Structures and Properties of C60 & C70 Thin Films Fabricated by Organic MBE

1992 ◽  
Vol 247 ◽  
Author(s):  
K. Tanigaki ◽  
T. Ichihsdhi ◽  
T. W. Ebbesen ◽  
S. Kuroshima ◽  
S. Iijima ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Alkali Halide ◽  
Molecular Motion ◽  
Face Centered Cubic ◽  
Reversible Change ◽  
Structures And Properties ◽  
The Face ◽  
Face Centered ◽  
Substrate Temperatures

ABSTRACTThe C60/C70 thin film crystals have been fabricated on the (001) surface of alkali halide substrates, KC1, KBr, and NaCl, and their structures have been studied. The crystal structure analyses by TEM show that the hexagonal closed packing (hep) with lattice parameters of a=10.0 Å and c=16.3 Å and the face-centered cubic (fee) with a=14.2 Å coexist in the C60 thin film crystals. The C70 thin film crystals show an expanded lattice constant of a=10.5 Å from the view perpendicular to the stacking plane. The ratio of hep to fee is dependent on the kind of the substrates and on the substrate temperatures during the crystal growth. The observed reversible change in the Raman spectrum of the C60 thin films implies a rotational molecular motion in the thin film crystals.

Non-cosine square angular-dependent magnetoresistance of the face-centered-cubic Co thin films

2020 ◽  
Vol 512 ◽  
pp. 167013
Author(s):  
Yu Miao ◽  
Xiaorui Chen ◽  
Shuanglong Yang ◽  
Kun Zheng ◽  
Zhongyuan Lian ◽  
...  
Keyword(s):  
Thin Films ◽  
Face Centered Cubic ◽  
The Face ◽  
Face Centered

Electrodeposition of CuI Thin Film for Perovskite Solar Cells

2020 ◽  
Vol 979 ◽  
pp. 180-184
Author(s):  
I. Karuppusamy ◽  
K. Ramachandran ◽  
S. Karuppuchamy
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Solar Cells ◽  
Applied Voltage ◽  
Perovskite Solar Cells ◽  
Face Centered Cubic ◽  
Applied Potential ◽  
Cathodic Electrodeposition ◽  
Cubic Structure ◽  
Face Centered

The CuI thin film has been successfully prepared by using cathodic electrodeposition method. The synthesized film was characterized using advanced techniques such as XRD, SEM-EDX and UV measurements. The films are crystallized in face centered cubic structure. The crystallinity is increasing for the applied potential of-0.3 V and the crystallinity deteriorates on increasing the potential above - 0.3 V. It was also observed that the applied voltage plays an important role. Homogeneously distributed triangular faceted morphology was observed from SEM. This is consistent with the result of XRD that electrodeposited CuI thin films grow preferential orientation along the (111) crystal plane.

Evolution of the Transrotational Structure During Crystallization of Amorphous Ge2Sb2Te5 Thin Films

2009 ◽  
Vol 1160 ◽  
Author(s):  
Emanuele Rimini ◽  
Riccardo De Bastiani ◽  
Egidio Carria ◽  
Maria Grazia Grimaldi ◽  
Giuseppe Nicotra ◽  
...  
Keyword(s):  
Thin Films ◽  
Film Surface ◽  
Xrd Analysis ◽  
Lattice Parameter ◽  
Cubic Phase ◽  
Face Centered Cubic ◽  
Tem Analysis ◽  
The Face ◽  
Face Centered ◽  
Average Lattice

AbstractThe crystallization of amorphous Ge2Sb2Te5 thin films has been studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The analysis has been performed on partially crystallized films, with a surface crystalline fraction (fS) ranging from 20% to 100%. XRD analysis indicates the presence, in the partially transformed layer, of grains with average lattice parameters higher than that of the equilibrium metastable cubic phase (from 6.06 Å at fS=20% to 6.01 Å at fS=100%). The amorphous to crystal transition, as shown by TEM analysis, occurs through the nucleation of face-centered-cubic crystal domains at the film surface. Local dimples appear in the crystallized areas, due to the higher atomic density of the crystal phase compared to the amorphous one. At the initial stage of the transformation, a fast bi-dimensional growth of such crystalline nucleus occurs by the generation of transrotational grains in which the lattice bending gives rise to an average lattice parameter significantly larger than that of the face-centered-cubic phase in good agreement with the XRD data. As the crystallized fraction increases above 80%, dimples and transrotational structures start to disappear and the lattice parameter approaches the bulk value.

Microstructure and Electrical Properties of Nano Ni-Cr Thin-Films Fabricated by Magnetron Co-Sputtering Techniques

2007 ◽  
Vol 561-565 ◽  
pp. 1201-1204
Author(s):  
Ji Cheng Zhou ◽  
Jian Wu Yan
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Electrical Properties ◽  
Face Centered Cubic ◽  
Temperature Coefficient Of Resistance ◽  
Sputtering Power ◽  
Polycrystalline Microstructure ◽  
Face Centered ◽  
Cr Film ◽  
Resistance Value

The nano Ni-Cr thin-film samples with different composition have been fabricated by a double-target magnetron co-sputtering equipment, through controlling the sputtering power, the substrate rotate speed, and the substrate temperature, The results showed that the grains sizes with polycrystalline microstructure were not greater than 10 nm. The crystal microstructure of Ni-Cr thin-films is Face Centered Cubic (FCC). The dominant texture in the Ni-Cr film was Ni (111) under this sputtering condition. The lattice parameters of Ni crystal and the inter-planar distances of Ni (111) increased by Cr solid-soluble in Ni crystal. The surface morphology of the thin-film samples is smooth and compact. The TCR (temperature coefficient of resistance) value of specimen 3 was 84~130 ppm/k, which show the specimen 3 was the most stable.

A study of interface sliding at F.C.C.-B.C.C. boundaries in a Cu-Zn alloy

1978 ◽  
Vol 36 (1) ◽  
pp. 422-423
Author(s):  
F. Monchoux ◽  
A. Rocher ◽  
J.L. Martin
Keyword(s):  
Face Centered Cubic ◽  
Creep Tests ◽  
High Voltage Electron Microscopy ◽  
Diffusion Treatment ◽  
Voltage Electron ◽  
The Face ◽  
Face Centered ◽  
Interface Sliding ◽  
Zn Alloy ◽  
Made In

Interphase sliding is an important phenomenon of high temperature plasticity. In order to study the microstructural changes associated with it, as well as its influence on the strain rate dependence on stress and temperature, plane boundaries were obtained by welding together two polycrystals of Cu-Zn alloys having the face centered cubic and body centered cubic structures respectively following the procedure described in (1). These specimens were then deformed in shear along the interface on a creep machine (2) at the same temperature as that of the diffusion treatment so as to avoid any precipitation. The present paper reports observations by conventional and high voltage electron microscopy of the microstructure of both phases, in the vicinity of the phase boundary, after different creep tests corresponding to various deformation conditions.Foils were cut by spark machining out of the bulk samples, 0.2 mm thick. They were then electropolished down to 0.1 mm, after which a hole with thin edges was made in an area including the boundary

Electron diffraction detection of ordliking in annealed PbTe thin film

1990 ◽  
Vol 48 (4) ◽  
pp. 1018-1019
Author(s):  
Karimat El-Sayed
Keyword(s):  
Thin Film ◽  
Electron Diffraction ◽  
Lead Telluride ◽  
Structural Basis ◽  
Face Centered Cubic ◽  
X Ray ◽  
Polycrystalline Thin Films ◽  
Stage Process ◽  
Diffraction Patterns ◽  
Face Centered

Lead telluride is an important semiconductor of many applications. Many Investigators showed that there are anamolous descripancies in most of the electrophysical properties of PbTe polycrystalline thin films on annealing. X-Ray and electron diffraction studies are being undertaken in the present work in order to explain the cause of this anamolous behaviour.Figures 1-3 show the electron diffraction of the unheated, heated in air at 100°C and heated in air at 250°C respectively of a 300°A polycrystalline PbTe thin film. It can be seen that Fig. 1 is a typical [100] projection of a face centered cubic with unmixed (hkl) indices. Fig. 2 shows the appearance of faint superlattice reflections having mixed (hkl) indices. Fig. 3 shows the disappearance of thf superlattice reflections and the appearance of polycrystalline PbO phase superimposed on the [l00] PbTe diffraction patterns. The mechanism of this three stage process can be explained on structural basis as follows :

scholarly journals Effects of Perpendicular Magnetic Field Annealing on the Structural and Magnetic Properties of [Co/Ni]2/PtMn Thin Films

2021 ◽  
Vol 7 (3) ◽  
pp. 38
Author(s):  
Roshni Yadav ◽  
Chun-Hsien Wu ◽  
I-Fen Huang ◽  
Xu Li ◽  
Te-Ho Wu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Magnetic Properties ◽  
Photoelectron Spectroscopy ◽  
Perpendicular Magnetic Field ◽  
Face Centered Cubic ◽  
Lattice Image ◽  
X Ray ◽  
Field Annealing ◽  
Face Centered

In this study, [Co/Ni]2/PtMn thin films with different PtMn thicknesses (2.7 to 32.4 nm) were prepared on Si/SiO2 substrates. The post-deposition perpendicular magnetic field annealing (MFA) processes were carried out to modify the structures and magnetic properties. The MFA process also induced strong interlayer diffusion, rendering a less sharp interface between Co and Ni and PtMn layers. The transmission electron microscopy (TEM) lattice image analysis has shown that the films consisted of face-centered tetragonal (fct) PtMn (ordered by MFA), body-centered cubic (bcc) NiMn (due to intermixing), in addition to face-centered cubic (fcc) Co, Ni, and PtMn phases. The peak shift (2-theta from 39.9° to 40.3°) in X-ray diffraction spectra also confirmed the structural transition from fcc PtMn to fct PtMn after MFA, in agreement with those obtained by lattice images in TEM. The interdiffusion induced by MFA was also evidenced by the depth profile of X-ray photoelectron spectroscopy (XPS). Further, the magnetic properties measured by vibrating sample magnetometry (VSM) have shown an increased coercivity in MFA-treated samples. This is attributed to the presence of ordered fct PtMn, and NiMn phases exchange coupled to the ferromagnetic [Co/Ni]2 layers. The vertical shift (Mshift = −0.03 memu) of the hysteresis loops is ascribed to the pinned spins resulting from perpendicular MFA processes.

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