Epitaxial Stabilization of Single-Crystal Multiferroic YCrO3 Thin Films

We report on the growth of stoichiometric, single-crystal YCrO3 epitaxial thin films on (001) SrTiO3 substrates using pulsed laser deposition. X-ray diffraction and atomic force microscopy reveal that the films grew in a layer-by-layer fashion with excellent crystallinity and atomically smooth surfaces. Magnetization measurements demonstrate that the material is ferromagnetic below 144 K. The temperature dependence of dielectric permittivity shows a characteristic relaxor-ferroelectric behavior at TC = 375–408 K. A dielectric anomaly at the magnetic transition temperature indicates a close correlation between magnetic and electric order parameters in these multiferroic YCrO3 films. These findings provide guidance to synthesize rare-earth, chromite-based multifunctional heterostructures and build a foundation for future studies on the understanding of magnetoelectric effects in similar material systems.

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Fabrication,Transport and Raman Studies of Pulsed Laser Deposited Al/Ga Doped PBCO Thin Films

MRS Proceedings ◽

10.1557/proc-1222-dd02-09 ◽

2009 ◽

Vol 1222 ◽

Author(s):

Hom R Kandel ◽

Tar-Pin Chen ◽

Hye-Won Seo ◽

Milko Iliev ◽

Paritosh Wadekar ◽

...

Keyword(s):

Thin Films ◽

Single Crystal ◽

Epitaxial Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Micro Raman Spectroscopy ◽

Atomic Force ◽

Second Phases ◽

Krf Excimer Laser

AbstractWe have fabricated highly resistive materials PrBa2 (Cu1-xMx) 3O7 (M=Al, Ga, x = 0.20) by doping metals Ga and Al on PrBa2Cu3O7(PBCO). X-ray data indicated no significant second phases in substituting Cu by Al or Ga up to 20%.The electrical resistivity of these materials were three to four orders in magnitude higher than PBCO at 200K, which may give an effective potential barrier to YBCO in high Tc S-I-S Josephson junction. Epitaxial thin films of these materials were grown using KrF excimer laser on LAO (110) single crystal substrates. X-ray diffraction (XRD) and atomic force microscopy (AFM) were deployed to study the crystal orientation, epitaxy and roughness of the single crystal thin films. Micro Raman spectroscopy was carried out to investigate the dopant site in PBCO.

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Two conductive mechanisms in LaMnO3 thin film: Adiabatic and nonadiabatic small polaronic hopping

Modern Physics Letters B ◽

10.1142/s0217984921503103 ◽

2021 ◽

pp. 2150310

Author(s):

Weiyuan Wang ◽

Jiyu Fan ◽

Huan Zheng ◽

Jing Wang ◽

Hao Liu ◽

...

Keyword(s):

Thin Films ◽

Theoretical Models ◽

Magnetic Phase Transitions ◽

Epitaxial Thin Films ◽

X Ray Diffraction ◽

Epitaxial Relationship ◽

Reciprocal Space Mapping ◽

Force Microscopy ◽

Atomic Force ◽

Out Of Plane

We have presented the structural, surface morphology, magnetic and resistivity data for perovskite LaMnO3 epitaxial thin films which are fabricated on well-oriented (001) LaAlO3 substrates by pulsed laser deposition technique. X-ray diffraction [Formula: see text]–[Formula: see text] linear scans and reciprocal space mapping measurement confirm that the out-of-plane and in-plane epitaxial relationship are LMO(001)/LAO(001) and LMO(110)/LAO(110), respectively. Surface roughness determined by atomic force microscopy was no more than 0.3 nm. In the whole studied temperature range, all films only show a paramagnetic behavior instead of any magnetic phase transitions. Correspondingly, the electron transport behaviors always exhibit an insulting state as the temperature changes from high to low. However, we find that none of theoretical models can individually be used to understand their conductive mechanisms. Further studies indicated that charge carries of high and low temperature region obey adiabatic and nonadiabatic small polaronic hopping mechanisms, respectively. This finding offers new ways of exploiting the abnormal ferromagnetism in LaMnO3 multilayer thin films.

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Dielectric and Electromechanical Behaviour of Relaxor [(1−x)Pb(Mg1/3Nb2/3)O3 -xPbTiO3] Thin Films

MRS Proceedings ◽

10.1557/proc-688-c10.2.1 ◽

2001 ◽

Vol 688 ◽

Author(s):

N.J. Donnelly ◽

G. Catalan ◽

C. Morros ◽

R.M. Bowman ◽

J.M. Gregg

Keyword(s):

Thin Films ◽

Single Crystal ◽

Plane Strain ◽

X Ray Diffraction ◽

Force Microscopy ◽

Bulk Ceramic ◽

Atomic Force ◽

Out Of Plane ◽

Order Of Magnitude

AbstractThin film capacitor structures of Au / (1−x)Pb(Mg1/3Nb2/3)O3 - xPbTiO3 /(La1/2Sr1/2)CoO3 were fabricated by pulsed laser deposition on single crystal {001} MgO substrates. Films were found to be perovskite dominated and highly {001} oriented. Dielectrically, films displayed relaxorlike features, though maximum permittivity was low compared to single crystal or bulk ceramic (∼1400 at peak @1kHz, for x=0.07, 0.1 & 0.2). A field induced piezoelectric coefficient d33 was measured by piezoresponse atomic force microscopy for specific compositions x =0, × =0.07, and x =0.1 and found to be disappointingly low - indicating poor electric field induced strain. Despite this macroscopic electrostrictive coefficients Q33 were found to be (3.6 ± 0.6) ×10−2C−2m4, (2.6 ± 0.2) ×10−2C−2m4, and (0.9 ± 0.3) ×10−2C−2m4 respectively. Crystallographic electrostrictive coefficients were determined by in-situ x-ray diffraction and found to be (4.9 ± 0.2) ×10−2C−2m4 for PMN-(0.07)PT and (1.9 ± 0.1) ×10−2C−2m4 for PMN-(0.1)PT. Considering that all these Q33 values are of the same order of magnitude as found in single crystal experiments (2.5 – 3.8 ×10−2C−2m4), it is suggested that low out-of-plane strain is entirely a result of reduced polarisability rather than reduced electrostrictive coefficients in thin films relative to bulk ceramic or single crystal. An estimate was also made of the Q13 electrostrictive coefficient for PMN and PMN-(0.07)PT by measuring permittivity as a function of applied in-plane strain. The values obtained were -1.31 ×10−2C−2m4 and -0.46 ×10−2C−2m4 respectively.

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The Effect of Miscut Angle and Miscut Direction of Vicinal (001) SrTiO3 Substrates on The Domain Structure of Epitaxial SrRuO3 Thin Films

MRS Proceedings ◽

10.1557/proc-474-259 ◽

1997 ◽

Vol 474 ◽

Cited By ~ 1

Author(s):

Q. Gan ◽

R. A. Rao ◽

C.B Eom

Keyword(s):

Thin Films ◽

Domain Structure ◽

Epitaxial Thin Films ◽

X Ray Diffraction ◽

Orthorhombic Unit Cell ◽

Metallic Oxide ◽

Force Microscopy ◽

Atomic Force ◽

Step Flow Growth ◽

Miscut Angle

ABSTRACTWe have grown epitaxial thin films of isotropie metallic oxide SrRuC>3 on both exact and vicinal (001) SrTiO3 substrates with miscut angle (α) up to 5.0° and miscut direction (β) up to 37° away from the in-plane [010] axis. The effects of both α and β on the epitaxial growth and domain structure of epitaxial SrRuC>3 thin films were studied by x-ray diffraction and atomic force microscopy (AFM). On vicinal SrTiO3 substrates with a large miscut angle (α = 1.7°, 2.0°, 4.1°, and 5.0°) and miscut direction close to the [010] axis, single crystal epitaxial (110)° SrRuO3 thin films were obtained. [The superscript o refers to the Miller indices based on the orthorhombic unit cell.] Decreasing the substrate miscut angle or aligning the miscut direction close to the [110] axis (β = 45°) resulted in an increase of 90° domains in the plane. The films grown on vicinal substrates displayed a significant improvement in crystalline quality and in-plane epitaxial alignment as compared to the films grown on exact (001) SrTiO3 substrates. AFM revealed that as the miscut angle increased the growth mechanism changed from two dimensional nucleation to step flow growth.

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Structural and Surface Morphology Changes in CuInSe2 Thin Films as a Function of Cu/In Ratio

MRS Proceedings ◽

10.1557/proc-441-9 ◽

1996 ◽

Vol 441 ◽

Author(s):

P. Fons ◽

S. Niki ◽

A. Yamada ◽

D. J. Tweet

Keyword(s):

Thin Films ◽

Molecular Beam ◽

Morphological Changes ◽

Epitaxial Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

The Ideal

AbstractDue to its high near bandedge absorption, CuInSe2 is considered to be one of the most promising solar cell materials. As CuInSe2 films are usually grown by metastable processes, the Cu/In ratio often deviates from the ideal ratio of unity. To investigate the structural and morphological changes induced by such stoichiometric variations we have grown a series of epitaxial CuInSe2 epitaxial thin films with varying Cu/In ratios by molecular beam epitaxy on GaAs(001) substrates from elemental sources at a growth temperature of 450° C. Overall structural, microstructural and surface morphological changes were observed by X-ray diffraction, transmission electron microscopy, and atomic force microscopy, respectively. It was observed that as films deviated from stoichiometry, twinning occurred preferentially on the anion {1 · 1 · 2} planes.

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Investigation of Growth Evolution in c-Axis SrBi2Nb2O9 Epitaxial Thin Films

MRS Proceedings ◽

10.1557/proc-574-31 ◽

1999 ◽

Vol 574 ◽

Cited By ~ 1

Author(s):

J. Lettieri ◽

M. A. Zurbuchen ◽

G. W. Brown ◽

Y. Jia ◽

W. Tian ◽

...

Keyword(s):

Thin Films ◽

Rutherford Backscattering Spectrometry ◽

Growth Conditions ◽

Layer Growth ◽

Spiral Growth ◽

Layer By Layer ◽

Epitaxial Thin Films ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron

Abstract(001)-oriented epitaxial SrBi2Nb2O9 thin films have been grown by pulsed laser deposition on (001) SrTiO3 and (001) LaAlO3—Sr2AlTaO6 substrates at optimized growth conditions. 4-circle x-ray diffraction, Rutherford backscattering spectrometry, and transmission electron microscopy reveal highly oriented epitaxial films. Atomic force microscopy indicates spiral growth for films grown on SrTiO3 and layer-by-layer growth for films grown on LaAlO3—Sr2AlTaO6.

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Structural Control of Epitaxially Grown Sputtered Perovskite Thin Films

MRS Proceedings ◽

10.1557/proc-401-151 ◽

1995 ◽

Vol 401 ◽

Cited By ~ 9

Author(s):

Kiyotaka Wasa ◽

Toshifumi Sato ◽

Hideaki Adachi ◽

Kentaro Setsune ◽

S. Trolier-McKinstry ◽

...

Keyword(s):

Thin Films ◽

Single Crystal ◽

Structural Control ◽

Film Growth ◽

Substrate Surface ◽

Epitaxial Films ◽

Crystal Phase ◽

X Ray Diffraction ◽

Force Microscopy ◽

Atomic Force

AbstractThin films of perovskite Pb–Ti–O3 families were heteroepitaxially grown by sputtering on (0001)sapphire and/or (001)SrTiO (ST). These epitaxial films contained microstructures, although X–ray diffraction analysis suggested formation of single crystal phase with three dimentional crystal orientation. Their microstructures were studied by the electron microscopy, atomic force microscopy, and spectroscopic ellipsometry so as to find factors which influence the formation of the microstructure. It was found that the orientation of the substrate surface and the chemical composition of adatoms during initial film growth strongly affected the formation of the microstructures. Sputtered PbTiO3 (PT) thin films under a stoichiometric condition on a miscut(001) ST(miscut 1.7 degree) realized the growth of continuous single crystal thin films of 10–100nm thick with extremely smooth surface with surface roughness less than 3nm. Deposition on a miscut substrate under a stoichiometric condition is essential to make continuous thin films of perovskite of single crystal phase.

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Nanocrystalline Solutions as Precursors to The Spray Deposition of Cdte Thin Films

MRS Proceedings ◽

10.1557/proc-382-461 ◽

1995 ◽

Vol 382 ◽

Cited By ~ 4

Author(s):

Martin Pehnt ◽

Douglas L. Schulz ◽

Calvin J. Curtis ◽

Helio R. Moutinho ◽

Amy Swartzlander ◽

...

Keyword(s):

Thin Films ◽

Atomic Force Microscopy ◽

Grain Size ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Cdte Nanoparticles ◽

Atomic Force ◽

Vis Spectroscopy ◽

Cdte Thin Films

ABSTRACTIn this article we report the first nanoparticle-derived route to smooth, dense, phase-pure CdTe thin films. Capped CdTe nanoparticles were prepared by injection of a mixture of Cd(CH3)2, (n-C8H17)3 PTe and (n-C8H17)3P into (n-C8H17)3PO at elevated temperatures. The resultant nanoparticles 32-45 Å in diameter were characterized by x-ray diffraction, UV-Vis spectroscopy, transmission electron microscopy, thermogravimetric analysis and energy dispersive x-ray spectroscopy. CdTe thin film deposition was accomplished by dissolving CdTe nanoparticles in butanol and then spraying the solution onto SnO2-coated glass substrates at variable susceptor temperatures. Smooth and dense CdTe thin films were obtained using growth temperatures approximately 200 °C less than conventional spray pyrolysis approaches. CdTe films were characterized by x-ray diffraction, UV-Vis spectroscopy, atomic force microscopy, and Auger electron spectroscopy. An increase in crystallinity and average grain size as determined by x-ray diffraction was noted as growth temperature was increased from 240 to 300 °C. This temperature dependence of film grain size was further confirmed by atomic force microscopy with no remnant nanocrystalline morphological features detected. UV-Vis characterization of the CdTe thin films revealed a gradual decrease of the band gap (i.e., elimination of nanocrystalline CdTe phase) as the growth temperature was increased with bulk CdTe optical properties observed for films grown at 300 °C.

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Studies of Nanomechanical Properties of Pulsed Laser Deposited NbN films on Si Using Nanoindentation

MRS Proceedings ◽

10.1557/opl.2012.152 ◽

2012 ◽

Vol 1424 ◽

Author(s):

M. A. Mamun ◽

A. H. Farha ◽

Y. Ufuktepe ◽

H. E. Elsayed-Ali ◽

A. A. Elmustafa

Keyword(s):

Thin Films ◽

Pulsed Laser ◽

Niobium Nitride ◽

X Ray Diffraction ◽

Si Substrate ◽

Force Microscopy ◽

Atomic Force ◽

Wide Range ◽

Pile Up ◽

Average Modulus

ABSTRACTNanomechanical and structural properties of pulsed laser deposited niobium nitride thin films were investigated using X-ray diffraction, atomic force microscopy, and nanoindentation. NbN film reveals cubic δ-NbN structure with the corresponding diffraction peaks from the (111), (200), and (220) planes. The NbN thin films depict highly granular structure, with a wide range of grain sizes that range from 15-40 nm with an average surface roughness of 6 nm. The average modulus of the film is 420±60 GPa, whereas for the substrate the average modulus is 180 GPa, which is considered higher than the average modulus for Si reported in the literature due to pile-up. The hardness of the film increases from an average of 12 GPa for deep indents (Si substrate) measured using XP CSM and load control (LC) modes to an average of 25 GPa measured using the DCM II head in CSM and LC modules. The average hardness of the Si substrate is 12 GPa.

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Influence of the growth parameters of TiO2 thin films deposited by the MOCVD method

Cerâmica ◽

10.1590/s0366-69132002000100009 ◽

2002 ◽

Vol 48 (305) ◽

pp. 38-42 ◽

Cited By ~ 3

Author(s):

M. I. B. Bernardi ◽

E. J. H. Lee ◽

P. N. Lisboa-Filho ◽

E. R. Leite ◽

E. Longo ◽

...

Keyword(s):

Thin Films ◽

Growth Parameters ◽

Structural Characteristics ◽

Chemical Vapor ◽

X Ray Diffraction ◽

Tio2 Thin Films ◽

X Ray ◽

Force Microscopy ◽

Atomic Force ◽

Deposition Parameters

The synthesis of TiO2 thin films was carried out by the Organometallic Chemical Vapor Deposition (MOCVD) method. The influence of deposition parameters used during growth on the final structural characteristics was studied. A combination of the following experimental parameters was studied: temperature of the organometallic bath, deposition time, and temperature and substrate type. The high influence of those parameters on the final thin film microstructure was analyzed by scanning electron microscopy with electron dispersive X-ray spectroscopy, atomic force microscopy and X-ray diffraction.

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