Epitaxial growth of SrRuO3 thin films with different orientation by chemical solution deposition

doi:10.1016/j.jallcom.2016.04.290

Journal of Alloys and Compounds

Volume 682, 15 October 2016, Pages 154-159

https://doi.org/10.1016/j.jallcom.2016.04.290 Get rights and content

Highlights

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Different orientated epitaxial SRO thin films have prepared with the CSD method.
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Different microstructure and magnetization are observed in the derived SRO films.
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SRO (110) thin films display uniform grains, large magnetization and low resistivity.

Abstract

Epitaxial SrRuO₃ (SRO) thin films have been prepared on (100), (110), and (111) LaAlO₃ substrates by chemical solution deposition method, and the microstructures as well as the properties are investigated. The SRO (110) thin films display much more denser, homogeneous and well-connected grains. All the derived SRO thin films show a metallic behavior with low room-temperature resistivity (mΩ·cm). All derived SRO films are ferromagnetic at low temperatures showing different Curie temperature due to the different residual stain, and the SRO (110) film has the largest magnetization and coercivity due to the enhanced morphology. These results will provide a low-cost route to fabricate epitaxial SRO thin films with different orientation.

Introduction

As a member of a larger class of interesting ruthenates, perovskite SrRuO₃ (SRO) has been fascinatingly investigated more than several decades, due to its surprising itinerant ferromagnetism [1], unusual transport properties, and the degree and consequences of correlation. Beyond its rich physical properties, SRO has a pseudocubic structure with favorable unit cell parameter [2], [3], presents excellent structural compatibility with many perovskite-based oxides, which benefits preparing epitaxial multilayered structures of complex oxides. In addition, epitaxial SRO thin films on appropriate substrates have become the model system of choice for the study of its physical properties, and shows fascinating electrical and magnetic properties with different orientations.

Moreover, high metallic conductivity and temperature stability also make SRO thin film can be used as a bottom electrode and/or buffer layer to grow epitaxial functional thin films in many applications including dynamic and ferroelectric random-access memory [4], [5]. However, for some ferroelectric materials, their comparatively unspectacular ferroelectric properties only display in the films with a particular crystallographic orientation [6]. Thus, the requirements and investigations of SRO thin films grown in different directions on substrates are very important and desirable, not only for the functional films epitaxial growth on the SRO films, but also for recognizing the correlation between the orientation, microstructure and properties.

Additionally, enhanced magnetization has been reported in the epitaxial SRO thin films with different orientations grown on SrTiO₃ substrates prepared by pulsed laser deposition method [6]. However, in view of large-area fabrication and expense, low-cost and large-scale technique should be considered. Chemical solution deposition (CSD) method, as an effective route to fabricate multifunctional large-area thin films, possesses many advantages such as low-cost, easy manipulation and so on [7]. Herein, epitaxial SRO thin films on the (100), (110), and (111) LaAlO₃ (LAO) single crystal substrates were prepared by CSD method. The epitaxial growth, microstructures, electrical resistivity and magnetic properties of the (100), (110), and (111) SRO thin films were investigated.

Section snippets

Experimental procedure

SRO thin films were respectively prepared on (100), (110), and (111) LAO substrates by CSD method. Ru(NO)(NO₃)₃ (Ru, w/v = 1.5%) and Sr(CH₃COO)₂ 0.5H₂O (99%) were used as raw materials, and 2-methoxyethanol and glacial acetic acid were used as solvents to prepare the SrRuO₃ precursor solution. Firstly, Ru(NO)(NO₃)₃ was dissolved into 2-methoxyethanol and Sr(CH₃COO)₂. 0.5H₂O was dissolved in glacial acetic acid, respectively. Then, the two solutions were mixed and stirred for 6 h to obtain the

Result and discussion

Fig. 1 presents the XRD patterns of all derived SRO thin films. It is seen that all films are phase-pure without any detectable impurity phase such as RuO₂, which is usually found in SRO films [4], [8], [9]. In fact, in our early earlier researches, it has been found that the SRO can be derived below 700 °C, while, which shows poor crystallization quality. Over 700 °C, at around 800 °C, the impurity of RuO₂ can be observed in the derived SRO thin films. Thus, the annealing temperature of 700 °C

Conclusions

Epitaxial (100), (110), and (111) SRO thin films have been respectively prepared on the (100), (110), and (111) oriented LAO substrates by CSD method. The film SRO (111) exhibits the largest out-of-plane tensile stress. The film SRO (110) displays much denser, homogeneous and well connected grains with the smallest grain size. All the SRO thin films display metallic behavior with low electrical resistivity of 10⁻⁴ Ω cm at room-temperature, and then become semiconducting at the temperature below

Acknowledgments

This work was supported by the National NSFC (Nos. 11174288, 11204316 and 11374304), the Joint Funds of the National NSFC and the CAS’ Large-Scale Scientific Facility (Nos. U1432137 and U1232210).

References (32)

O. Morán et al.
Observation of possible quantum interference effects in SrRuO₃ epitaxial thin films grown by high-oxygen pressure dc sputtering
Solid State Sci.
(2010)
S. Yamada et al.
Characterization of an epitaxial CaRuO₃ film prepared via the sol-gel route
Thin Solid Films
(2005)
H. Suzuki et al.
Chemical solution deposition of conductive SrRuO₃ thin film on Si substrate
Ceram. Int.
(2004)
R. Seveno et al.
Elaboration of strontium ruthenium oxide thin films on metal substrates by chemical solution deposition
Thin Solid Films
(2005)
D. Rubi et al.
Growth of flat SrRuO₃ (111) thin films suitable as bottom electrodes in heterostructures
Thin Solid Films
(2009)
J. Chang et al.
Layer-by-layer growth and growth-mode transition of SrRuO₃ thin films on atomically flat single-terminated SrTiO₃ (111) surfaces
J. Cryst. Growth Des.
(2009)
O. Morán et al.
Aspects of “low field” magnetotransport in epitaxial thin films of the ferromagnetic metallic oxide SrRuO₃
Phys. B
(2007)
O. Morán et al.
Possible occurrence of transition from a Fermi- to a non-Fermi-liquid behavior in epitaxial SrRuO₃ thin films
Superlattices Microstruct.
(2013)
J.J. Neumeier et al.
Influence of pressure on the ferromagnetic transition temperature of SrRuO₃
Phys. B
(1994)
M. Shikano
Pressure dependence of the magnetic transition temperature for ferromagnetic SrRuO₃
Solid State Commun.
(1994)

J.J. Randall et al.

The preparation of some terhary oxides of the platinum metals

J. Am. Chem. Soc.

(1959)

G. Koster et al.

Structure, physical properties, and applications of SrRuO₃ thin films

Rev. Mod. Phys.

(2012)

M. Narayanan et al.

Sol−Gel synthesis of high-quality SrRuO₃ thin-film electrodes suppressing the formation of detrimental RuO₂ and the dielectric properties of integrated lead lanthanum zirconate titanate films

Chem. Mater

(2011)

X.K. Ning et al.

Anisotropy of electrical and magnetic transport properties of epitaxial SrRuO₃ thin films

J. Appl. Phys.

(2015)

G. Subramanyam et al.

Challenges and opportunities for multi-functional oxide thin films for voltage tunable radio frequency/microwave components

J. Appl. Phys.

(2013)

A. Ito et al.

Microstructure and electrical conductivity of epitaxial CaRuO₃ thin films prepared on (001), (110), (111) SrTiO₃ substrates by laser ablation

J. Ceram. Soc. Jpn.

(2007)

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View full text

Epitaxial growth of SrRuO3 thin films with different orientation by chemical solution deposition

Highlights

Abstract

Introduction

Section snippets

Experimental procedure

Result and discussion

Conclusions

Acknowledgments

Solid State Sci.

Thin Solid Films

Ceram. Int.

Thin Solid Films

Thin Solid Films

J. Cryst. Growth Des.

Phys. B

Superlattices Microstruct.

Phys. B

Solid State Commun.

The preparation of some terhary oxides of the platinum metals

J. Am. Chem. Soc.

Structure, physical properties, and applications of SrRuO3 thin films

Rev. Mod. Phys.

Sol−Gel synthesis of high-quality SrRuO3 thin-film electrodes suppressing the formation of detrimental RuO2 and the dielectric properties of integrated lead lanthanum zirconate titanate films

Chem. Mater

Anisotropy of electrical and magnetic transport properties of epitaxial SrRuO3 thin films

J. Appl. Phys.

Challenges and opportunities for multi-functional oxide thin films for voltage tunable radio frequency/microwave components

J. Appl. Phys.

Microstructure and electrical conductivity of epitaxial CaRuO3 thin films prepared on (001), (110), (111) SrTiO3 substrates by laser ablation

J. Ceram. Soc. Jpn.

Epitaxial growth of SrRuO₃ thin films with different orientation by chemical solution deposition

Structure, physical properties, and applications of SrRuO₃ thin films

Sol−Gel synthesis of high-quality SrRuO₃ thin-film electrodes suppressing the formation of detrimental RuO₂ and the dielectric properties of integrated lead lanthanum zirconate titanate films

Anisotropy of electrical and magnetic transport properties of epitaxial SrRuO₃ thin films

Microstructure and electrical conductivity of epitaxial CaRuO₃ thin films prepared on (001), (110), (111) SrTiO₃ substrates by laser ablation