High Resolution EFTEM and PEELS of Ga/GaAs Nano–“Ice Cream Cones” Grown by Dual-Wavelength Pulsed Laser Deposition

ABSTRACTEpitaxial growth of TiN films on GaAs(100) by pulsed laser deposition has been studied. Excimer KrF laser (λ=248 nm, τ=30 ns) has been used for deposition of TiN films in a chamber maintained at vacuum of ≤ 10−6 torr. The microstructure of TiN films has been characterized by x-ray diffraction and transmission electron microscopy (TEM). Cross-sectional high resolution TEM showed a smooth unreacted interface between the single crystalline TiN film and GaAs. The predominant epitaxial relationship was found to be [110]TiN//[010]GaAs, (220)TiN//(040)GaAs at a substrate temperature of 350°C. Modelling of epitaxial growth showed that the interfacial energy is an important term responsible for 45° rotation of the TiN unit cell with respect to that of GaAs. The high strain energy associated with the coherent epilayer is reduced by domain epitaxial growth. These films were characterized using high-resolution TEM techniques, and experimental results were rationalized by thin film growth modeling.

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Calibration of an off-axis quartz crystal thickness monitor for a pulsed laser deposition system using a high resolution scanning electron microscope

Thin Solid Films ◽

10.1016/0040-6090(93)90656-a ◽

1993 ◽

Vol 236 (1-2) ◽

pp. 125-129 ◽

Cited By ~ 2

Author(s):

S.D. Walck ◽

J.S. Zabinski ◽

M.S. Donley ◽

J.E. Bultman

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Scanning Electron Microscope ◽

Pulsed Laser Deposition ◽

Quartz Crystal ◽

Pulsed Laser ◽

Laser Deposition ◽

Crystal Thickness ◽

Scanning Electron

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Structure Quality of LuFeO3 Epitaxial Layers Grown by Pulsed-Laser Deposition on Sapphire/Pt

Materials ◽

10.3390/ma13010061 ◽

2019 ◽

Vol 13 (1) ◽

pp. 61 ◽

Cited By ~ 2

Author(s):

Sondes Bauer ◽

Adriana Rodrigues ◽

Lukáš Horák ◽

Xiaowei Jin ◽

Reinhard Schneider ◽

...

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Lattice Parameter ◽

Laser Deposition ◽

X Ray Diffraction ◽

X Ray

Structural quality of LuFeO 3 epitaxial layers grown by pulsed-laser deposition on sapphire substrates with and without platinum Pt interlayers has been investigated by in situ high-resolution X-ray diffraction (reciprocal-space mapping). The parameters of the structure such as size and misorientation of mosaic blocks have been determined as functions of the thickness of LuFeO 3 during growth and for different thicknesses of platinum interlayers up to 40 nm. By means of fitting of the time-resolved X-ray reflectivity curves and by in situ X-ray diffraction measurement, we demonstrate that the LuFeO 3 growth rate as well as the out-of-plane lattice parameter are almost independent from Pt interlayer thickness, while the in-plane LuFeO 3 lattice parameter decreases. We reveal that, despite the different morphologies of the Pt interlayers with different thickness, LuFeO 3 was growing as a continuous mosaic layer and the misorientation of the mosaic blocks decreases with increasing Pt thickness. The X-ray diffraction results combined with ex situ scanning electron microscopy and high-resolution transmission electron microscopy demonstrate that the Pt interlayer significantly improves the structure of LuFeO 3 by reducing the misfit of the LuFeO 3 lattice with respect to the material underneath.

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Synthesis of Single Crystal Gallium Nitride Films on Sapphire by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-526-293 ◽

1998 ◽

Vol 526 ◽

Author(s):

A.K. Sharma ◽

S. Oktyabrsky ◽

K. Dovidenko ◽

J. Narayan

Keyword(s):

Gallium Nitride ◽

High Resolution ◽

Substrate Temperature ◽

Single Crystal ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Film Surface ◽

Laser Deposition ◽

Extended Defects ◽

Wurtzite Phase

AbstractPulsed laser deposition has been explored to synthesize gallium nitride films on c-plane sapphire by ablating a pressed GaN target in vacuum. The films were characterized by X-ray diffraction, and high resolution transmission electron microscopy to study the nature of epitaxy, growth, and defect content. Single crystal films with narrow o0-rocking curve width were deposited in the substrate temperature range 700-780°C. High resolution microscopy revealed uniform film surface at lower substrate temperature for films as thin as 150 nm. The predominant extended defects were found to be threading edge dislocations (Burgers vector 1/3<1120>) with the density ~1010 cm-2. The thickness of all these films were in the range 100-150 nm. The coexistence of zincblende phase of GaN alongwith wurtzite phase was found in the film deposited at 780°C. The stabilization of metastable zincblende phase at higher temperature point towards the noneqilibrium nature of laser ablation. These preliminary results indicate the potential of PLD to synthesize high quality GaN films free of hydrogen.

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A Simple and Effective Route to Annihilate Defects in Nanocrystalline SnO2 Thin Films Prepared by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-1026-c17-03 ◽

2007 ◽

Vol 1026 ◽

Author(s):

Zhiwen Chen ◽

C. M. L. Wu ◽

C. H. Shek ◽

J. K. L. Lai ◽

Z. Jiao ◽

...

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Pulsed Laser Deposition ◽

Gas Sensors ◽

Pulsed Laser ◽

Laser Deposition ◽

Transmission Electron ◽

Sno2 Thin Films

AbstractThe microstructural defects of nanocrystalline SnO2 thin films prepared by pulsed laser deposition have been investigated using transmission electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy. Defects inside nanocrystalline SnO2 thin films could be significantly reduced by annealing the SnO2 thin films at 300 °C for 2 h. High-resolution transmission electron microscopy showed that stacking faults and twins were annihilated upon annealing. In particular, the edges of the SnO2 nanoparticles demonstrated perfect lattices free of defects after annealing. Raman spectra also confirmed that annealing the specimen was almost defect-free. By using thermal annealing, defect-free nanocrystalline SnO2 thin films can be prepared in a simple and practical way, which holds promise for applications as transparent electrodes and solid-state gas sensors.

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Interpretation of the two-components observed in high resolution X-ray diffraction ω scan peaks for mosaic ZnO thin films grown on c-sapphire substrates using pulsed laser deposition

Thin Solid Films ◽

10.1016/j.tsf.2011.04.036 ◽

2011 ◽

Vol 519 (19) ◽

pp. 6369-6373 ◽

Cited By ~ 16

Author(s):

O. Durand ◽

A. Letoublon ◽

D.J. Rogers ◽

F. Hosseini Teherani

Keyword(s):

Thin Films ◽

High Resolution ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Laser Deposition ◽

Zno Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Sapphire Substrates

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Microstructural study of growth of a YBa2Cu3O7−x/LaAlO3/YBa2Cu3O7−x trilayered film by pulsed laser deposition

Journal of Materials Research ◽

10.1557/jmr.1996.0378 ◽

1996 ◽

Vol 11 (12) ◽

pp. 2971-2975 ◽

Cited By ~ 5

Author(s):

Y. H. Li ◽

A. Staton-Bevan ◽

J. A. Kilner ◽

Z. Trajanovic ◽

T. Venkatesan

Keyword(s):

High Resolution ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Stacking Fault ◽

Laser Deposition ◽

Second Phase ◽

Ybco Layer ◽

Transmission Electron ◽

Nominal Thickness ◽

High Resolution Images

The growth process of a YBCO/LaAlO3/YBCO trilayered film made by pulsed laser deposition has been studied by high resolution transmission electron microscopy (HRTEM). The high resolution images of the cross-section samples have shown that a 7 nm layer of LaAlO3 has been grown epitaxially between c-axis oriented YBCO layers having the nominal thickness of 250 nm. A stacking fault in the LaAlO3 layer may introduce a stacking fault into the YBCO layer, which may form nucleation sites for α-axis oriented grains. A second phase had been formed at the interface between the LaAlO3 layer and the lower YBCO layer, which has been identified by image simulation and energy dispersive x-ray (EDX) analysis as a new tetragonal La–Al–Cu–O phase based on LaAlO3 in which some of Al atoms have been replaced by Cu. The approximate lattice parameters of the new phase are a = 0.38 nm and c = 0.76 nm. However, no second phase was found at the interface between the lower YBCO layer and the LaAlO3 substrate.

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Microanalysis of silicate glass films grown on α-Al2O3 by pulsed-laser deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148022 ◽

1993 ◽

Vol 51 ◽

pp. 438-439

Author(s):

Michael P. Mallamaci ◽

James Bentley ◽

C. Barry Carter

Keyword(s):

Liquid Phase ◽

Single Crystal ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

Ceramic Materials ◽

Laser Deposition ◽

Triple Junctions ◽

Ion Milling ◽

Multicomponent Oxides ◽

Glass Films

Glass-oxide interfaces play important roles in developing the properties of liquid-phase sintered ceramics and glass-ceramic materials. Deposition of glasses in thin-film form on oxide substrates is a potential way to determine the properties of such interfaces directly. Pulsed-laser deposition (PLD) has been successful in growing stoichiometric thin films of multicomponent oxides. Since traditional glasses are multicomponent oxides, there is the potential for PLD to provide a unique method for growing amorphous coatings on ceramics with precise control of the glass composition. Deposition of an anorthite-based (CaAl2Si2O8) glass on single-crystal α-Al2O3 was chosen as a model system to explore the feasibility of PLD for growing glass layers, since anorthite-based glass films are commonly found in the grain boundaries and triple junctions of liquid-phase sintered α-Al2O3 ceramics.Single-crystal (0001) α-Al2O3 substrates in pre-thinned form were used for film depositions. Prethinned substrates were prepared by polishing the side intended for deposition, then dimpling and polishing the opposite side, and finally ion-milling to perforation.

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