Properties of the magnetoresistive La0.8Sr0.2MnO3 film and integration with PbZr0.52 Ti0.48O3 ferroelectrics

AbstractThe colossal magnetoresistive La0.8Sr0.2MnO3 (LSMO) thin film was prepared on the MgO (100) single crystal substrate using KrF excimer pulsed laser deposition technique. The LSMO film deposited at the substrate temperature of 850 °C, oxygen pressure of 500 mTorr and laser energy density of 2 J/cm2(5 Hz) showed the resistivity peak temperature (Tp) of 330 K and the magnetoresi stance change of 15 %(H=0.7 T) at the room temperature. The large lattice mismatch with the substrate increased Tp and decreased the resistivity of the LSMO film.The X-ray diffraction measurement for the PbZr0.52Ti0.48O3 (PZT) / LSMO heterostructures indicated both c-axis and in- plane orientation, with the good PZT surface morphology.

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Preparation and Characterization of CdSxTe1−x Alloys and Films

MRS Proceedings ◽

10.1557/proc-668-h5.21 ◽

2001 ◽

Vol 668 ◽

Cited By ~ 3

Author(s):

R.G. Dhere ◽

D.S. Albin ◽

S.E. Asher ◽

H.R. Moutinho ◽

D. Compton ◽

...

Keyword(s):

High Efficiency ◽

Lattice Mismatch ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Alloy Films ◽

Present Generation ◽

Large Lattice ◽

Large Lattice Mismatch ◽

Post Deposition

ABSTRACTIntermixing at the CdS/CdTe interface is considered crucial for the performance of CdTe-based solar cells. High-efficiency devices have been fabricated in spite of large lattice mismatch between CdS and CdTe. Intermixing and formation of CdSxTe1−x alloys in present-generation devices result from high-temperature CdTe deposition and post-deposition CdCl2 treatment. In this paper, we present our work on preparation of CdSxTe1−x-alloy powders and films. In this process, the CdS and CdTe powders are sized and mixed, isostatically pressed into a bar, sealed into closed-quartz ampoules, annealed at temperatures >1000°C, and water quenched. X-ray diffraction (XRD) analysis showed that they contained only distinct phases on S-rich and Te-rich sides of the phase diagram. Recently, two new batches of CdSxTe1−x material, produced by an improved process have been obtained (x =0.71 and x= 0.35 in CdSxTe1−x alloy). Initial XRD results from the films deposited by close spaced sublimation (CSS) using these powders reveal that both samples of bulk powders (prior to CSS deposition) are single-phase and demonstrate CdS-like characteristics (hexagonal). We have deposited CdSxTe1−x-alloy films using these powders. These alloy powders evaporate more congruently as opposed to mixed powders of CdS and CdTe. We will also present results on the structural properties of thin CdSxTe1−x alloy films deposited using these powders by CSS.

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Self-Assembled BaTiO3-MnZnFe2O4Nanocomposite Films

Advances in Materials Science and Engineering ◽

10.1155/2012/109856 ◽

2012 ◽

Vol 2012 ◽

pp. 1-5

Author(s):

Guo Yu ◽

Feiming Bai ◽

Huaiwu Zhang

Keyword(s):

Remanent Polarization ◽

Lattice Mismatch ◽

Nanocomposite Films ◽

X Ray Diffraction ◽

Mnzn Ferrite ◽

Large Lattice ◽

Out Of Plane ◽

Large Lattice Mismatch ◽

Plane Direction ◽

Self Assembled

Self-assembled nanocomposite BaTiO3-Mn0.4Zn0.87Fe2O4magnetodielectric films have been grown on (001)-oriented SrTiO3substrates by a pulsed laser deposition method. High resolution X-ray diffraction shows that both BaTiO3and MnZn-ferrite phases are epitaxial along the out-of-plane direction with a 0–3 composite structure in spite of very large lattice mismatch. The magnetic, ferroelectric, and dielectric properties of the nanocomposite films are reported. A saturated magnetization of 330 emu/cc and double remanent polarization of 40 μC/cm2were obtained. Structural and compositional factors limiting the effective permeability and the dielectric constant will be discussed.

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Structural Effects in Al(111)/Si(111) Heteroepitaxy by Partially Ionized Beam Deposition α

MRS Proceedings ◽

10.1557/proc-116-485 ◽

1988 ◽

Vol 116 ◽

pp. 465-470 ◽

Cited By ~ 3

Author(s):

A. S. Yapsir ◽

C.-H. Choi ◽

S. N. Yang ◽

T.-M. Lu ◽

M. Madden ◽

...

Keyword(s):

Single Crystal ◽

Lattice Mismatch ◽

X Ray Diffraction ◽

Tem Analysis ◽

Atom Ratio ◽

Transmission Electron ◽

Large Lattice ◽

Large Lattice Mismatch ◽

Partially Ionized ◽

Acceleration Voltage

AbstractSingle crystal Al(111) films were grown on Si(111) surface at room temperature under a conventional vacuum condition using the partially ionized beam (PIB) deposition technique. The Al films were deposited with an ion to atom ratio of about 0.3% and an acceleration voltage of 1 kV. Transmission electron microscopy (TEM) analysis showed that the as-deposited films were single crystal with certain density of dislocation networks. These dislocations disappeared following a heat treatment at 450°C for 30 min. From X-ray diffraction and TEM patterns, it was observed that the Al(111) was aligned to the substrate with Al<1l0>//Si<1l0>. Possible mechanisms of the PIB epitaxial growth and a novel structural defect that is unique to this large lattice mismatch system are discussed.

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Heteroepitaxial growth and structural analysis of epitaxial α–Fe2O3(1010) on TiO2(001)

Journal of Materials Research ◽

10.1557/jmr.2005.0164 ◽

2005 ◽

Vol 20 (5) ◽

pp. 1250-1256 ◽

Cited By ~ 3

Author(s):

Joshua R. Williams ◽

Chongmin Wang ◽

Scott A. Chambers

Keyword(s):

Lattice Mismatch ◽

High Energy ◽

Unit Cell ◽

Heteroepitaxial Growth ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Pole Figures ◽

Large Lattice ◽

Large Lattice Mismatch

We grew epitaxial α–Fe2O3(1010) on TiO2(001) rutile by oxygen plasma-assisted molecular-beam epitaxy. High-resolution transmission electron microscopy (HRTEM), reflection high-energy electron diffraction (RHEED), and x-ray diffraction pole figures confirm that the film is composed of four different in-plane orientations rotated by 90° relative to one another. For a given Fe2O3 unit cell, the lattice mismatch along the parallel [0001]Fe2O3 and [100]TiO2 directions is nominally +67%. However, due to a 3-fold repetition of the slightly distorted square symmetry of anion positions within the Fe2O3 unit cell, there is a coincidental anion alignment along the [0001]Fe2O3 and [100]TiO2 directions, which results in an effective lattice mismatch of only −0.02% along this direction. The lattice mismatch is nearly 10% in the orthogonal [1120]Fe2O3 and [100]TiO2 directions. The film is highly ordered and well registered to the substrate despite a large lattice mismatch in one direction. The film grows in registry with the substrate along the parallel [0001]Fe2O3 and [100]TiO2 directions and nucleates dislocations along the orthogonal [1120]Fe2O3 [100]TiO2 directions.

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Epitaxial Dielectric Planarization for Multilayer HTSC Structures

MRS Proceedings ◽

10.1557/proc-341-151 ◽

1994 ◽

Vol 341 ◽

Author(s):

Bertha P. Chang ◽

Paul C. Mcintyre ◽

Neville Sonnenberg ◽

Michael J. Cima

Keyword(s):

Lattice Mismatch ◽

Ion Beam ◽

Thick Layer ◽

Normal Incidence ◽

X Ray Diffraction ◽

Ion Beam Assisted Deposition ◽

Surface Steps ◽

Large Lattice ◽

Large Lattice Mismatch ◽

Planarization Process

AbstractYttria-stabilized ZrO2 (YSZ) and CeO2 thin films were deposited on patterned (001) YSZ and (001) LaAIO3 substrates, respectively, using ion beam assisted deposition (IBAD) at normal incidence and an ion beam energy of 500eV. All deposition took place at 600°C. An initial 1000Å thick layer was evaporated at 0.2Å/s before beginning IBAD at rates of 0.3Å/s for YSZ and between 0.8Å/s and 1.2Å/s for CeO2. X-ray diffraction shows the YSZ films to grow epitaxially. The planarization mechanism for IBAD YSZ is similar to that previously observed for if-bias sputtering. CeO2 grows epitaxially on LaA103 but a second polycrystalline phase grows preferentially over the surface steps and inhibits the planarization process. The emergence of this phase appears to be related to highly incoherent growth of CeO2 over the stepped edges, which in turn is a function of the large lattice mismatch between CeO2 and LaA1O3 in the [001] direction.

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Enhanced luminescence/photodetecting bifunctional devices based on ZnO:Ga microwire/p-Si heterojunction by incorporating Ag nanowires

Nanoscale Advances ◽

10.1039/d1na00428j ◽

2021 ◽

Author(s):

Mingming Jiang ◽

Yang Liu ◽

Ruiming Dai ◽

Kai Tang ◽

Peng Wan ◽

...

Keyword(s):

Band Gap ◽

Carrier Mobility ◽

Lattice Mismatch ◽

Semiconductor Materials ◽

Large Lattice ◽

Ag Nanowires ◽

Large Lattice Mismatch ◽

Enhanced Luminescence ◽

Indirect Band Gap

Suffering from the indirect band gap, low carrier mobility, and large lattice mismatch with other semiconductor materials, one of the current challenges in Si-based materials and structures is to prepare...

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An X-ray scattering study on inverted Ge–Si huts grown at low temperatures

Powder Diffraction ◽

10.1154/1.1815339 ◽

2004 ◽

Vol 19 (4) ◽

pp. 347-351

Author(s):

J. Xu ◽

X. S. Wu ◽

B. Qian ◽

J. F. Feng ◽

S. S. Jiang ◽

...

Keyword(s):

Low Temperatures ◽

Lattice Strain ◽

Lattice Mismatch ◽

Grazing Incidence ◽

X Ray Diffraction ◽

X Ray ◽

X Ray Scattering ◽

Transmission Electron ◽

Large Lattice ◽

Scattering Study

Ge–Si inverted huts, which formed at the Si∕Ge interface of Si∕Ge superlattice grown at low temperatures, have been measured by X-ray diffraction, grazing incidence X-ray specular and off-specular reflectivities, and transmission electron microscopy (TEM). The surface of the Si∕Ge superlattice is smooth, and there are no Ge–Si huts appearing on the surface. The roughness of the surfaces is less than 3 Å. Large lattice strain induced by lattice mismatch between Si and Ge is found to be relaxed because of the intermixing of Ge and Si at the Si∕Ge interface.

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High mobility AlGaN/GaN heterostructures grown on Si substrates using a large lattice-mismatch induced stress control technology

Applied Physics Letters ◽

10.1063/1.4917504 ◽

2015 ◽

Vol 106 (14) ◽

pp. 142106 ◽

Cited By ~ 22

Author(s):

Jianpeng Cheng ◽

Xuelin Yang ◽

Ling Sang ◽

Lei Guo ◽

Anqi Hu ◽

...

Keyword(s):

Lattice Mismatch ◽

High Mobility ◽

Control Technology ◽

Stress Control ◽

Si Substrates ◽

Induced Stress ◽

Large Lattice ◽

Large Lattice Mismatch

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Epitaxial Growth of Copper, Silver and Gold on a Semiconducting Layered Material: Tungsten Disulfide

MRS Proceedings ◽

10.1557/proc-102-41 ◽

1987 ◽

Vol 102 ◽

Cited By ~ 2

Author(s):

D. L. Doering ◽

F. S. Ohuchi ◽

W. Jaegermann ◽

B. A. Parkinson

Keyword(s):

Thin Films ◽

Epitaxial Growth ◽

Lattice Mismatch ◽

Layered Material ◽

Tungsten Disulfide ◽

Layer By Layer ◽

Metal Contacts ◽

Layered Semiconductor ◽

Large Lattice ◽

Large Lattice Mismatch

ABSTRACTThe growth of copper, silver and gold thin films on tungsten disulfide has been examined as a model of metal contacts on a layered semiconductor. All three metals were found to grow epitaxially on the WS2. However, Cu appears to form a discontinuous film while Au and Ag grow layer by layer. Such epitaxial growth is somewhat surprising since there is a large lattice mismatch between the metals and the WS2.

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