Growth Front Roughening of Room Temperature Deposited Oligomer Thin Films

2000 ◽  
Vol 648 ◽  
Author(s):  
D. Tsamouras ◽  
G. Palasantzas ◽  
J. Th. M. De Hosson ◽  
G. Hadziioannou
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Room Temperature ◽  
Growth Front ◽  
Silicon Substrates ◽  
Height Distribution ◽  
Force Microscopy ◽  
Atomic Force ◽  
Roughness Amplitude ◽  
Non Gaussian

AbstractGrowth front scaling aspects are investigated for PPV-type oligomer thin films vapor- deposited onto silicon substrates at room temperature. For film thickness d~15-300 nm, commonly used in optoelectronic devices, correlation function measurement by atomic force microscopy yields roughness exponents in the range H=0.45±0.04, and an rms roughness amplitude which evolves with film thickness as a power law σ∝ dβ with β=0.28±0.05. The non-Gaussian height distribution and the measured scaling exponents (H and β) suggest a roughening mechanism close to that described by the Kardar-Parisi-Zhang scenario.

Heteroepitaxial Growth of Epitaxial C60-Thin Films on Mica(001)

1994 ◽  
Vol 359 ◽  
Author(s):  
S. Henke ◽  
K.H. Thürer ◽  
S. Geier ◽  
B. Rauschenbach ◽  
B. Stritzker
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Substrate Temperature ◽  
Room Temperature ◽  
Heteroepitaxial Growth ◽  
X Ray Diffraction ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Substrate Temperatures

ABSTRACTOn mica(001) thin C60-films are deposited by thermal evaporation at substrate temperatures from room temperature up to 225°C. The dependence of the structure and the epitaxial alignment of the thin C60-films on mica(001) on the substrate temperature and the film thickness up to 1.3 μm at a well-defined deposition rate (0.008 nm/s) is investigated by atomic force microscopy and X-ray diffraction. The shape and the size of the C60-islands, which have an influence on the film quality at larger film thicknesses, are sensitively dependent on the substrate temperature. At a film thickness of 200 nm the increase of the substrate temperature up to 225°C leads to smooth, completely coalesced epitaxial C60-thin films characterized by a roughness smaller than 1.5 nm, a mosaic spread Δω of 0.1° and an azimuthal alignment ΔΦ of 0.45°.

Anisotropic Behaviour of Surface Roughening in Lattice Mismatched Heteroepitaxial Thin Films

1996 ◽  
Vol 436 ◽  
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.

Reactive Sputtering Growth and Characterizations of InN Thin Films on Si Substrates

2012 ◽  
Vol 545 ◽  
pp. 290-293
Author(s):  
Maryam Amirhoseiny ◽  
Hassan Zainuriah ◽  
Ng Shashiong ◽  
Mohd Anas Ahmad
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Rf Magnetron Sputtering ◽  
Rf Power ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
X Ray ◽  
Force Microscopy ◽  
Si Substrates ◽  
Atomic Force

We have studied the effects of deposition conditions on the crystal structure of InN films deposited on Si substrate. InN thin films have been deposited on Si(100) substrates by reactive radio frequency (RF) magnetron sputtering method with pure In target at room temperature. The nitrogen gas pressure, applied RF power and the distance between target and substrate were 2×10-2 Torr, 60 W and 8 cm, respectively. The effects of the Ar–N2 sputtering gas mixture on the structural properties of the films were investigated by using scanning electron microscope, energy-dispersive X-ray spectroscopy, atomic force microscopy and X-ray diffraction techniques.

scholarly journals Optical and Morphological Studies of Thermally Evaporated PTCDI-C8 Thin Films for Organic Solar Cell Applications

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Ronak Rahimi ◽  
V. Narang ◽  
D. Korakakis
Keyword(s):  
Thin Films ◽  
Silicon Substrates ◽  
High Electron ◽  
Ambient Conditions ◽  
Force Microscopy ◽  
Morphological Studies ◽  
Atomic Force ◽  
Organic Semiconductor Devices ◽  
Thermal Evaporator ◽  
High Degree

PTCDI-C8 due to its relatively high photosensitivity and high electron mobility has attracted much attention in organic semiconductor devices. In this work, thin films of PTCDI-C8 with different thicknesses were deposited on silicon substrates with native silicon dioxide using a vacuum thermal evaporator. Several material characterization techniques have been utilized to evaluate the structure, morphology, and optical properties of these films. Their optical constants (refractive index and extinction coefficient) have been extracted from the spectroscopic ellipsometry (SE). X-ray reflectivity (XRR) and atomic force microscopy (AFM) were employed to determine the morphology and structure as well as the thickness and roughness of the PTCDI-C8 thin films. These films revealed a high degree of structural ordering within the layers. All the experimental measurements were performed under ambient conditions. PTCDI-C8 films have shown to endure ambient condition which allows pots-deposition characterization.

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

2004 ◽  
Vol 19 (8) ◽  
pp. 2315-2321 ◽  
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.

Electroplated CuO Thin Films from High Alkaline Solutions

2011 ◽  
Vol 15 (1) ◽  
pp. 49-55
Author(s):  
V. Dhanasekaran ◽  
T. Mahalingam ◽  
S. Rajendran ◽  
Jin Koo Rhee ◽  
D. Eapen
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Film Thickness ◽  
Structural Characteristics ◽  
Band Gap Energy ◽  
Alkaline Solutions ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Microstructural Parameters ◽  
Atomic Force

CuO thin films were coated on ITO substrates by an electrodeposition route through potentiostatic mode. The electrodeposited CuO thin films were characterized and the role of copper sulphate concentration on the structural, morphological and optical properties of the CuO films was studied. Film thickness was measured by a stylus profilometer and found to be in the range between 800 and 1400 nm. The structural characteristics studies were carried out using X-ray diffraction and found that the films are polycrystalline in nature with a cubic structure. The preferential orientation of CuO thin films is found to be along (111) plane. The estimated microstructural parameters revealed that the crystallite size increases whereas the number of crystallites per unit area decreases with increasing film thickness. SEM studies show that the grain sizes of CuO thin films vary between 100 and 150 nm and also morphologies revealed that the electrodeposited CuO exhibits uniformity in size and shape. The surface roughness is estimated 15 nm of the CuO film were studied by atomic force microscopy. Optical properties of the films were analyzed from absorption and transmittance studies. The optical band gap energy was determined to be 1.5 eV from absorption coefficient. The variation of refractive index (n), extinction coefficient (k), with wavelength was studied and the results are discussed.

Magnetic Films of Cobalt/Aluminum Electrodeposited from the Room Temperature Molten Salts AlCl3-BPC-CoCl2

2004 ◽  
Vol 59 (5) ◽  
pp. 519-524 ◽  
Author(s):  
Chao-Chen Yang ◽  
Te-Ho Wu ◽  
Min-Fong Shu
Keyword(s):  
Thin Films ◽  
Magnetic Force Microscopy ◽  
Room Temperature ◽  
Magnetic Force ◽  
Current Method ◽  
Magnetic Films ◽  
Deposition Potential ◽  
Force Microscopy ◽  
Atomic Force ◽  
Increasing Temperature

Abstract The electric conductivities of molten mixtures of aluminum chloride-butylpyridinium chloridecobalt chloride (AlCl3-BPC-CoCl2) were measured using a computerized direct-current method. The conductivities of all the melts increased with increasing temperature. The electrodeposition of Co/Al films from the AlCl3-BPC melt containing a small amount of CoCl2 has been studied by cyclic voltammetry. Compact and smooth Co/Al thin films could be obtained at a deposition potential of −0.4 V. The surface morphology and the composition of the electrodeposited thin films were studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The magnetic properties of the deposited thin films have been investigated via magnetic force microscopy (MFM) and vibrating sample magnetometry (VSM). Higher magnetization and smooth domains of Co/Al layers could be obtained at the deposition potentials of −0.1 V and −0.4 V, respectively.

Deposition and Characterization of MgO Thin Films on SrTiO3 and LaAlO3 Substrates

1992 ◽  
Vol 280 ◽  
Author(s):  
Bertha P. Chang ◽  
Neville Sonnenberg ◽  
Michael J. Cima
Keyword(s):  
Thin Films ◽  
Film Thickness ◽  
Grazing Incidence ◽  
Rf Magnetron Sputtering ◽  
Electron Beam Evaporation ◽  
Substrate Material ◽  
X Ray ◽  
Force Microscopy ◽  
Atomic Force ◽  
Surface Morphologies

ABSTRACTMgO thin films have been deposited on SrTiO3 and LaA1O3 substrates using both off-axis rf magnetron sputtering and electron beam evaporation techniques. The effects of substrate material, temperature, film thickness, deposition rate, sputtering gas, and pressure on the quality of the MgO films produced have been studied. Films deposited on (100) SrTiO3 at temperatures > 300°C display only the (h00) reflections in their X-ray diffraction traces, with narrow X-ray rocking curve measurements indicating that these films are epitaxial. Epitaxy has been confirmed with grazing incidence diffraction. MgO films deposited on (100) LaAlO3 are crystalline, but have varying orientations depending on the film thickness. From scanning electron microscopy, MgO films on SrTiO3 substrates appear smooth and dense while those deposited on LaAlO3 substrates possess rougher surfaces. Surface morphologies have been analyzed using atomic force microscopy.

scholarly journals Morphology and Spectroscopic Ellipsometry of PMMA Thin Films

2017 ◽  
Vol 9 (2) ◽  
pp. 5 ◽  
Author(s):  
H. M. El-Nasser
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Spectroscopic Ellipsometry ◽  
Silicon Substrates ◽  
Analysis Method ◽  
Force Microscopy ◽  
Atomic Force ◽  
Mean Grain Size ◽  
Multiple Sample ◽  
Ellipsometry Data

The morphology and optical properties of PMMA thin films deposited on silicon substrates were investigated. The spin coated films were characterized by atomic force microscopy and spectroscopic ellipsometry. Regardless that, the samples were deposited at different coating speeds, the surface structures of all PMMA thin films were consistent, and found to be relatively smooth, with a mean grain size in the range of 13-25 nm. The refractive index as well as the extinction coefficient of the films was determined using spectroscopic ellipsometry data over the wavelength range 380-750 nm. For this purpose, we used the Cauchy dispersion relation in order to represent PMMA layers, and then models were built by adding a roughness layer, which simply corrects any possible deviation from planarity. Besides, the thicknesses of all four films were calculated simultaneously based on multiple sample analysis method. By using this method, optical properties were coupled in such way that, the optical constants for all samples were assumed to be identical.

Atomic force microscopy study of small-size nanotubular polymer thin films

1999 ◽  
Vol 14 (3) ◽  
pp. 1084-1090 ◽  
Author(s):  
C. F. Zhu ◽  
I. Lee ◽  
J. W. Li ◽  
C. Wang ◽  
X. Y. Cao ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Dynamics ◽  
Atomic Force Microscopy ◽  
Room Temperature ◽  
Polymer Thin Films ◽  
Microscopy Study ◽  
Atomic Force Microscopy Study ◽  
Contact Mode ◽  
Force Microscopy ◽  
Atomic Force

In this paper, we report atomic force microscopy (AFM) images of a tubular polymer and its supermolecular polymer thin films, operated in contact mode at room temperature in air. The configuration models are also calculated using molecular dynamics. The diameter of the polymer nanotube is about 0.7 nm, the smallest size a tube can have. The results of calculation agree with the experimental results.

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