Indentation-Induced Mechanical Deformation Behaviors of AlN Thin Films Deposited onc-Plane Sapphire

The mechanical properties and deformation behaviors of AlN thin films deposited onc-plane sapphire substrates by helicon sputtering method were determined using the Berkovich nanoindentation and cross-sectional transmission electron microscopy (XTEM). The load-displacement curves show the “pop-ins” phenomena during nanoindentation loading, indicative of the formation of slip bands caused by the propagation of dislocations. No evidence of nanoindentation-induced phase transformation or cracking patterns was observed up to the maximum load of 80 mN, from either XTEM or atomic force microscopy (AFM) of the mechanically deformed regions. Instead, XTEM revealed that the primary deformation mechanism in AlN thin films is via propagation of dislocations on both basal and pyramidal planes. Furthermore, the hardness and Young’s modulus of AlN thin films estimated using the continuous contact stiffness measurements (CSMs) mode provided with the nanoindenter are 16.2 GPa and 243.5 GPa, respectively.

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WO3:Mo and WO3:Ti Thin Films Deposited by Spray Pyrolysis: The Influence of Metallic Concentration on Physical Properties: An Electron Microscopy and Atomic Force Study

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.286.49 ◽

2019 ◽

Vol 286 ◽

pp. 49-63

Author(s):

Dwight Acosta ◽

Francisco Hernández ◽

Alejandra López-Suárez ◽

Carlos Magaña

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Ultra Violet ◽

Surface Characteristics ◽

Structural Defects ◽

Force Microscopy ◽

Glass Substrates ◽

Atomic Force ◽

Transmission Electron ◽

Resolution Electron

WO3:Mo and WO3:Ti thin films have been deposited on FTO/Glass substrates by the pulsed chemical spray technique at a substrate temperature of Ts= 450°C. The influence of Mo and Ti doping on the structural, electrical, and optical behavior of WO3thin films, has been studied by X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), Ultra Violet and Visible Spectrometry (UV-VIS), and Surface Conductivity Methods (Four Points). Doped WO3films presents similar polycrystalline structures but with noticeable modifications in surface configurations at micrometric and nanometric levels, as the Mo and Ti concentration is systematically increased in the starting sprayed solution. From processed High-Resolution Electron Micrographs (HREM), a low density of structural defects was found on pure and doped WO3grains. This lead to conclude that variations in films surface characteristics are mainly related with metallic doping concentrations which in turn, have noticeable influence in electrical and optical behaviors reported in this work.

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Epitaxial BaTiO3 Thin Films on Different Substrates for Optical Waveguide Applications

MRS Proceedings ◽

10.1557/proc-597-145 ◽

1999 ◽

Vol 597 ◽

Cited By ~ 5

Author(s):

M. Siegert ◽

Judit G. Lisoni ◽

C. H. Lei ◽

A. Eckau ◽

W. Zander ◽

...

Keyword(s):

Thin Films ◽

Optical Waveguides ◽

Rutherford Backscattering Spectrometry ◽

Optical Data ◽

X Ray Diffraction ◽

X Ray ◽

Force Microscopy ◽

Ion Channeling ◽

Atomic Force ◽

Transmission Electron

AbstractIn the process of developing thin film electro-optical waveguides we investigated the influence of different substrates on the optical and structural properties of epitaxial BaTiO3 thin films. These films are grown by on-axis pulsed laser deposition (PLD) on MgO(100), MgAl2O4(100), SrTiO3(100) and MgO buffered A12O3(1102) substrates. The waveguide losses and the refractive indices were measured with a prism coupling setup. The optical data are correlated to the results of Rutherford backscattering spectrometry/ion channeling (RBS/C). X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM). BaTiO3 films on MgO(100) substrates show planar waveguide losses of 3 dB/cm and ridge waveguide losses of 5 dB/cm at a wavelength of 633 nm.

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Structural and Ferroelectric Properties of Epitaxial PbZr0.52Ti0.48O3 and BaTiO3 Thin Films Prepared on SrRuO3/SrTiO3(100) Substrates

MRS Proceedings ◽

10.1557/proc-688-c8.10.1 ◽

2001 ◽

Vol 688 ◽

Cited By ~ 3

Author(s):

J. Rodríguez Contreras ◽

J. Schubert ◽

U. Poppe ◽

O. Trithaveesak ◽

K. Szot ◽

...

Keyword(s):

Thin Films ◽

Rutherford Backscattering Spectrometry ◽

Ferroelectric Properties ◽

Hysteresis Loops ◽

Tunnel Current ◽

Single Crystalline ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Ferroelectric Hysteresis

AbstractWe have prepared single crystalline epitaxial PbZr0.52Ti0.48O3 (PZT) and BaTiO3 (BTO) thin films on single crystalline epitaxial SrRuO3 (SRO) thin films grown on SrTiO3 (100) (STO) substrates. PZT and SRO thin films were grown using high-pressure on-axis sputtering and BTO using pulsed laser deposition (PLD). The film thickness ranged between 12 to 165 nm. Their excellent structural properties, surface smoothness and interface sharpness were demonstrated by X-Ray Diffraction measurements (XRD), High Resolution Transmission Electron Microscopy (HRTEM) and Atomic Force Microscopy (AFM). Rutherford Backscattering Spectrometry and Channeling measurements (RBS/C) were used to analyze stoichiometry and crystalline quality. Ferroelectric hysteresis loops were obtained for all films of a thickness down to 12 nm showing a decrease in the remanent polarization Pr and an increase in the coercive field Ec towards thinner film thicknesses. Furthermore we have prepared tunneling junctions with a PZT or BTO barrier thickness of 3-6 nm. Reproducible bi-stable I-V-curves and bias dependence of the conductance were obtained suggesting an influence of the ferroelectric properties of the barrier material on the tunnel current.

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Cross-Sectional Nanoindentation of Alumina Thin Films Deposited by Pulsed Laser Deposition Process

Materials, Nondestructive Evaluation, and Pressure Vessels and Piping ◽

10.1115/imece2006-14924 ◽

2006 ◽

Author(s):

Sudheer Neralla ◽

Sergey Yarmolenko ◽

Dhananjay Kumar ◽

Devdas Pai ◽

Jag Sankar

Keyword(s):

Thin Films ◽

Pulsed Laser Deposition ◽

Pulsed Laser ◽

High Hardness ◽

Deposition Process ◽

Laser Deposition ◽

Cross Sectional ◽

Adhesion Properties ◽

Force Microscopy ◽

Atomic Force

Alumina is a widely used ceramic material due to its high hardness, wear resistance and dielectric properties. The study of phase transformation and its correlation to the mechanical properties of alumina is essential. In this study, interfacial adhesion properties of alumina thin films are studied using cross-sectional nanoindentation (CSN) technique. Alumina thin films are deposited at 200 and 700 °C, on Si (100) substrates with a weak Silica interface, using pulsed laser deposition (PLD) process. Effect of annealing on the surface morphology of the thin films is studied using atomic force microscopy. Xray diffraction studies revealed that alumina thin films are amorphous in nature at 200 °C and polycrystalline with predominant gamma alumina phase at 700 °C.

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TEM Studies on the Microstructure of m-Face Grown 4H-SiC by Solution Growth

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1004.414 ◽

2020 ◽

Vol 1004 ◽

pp. 414-420

Author(s):

Junro Takahashi ◽

Kotaro Kawaguchi ◽

Kazuhiko Kusunoki ◽

Tomoyuki Ueyama ◽

Kazuhito Kamei

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Solution Growth ◽

Spiral Growth ◽

Growth Surface ◽

Vicinal Surface ◽

Cross Sectional ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron

We have studied the microstructure of the growth surface of the 4H-SiC grown by the m-face solution growth. Atomic Force Microscopy (AFM) revealed the micro-striped morphology with the asperity of several nm in the band-like morphology region. The cross-sectional Transmission Electron Microscopy (XTEM) showed that the growth surface consisted of a bunch of nanofacets and vicinal surface. This peculiar morphology is totally different from that of conventional spiral growth on c-face, which can be closely related with the growth mechanism of the m-face solution growth.

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Anisotropic Behaviour of Surface Roughening in Lattice Mismatched Heteroepitaxial Thin Films

MRS Proceedings ◽

10.1557/proc-436-487 ◽

1996 ◽

Vol 436 ◽

Cited By ~ 7

Author(s):

Cengiz S. Ozkan ◽

William D. Nix ◽

Huajian Gao

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Lattice Mismatch ◽

Surface Roughening ◽

Silicon Substrates ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Annealing Experiments

AbstractHeteroepitaxial Si1-xGex. thin films deposited on silicon substrates exhibit surface roughening via surface diffusion under the effect of a compressive stress which is caused by a lattice mismatch. In these films, surface roughening can take place in the form of ridges which can be aligned along <100> or <110> directions, depending on the film thickness. In this paper, we investigate this anisotropic dependence of surface roughening and present an analysis of it. We have studied the surface roughening behaviour of 18% Ge and 22% Ge thin films subjected to controlled annealing experiments. Transmission electron microscopy and atomic force microscopy have been used to study the morphology and microstructure of the surface ridges and the dislocations that form during annealing.

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Nanomechanical Properties and Nanostructure of CMG and CMP Machined Si Substrates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.381-382.525 ◽

2008 ◽

Vol 381-382 ◽

pp. 525-528 ◽

Cited By ~ 2

Author(s):

B.L. Wang ◽

Han Huang ◽

Jin Zou ◽

Li Bo Zhou

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Substrate Surface ◽

Transmission Electron Microscopy Analysis ◽

Cross Sectional ◽

Force Microscopy ◽

Si Substrates ◽

Atomic Force ◽

Transmission Electron ◽

Electron Microscopy Analysis

Silicon (100) substrates machined by chemo-mechanical-grinding (CMG) and chemicalmechanical- polishing (CMP) were investigated using atomic force microscopy, cross-sectional transmission electron microscopy and nanoindentation. It was found that the substrate surface after CMG was slightly better than machined by CMP in terms of roughness. The transmission electron microscopy analysis showed that the CMG-generated subsurface was defect-free, but the CMP specimen had a crystalline layer of about 4 nm in thickness on the top of the silicon lattice as evidenced by the extra diffraction spots. Nanoindentation results indicated that there exists a slight difference in mechanical properties between the CMG and CMP machined substrates.

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Self-Assembled Growth of Highly Oriented Para- Sexiphenyl Thin Films Controlled by Elastic Strain

MRS Proceedings ◽

10.1557/proc-665-c5.24 ◽

2001 ◽

Vol 665 ◽

Cited By ~ 1

Author(s):

Andrei Yu. Andreev ◽

Helmut Sitter ◽

Christoph J. Brabec ◽

Peter Hinterdorfer ◽

Günter Springholz ◽

...

Keyword(s):

Thin Films ◽

Substrate Surface ◽

Growth Time ◽

Crystallographic Structure ◽

Force Microscopy ◽

Atomic Force ◽

Transmission Electron ◽

Degree Of Anisotropy ◽

Figure Technique ◽

Crystallographic Planes

ABSTRACTWe have studied the structure and growth regularities of highly ordered para-sexiphenyl (C36H26) thin films deposited by Hot Wall Epitaxy on mica. In particular, atomic force microscopy (AFM) was used to investigate the early growth stage of these films, in order to find the process controlling parameters. It was shown that the substrate temperature and the growth time are important parameters for control of the film morphology, in terms of the degree of anisotropy and long range order. X-ray diffraction pole figure technique and transmission electron microscopy were also used to characterize the crystallographic structure of the thicker films. We have shown that the highly ordered crystallites of para-sexiphenyl (showing needle-like morphology by AFM) are oriented with their (11 1 ) or (11 2 ) crystallographic planes parallel to the substrate surface. For each of these two orientations there are two opposite directions for growth of crystallites reflecting the two-fold symmetry of the mica surface.

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PLD Grown 3C-SiC Thin Films on Si: Morphology and Structure

Materials Science Forum ◽

10.4028/www.scientific.net/msf.821-823.213 ◽

2015 ◽

Vol 821-823 ◽

pp. 213-216

Author(s):

S.M. Ryndya ◽

N.I. Kargin ◽

A.S. Gusev ◽

E.P. Pavlova

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Rutherford Backscattering Spectrometry ◽

X Ray Diffraction ◽

Force Microscopy ◽

Selected Area Electron Diffraction ◽

Atomic Force ◽

Transmission Electron ◽

Influence Of Substrate ◽

Composition Structure

Silicon carbide thin films were obtained on Si (100) and (111) substrates by means of vacuum laser ablation of α-SiC ceramic target. The influence of substrate temperature on composition, structure and surface morphology of experimental samples was examined using Rutherford backscattering spectrometry (RBS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), conventional and high-resolution transmission electron microscopy (TEM/HRTEM), atomic force microscopy (AFM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) methods.

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Growth of heteroepitaxial GaSb thin films on Si(100) substrates

Journal of Materials Research ◽

10.1557/jmr.2004.0307 ◽

2004 ◽

Vol 19 (8) ◽

pp. 2315-2321 ◽

Cited By ~ 4

Author(s):

Thang Nguyen ◽

Walter Varhue ◽

Edward Adams ◽

Mark Lavoie ◽

Stephen Mongeon

Keyword(s):

Thin Films ◽

Film Thickness ◽

Lattice Mismatch ◽

Stacking Faults ◽

Heteroepitaxial Growth ◽

X Ray Diffraction ◽

Force Microscopy ◽

Radio Frequency Sputtering ◽

Atomic Force ◽

Transmission Electron

The heteroepitaxial growth of GaSb thin films on Si(100) and GaAs(100) substrates is presented. The growth technique involves the use of atomic Ga and Sb species, which are provided by thermal effusion and radio frequency sputtering, respectively. The crystalline quality of the heteroepitaxial GaSb film on the Si substrate is high despite the larger lattice mismatch. Epitaxial quality is determined by high-resolution x-ray diffraction and Rutherford backscatter spectrometry channeling. Atomic-force microscopy is used to monitor the evolution of surface morphology with increasing film thickness. Transmission electron microscopy shows the formation of stacking faults at the Si/GaSb interface and their eventual annihilation with increasing GaSb film thickness. Annihilation of stacking faults occurs when two next-neighbor mounds meet during the overgrowth of a common adjacent mound.

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