Nano-Structured TiN/TiBN Multilayer Thin Films

Nano-structured TiN/TiBN multilayer thin films were deposited onto unheated Si(100) substrates by reactive unbalanced dc-magnetron sputtering in an Ar-N2 gas mixture at a pulsed-bias voltage of –60 V. The effects of the bilayer thickness (Λ = 1.8-7.7 nm) on microstructures and mechanical properties have been analyzed using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and microindentation measurements. Microstructure studies revealed that the TiN layers were fcc B1-NaCl structure comprising of (111)- and (200)-oriented grains depending on Λ, while the TiBN layers were amorphous. Significant relationships were found between hardness (H) and Λ. A maximum hardness of ~30 GPa was observed in a multilayer film with = 1.8 nm. The possible hardness enhancement mechanism was also discussed.

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The Ti-B-N System: Nanocomposite nc-TiN/a-(TiB2, BN) and Nano-Multilayer nc-TiN/a-TiBN Thin Films

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2008.18301 ◽

2008 ◽

Vol 8 (5) ◽

pp. 2713-2718

Author(s):

Y. H. Lu ◽

K. Chu ◽

Y. G. Shen

Keyword(s):

Thin Films ◽

Dislocation Motion ◽

Structural Barriers ◽

Mechanical Behaviors ◽

Bilayer Thickness ◽

Maximum Hardness ◽

X Ray Diffraction ◽

X Ray ◽

Grain Sizes ◽

Transmission Electron

The nanostructures and mechanical properties of nanocomposite nc-TiN/a-(TiB2, BN) and nanostructured multilayers nc-TiN/a-TiBN were investigated using X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), microindentation, and stress measurements. It was found that the monolayer Ti-B-N thin films consisted of nanometer-sized crystalline (nc-) Ti(N, B) embedded into amorphous (a-) (TiB2, BN) matrix. When B content was below ∼16 at.%, two different-sized nanocrystallites with mean grain sizes of ∼3 and 9 nm respectively were embedded in a-TiB2. With increasing B incorporation (>∼27 at.%), more uniform nanograins was embedded a-(TiB2, BN). Incorporation of B not only decreased the size of nanocrystallites, but also gave rise to twinning deformation in nanocrystallites. A maximum hardness of ∼44 GPa was achieved at B content of 19 at.%. It was also found that the nanostructure and mechanical behaviors of nc-TiN/a-TiBN multilayers was dependent on the modulation length (bilayer thickness Λ). Decrease of Λ made the preferred orientation of nc-TiN gradually transform from (200) to (111). A maximum hardness of ∼30 GPa was achieved at Λ = 1.8 nm. Deflection from this Λ value decreased hardness. By contrast, the residual compressive stress value monotonically increased with decrease of Λ. The enhancement of the hardness was due to the coherent stresses and the structural barriers to dislocation motion in the interface.

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Microstructure Characterization of Si/C Multilayer Thin Films

Materials Science Forum ◽

10.4028/www.scientific.net/msf.743-744.910 ◽

2013 ◽

Vol 743-744 ◽

pp. 910-914

Author(s):

Ting Han ◽

Geng Rong Chang ◽

Yun Jin Sun ◽

Fei Ma ◽

Ke Wei Xu

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Multilayer Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Post Annealing ◽

Transmission Electron ◽

Twin Defects ◽

Modulation Ratio

Si/C multilayer thin films were prepared by magnetron sputtering and post-annealing in N2 atmosphere at 1100 for 1h. X-ray diffraction (XRD), Raman scattering and high-resolution transmission electron microscopy (HRTEM) were applied to study the microstructures of the thin films. For the case of Si/C modulation ratio smaller than 1,interlayer diffusion is evident, which promotes the formation of α-SiC during thermal annealing. If the modulation ratio is larger than 1, the Si sublayers are partially crystallized, and the thicker the Si sublayers are, the crystallinity increases. To be excited, brick-shaped nc-Si is directly observed by HRTEM. The brick-shaped nc-Si appears to be more regular near the Si (100) substrate but with twin defects. The results are instructive in the application of solar cells.

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Correlation of stress state and nanohardness via heat treatment of nickel-aluminide multilayer thin films

Journal of Materials Research ◽

10.1557/jmr.2004.0435 ◽

2004 ◽

Vol 19 (11) ◽

pp. 3374-3381 ◽

Cited By ~ 5

Author(s):

Evan A. Sperling ◽

Peter M. Anderson ◽

Jennifer L. Hay

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Stress State ◽

Internal Stress ◽

Biaxial Stress ◽

Multilayer Thin Films ◽

Bilayer Thickness ◽

X Ray Diffraction ◽

X Ray ◽

Biaxial Stress State

Heat treatment of γ-Ni(Al)/γ′-Ni3Al multilayer thin films demonstrates that multilayer hardness correlates with the magnitude of biaxial stress in alternating layers. Films with a columnar grain morphology and (001) texture were fabricated over a range of volume fraction and bilayer thickness via direct current magnetron sputtering onto NaCl (001) substrates at 623 K. The films were removed from substrates, heat-treated at either 673 K or 1073 K in argon, and then mounted for nanoindentation and x-ray diffraction. The biaxial stress state in each phase was furnished from x-ray diffraction measurement of (002) interplanar spacings. The 673 K treatment increases the magnitude of alternating biaxial stress state by 70 to 100% and increases hardness by 25 to 100%, depending on bilayer thickness. In contrast, the 1073 K heat treatment decreases the stress magnitude by 70% and decreases hardness by 50%. The results suggest that the yield strength of these thin films is controlled, in part, by the magnitude of internal stress. Further, thermal treatments are demonstrated to be an effective means to manipulate internal stress.

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Texture in Ti/Al and Nb/Al multilayer thin films: Role of Cu

Journal of Materials Research ◽

10.1557/jmr.2001.0202 ◽

2001 ◽

Vol 16 (5) ◽

pp. 1449-1459 ◽

Cited By ~ 6

Author(s):

G. Lucadamo ◽

K. Barmak ◽

K. P. Rodbell

Keyword(s):

Thin Films ◽

Film Growth ◽

Fiber Texture ◽

Fiber Axis ◽

Multilayer Thin Films ◽

Bilayer Thickness ◽

X Ray ◽

Transmission Electron ◽

Pole Figures

Fiber texture in Ti/Al and Nb/Al polycrystalline multilayer thin films, with bilayer thicknesses (Λ) ranging from 20–333 nm and having a fixed stoichiometry of 1/3, has been investigated by using x-ray pole figures and transmission electron microscopy. Two sets of films were deposited; one set contained pure Al and the other Al–1.0 wt% Cu. The results indicated that texture was strengthened by the formation of a coherent superlattice for the Nb/pure-Al film with the smallest bilayer thickness. By contrast, the texture in Ti/pure-Al films with a similar period was not as strong. The texture also decreased with increasing Λ for both the Ti/pure-Al and Nb/pure-Al films. An increase in the width of the Al (111) peak and an offset of the fiber axis from the substrate normal of 5–8° was observed in the Λ = 333 nm films prepared by using Al–1.0 wt% Cu. The decrease in texture on addition of Cu to Al was attributed primarily to an increase in interlayer roughness as a consequence of reduction in the Al(Cu) grain size. These observations were interpreted in the context of structure zone and dynamic roughness models of film growth.

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TEM studies of solid-state reactions in sputter-deposited Nb/Al multilayer thin films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167561 ◽

1996 ◽

Vol 54 ◽

pp. 1020-1021

Author(s):

F. Ma ◽

S. Vivekanand ◽

K. Barmak ◽

C. Michaelsen

Keyword(s):

Thin Films ◽

Solid State ◽

Stoichiometric Composition ◽

Analytical Electron Microscopy ◽

Grain Structure ◽

Solid State Reactions ◽

Multilayer Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Sputter Deposited

Solid state reactions in sputter-deposited Nb/Al multilayer thin films have been studied by transmission and analytical electron microscopy (TEM/AEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The Nb/Al multilayer thin films for TEM studies were sputter-deposited on (1102)sapphire substrates. The periodicity of the films is in the range 10-500 nm. The overall composition of the films are 1/3, 2/1, and 3/1 Nb/Al, corresponding to the stoichiometric composition of the three intermetallic phases in this system.Figure 1 is a TEM micrograph of an as-deposited film with periodicity A = dA1 + dNb = 72 nm, where d's are layer thicknesses. The polycrystalline nature of the Al and Nb layers with their columnar grain structure is evident in the figure. Both Nb and Al layers exhibit crystallographic texture, with the electron diffraction pattern for this film showing stronger diffraction spots in the direction normal to the multilayer. The X-ray diffraction patterns of all films are dominated by the Al(l 11) and Nb(l 10) peaks and show a merging of these two peaks with decreasing periodicity.

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Palladium Nanowire Thin Films via Template Growth

MRS Proceedings ◽

10.1557/proc-775-p4.7 ◽

2003 ◽

Vol 775 ◽

Author(s):

Donghai Wang ◽

David T. Johnson ◽

Byron F. McCaughey ◽

J. Eric Hampsey ◽

Jibao He ◽

...

Keyword(s):

Thin Film ◽

Electron Microscopy ◽

Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Conductive Substrate ◽

Palladium Nanowires ◽

Efficient Route ◽

Silica Thin Film

AbstractPalladium nanowires have been electrodeposited into mesoporous silica thin film templates. Palladium continually grows and fills silica mesopores starting from a bottom conductive substrate, providing a ready and efficient route to fabricate a macroscopic palladium nanowire thin films for potentially use in fuel cells, electrodes, sensors, and other applications. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate it is possible to create different nanowire morphology such as bundles and swirling mesostructure based on the template pore structure.

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Transparent Conductive Cu-In-O Thin Films Deposited by Reactive DC Magnetron Sputtering with Different Targets

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.2752 ◽

2011 ◽

Vol 239-242 ◽

pp. 2752-2755

Author(s):

Fan Ye ◽

Xing Min Cai ◽

Fu Ping Dai ◽

Dong Ping Zhang ◽

Ping Fan ◽

...

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Optical Band Gap ◽

Diffraction Peak ◽

X Ray Diffraction ◽

Dc Magnetron Sputtering ◽

Flow Rates ◽

X Ray ◽

Equal Distance ◽

Transmittance Curve

Transparent conductive Cu-In-O thin films were deposited by reactive DC magnetron sputtering. Two types of targets were used. The first was In target covered with a fan-shaped Cu plate of the same radius and the second was Cu target on which six In grains of 1.5mm was placed with equal distance between each other. The samples were characterized with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV/VIS spectrophotometer, four-probe measurement etc. SEM shows that the surfaces of all the samples are very smooth. EDX shows that the samples contain Cu, In as well as O, and different targets result in different atomic ratios of Cu to In. A diffraction peak related to rhombohedra-centered In2O3(012) is observed in the XRD spectra of all the samples. For both the two targets, the transmittance decreases with the increase of O2flow rates. The direct optical band gap of all the samples is also estimated according to the transmittance curve. For both the two targets, different O2flow rates result in different sheet resistances and conductivities. The target of Cu on In shows more controllability in the composition and properties of Cu-In-O films.

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Limitations to the use of Sb as a Surfactant During SiGe MBE

MRS Proceedings ◽

10.1557/proc-533-289 ◽

1998 ◽

Vol 533 ◽

Author(s):

Glenn G. Jernigan ◽

Conrad L. Silvestre ◽

Mohammad Fatemi ◽

Mark E. Twigg ◽

Phillip E. Thompson

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Quantum Well ◽

Photoelectron Spectroscopy ◽

Surface Coverage ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Alloy Concentration

AbstractThe use of Sb as a surfactant in suppressing Ge segregation during SiGe alloy growth was investigated as a function of Sb surface coverage, Ge alloy concentration, and alloy thickness using xray photoelectron spectroscopy, x-ray diffraction, and transmission electron microscopy. Unlike previous studies where Sb was found to completely quench Ge segregation into a Si capping layer, we find that Sb can not completely prevent Ge segregation while Si and Ge are being co-deposited. This results in the production of a non-square quantum well with missing Ge at the beginning and extra Ge at the end of the alloy. We also found that Sb does not relieve strain in thin films but does result in compositional or strain variations within thick alloy layers.

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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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