides on Semiconductors: From Fundamentals to New Devices
Kumah, D. P., Ngai, J. H., & Kornblum, L. (2019) · Advanced Functional Materials · doi:10.1002/adfm.201901597 · Cited by 100 · see citing works
Srikant, V., Tarsa, E. J., Clarke, D. R., et al. (1995) · Journal of Applied Physics · doi:10.1063/1.358902 · Cited by 90 · see citing works
Role of Sputter Deposition Rate in Tailoring Nanogranular Gold Structures on Polymer Surfaces
Schwartzkopf, M., Hinz, A., Polonskyi, O., et al. (2017) · ACS Applied Materials & Interfaces · doi:10.1021/acsami.6b15172 · Cited by 79 · see citing works
Fabrication of rf-Sputtered Barium Titanate Thin Films
Pratt, I. H., & Firestone, S. (1971) · Journal of Vacuum Science and Technology · doi:10.1116/1.1316300 · Cited by 75 · see citing works
Integration of Functional Oxides with Semiconductors
Demkov, A. A., & Posadas, A. B. (2014) · Springer eBooks · doi:10.1007/978-1-4614-9320-4 · Cited by 74 · see citing works
Self-citationEffects of two-stage deposition on the structure and properties of heteroepitaxial BaTiO3 thin films
Towner, D. J., Ni, J., Marks, T. J., et al. (2003) · Journal of Crystal Growth · doi:10.1016/s0022-0248(03)01195-3 · Cited by 65 · see citing works
Epitaxial integration of BaTiO3 on Si for electro-optic applications
Guo, W., Posadas, A. B., & Demkov, A. A. (2021) · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films · doi:10.1116/6.0000923 · Cited by 62 · see citing works
Self-citationDeposition Profile of RF-Magnetron-Sputtered BaTiO3 Thin Films
Lee, N.-Y., Sekine, T., Itô, Y., et al. (1994) · Japanese Journal of Applied Physics · doi:10.1143/jjap.33.1484 · Cited by 59 · see citing works
Strain relaxation in single crystal SrTiO3 grown on Si (001) by molecular beam epitaxy
Choi, M., Posadas, A. B., Dargis, R., et al. (2012) · Journal of Applied Physics · doi:10.1063/1.3695998 · Cited by 56 · see citing works
Self-citationDesign rules for strong electro-optic materials
Hamze, A., Reynaud, M., Geler-Kremer, J., & Demkov, A. A. (2020) · npj Computational Materials · doi:10.1038/s41524-020-00399-z · Cited by 56 · see citing works
Self-citationControlling tetragonality and crystalline orientation in BaTiO3nano-layers grown on Si
Abel, S., Sousa, M., Rossel, C., Caimi, D., Rossell, M. D., Erni, R., Fompeyrine, J., & Marchiori, C. (2013) · Nanotechnology · doi:10.1088/0957-4484/24/28/285701 · Cited by 52 · see citing works
Epitaxial BaTiO3 thin films on MgO
Buchal, C., Beckers, L., Eckau, A., et al. (1998) · Materials Science and Engineering B · doi:10.1016/s0921-5107(98)00219-0 · Cited by 51 · see citing works
Lin, E. L., Posadas, A. B., Zheng, L., Ortmann, J. E., Abel, S., Fompeyrine, J., Lai, K., Demkov, A. A., & Ekerdt, J. G. (2019) · Journal of Applied Physics · doi:10.1063/1.5087571 · Cited by 39 · see citing works
Self-citationControl of Polar Orientation and Lattice Strain in Epitaxial BaTiO3 Films on Silicon
Lyu, J., Estandía, S., Gàzquez, J., Chisholm, M. F., Fina, I., Dix, N., Fontcuberta, J., & Sánchez, F. (2018) · ACS Applied Materials & Interfaces · doi:10.1021/acsami.8b07778 · Cited by 35 · see citing works
Photonic Crystal Waveguide Electro-Optic Modulator With a Wide Bandwidth
Li, J., Liu, Z., Tu, Y., et al. (2013) · Journal of Lightwave Technology · doi:10.1109/jlt.2013.2255025 · Cited by 34 · see citing works
High ferroelectric polarization in c -oriented BaTiO3 epitaxial thin films on SrTiO3/Si(001)
Ścigaj, M., Chao, C. H., Gàzquez, J., Fina, I., Moalla, R., Saint‐Girons, G., Chisholm, M. F., Herranz, G., Fontcuberta, J., Bachelet, R., et al. (2016) · Applied Physics Letters · doi:10.1063/1.4962836 · Cited by 34 · see citing works
Ridge waveguide using highly oriented BaTiO3 thin films for electro-optic application
Kim, I., Avrahami, Y., Socci, L., et al. (2014) · Journal of Asian Ceramic Societies · doi:10.1016/j.jascer.2014.05.002 · Cited by 28 · see citing works
Hsu, M. M., Thourhout, D. V., Pantouvaki, M., Meersschaut, J., Conard, T. S., Richard, O., Bender, H., Favia, P., Vila, M., Cid, R., et al. (2017) · Applied Physics Express · doi:10.7567/apex.10.065501 · Cited by 27 · see citing works
Critical thickness control by deposition rate for epitaxial BaTiO3 thin films grown on SrTiO3(001)
Kawai, M., Kan, D., Isojima, S., et al. (2007) · Journal of Applied Physics · doi:10.1063/1.2821915 · Cited by 26 · see citing works
Merckling, C., Korytov, M., Celano, U., Hsu, M. M., Neumayer, S. M., Jesse, S., & Gendt, S. D. (2019) · Journal of Vacuum Science & Technology A Vacuum Surfaces and Films · doi:10.1116/1.5082237 · Cited by 26 · see citing works
Structural studies of epitaxial BaTiO3 thin film on silicon
Wagué, B., Brubach, J., Niu, G., Dong, G., Dai, L., Roy, P., Saint‐Girons, G., Romeo, P. R., Robach, Y., & Vilquin, B. (2019) · Thin Solid Films · doi:10.1016/j.tsf.2019.137636 · Cited by 24 · see citing works
Wu, H. W., Aoki, T., Posadas, A. B., Demkov, A. A., & Smith, D. J. (2016) · Applied Physics Letters · doi:10.1063/1.4943135 · Cited by 22 · see citing works
Self-citationMicro-effects of resputtering due to negative ion bombardment of growing thin films
Kester, D. J., & Messier, R. F. (1993) · Journal of materials research/Pratt's guide to venture capital sources · doi:10.1557/jmr.1993.1938 · Cited by 21 · see citing works
Electro-optic response in epitaxially stabilized orthorhombic mm2 BaTiO3
Reynaud, M., Chen, P., Li, W., Paoletta, T., Kwon, S., Lee, D., Beskin, I. M., Posadas, A. B., Kim, M. J., Landis, C. M., et al. (2021) · Physical Review Materials · doi:10.1103/physrevmaterials.5.035201 · Cited by 20 · see citing works
Self-citationLow temperature growth of epitaxial ferroelectric BaTiO3
Shin, Y. J., Jiang, J., Jia, Y., Walker, F. J., & Ahn, C. (2021) · APL Materials · doi:10.1063/5.0046624 · Cited by 20 · see citing works
Mechanism of oxidation protection of the Si(001) surface by sub-monolayer Sr template
Fredrickson, K., Seo, H., & Demkov, A. A. (2016) · Journal of Applied Physics · doi:10.1063/1.4960575 · Cited by 18 · see citing works
Self-citationEdmondson, B. I., Kwon, S., Ortmann, J. E., Demkov, A. A., Kim, M. J., & Ekerdt, J. G. (2020) · Journal of the American Ceramic Society · doi:10.1111/jace.17291 · Cited by 18 · see citing works
Self-citationAmbriz-Vargas, F., Nouar, R., Bacar, Z. S., et al. (2015) · Thin Solid Films · doi:10.1016/j.tsf.2015.07.065 · Cited by 17 · see citing works
Three Dimensional Domain Structure in Epitaxial Barium Titanate Thin Films
Towner, D. J., Lansford, T. J., & Wessels, B. W. (2004) · Journal of Electroceramics · doi:10.1007/s10832-004-5081-3 · Cited by 17 · see citing works
Design and preparation of stress-free epitaxial BaTiO3polydomain films by RF magnetron sputtering
Zhang, W., Yuan, M., Wang, X., et al. (2012) · Science and Technology of Advanced Materials · doi:10.1088/1468-6996/13/3/035006 · Cited by 16 · see citing works
Electro-Optically Active Oxides on Silicon for Photonics
Abel, S., & Fompeyrine, J. (2016) · Materials and Energy/Materials and energy · doi:10.1142/9789814740487_0010 · Cited by 12 · see citing works
Qiao, L., & Bi, X. F. (2009) · Journal of Physics D Applied Physics · doi:10.1088/0022-3727/42/17/175508 · Cited by 10 · see citing works
Film thickness dependence of electro-optic effect in epitaxial BaTiO3 thin films
Qiu, J., Ding, J., Yuan, N., et al. (2011) · Solid State Communications · doi:10.1016/j.ssc.2011.06.022 · Cited by 10 · see citing works
Strain-driven domain structure control and ferroelectric properties of BaTiO3 thin films
Jimi, M., Ohnishi, T., Terai, K., et al. (2005) · Thin Solid Films · doi:10.1016/j.tsf.2004.10.058 · Cited by 8 · see citing works
Flagged first, then by citations
Cited by
Sorted by citations
Chelladurai, D., Kohli, M., Winiger, J., Moor, D., Messner, A., Fedoryshyn, Y., Eleraky, M., Liu, Y., Wang, H., & Leuthold, J. (2025) · Nature Materials · doi:10.1038/s41563-025-02158-1 · Cited by 73 · see citing works
Reynaud, M., Waqar, M., Du, C., Posadas, A. B., Pan, X., & Demkov, A. A. (2025) · Communications Materials · doi:10.1038/s43246-025-00908-x · Cited by 14 · see citing works
Self-citationEvolution of epitaxial BaTiO3 on SrTiO3-buffered Si: Phase field analysis
Li, W., Landis, C. M., & Demkov, A. A. (2022) · Journal of Applied Physics · doi:10.1063/5.0111188 · Cited by 8 · see citing works
Self-citationLead-Free Perovskite Thin Films with Tailored Pockels-Kerr Effects for Photonics
Ion, V., Teodorescu, V., Birjega, R., Dinescu, M., Mitterbauer, C., Alexandrou, I., Ghitiu, I., Craciun, F., & Scarisoreanu, N. D. (2023) · ACS Applied Materials & Interfaces · doi:10.1021/acsami.3c06499 · Cited by 4 · see citing works
Metal Oxide Thin Films for Advanced Photonic Applications
Stîngescu, M.-L., Șopronyi, M.-A., Antohe, Ș., & Scărișoreanu, N.-D. (2026) · Crystals · doi:10.3390/cryst16030164 · Cited by 2 · see citing works
- Authors
- Posadas, A. B., Park, H., Reynaud, M., Cao, W., Reynolds, J. D., Guo, W., Jeyaselvan, V., Beskin, I., Mashanovich, G. Z., Warner, J. H., & Demkov, A. A.
- Affiliations
- The University of Texas at Austin (US)
- Texas Materials Institute (US)
- University of Southampton (GB)
- Corresponding author
- Demkov, Alexander A.
- ORCID
- Venue
- ACS Applied Materials & Interfaces
- Publisher
- American Chemical Society (ACS)
- Published
- 2021-10-20
- Volume
- 13
- Issue
- 43
- Pages
- 51230-51244
- ISSN
- 1944-8244 (ISSN-L)
- 1944-8252
- OpenAlex
- W3205063861
- Cited by
- 75
- References
- 50
- Citations by year
- 2026: 19 · 2025: 22 · 2024: 16 · 2023: 12 · 2022: 6
- FWCI
- 2.58
- Type
- journal article
- Language
- en
- Open access
- closed
- Licence
- Locations
- ACS Applied Materials & Interfaces (publishedVersion)
- PubMed (publishedVersion)
- ePrints Soton (University of Southampton) (acceptedVersion)
- Funders
- Air Force Office of Scientific Research (FA9550-18-1-0053)
- Topics
- Physical Sciences › Materials Science › Materials Chemistry › Ferroelectric and Piezoelectric Materials
- Physical Sciences › Physics and Astronomy › Atomic and Molecular Physics, and Optics › Photorefractive and Nonlinear Optics
- Physical Sciences › Materials Science › Electronic, Optical and Magnetic Materials › Multiferroics and related materials
- Keywords
- RF magnetron sputtering, silicon photonics, electro-optic modulator, silicon-on-insulator substrates, lattice parameters, a-axis orientation, recrystallization, Pockels coefficient, Mach-Zehnder modulator, thick films, film growth rate
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
