Performance of Chemical Vapor Deposited ZnO thin film as thermal interface material on optical properties of LED

Chemical Vapor Deposition (CVD) was used for the synthesis of ZnO thin film on Al substrates at various flow rates of O2 gas. ZnO thin film coated substrates were tested as thermal substrates on influencing the optical properties of high power LED at various operating currents. Spectrometer analysis showed that ZnO thin film prepared at 10 sccm O2 flow rate showed better performance by reducing the Color Correlated Temperature (CCT) at driving currents. CCT values were maintained with respect to driving currents by ZnO thin film interface at all driving currents than air interface (bare Al substrate). On luminous flux analysis, 5 sccm samples showed good performance on increasing the light of the give LED at all driving currents than bare Al boundary condition. The observed results were evidenced with help of particle size distribution analysis on all film surface using Nanoscope software. Overall, ZnO thin film deposited at low O2 flow rate would be an alternative to solid thin film interface material in electronic packaging applications

Optical properties of amorphous ZnO thin film prepared from boiled Zn thin film in ultra high pure water

Amorphous zinc oxide (a-ZnO) thin films were synthesized from RF sputtered Zn thin films. The conversion was performed by processing Zn thin film in ultra high pure water at 95°C in various process times (120–180 min). X-ray spectra revealed the presence of amorphous ZnO in the processed films. The calculated band gap was laid in between 3.25 and 3.2 eV. Non-linear behavior in I-V characteristics was observed for all films. The structural defects of a-ZnO were confirmed with PL and Raman studies. The synthesized films at 180 min were more oxygen deficient

Synthesis and properties of 10% Zn layered CdTe thin films by SEL method

Te/Cd/Te/Zn/Cd stacked layers were prepared by Stacked Elemental Layer (SEL) Method. All stacks were annealed from 200 °C to 500 °C and the prepared films were confirmed as polycrystalline nature. Cubic CdTe and Hexagonal ZnTe were identified at high annealing temperature. Transmittance spectra emphasized the significance of Zn doping by annealing the stack. The calculated optical constants n and k were 1.52–2.45 and 0.07–0.36 respectively. The band gaps (Eg) were observed between 1.38 and 1.44 eV at above 350 °C. A uniform surface morphology could be observed at high annealing temperatures. The observed results encouraged the Zn doping using SEL method

Electrical and morphological analysis of oxygen plasma treated Zn metal thin films

RF sputtered Zn metal films were processed at O2 plasma at various process conditions. The surface morphology of the processed films was characterized using SEM and AFM techniques. Dense and continuous film surface with good surface morphology were observed in all plasma processed films. The microstructure of processed Zn films was very much dependent on the process parameters especially the plasma power and gas flow rate. The effect of these parameters on particle size and surface roughness was examined carefully. The particle size of all processed films lay in between 23 and 70 nm. Noticeable change on surface morphology, particle size and surface roughness was observed with respect to process parameters. The observed sheet resistance was an evidence of the influence of process parameters especially process time on the electrical properties of processed films. In addition, the influence of surface roughness and particle size on electrical resistance was also discussed

Structural, morphological and electrochemical characterization of electron beam deposited Li 1+x Mn 2 O 4 (x = 0, 0.05) thin films

Li 1+x Mn 2 O 4 (x = 0, 0.05) powders were synthesized using the microwave assisted co-precipitation method. Materials were evaporated using an electron beam gun. Structural analyses of thin films coated over platinum substrates revealed their cubic structure. The lattice constant of Li 1.05 Mn 2 O 4 thin film was found to be around 8.2475 Å. The lattice constant of Li 1.05 Mn 2 O 4 Powder was found to be 8.2488 Å. Morphological properties of the coated films were studied by SEM and the obtained micrographs were analyzed using the Image-j software. The roughness and the porosity were observed to be higher for the samples containing an excess of Li. The thin films were subjected to electrochemical characterization in aqueous LiNO 3 solution; cyclic voltammograms obtained for the samples revealed two sets of well defined redox peaks around 0.07 and 0.1 V in LiNO 3 solution. The redox peaks in Li 1.05 Mn 2 O 4 thin film samples had lower intensities than those of the stochiometric compound