Seeded Lateral Solid-Phase Crystallization of the Perovskite Oxide SrTiO₃

Journal Article · Wed Feb 27 00:00:00 EST 2019 · Journal of Physical Chemistry. C

DOI:https://doi.org/10.1021/acs.jpcc.9b00078· OSTI ID:1510079

Chen, Yajin ^[1]; Tilka, Jack A. ^[1]; Ahn, Youngjun ^[1]; Park, Joonkyu ^[1]; Pateras, Anastasios ^[1]; Zhou, Tao ^[2]; Savage, Donald E. ^[1]; McNulty, Ian ^[3]; Holt, Martin V. ^[3]; Paskiewicz, Deborah M. ^[3]; Fong, Dillon D. ^[3]; Kuech, Thomas F. ^[1]; Evans, Paul G.  ^[1]

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1. Univ. of Wisconsin, Madison, WI (United States)
2. European Synchrotron Radiation Facility (ESRF), Grenoble (France)
3. Argonne National Lab. (ANL), Argonne, IL (United States)

Crystallization from an amorphous precursor presents a new route to control the properties of complex oxides by selecting their nanoscale morphology. A key challenge in crystal growth from the amorphous form is to select the locations of nucleation and the crystallographic orientation of the resulting crystals. Nucleation sites for crystallization of the prototypical perovskite complex oxide SrTiO₃ (STO) from its amorphous form can be reproducibly introduced using nanoscale seed crystals. The results of two seeding strategies are reported here: (i) SrRuO₃ (SRO) (001)-oriented nanomembranes and (ii) STO nanocrystalline seeds. Amorphous STO crystallizes laterally over distances of several microns from the seeds before encountering separately nucleated crystals. The lateral crystallization rates for both types of seeding methods are close to the values measured in solidphase epitaxy (SPE) of STO on single-crystal substrates. The lateral crystallization distances along different crystallographic orientations are equal, indicating that the lateral crystallization rate is isotropic. The isotropic crystallization suggests that the rate-limiting steps for crystallization occur within the amorphous STO away from the amorphous/crystalline interface. In addition to the lateral crystallization, STO crystallizes on top of the planar SRO nanomembrane seeds via SPE, forming partially relaxed [001]-oriented heteroepitaxial STO layers. The in-plane orientation of laterally crystallized STO near the SRO nanomembrane seeds exhibits overall polycrystallinity with regions in which micron-scale grains of laterally crystallized STO share the same in-plane orientation as the SRO nanomembrane seeds. Crystallization from seed crystals provides opportunities to create a wide range of other perovskite oxides in nanoscale geometries.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1510079
• Journal Information: Journal of Physical Chemistry. C, Vol. 123, Issue 12; ISSN 1932-7447
• Publisher: American Chemical Society
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
SrTiO3
complex oxide
crystal seeds
lateral solid-phase crystallization
nanocrystal
solid-phase epitaxy