Top PDF Optical and Electrical Properties of Thin Films of Polyaniline and Polypyrrole

Optical and Electrical Properties of Thin Films of Polyaniline and Polypyrrole

Optical and Electrical Properties of Thin Films of Polyaniline and Polypyrrole

solutions were degassed by argon bubbling for 10 min duration, the period of synthesis was 20 minutes, similar concentrations of aniline and salt were used for the polymerization of polyaniline films. The oxidation potential values between working and counter electrodes were 5 and 7V for pyrrole and aniline, respectively, the current increases sharply and stabilizes after some minutes at values of 13.8 mA/cm 2 and 27 mA/cm 2 for pyrrole and aniline respectively, the working electrode surface then becomes covered by black and dark blue for polypyrrole and polyaniline, respectively. This electrochemical polymerization gives us p-type films, it’s an easy matter to dope or dedope the samples using chemical or electrochemical technique, for undoped samples, it’s quite enough to be dope them by chemical methods “treated with the vapor of the dopant at room temperature for 1 hours”. The dopants could be I 2 , Br 2 , AsF 5 etc. For example, I 2 is a good material for vapor phase
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Indium Doped Zinc Oxide Thin Films: Effect on Structural, Optical and Electrical Characteristics

Indium Doped Zinc Oxide Thin Films: Effect on Structural, Optical and Electrical Characteristics

optical and electrical properties of Zinc oxide thin films (IZO) prepared through spray pyrolysis method is reported. The dopant concentration was varied as 1, 2, 5 and 7.5 taken in mole percentage. XRD analysis show that the average grain size of IZO thin films decreases as the dopant concentration increases. When doped heavily, the optical band gap (Eg) was found to increase from 3.06 eV to 3.6 eV, which is due to Burstein-Moss effect. The optical constants such as refractive index (n) and extinction co-efficient (k) are calculated from the reflectance and UV-absorbance data respectively. FTIR studies revealed the formation of Zn-O bond at 489 cm -1 .The
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Effects of Laser Radiation on the Optical and Electrical Properties of ITO Thin Films Deposited by RF Sputtering

Effects of Laser Radiation on the Optical and Electrical Properties of ITO Thin Films Deposited by RF Sputtering

Surface morphology, optical and electrical properties of the as-deposited and irradiated ITO thin films samples were characterized accordingly. One of the important and useful techniques used for the analysis of the surface morphology of thin films materials is atomic force microscopy. Fig. 1 shows three dimensional (3D) AFM images of ITO films with and without Nd:YAG laser energy treatment scanned over 5 μm × 5 μm area. The morphological parameters of the treated and untreated ITO films were tabulated in Table 1. A careful study of these images in Fig. 1 and Table 1 indicates the dependance of ITO films surface morphology on the amount of laser energy exposed on their respective surfaces. The grain size, as well as the respective roughness of the treated samples, increased significantly when the applied laser radiation value is increased due to laser heat absorption. This causes the grain to expand and agglomerate resulting in rougher surface. The large grain size decreases the grain boundary scattering which subsequently improves the carrier mobility of the ITO films. Some larger dots with white spots are seen on the surface of the treated ITO films. Generally, the regular grain growth of morphological features of the treated samples with dips, cavities surface pattern aided the surface roughness[24]. As seen in Table 1 smaller root means square R q and average R a roughness
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Temperature Dependent Properties of Spray Deposited Nanostructured ZnO Thin Films

Temperature Dependent Properties of Spray Deposited Nanostructured ZnO Thin Films

The quality and properties of the spray deposited film highly depends on the various process parameters such as spray rate, substrate temperature, nozzle to substrate distance, quantity of spray solution, and precursor concentration. However, the most important parameter is the substrate temperature as it highly affects the film morphology. The higher the substrate temperature, the rougher and more porous are the films. If the temperatures are too low the films are cracked. In between, dense and smooth films can be obtained. The deposition temperature also influences the crystallinity, texture and other physical properties of the deposited films. The present study is focused on the influence of substrate temperature on structural, optical and electrical properties of zinc oxide films deposited by spray pyrolysis technique.
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Optical and Electrical Properties of Vacuum Evaporated Sexithiophene Thin Films

Optical and Electrical Properties of Vacuum Evaporated Sexithiophene Thin Films

From the absorption spectrum of sexithiophene thin layer, it may be noted that the 6T does not absorb light at low energies (long wavelengths) and the absorption edge is located around 550 nm. A more detailed representation of energy by adjusting the absorption bands by Gaussian functions, shows that the absorption edge is located exactly at 2.24 eV which corresponds to the optical gap of 6T. It is noted that the energy gap between the replicas vibronic 0.17 which is equivalent to the energy of vibration C=C binding. On the other hand, the transition to the high level of the bursting of Davydov is located 3,37 eV .
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Optical and Electrical Properties of Pbs Thin Films Grown by Chemically Bath Deposition [CBD] at Different Lead Concentrations

Optical and Electrical Properties of Pbs Thin Films Grown by Chemically Bath Deposition [CBD] at Different Lead Concentrations

The deposition of PbS films was done in a reactivechemical bath prepared in a 100 ml beaker by asequentialaddition of solutions of 5 ml of 0.5 M lead nitrate as a source of Pb +2 , 5 ml of 2 Msodium hydroxide as source of alkaline medium, 6 ml of 1 M thiourea as source of S -2 and 2 ml of 1M tri-ethanolamine as a complexing agent. Solutions of 1M thiourea, 1M tri-ethanolamine and 1M sodium hydroxide were preparedfrom analytical grade chemicals. Lead nitrate solutions of varying concentration from 0.3M to 0.7M at intervals of 0.1M were also prepared. 5ml of lead nitrate was measured and poured into a 100ml beaker followed by 5ml of 2M sodium hydroxide and the mixture was thoroughly stirred using an electric stirrer to obtain a milky solution. This was followed by adding 6ml of 1M thiourea followed immediately by 2ml of 1M tri-ethanolamine while stirring continued for about two minutes to ensure uniformity of the mixture. The solution was topped with de-ionized water to a volume of 100 ml while stirring. A glass slide substrate was then inserted vertically leaning on the side of the beaker and the set up was maintained at room temperature for 120 minutes. Lead nitrate concentration was varied at intervals of 0.1 for the subsequent films from 0.3 - 0.7M of Pb +2 ion concentrations. Three substrates were vertically immersed intothe bath each time and remained undisturbed for 120 min and then subsequently retired from the bath atthe same time,cleaned and kept in a dark place for analysis. The resultant films were homogeneous, welladhered to the substrate, and specularly reflecting.Reflection and transmission spectra weremeasured at room temperature in the spectral range of 260–2000 nm (4.54–1.08eV)using NIR-VIS IR spectrophotometer DUC 3700instrument at ambient temperature. The electrical resistivity measurements were done using the Keithley2400 source meter interfaced with a computer.
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Optical and Electrical Properties of Cu-Based Thin Films by Aerosol Assisted Chemical Vapor Deposition

Optical and Electrical Properties of Cu-Based Thin Films by Aerosol Assisted Chemical Vapor Deposition

[12] Mugwang’a, FK, Karimi, PK, Njoroge, WK, Omayio, O, & Waita, SM. (2013). Optical characterization of Copper Oxide thin films prepared by reactive dc magnetron sputtering for solar cell applications. International Journal of Thin Films Science and Technology, 2, 15–24.

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Electrical and Optical Properties of IrO2 Thin Films Prepared by Laser ablation

Electrical and Optical Properties of IrO2 Thin Films Prepared by Laser ablation

thin films during the sputtering. The tapping mode AFM images were taken using a Digital Instruments Nanoscope III, multimode atomic force microscope. An Si tip with end tip diameter of 5–10 nm and 300 kHz resonant oscillating frequency were used for the tapping mode imaging. The resistivity was measured in the temperature range from 100 to 773 K by a van der Pauw method. The optical transmission was studied by using a UV-VIS-NIR spectrophotometer (Shimadzu UV-3101PC).

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Role of Substrate Temperatures on Structural, Optical, Wetting and Electrical Transport Properties of CdS Thin Films

Role of Substrate Temperatures on Structural, Optical, Wetting and Electrical Transport Properties of CdS Thin Films

recorded by UV-VIS double beam spectrophotometer in the range of 300 - 950 nm at room temperature. Figure 5 shows the variation of optical transmittance with wave- length. The optical study shows that the films are absorp- tive. The value of absorption coefficient is depending upon radiation energy as well as the composition of films. The optical band gaps of the CdS films are found to de- crease (from 2.41 eV to 2.39 eV) with increase in sub- strate temperatures shown in Figure 6. This is due to the increase of grain size on increase in substrate tempera- tures [7]. The plots of (αhν) 2 vs hν are linear in high en-
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Effects of Al Doping on the Properties of ZnO Thin Films Deposited by Atomic Layer Deposition

Effects of Al Doping on the Properties of ZnO Thin Films Deposited by Atomic Layer Deposition

The tuning of structural, optical, and electrical properties of Al-doped ZnO films deposited by atomic layer deposition technique is reported in this work. With the increasing Al doping level, the evolution from (002) to (100) diffraction peaks indicates the change in growth mode of ZnO films. Spectroscopic ellipsometry has been applied to study the thickness, optical constants, and band gap of AZO films. Due to the increasing carrier concentration after Al doping, a blue shift of band gap and absorption edge can be observed, which can be interpreted by Burstein-Moss effect. The carrier concentration and resistivity are found to vary significantly among different doping concentration, and the optimum value is also discussed. The modulations and improvements of properties are important for Al-doped ZnO films to apply as transparent conductor in various applications.
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Investigation of the structural, optical and electrical properties of Cu3BiS3 semiconducting thin films

Investigation of the structural, optical and electrical properties of Cu3BiS3 semiconducting thin films

The XRD spectrum of the film shows a clear pattern of single phase orthorhombic lattice structure, as shown in Fig.3(a). A number of extra peaks, associated with metallic molybdenum and bismuth are also observed, indicating the presence of Bi clusters. Raman spectra, measured at different points of the films at room temperature, consistently reveal four modes at 96, 125, 264 and 292 cm -1 as shown in Fig. 3(b). The dominant peak at 292 cm -1 has a full width at half maximum (FWHM) of 12 cm -1 .

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Structural and Optical Properties of ZnO Thin Films Deposited by Pyrolysis Spray Method: Effect of Substrate Temperature

Structural and Optical Properties of ZnO Thin Films Deposited by Pyrolysis Spray Method: Effect of Substrate Temperature

Abstract: During the last decades, thin films of ZnO have given rise to a great interest, as transparent conducting oxides. This is due the optical and electrical properties of zinc oxide; it’s very high thermal and chemical stability, its non-toxicity as well as his abandonment in nature. The transparent conducting ZnO thin films were deposited on glass substrate by pyrolysis spray technique. Zinc acetate was used as starting solution with a molarity of 0.1 M. The structural and optical properties of the ZnO thin films were studied as a function of the substrate temperatures in the range of 100 to 400°C. Structural properties have been studied by X-ray diffraction (XRD) technique. The preferred orientation for ZnO thin films lies along (002) direction. From XRD data, the average crystallite size is determined from scherrer formula. The grain size is in the range of 10~27. The transmittance of the films is enhanced from 60 to 85% in the visible region in the range from 400 to 1100 nm by increasing the substrate temperature. The optical band gap energy attenuates from 3.67 to 3.25eV and whereas the Urbach energies of the films increase from 226 to 91.2 meV with increasing the substrate temperature from 100°C to 400°C.
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Structural, optical, electrical and resistive switching properties of ZnO thin films deposited by thermal and plasma-enhanced atomic layer deposition

Structural, optical, electrical and resistive switching properties of ZnO thin films deposited by thermal and plasma-enhanced atomic layer deposition

Owing to its excellent properties and abundance of the raw material, ZnO is a very attractive and prospective material for optoelectronic, electronic and piezoelectric device applications. 1 Various ZnO-based devices and microsystems have been developed such as ultraviolet light emitting diodes 2 , piezoelectric transducers 3 , transparent electronics 4 and so on. Various methods including sputtering(ref), pulsed laser deposition (PLD) (ref), chemical vapor deposition (CVD) (ref), spray pyrolysis and sol-gel process(ref) have been developed to deposit ZnO thin films. Generally, electrical and optical properties of ZnO films strongly depend on growth techniques and conditions, therefore it is very important to identify right growth technique for each application. 5-7
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Study of optical and electrical properties of cdznse2 thin films deposited at different substrate temperatures by spray pyrolysis technique

Study of optical and electrical properties of cdznse2 thin films deposited at different substrate temperatures by spray pyrolysis technique

substrate by spray pyrolysis technique and effect of substrate temperature on optical and electrical properties was studied successfully. Optical studies shows that films are highly absorptive in nature having high absorption coefficient. The optical band gap was found to be 2.04 eV at substrate temperature 300°C bolow and above which optical band gap increases. EDAX analysis shows the presence of Cd, Zn and Se elements in thin films.SEM analysis shows the presence of nanotubes. The electrical studies reveals that the conductivity of CdZnSe 2 thin films increases with substrate temperature as
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Effect of substrate temperature on optical and electrical properties of CdZnSeTe thin films prepared by spray pyrolysis technique

Effect of substrate temperature on optical and electrical properties of CdZnSeTe thin films prepared by spray pyrolysis technique

The temperature of substrate which are in the form of double washed and then heated biological glass plates. The temperature of the substrate was maintained at 300°C and was measured by a pre-calibrated copper constantan thermo- couple. The solution was sprayed at a pressure of 12 Kg/cm 2 . The glass sprayer was mechanically moved to and fro during spraying to avoid the formation of droplets on the hot substrate and ensure instant evaporation. The spray rate was maintained at 3.5 ml/min. The thickness of the films was measured by weighing method and Michelson interferometer. The only difference between these two methods is of the order of 0.003μm. Transmission was taken on UV-1800 Shimadzu spectrophotometer in the wavelength range 350nm-1100nm. Electrical conductivity was measured by four probe method. Chemical composition analysis of the film was tested by EDAX analysis. The surface morphologies of as deposited CdZnSeTe thin films were carried out by scanning electron microscope.
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1.
													Structural and electrical properties of   sns thin films via   chemical bath deposition technique

1. Structural and electrical properties of sns thin films via chemical bath deposition technique

Chemical deposition method is based on a chemical reaction between dissolved precursors in aqueous solution. Tin sulphide films were deposited on microscope slide from bath solution which contains stannous chloride, glacial acetic acid, tri-ethanol amine and thioacetamide. Stannous chloride and thioacetamide were used to provide the tin ions and sulphur ions respectively. Mean while triethanolamine was used as the complex agent to prolong the life time of the long deposition bath besides enhancing the adhesion of the deposition films on the optical microscope slide. Analysis of the data given in table1reveal that the films deposited using 0.1m Sncl 2 produce thinner films while higher concentration Sncl 2 solution (0.3m)
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Study of Electrical Optical and Structural Properties of Lead Selenide Sulphide Ternary Thin Films

Study of Electrical Optical and Structural Properties of Lead Selenide Sulphide Ternary Thin Films

Polycrystalline Lead Selenide Sulphide thin films have been deposited on glass substrate at 300 K by thermal evaporation technique. The different sets of samples of varying composition ‘x’ from 0.1 to 0.9 were deposited and annealed at reduced pressure of 0.1 micron for duration of 4 hours at temp (373) K. The material parameters determined are bulk resistivity 1.450 (Ohm-cm), mean free path 2820 Å and carrier concentration 5.5 x 10 12 per cm 3 . The estimated activation energy for heating

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Study Of Electrical And Optical Properties Of Thin Films

Study Of Electrical And Optical Properties Of Thin Films

For Fluorine-Doping Ammonium Fluoride (NH4F) disintegrated in doubly refined water was added to the starting arrangement. Though for Antimony-Doping Antimony-Trichloride (SbCl3) broke up in isopropyl liquor was included. The general measure of arrangement for each situation was set up to 50 ml and a similar measure of arrangement was showered on pre-warmed substrates. The rehashed analyses of every affidavit demonstrated that the films could be repeated effortlessly. A broad care was taken in giving adequate splash interim between progressive showers for the substrates return to statement temperature in the wake of experiencing warm deterioration. This has brought about the best possible decay of the films that thus delivered the most minimal ever sheet opposition esteems revealed for the doped SnO 2 films from SnCl2 antecedent. The
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Enhancement of optical and electrical properties of zno thin films using indium doping

Enhancement of optical and electrical properties of zno thin films using indium doping

was made in a solvent containing methanol, water and acetic acid in a ratio 65:25:10. Same solvent was used to prepare 0.2 molar indium acetate solution. The indium acetate solution was added to zinc acetate solution in calculated amount to achieve indium doping and the solution was stirred well ultrasonically before deposition. Five batches of solutions were made with various indium content (0,2,4,6 and 8 at%). The solutions were sprayed to cleaned fused silica substrate at 400 0 C with air as carrier gas using Holmarc HO-TH-04 automated spray pyrolysis equipment. Optimized spray parameters such as substrate distance (15cm) and solution flow rate nute) were kept constant for all samples. The spray nozzle was symmetrically moved parallel to the substrate surface throughout the deposition process to achieve uniform allowed to cool after deposition and C in a high vacuum of 10 -5 mbar for two hours. ZnO films with five different indium doping levels prepared and were named IZO-0, -8 respectively. The thicknesses of the films were measured using spectroscopic ellipsometric technique with Angstrom Sun Technologies Inc. SR-200. The X ray diffraction profiles of the samples were recorded using ray diffractometer (Cu-Kα-radiation – ). The electrical properties of the films were studied using Van der Pauw four probe method (ECOPIA HMS 3000 Hall measurement system). UV- Visible spectroscopy was employed to study the optical transparency of the films (Perkin Elmer Lambda 35). The data from transparency measurement INTERNATIONAL JOURNAL OF CURRENT RESEARCH
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Study of Structural Properties of Annealed CdO and ZnO thin films

Study of Structural Properties of Annealed CdO and ZnO thin films

Figure 1 show the X- Ray diffraction pattern of CdS thin film obtained using X-Ray generated at 40kv energy and 15mA current without filter. SC 70 detector with the continuous scan mode was used. Qualitative Analysis Result shows that the Phase Name of the film is Greenokite with the formula CdS having DB Card number 1011054. The peak list of the CdS sample is shown in table 1 13,14 .

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