The effect of plasma irradiation is studied systematically on a 4H polytype (002) oriented ${\rm CdI_2}$ stoichiometric film having compressive residual stress. Plasma was found to change the orientation (110) at certain moderate distances. A linear decrease in grain size and stress observed with decreasing distance (or increasing ion energy) consistent both structural morphological observations. direct optical energy gap E_g}$ increase linearly rate 15\mu eV/atm}$ combined data present from...

The optical and transport properties of naturally occurring mineral pyrite (FeS2) are measured with a view to determine Eg, the energy gap this semiconductor scattering mechanism in low temperature region (80 270 K). Analysis absorption studies indicate be an indirect band which single phonon makes important contribution assisting transition. Conductivity Hall effect data intrinsic range yield value 0.92 eV at room for gap, close agreement obtained by studies. analysis conductivity all...

The amorphous-to-crystalline phase change induced by a continuous-wave laser was investigated systematically in the case of as-grown amorphous films , and results were compared. photo-thermal process is found to be responsible for all three compounds. minimum threshold power required induce optical contrast at an irradiated site depend on film thickness; however, density order films. All exhibited good potential use as WORM kind storage devices, having power. non-stoichiometric reversible storage.

The Sb2S3 films subjected to instantaneous heat treatment at various temperatures in air for a short duration of few seconds show systematic phase modification from an amorphous crystalline state. Structural and morphological analyses transformation around 162 °C consistent with the DTA result. compositional analysis (ESCA) shows increasing loss sulphur content film as function temperatures. optical properties reveal changing constants energy gap observed degree contrast heat-treatment...

The optical absorption near the fundamental edge was measured as a function of film thickness, substrate temperature, and heat treatment temperature for hexagonally structured (4H polytype) stoichiometric ${\mathrm{CdI}}_{2}$ films. structural analysis shows well oriented (hh0) parallel to plane with residual tensile stress in film. Residual found increase nonlinearly both thickness while it decreases linearly temperature. direct indirect types interband transitions agreement earlier...

This paper addresses issues of the subtle kinetic changes on superstructural phase formation in technologically important Sb/Si system. The thermal stability room-temperature (RT) deposited Sb a $(7\ifmmode\times\else\texttimes\fi{}7)$ reconstructed Si(111) surface by Auger electron spectroscopy (AES), low-energy diffraction (LEED), and energy-loss (EELS) is reported. At very low flux rate 0.03 ML/min uptake shows that it grows Frank--van der Merwe mode yielding...

Siemiconducting thin iron pyrite films are grown by thermal evaporation. The resistivity of the is measured in thickness range 10 to 150 nm. Other correlated experimental techniques like Hall effect and TCR used confirm semiconducting nature films. higher than 50 nm yield saturated value for resistivity. F-S theory estimate mean free path carriers. Dünne halbleitende Eisenpyritschichten werden mittels thermischer Aufdampfung hergestellt. Der Widerstand der Schichten wird im Dickenbereich bis...

A systematic optical absorption study near the fundamental edge was carried out on both amorphous and polycrystalline films of Stibnite in temperature range 90-320 K. Films were grown using naturally occurring single crystals Stibnite. The band gap thermally evaporated which have stoichiometry Sb 43 S 57 determined to be direct dependant. phase at any is considerably less than that crystalline ones. dependence cases agrees well with Varshni formula. 0 K for by fitting experimental data...

The aim of this study was to investigate the morphology and optical absorption PbI 2 thin films. films different thickness were deposited on glass substrate at ambient temperature by thermal evaporation technique. deposition rate optimized 1-2 nm/s grow uniform good quality structural analysis carried out X-ray diffraction (XRD). so prepared studied Scanning Electron Microscope (SEM). spectra recorded using a UV-Vis fiber optics based spectrophotometer. All measurements in present work room...

First-principles calculations are carried out to investigate the effect of pressure (up 40 GPa) on electronic, optical and elastic properties scintillator material calcium iodide, CaI2, by using Perdew–Burke–Ernzerh generalized gradient approximation (PBE-GGA). The electronic band structure reveals an indirect gap 3.89 eV a direct 4.35 for zero pressure. We have also calculated dependence properties. constants moduli increase nonlinearly with Decreasing Pugh’s ratio increasing hardness...

The thermally evaporated layer structured BaI2 grows in various completely preferred (hkl) film orientations with different growth parameters like thickness, deposition rate, substrate temperature, etc. which were characterized by structural, morphological, and optical absorption measurements. Structural analysis reveals the strain films shows a direct type band gap. varying gaps of these found to scale linearly their strain. elastic moduli other constants also calculated using Density...

The optical-absorption measurements are reported for ${\mathrm{ZnI}}_{2}$ films. optical band gap of stoichiometric, tetragonally structured films found to be direct type. thickness dependence is attributed the compressive residual stress in film. variation with film correlates well packing density and size distribution crystallite grains as observed by morphological analysis. Band was decrease linearly yielding a 4.75 eV stress-free perfect crystal. absorption data reveal an exitonic peak...

The optical properties of vacuum-evaporated, stoichiometric, well-characterized ${\mathrm{PbI}}_{2}$ films exhibit quantum-dot-like behavior and strain dependence. shifts in peaks obey a linear with the determined by x-ray diffraction. energy shift due to residual stress can be separated from measured data obtain contribution only confinement effect. peak at around $3\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ shows systematic blueshift decrease grain size $D$. observed dependence on $1∕{D}^{2}$...

Detailed structural, electronic, optical and elastic properties with their pressure dependence of two barium halide scintillators are presented using first-principles calculations based on the density functional theory formalism. Only PBE-GGA results tally closest experimental a band gap 4.26 eV for BaBr2 4.96 BaCl2. The electron () hole effective masses determined to be 0.88 0.95 BaCl2 0.86 0.91 BaBr2. yields coefficient as −4.34 × 10−2 GPa−1 −3.77 BaCl2, respectively. All constants related...