Chemical Treatment Influence on the Glass Substrate to the Growth of V2O5/PANI Thin Film

2009 ◽  
Vol 1230 ◽  
Author(s):  
Elidia M. Guerra ◽  
Mirela C. Santos ◽  
Rodrigo Fernando Bianchi
Keyword(s):  
Thin Film ◽  
Chemical Treatment ◽  
Energy Levels ◽  
Direct Reaction ◽  
Absorption Bands ◽  
Lbl Films ◽  
Ammonia Detection ◽  
Cetyl Pyridinium ◽  
Uv Ozone

AbstractGrowth of the vanadium pentoxide xerogel in the presence of the polyaniline thin film (V2O5/PANI) in different chemical treatment on substrate are presented. The in situ characterization studies revealed the presence of a lamellar structure for the V2O5/PANI hybrid material. The intercalation reaction was evidenced on the basis of the increase in the d-spacing as well as the displacement of the absorption bands toward lower energy levels. The growth of V2O5/PANI thin film, from direct reaction, on glasses substrate using pre-treated with cationic surfactant cetyl pyridinium chloride (CPC) and cetyl trimethylammonium bromide (CTAB) presented layers with a surface homogeneous. The UV/ozone and RCA treatment showed that the film had low adhesion on substrate compared with CPC and CTAB treatment. Furthermore, these results suggests that the CTAB and CPC treatment can be used, further, for V2O5/PANI LbL films using V2O5 gel as first layer as well as a promising candidate for applications as sensor for ammonia detection in poultry shed.

In-Situ Fourier Transform Infrared Spectroscopy for Real-Time Diagnostics of Thin Film Processes

1997 ◽  
Vol 502 ◽  
Author(s):  
P. R. Solomon ◽  
S. Charpenay ◽  
W. Zhang ◽  
A. S. Bonanno ◽  
P. A. Rosenthal ◽  
...  
Keyword(s):  
Thin Film ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Real Time ◽  
Optical Constants ◽  
Fourier Transform Infrared ◽  
Rapid Thermal Anneal ◽  
Absorption Bands ◽  
Infrared Instrumentation

ABSTRACTInfrared spectroscopy is a versatile tool that is well adapted to in-situ diagnostics of many thin film properties and processes. In this paper, we will describe the application of infrared instrumentation for real-time in-situ measurements of film temperature, emissivity, thickness, free carriers, and optical constants using model based spectral analysis. We will illustrate the use of Fourier transform infrared (FT-IR) emission and reflection spectroscopy to monitor the fabrication of stacks of ferroelectric and conductive oxides on silicon substrates during pulsed laser deposition. The ability to measure the infrared optical constants of dielectrics such as silicon dioxide, including the detailed spectral dependence of the vibrational absorption bands at high temperatures, will be presented. The suitability of the technique for real-time sensing during rapid thermal processing will be illustrated using the example of carrier activation during a shallow-junction rapid thermal anneal.

scholarly journals High-κ Dielectric on ReS2: In-Situ Thermal Versus Plasma-Enhanced Atomic Layer Deposition of Al2O3

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1056 ◽  
Author(s):  
Ava Khosravi ◽  
Rafik Addou ◽  
Massimo Catalano ◽  
Jiyoung Kim ◽  
Robert Wallace
Keyword(s):  
Thin Film ◽  
Atomic Layer Deposition ◽  
Photoelectron Spectroscopy ◽  
Atomic Layer ◽  
Ex Situ ◽  
Half Cycle ◽  
Layer Deposition ◽  
Uv Ozone ◽  
Al2o3 Thin Film

We report an excellent growth behavior of a high-κ dielectric on ReS2, a two-dimensional (2D) transition metal dichalcogenide (TMD). The atomic layer deposition (ALD) of an Al2O3 thin film on the UV-Ozone pretreated surface of ReS2 yields a pinhole free and conformal growth. In-situ half-cycle X-ray photoelectron spectroscopy (XPS) was used to monitor the interfacial chemistry and ex-situ atomic force microscopy (AFM) was used to evaluate the surface morphology. A significant enhancement in the uniformity of the Al2O3 thin film was deposited via plasma-enhanced atomic layer deposition (PEALD), while pinhole free Al2O3 was achieved using a UV-Ozone pretreatment. The ReS2 substrate stays intact during all different experiments and processes without any formation of the Re oxide. This work demonstrates that a combination of the ALD process and the formation of weak S–O bonds presents an effective route for a uniform and conformal high-κ dielectric for advanced devices based on 2D materials.

The use of transmission and analytical electron microscopy in studying reactions and phase transformations in thin film

1993 ◽  
Vol 51 ◽  
pp. 842-843
Author(s):  
K. Barmak
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Phase Transformations ◽  
Analytical Electron Microscopy ◽  
Ex Situ ◽  
Multilayer Thin Films ◽  
Absolute Concentration ◽  
Analytical Electron ◽  
Deposition Step

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.

Growth kinetics of Al2Cu in an Al-1.5Cu thin film by in Situ TEM

1993 ◽  
Vol 51 ◽  
pp. 1172-1173
Author(s):  
M. Park ◽  
S.J. Krause ◽  
S.R. Wilson
Keyword(s):  
Thin Film ◽  
In Situ Tem ◽  
Collector Plate ◽  
Transmission Electron ◽  
Device Processing ◽  
Corrosion Susceptibility ◽  
Precipitation Phenomena ◽  
Semiconductor Chips ◽  
Kinetics Of

Cu alloying in Al interconnection lines on semiconductor chips improves their resistance to electromigration and hillock growth. Excess Cu in Al can result in the formation of Cu-rich Al2Cu (θ) precipitates. These precipitates can significantly increase corrosion susceptibility due to the galvanic action between the θ-phase and the adjacent Cu-depleted matrix. The size and distribution of the θ-phase are also closely related to the film susceptibility to electromigration voiding. Thus, an important issue is the precipitation phenomena which occur during thermal device processing steps. In bulk alloys, it was found that the θ precipitates can grow via the grain boundary “collector plate mechanism” at rates far greater than allowed by volume diffusion. In a thin film, however, one might expect that the growth rate of a θ precipitate might be altered by interfacial diffusion. In this work, we report on the growth (lengthening) kinetics of the θ-phase in Al-Cu thin films as examined by in-situ isothermal aging in transmission electron microscopy (TEM).

“In-Situ Raman Spectroscopy of Electronic Processes in Fullerene Thin Films

2002 ◽  
Vol 725 ◽  
Author(s):  
S.B. Phelan ◽  
B.S. O'Connell ◽  
G. Farrell ◽  
G. Chambers ◽  
H.J. Byrne
Keyword(s):  
Thin Film ◽  
Indium Tin Oxide ◽  
Low Temperatures ◽  
In Situ Raman Spectroscopy ◽  
State Reduction ◽  
In Situ Raman ◽  
Linear Behavior ◽  
Current Voltage ◽  
Solid State Reduction

AbstractThe current voltage characteristics of C60 thin film sandwich structures fabricated by vacuum deposition on indium tin oxide (ITO) with an aluminium top electrode are presented and discussed. A strongly non-linear behavior and a sharp increase in the device conductivity was observed at relatively low voltages (∼2V), at both room and low temperatures (20K). At room temperature the system is seen to collapse, and in situ Raman measurements indicate a solid state reduction of the fullerene thin film to form a polymeric state. The high conductivity state was seen to be stable at elevated voltages and low temperatures. This state is seen to be reversible with the application of high voltages. At these high voltages the C60 film was seen to sporadically emit white light at randomly localized points analogous to the much documented Electroluminescence in single crystals.

Reordering and Crystallization of Silicon Carbide Amorphized by Neutron Irradiation

2000 ◽  
Vol 650 ◽  
Author(s):  
Lance L. Snead ◽  
Martin Balden
Keyword(s):  
Thin Film ◽  
Silicon Carbide ◽  
Crystallization Kinetics ◽  
Neutron Irradiation ◽  
Onset Temperature ◽  
Kinetics Of Crystallization ◽  
Crystallization Onset Temperature ◽  
Crystallization Onset ◽  
Kinetics Of

ABSTRACTDensification and crystallization kinetics of bulk SiC amorphized by neutron irradiation is studied. The temperature of crystallization onset of this highly pure, fully amorphous bulk SiC was found to be between 875-885°C and crystallization is nearly complete by 950°C. In-situ TEM imaging confirms the onset of crystallization, though thin-film effects apparently alter the kinetics of crystallization above this temperature. It requires >1125°C for complete crystallization of the TEM foil. Annealing at temperatures between the irradiation and crystallization onset temperature is seen to cause significant densification attributed to a relaxation, or reordering, of the as-amorphized structure.

scholarly journals Unraveling the electrochemical and spectroscopic properties of neutral and negatively charged perylene tetraethylesters

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Christian Wiebeler ◽  
Joachim Vollbrecht ◽  
Adam Neuba ◽  
Heinz-Siegfried Kitzerow ◽  
Stefan Schumacher
Keyword(s):  
Absorption Spectra ◽  
Density Functional ◽  
Energy Levels ◽  
Spectroscopic Properties ◽  
Absorption Bands ◽  
Functional Theory ◽  
Vertical Excitation ◽  
Hartree Fock ◽  
Tauc Plot ◽  
Electrochemical Approach

AbstractA detailed investigation of the energy levels of perylene-3,4,9,10-tetracarboxylic tetraethylester as a representative compound for the whole family of perylene esters was performed. It was revealed via electrochemical measurements that one oxidation and two reductions take place. The bandgaps determined via the electrochemical approach are in good agreement with the optical bandgap obtained from the absorption spectra via a Tauc plot. In addition, absorption spectra in dependence of the electrochemical potential were the basis for extensive quantum-chemical calculations of the neutral, monoanionic, and dianionic molecules. For this purpose, calculations based on density functional theory were compared with post-Hartree–Fock methods and the CAM-B3LYP functional proved to be the most reliable choice for the calculation of absorption spectra. Furthermore, spectral features found experimentally could be reproduced with vibronic calculations and allowed to understand their origins. In particular, the two lowest energy absorption bands of the anion are not caused by absorption of two distinct electronic states, which might have been expected from vertical excitation calculations, but both states exhibit a strong vibronic progression resulting in contributions to both bands.

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