Microstructural Evolution Of Ti/Ni AND Ni/Ti Bilayer Thin Films

1991 ◽  
Vol 238 ◽  
Author(s):  
E. Haftek ◽  
M. Tan ◽  
A. Waknis ◽  
J. A. Barnard
Keyword(s):  
Thin Films ◽  
Microstructural Evolution ◽  
Single Layer ◽  
Film Plane ◽  
Structural Defects ◽  
Intergranular Cracking ◽  
Compound Formation ◽  
Transmission Electron ◽  
Intermetallic Compound Formation ◽  
Carbon Coated

ABSTRACTThe growth and microstructural evolution of sputtered Ti/Ni and Ni/Ti bilayer thin films have been investigated as a function of Ti and Ni layer thicknesses in as-deposited and annealed states (280°C for 60 minutes) by transmission electron microscopy (TEM). The Ti layer thickness was varied systematically from 4.9 to 29.4 nm while the Ni thickness was varied from 3.2 to 19.2 nm. Carbon coated Cu TEM grids were used as substrates. Microstructural characteristics of the bilayers were found to be deposition sequence dependent. Ti/Ni bilayers exhibit a finer microstructure than N/T especially for the thicker films. Intergranular cracking is observed in the Ti/Ni sequence. In both deposition sequences the presence of Ni promotes the crystallization of Ti in the as-deposited state. By contrast, single layer Ti films deposited under the same sputtering conditions remain amorphous up to 9.8 nm thick. The Ti{002} electron diffraction ring is present in all of the bilayers even those with the thinnest Ti layers. Additional Ti rings, {010} and {011}, develop in bilayers with thicker Ti layers. In both bilayer systems a tensile stress parallel to the film plane is present in the Ni layer. Annealing removes structural defects and relieves the stress. A large increase in Ni{111} spacing can be attributed to dissolution of Ti atoms into the Ni lattice. Annealing also produces evidence of grain growth, intermetallic compound formation, and amorphization in both Ti/Ni and Ni/Ti samples.

Microstructural Evolution of AI/Ni and Ni/AI Bilayer Thin Films

1990 ◽  
Vol 202 ◽  
Author(s):  
J. A. Barnard ◽  
E. Haftek ◽  
A. Waknis ◽  
M. Tan
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Electron Diffraction ◽  
Microstructural Evolution ◽  
Interplanar Spacing ◽  
Dc Magnetron Sputtering ◽  
Varying Thickness ◽  
Transmission Electron ◽  
Reverse Sequence ◽  
Carbon Coated

ABSTRACTThe growth and microstructural evolution of Al/Ni and Ni/AI bilayer thin films have been investigated as a function of Al and Ni layer thickness and thermal treatment by transmission electron microscopy. Studies were also made of Al and Ni single layers of varying thickness. All films were grown by dc magnetron sputtering using carbon coated Cu TEM grids as substrates. For the bilayers, the Al thickness was fixed at either 3.5 or 7.0 nm while the Ni thickness was varied systematically from 3.2 to 12.8 nm. Deposition sequence significantly influenced bilayer microstructure even in as-deposited samples. Al/Ni bilayers generally exhibited a finer microstructure than Ni/AI. In the 3.5 nm Al/Ni bilayers no conclusive electron diffraction evidence was found for elemental Al while for the reverse sequence both Al and NiAl3 diffraction rings were found. In the 7.0 nm Al/Ni bilayers diffraction rings due to Al were observed. The reverse sequence again produced both Al and NiAl3 diffraction rings. Interestingly, diffraction rings due to the Ni layers were found for all samples but were consistently measured at positions corresponding to a 2.5–3.5% increase in interplanar spacing. Annealing at 385°C produced evidence for generalized grain growth and strong accentuation of the electron diffraction rings due to the NiAl3 phase. Again, deposition significantly influenced annealed bilayer microstructure. For the Al/Ni sequence annealing produced polycrystalline N1AI3 island-like structures, while for Ni/AI bilayers, annealing promoted the growth of small NiAl3 crystals uniformly distributed in the film.

Microstructural evolution during pyrolysis of triol-based sol-gel single-layer Pb(Zr0.53Ti0.47)O3 thin films

2002 ◽  
Vol 17 (8) ◽  
pp. 2066-2074 ◽  
Author(s):  
Zhaoxia Zhou ◽  
Ian M. Reaney ◽  
David Hind ◽  
Steven J. Milne ◽  
Andy P. Brown ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Microstructural Evolution ◽  
Sol Gel ◽  
Pyrochlore Phase ◽  
Single Layer ◽  
Face Centered Cubic ◽  
Analytical Transmission Electron Microscopy ◽  
Transmission Electron

Advanced analytical transmission electron microscopy has been used to investigate microstructural evolution during pyrolysis in triol-based sol-gel thin films. At pyrolysis temperatures up to 300 °C, the films remained amorphous; however, nanometer-sized precipitates were observed in films heat-treated up to 400 °C for 10 min. Analytical transmission electron microscopy indicated that the precipitates were Pb-rich, as well as deficient in O, Ti, and Zr. Films pyrolyzed up to 500 °C for 10 min were composed of a nanocrystalline pyrochlore phase; however, pores could be observed, situated in the same position as the nanometer-sized precipitates at 400 °C. Face-centered cubic Pb-rich crystallites were also present on the surface of pyrolyzed films but absent in the fully crystallized films annealed at 650 °C. A tentative mechanism is proposed to explain these observations.

Microstructure of SrTiO3 Thin Films as Single Layer and Incorporated in Yba2Cu3O7-x/SrTiO3 Multilayers

1995 ◽  
Vol 401 ◽  
Author(s):  
L. Ryen ◽  
E. Olssoni ◽  
L. D. Madsen ◽  
C. N. L. Johnson ◽  
X. Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Lattice Mismatch ◽  
Single Layer ◽  
Transmission Electron ◽  
Tilt Boundaries ◽  
Interfacial Dislocations ◽  
The Individual ◽  
Film Substrate

AbstractEpitaxial single layer (001) SrTiO3 films and an epitaxial Yba2Cu3O7-x/SrTiO3 multilayer were dc and rf sputtered on (110)rhombohedral LaAIO3 substrates. The microstructure of the films was characterised using transmission electron microscopy. The single layer SrTiO3 films exhibited different columnar morphologies. The column boundaries were due to the lattice mismatch between film and substrate. The boundaries were associated with interfacial dislocations at the film/substrate interface, where the dislocations relaxed the strain in the a, b plane. The columns consisted of individual subgrains. These subgrains were misoriented with respect to each other, with different in-plane orientations and different tilts of the (001) planes. The subgrain boundaries were antiphase or tilt boundaries.The individual layers of the Yba2Cu3O7-x/SrTiO3 multilayer were relatively uniform. A distortion of the SrTiO3 unit cell of 0.9% in the ‘001’ direction and a Sr/Ti ratio of 0.62±0.04 was observed, both in correspondence with the single layer SrTiO3 films. Areas with different tilt of the (001)-planes were also present, within each individual SrTiO3 layer.

Microstructural evolution of dense and porous pyroelectric Pb1−xCaxTiO3 thin films

1999 ◽  
Vol 14 (5) ◽  
pp. 2012-2022 ◽  
Author(s):  
Andreas Seifert ◽  
Laurent Sagalowicz ◽  
Paul Muralt ◽  
Nava Setter
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Microstructural Evolution ◽  
Rutherford Backscattering Spectrometry ◽  
X Ray Diffraction ◽  
Porous Films ◽  
Transmission Electron ◽  
Ca Substitution ◽  
High Figure ◽  
Low Permittivity

Pb1−xCaxTiO3 thin films with x = 0−0.3 for pyroelectric applications were deposited on platinized silicon wafers by chemical solution processing. Ca-substitution for Pb in PbTiO3 results in a reduced c/a ratio of the unit cell, which, in turn, leads to better pyroelectric properties. Control of nucleation and growth during rapid thermal annealing to 650 °C allowed the formation of either highly porous or dense (111) oriented films. The inclusion of pores creates a matrix-void composite with the low permittivity desired for pyroelectric applications, resulting in a high figure of merit. The growth mechanisms for the microstructural evolution of both dense and porous films were analyzed by x-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Rutherford backscattering spectrometry and allowed establishment of microstructure/property relationships.

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

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.

A Technique for the Preparation of Thin-Film Cross-Sections for Transmission Electron Microscopy

1990 ◽  
Vol 199 ◽  
Author(s):  
M. Libera ◽  
T. A. Nguyen ◽  
C. Hwang
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Thin Films ◽  
Data Storage ◽  
Cross Sections ◽  
Film Plane ◽  
Microstructural Study ◽  
Transmission Electron ◽  
Sophisticated Equipment ◽  
Tem Grid

ABSTRACTA number of techniques for producing TEM cross-sections of thin films have been described in recent years as the need for improved and more-thorough microstructural study of thin-film materials has grown. We have developed a method for producing such cross-sections which involves little sophisticated equipment other than an ion mill for thinning. Following the method of Bravman and Sinclair (J. Elec. Micrs. Tech 1,53–61 (1984)), the film of interest is either deposited on or epoxied to a silicon wafer and a composite of six silicon beams (=3mm × 25mm × 0.5mm) is fabricated. Slices are cut from this composite perpendicular to the film plane, and each slice is mechanically thinned by a series of simple grinding and polishing steps to ∼ 50–100μm. Dimpling is not necessary. The specimen is mounted onto a slotted TEM grid which provides a vehicle for safe handling, and the specimen is ion milled to perforation. We have found the technique to be relatively fast, reliable, and simple. Its success hinges on minimizing the amount of direct handling required when the specimen is thin and fragile. We present a detailed recipe describing its various steps and show typical results from studies of thin films for data-storage applications.

Microstructural evolution of ZrO2–HfO2 nanolaminate structures grown by atomic layer deposition

2004 ◽  
Vol 19 (2) ◽  
pp. 643-650 ◽  
Author(s):  
Hyoungsub Kim ◽  
Paul C. McIntyre ◽  
Krishna C. Saraswat
Keyword(s):  
Surface Roughness ◽  
Atomic Layer Deposition ◽  
Microstructural Evolution ◽  
Single Layer ◽  
Atomic Layer ◽  
Individual Layer ◽  
Force Microscopy ◽  
Layer Sequence ◽  
Transmission Electron ◽  
Layer Deposition

Zirconia–hafnia (ZrO2–HfO2) nanolaminate structures were grown using the atomic layer deposition (ALD) technique with different stacking sequences and layer thickness layer thicknesses. The microstructural evolution and surface roughness were compared with those of single-layer ZrO2 or HfO2 films using transmission electron microscopy and atomic force microscopy. Thin single-layer ALD-ZrO2 films were polycrystalline and composed of the tetragonal ZrO2 phase as-deposited, whereas thicker (>14 nm) films were composed mainly of the monoclinic phase. HfO2 films were amorphous as-deposited and crystallized into primarily monoclinic during subsequent anneals at temperatures over 500 °C. All the nanolaminate structures having individual layer thicknesses greater than approximately 2 nm were crystalline (mixture of tetragonal and monoclinic phases) independent of layer sequence and also exhibited a layer-to-layer epitaxy relationship within each grain. However, the identity of the starting layer determined the final grain size and surface roughness of the nanolaminates. A qualitative model for the observed microstructure evolution of the laminate films is proposed.

Crystallographic and Magnetic Properties of CoCrPt Thin Films Investigated Using Single-Crystal Perpendicular Magnetic Thin Film Samples

2002 ◽  
Vol 721 ◽  
Author(s):  
Masaaki Futamoto ◽  
Kouta Terayama ◽  
Katsuaki Sato ◽  
Nobuyuki Inaba ◽  
Yoshiyuki Hirayama
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetic Properties ◽  
Single Crystal ◽  
Film Plane ◽  
Magnetic Thin Film ◽  
X Ray Diffraction ◽  
Easy Magnetization ◽  
Transmission Electron ◽  
Magnetization Axis

AbstractConditions to prepare good single-crystal CoCrPt magnetic thin film with the easy magnetization axis perpendicular to the film plane were investigated using oxide single-crystal substrates, Al2O3(0001), LaAlO3(0001), mica(0001), SrTiO3(111), and MgO(111). The best CoCrPt(0001) single-crystal thin film was obtained on an Al2O3(0001) substrate employing a non-magnetic CoCrRu underlayer. The crystallographic quality of single-crystal thin film was investigated using X-ray diffraction and high-resolution transmission electron microscopy. Some intrinsic magnetic properties (Hk, Ku) were determined for the single-crystal CoCrxPty thin films for a compositional range of x=17-20at% and y=0-17at%.

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