Barrier inhomogeneities of Al/p-In2Te3 thin film Schottky diodes

The current-voltage (I-V) and capacitance-voltage (C-V) characteristics of p-In2Te3/Al thin films Schottky diodes papered by Flash Evaporation technique were measured in the temperature range 303-335 K have been interpreted on the basis of the assumption of a Gaussian distribution of barrier heights (φbo) due to barrier height inhomogeneities that prevail at the interface. It has been found that the occurrence of Gaussian distribution of BHs is responsible for the decrease of the apparent BH (φbo) and increase of the ideality factor (η). The inhomogeneities are considered to have a Gaussian distribution with a mean barrier height of (φbm) and standard deviation (σs) at zero-bias. Furthermore, the activation energy value (φb) at T = 0 and Richardson constant (A**) value was obtained as 0.587 eV and 3.09 Acm– 2 K– 1 by means of usual Richardson plots. Hence, it has been concluded that the temperature dependence of the I-V characteristics of p-In2Te3/Al Schottky Diodes can be successfully explained on the basis of TE mechanism with a Gaussian distribution of the BHs. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2790

Preparation, Characterization and NO-CO Redox Reaction Studies over Palladium and Rhodium Oxides Supported on Manganese Dioxide

The catalytic activity of PdO/MnO2 and Rh2O3/MnO2 is investigated for NO-CO redox reaction. Supported catalysts are prepared by wet impregnation method. Among the tested catalysts, PdO/MnO2 shows higher activity for this reaction. Active metal dispersion on MnO2 enhances the selectivity for N2 over N2O in this reaction. The XRD substantiate the formation of MnO2 monophasic phase. SEM images show the formation of elongated particles. TEM images indicate nano-size rod-like morphologies. An increase in the catalytic activity is observed on supported Pd and Rh oxides on MnO2. Temperature programed desorption studies with NO and CO are undertaken to investigate the catalytic surface studies. © 2015 BCREC UNDIP. All rights reserve

Productivity enhancement by reducing adjustment time and setup change

The paper presents a study of set-up time reduction in a small factory involved in the machining of precision components in small batches with large variety for the automobile industry. The factory has made some set-up reductions mainly using work study related methods and in one manufacturing cell by the use of the Single Minute Exchange of Die (SMED) methodology. Until recently the set-up times were not measured and worse still were considered as productive hours. As a consequence, there was a lack of awareness and motivation amongst operational personnel to reduce set-up times and knowledge of SMED was limited to a small group of individuals. This, along with the lack of investment in mechanisms to aid set-up time reductions and prevent errors, has restricted the use of this type of methods and technology. However, there is evidence that the demands made by the factory’s major customer will lead to increased efforts to put into place these types of changes

Simulation of CIGS thin film solar cells using AMPS-1D

The solar cell structure based on copper indium gallium diselenide (CIGS) as the absorber layer, cadmium sulfide (CdS) as a buffer layer un-doped (i) and Aluminium (Al) doped zinc oxide (ZnO) as a window layer was simulated using the one dimensional simulation program called analysis of microelectronic and photonic structures (AMPS-1D). In the simulation, the thickness of CIGS layer was varied from 300 to 3000 nm. The rest of layer’s thicknesses were kept constant, viz. 60 nm for CdS, and 80 nm and 500 nm for i- and Al-ZnO, respectively. By varying thickness of CIGS layer the simulated device performance was demonstrate in the form of current-voltage (I-V) characteristics and quantum efficiency (QE). When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2209

Laser Induced Damage Studies on Al2O3, SiO2, and MgF2 Thin Films for Anti-Reflection Coating Application in High Power Laser Diode

The laser diode facet damage is one of the impeding factors of the high-power laser diode operation. To overcome this restriction laser diode facet coating can be utilized. During the high power operation of the laser diode, it is observed that the single layer anti reflection (AR) coating at the front facet shows optical damage while the multilayer high reflective coating at the back facet remains undamaged. To determine the “damage threshold” of the materials used for AR coating, an e-beam evaporated Al2O3, MgF2, and SiO2 single layer thin films on GaAs substrate have been optimized for the wavelength ~ 1060 nm. The diode pumped Q-switched Neodymium Yttrium Aluminum Garnet (Nd:YAG) laser (1064 nm) was used to da-mage the samples. The damage on the sample was observed under the microscope. The effective damage radius on the samples was 150 m and average continuous wave laser induced damage threshold was found 10 W. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3101

Magnetron sputtered Al-ZnO Thin films for photovoltaic applications

The optimization process of the RF magnetron sputtered Al - doped ZnO (AZO) thin films was carried out by studying its structural, optical, electrical, and morphological properties at different RF power and different working pressures for its use as a front-contact for the copper indium diselenide (CIS) based thin film solar cell. The structural study suggests that the preferred orientation of grains along the ( 002) plane having a hexagonal structure of the grains. The optical and electrical properties suggest that the films show an average transmission of 85 % and a resistivity of the order of 10-4 Wcm. The morphology analysis suggests the formation of packed grains having a homogeneous surface. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2210

The optimization of optical thin films deposition using in-situ reflectivity measurements and simulation

We have optimized and automated the experimental in-situ reflectivity measurement system for the laser diode (LD) facet coating. We have also developed a reflectivitysimulator program that gives the reflectivity data as a function of the thickness of the film (single or multi-layer) for a given wavelength, which aids in optimizing the above parameters while monitoring the coating of the films in-situ. We report the results for the in-situ reflectivity of a single layer MgF2 and a quarter-wave optical thick three bi-layer pairs of MgF2 and silicon on GaAs as a substrate for both the cases. We have achieved up to 83 % experimental reflectivity for the latter case. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2207

Molybdenum back-contact optimization for CIGS thin film solar cell

Molybdenum (Mo) thin films are most widely used as an ohmic back-contact in the copper indium diselenide (CIS) and its alloy copper indium gallium diselenide (CIGS) based thin film solar cell. Radio frequency (RF) magnetron sputtering system used to deposit Mo thin films on soda lime glass substrate. The deposition was carried out using argon (Ar) gas at different Ar controlled (working) pressures (1 mTorr to 10 mTorr) and at different RF powers (60 W to 100 W). The influence of both the working pressure and the RF power on the Mo thin films was studied by investigating its structural, morphological, electrical, and optical measurements. The results reveal that a stress-free, low-sheet-resistance (~1 W/), and reflecting (~ 55 %) Mo thin film was observed at 1 mTorr working pressure and 100 W RF power. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2211

Laser scribing optimization of RF magnetron sputtered molybdenum thin films

The optimization process of laser scribing of back contacts is carried out by varying different parameters of laser and thickness of Molybdenum (Mo) thin-films. Mo thin films were deposited by RF magnetron sputtering on the organically cleaned soda lime glass substrate. The thickness of Mo was in the range of 60 nm to 800 nm. For the scribing process the laser power and the laser pulse frequency were varied. Different thickness of Mo shows the different scribe behavior. The optimized process provides a successful isolative laser scribing, having a minimum scribe line width, of Mo layer on glass substrate without any presence of walls, ridges, or collars in scribed areas. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/929