Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : electrical


Preparation and Study the Characteristics of Tungsten Trioxide Thin Films for Gas Sensing Application

Suaad.S.Shaker

Engineering and Technology Journal, 2016, Volume 34, Issue 4, Pages 462-469

In this study, Tungsten Trioxide thin films were successfully synthesized at different substrate temperatures by pulse laser deposition. Structural, morphological and electrical properties of WO3 thin films, were investigated by X-ray diffraction (XRD), Atomic Force Microscope AFM), Scanning Electron Microscope (SEM), Hall Effect and sensing measurements.
The results was indicated that WO3 thin films prepared at 450ᵒC was optimum condition where sensitivity toward H2S gas has been measured, sensitivity was higher than other films preparation at (250ᵒC,350ᵒC) temperature.

Structural and Optoelectronical Properties of In2S3 Thin Films Prepared by CSP Technique for Solar Cell Application

Baha. T. Chiad; M. Sh. Essa; M.D.Abd-aljabar; J.A.Abd-aula

Engineering and Technology Journal, 2014, Volume 32, Issue 4, Pages 629-636

Indium Sulfide In2S3 window layer have been prepared by Chemical Spray Pyrolysis (CSP) at substrate temperate Equal (573 K) from Indium chloride and Thiourea were In/S ratio equal 1.2/8 in the spray solution, the samples prepared with different thicknesses (1.6, 1.7, 2.0 µm), the structural, optical and electrical of these films was investigated at different annealing temperature (Ta).X-ray diffraction studied shows the Structural properties of this layer are polycrystalline with preferred orientation 221, and have good improvement in the crystal structure at the annealing temperature (573K for 1h). The grain size increase with increasing annealing temperature and the optical band gap was found in the range (2.4-2.55 eV) as a function of the film thicknesses and the annealing temperature. Electrical studied of the sprayed and annealed sample shows n-type electrical conductivity, the mobility improved at the annealing temperature equal (573 K) but the resistivity decreased with this temperature.

To Study the Silver Concentration Effect on the Optical and Electrical Properties of the Ag/PMMA Composites

Nahida G.Hamed; Maraw Rahem

Engineering and Technology Journal, 2014, Volume 32, Issue 1, Pages 72-85

The present work was carried out to investigate the silver concentration Effect (Ag %)othe optical and the electrical properties of the polymethyl methacrylate (PMMA). The samples were casted as films from the photopolymer (PMMA) stated above and the reason. The optical constant (α,k,n, εr, and εi)for the photopolymer (PMMA),and Ag/PMMA composites at different concentration were investigated. It was seen that there was nonlinear relationship between the optical constants and the concentration ratio, which was attributed to their incompatibility. These results were confirmed with optical micrographs. It was found that there was increasing of carrier concentration with Ag ratio which Ag/PMMA composites at different concentration. These prepared polymer systems were analyzes spectrophotometically. It was found that an increasing in the absorption spectra with increasing of the silver concentration in Ag/PMMA composites, which was attributed to the increasing in localized states. The results proved that its energy gap was for 13%Ag/PMMA (4.85eV), which was the lowest of all polymer system involved due to previous was caused decreasing in the mobility. The results showed that the best conductivity was at 9%Ag ratio, and the lowest receptivity.