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The critical exponents and magnetocaloric properties of La 0.7 Sr 0.3 Mn 1Àx Ti x O 3 with x = 0 and 0.05 have been explored via magnetic measurements. The magnetic data analyzed in the critical region by using modified Arrott plots, the... more
The growth of GaN and A1GaN by molecular beam epitaxy (MBE) has been studied using GaN/SiC substrates. The GaN/SiC substrates consisted of ~3 ~tm thick GaN buffer layers grown on 6H-SiC wafers by metalorganic vapor phase epitaxy (MOVPE)... more
Molecular beam epitaxy (MBE) of ZnO on both sapphire and SiC sub strates has been demonstrated. ZnO was used as a buffer layer for the epitaxial growth of GaN. ZnO is a wfirtzite crystal with a close lattice match (<2% mismatch) to GaN,... more
We report on the growth of Al 0.25 Ga 0.75 N/GaN heterostructures grown on low dislocation density vicinal surfaces of semi-insulating c-axis GaN substrates. Atomic force microscopy (AFM), photoluminescence (PL), cathodoluminescence (CL),... more
Delafossite CuAlO 2 p-type nanostructured semiconductor was synthesized using boehmite (-AlOOH) nanorods loaded with copper(I) acetate [Cu(OAc)] as a precursor (nanoprecursor). Because Cu(OAc)-loaded -AlOOH nanorods are highly... more
The design of van der Waals (vdWs) heterostructures are of novel great importance to boosting the efficiency of photovoltaic devices. Herein, we propose first-principles hybrid density functional theory calculations for a twodimensional... more
The design of van der Waals (vdWs) heterostructures are of novel great importance to boosting the efficiency of photovoltaic devices. Herein, we propose first-principles hybrid density functional theory calculations for a twodimensional... more
The interfacial charge density of regrown structures was studied for several different material systems: GaAs, InGaAs/InP, and InAlAs-InGaAs superlattice structures on InP. The particular application of interest is in the fabrication of... more
Tetrahedrite-based thermoelectric materials have received much attention in recent years due to their good thermoelectric performance and earth-abundance. The parent compound Cu 12 Sb 4 S 13 exhibits a high power factor and low lattice... more
We report calculations from first principles to determine the structural and electronic properties of ErB2 compound using the Density Functional Theory (DFT) and the Full-Potential Linearized Augmented Plane Waves (FP-LAPW) method. For... more
This paper proves the superiority and relevance of the modified wave theory of light and heat radiation as an improvement of the classical wave theory of light and heat radiation in answering questions on the photoelectric effect and... more
This paper proves the new modified wave theory of light and heat radiation as an improvement of the classical wave theory disproving the discrete quantum theory of light and heat radiation by max Planck and the photon theory of light by... more
X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) are commonly used to perform texture analysis of thin films. However, due to principle differences in data acquisition these techniques can yield disagreeing results. In... more
We have synthesized the intermetallic Tb 2 Fe 17 compound in hexagonal crystal structure by arc-melting without annealing. X-ray diffraction pattern has been refined by Rietveld method. The crystal structure is hexagonal with P 6 3 /mmc... more
In this paper, Si-doped GaN template layer and nitride-based multiple quantum well (MQW) light-emitting diodes (LEDs) with conventional GaN buffer layer and GaN buffer layer using SiN treatment were elaborated by metalorganic vapor phase... more
A technique for direct wafer bonding of III-V materials utilizing a dry sulfur passivation method is presented. Large-area bonding occurs for GaAs/GaAs and InP/InP at room temperature. Bulk fracture strength is achieved after annealing... more
Hydrazine derivatives are attractive low temperature nitrogen sources for use in MOVPE due to their low thermal stability. However their purification and subsequent analysis has not previously been investigated in depth for this... more
Hydrazine derivatives are attractive low temperature nitrogen sources for use in MOVPE due to their low thermal stability. However their purification and subsequent analysis has not previously been investigated in depth for this... more
Hybrid materials of conducting polymers with coordination compound dopants offer a desirable combination of properties for targeted applications. This work presents polythiophene/prussian red (PTH/PR) nanocomposites as hybrid materials... more
The spectral response of back-surface-illuminated p-GaN-i-GaN/AlGaN multiplequantum well (MQW)-n-AlGaN ultraviolet (UV) photodetector is reported. The structure was grown by molecular-beam epitaxy on a c-plane sapphire substrate. A MQW is... more
The effects of replacing the phenyl rings of triphenylamine (TPA) by naphtyl groups are analysed on a series of push-pull molecules containing a 2-thienyl-dicyanovinyl acceptor group. UV-Vis absorption spectroscopy and cyclic voltammetry... more
The rare earth orthoferrites RFeO 3 (R = Pr, Eu and Ho) were synthesized by the ceramic method. X-ray diffraction (XRD) was investigated to confirm the phase and orthorhombic structure with space group Pbnm. By varying rare earth ions,... more
Binary glass systems of the chemical composition 0.25Li 2 O-0.75B 2 O 3 and 0.25LiF-0.75B 2 O 3 with different additive ratios of V 2 O 5 were prepared using the melt-quenching method. Characterization was carried out through different... more
Various Hall Effects have been successfully observed in samples of n-type indium antimonide with values for conductivity, energy gap, Hall mobility and Hall coefficient all agreeing with theory. A particular interest in developing a... more
The search for stable and highly efficient solar cell absorbers has revealed interesting materials; however, the ideal solar cell absorber is yet to be discovered. This research aims to explore the potentials of dimethylammonium lead... more
The construction of a permeable thermoelement that uses heat fluxes carried by a gas or liquid is presented. A method for thermoelement design on the basis of mathematical optimal control theory and computer simulation techniques is... more
Effect of Yttrium on the Fracture Strength of the Sn-1.0Ag-0.5Cu Solder Joints
In this work, the two-dimensional (2D) numerical simulation of p-type poly-PbS TFT electrical characteristics are performed using a physically based device simulator Atlas/Silvaco. The analytical expressions of defect density models for... more
Ceramics based on magnesium titanate (MgTiO 3) are dielectric materials that have the potential to be used in telecommunications systems at microwave frequencies, such as filters, antennas, and signal generators. This study aims to... more
In this paper, the carrier density, temperature and quantum well width effect have been investigated for the optical gain for a Cd 1Àx Zn x Te/ZnTe Zinc-blend strained quantum well structure. The device emits laser radiations in... more
In this work, a ceramic composite of ZrW 2 O 8 and ZrO 2 was synthesized, in order to investigate the possibility of compensating the positive thermal expansion of ZrO 2 with the negative thermal expansion (NTE) compound ZrW 2 O 8 ,... more
One of critical problems faced by students in learning process is lack of teaching materials. Teaching materials are selected by the teacher, and mostly they focuson a review of materials and problem solving, without considering... more
The remarkable properties of carbon nanotubes (CNTs) make them attractive for microelectronic applications, especially for interconnects and nanoscale devices. In this paper, we report an efficient process to grow well-aligned CNT films... more
This study extends our previous work on liquid-phase deposition (LPD) of dense, high-quality, silicon-dioxide (SiO 2) films deposited on Si and GaAs substrates from supersaturated, hexafluorosilicic-acid aqueous at near room temperature.... more
Indium tin oxide (ITO) film was deposited on an ARTON plastic substrate using 80 W, direct current (DC) magnetron sputtering on an unheated substrate, then annealed at 150°C under either hydrogen or nitrogen gas for periods ranging from 2... more
Ion sensitive field effect transistor (ISFET) and membrane field effect transistor (MEMFET) have some drawbacks related to: long-term drift, hysteresis and thermal drift. These factors limit the accuracy of ISFET/MEMFET based measurements... more
In the present study, the effect of annealing and Ar-plasma treatment on structural, morphological and optical properties of thermally evaporated β-In2S3 thin films has been investigated. During Ar-plasma treatment, some interesting... more
Low temperature photoluminescence spectroscopy is used extensively to study the distribution of defects, concerning the type and impurity in a semiconductor film. Typical photoluminescence spectra are observed in a near band edge region.... more
Improved Cu2O/AZO Heterojunction by Inserting a Thin ZnO Interlayer Grown by Pulsed Laser Deposition
Cu 2 O/ZnO:Al (AZO) and Cu 2 O/ZnO/AZO heterojunctions have been deposited on glass substrates by a unique three-step pulsed laser deposition process. The structural, optical, and electrical properties of the oxide films were investigated... more
Microscopy and Microanalysis) facilities at IISc for providing the usage of FIB and TEM, respectively. Special acknowledgement to Mrs. Suma for teaching me FIB and always being there for all the help I needed. I am grateful to my... more
A new instrument is described for in-line monitoring of various process steps in silicon solar-cell fabrication. This system can rapidly measure a host of parameters that describe the front-surface and the back-surface properties of a... more
We have modeled diffusion of H in a two-step Si 3 N 4 passivation process invoking the concept of "storage" of H. The H stored during nitridation is redistributed during a subsequent anneal. The modeling results agree with this... more