SnS thin films were electrodeposited onto ITO-coated glass substrates using one-step potentiostatic electrodeposition in a bath solution consisting of tin chloride (SnCl2) and sodium thiosulfate (Na2S2O3) for different concentrations of triethanolamine complexing agent (TEA). For the kinetic study, the charge transfer coefficient αc, the diffusion coefficient D, and the potential dependent cathodic rate kc were deduced by analyzing cyclic voltammograms and potentiostatic current transients. The electrochemical study showed that the charge transfer controls the electrodeposition of SnS in the presence of TEA. The effect of triethanolamine addition on the structural, morphological, compositional, and optical properties was studied using XRD, SEM, EDX, Raman, and UV–visible techniques. FV All samples crystallize in the orthorhombic SnS phase. It was found that the addition of TEA not only affects the surface morphology of the films by reducing the grain size, but also slows down the deposition of tin and thus improves the stoichiometry of the film. The vibrational modes of the tin chalcogenides SnS, SnS2, and Sn2S3 helped in the identification of the sample’s chemical structure. All samples displayed low transmittance in the visible range, which decreases with the increase of the agent concentration. The band gap was identified to be direct and increases with TEA in correlation with structural parameters. The optimal properties and the stoichiometry were reached for the concentration ratio [Sn:S:TEA] = [1:4:1] and were found in good agreement with the calculated electrochemical parameters.

Polycrystalline Cd1-xZnxTe thin films are prepared on glass substrates by a Hot-Wall Evaporation technique with different compositions. Optical transmittance and interference fringes are used to investigate optical properties in 320-3500 nm wavelength range at room temperature. As results, high transmittance in higher wavelength region, sharp absorption edge, direct optical transition and homogeneous deposition are highlighted. Refractive index exhibits normal dispersion following Sell Meier formula as well. In addition, electronic structure calculations based on FPLO method are performed and computed energy gap is compared to experimental data.

A higher quality and a nearly stoichiometric composition of Cd0.5Zn0.5Te have been successfuly grown on glass substrate by vacuum evaporation technique. The composition and structural studies are investigated by energy dispersive X-ray analysis, SEM, and X-Ray diffraction. Film optical constants are determined from transmittance measurments at normal light incidence in the spectral range (500-2500 nm). The presence of interference fringes and of a sharp absorption edge are indicatives of a very good optical quality. Analysis of the refractive index n(lambda), of the induced absorption alpha (h nu) and the determination of the energy bandgap Eg, are then given from the aquisition of the transmission data. Comparaison with previous works on films prepared by other techniques confirms a better quality of our films prepared at low cost.

First-principles calculations of the ground-state properties and the stability of Cd1-xZnxTe solid solutions are presented using the full-potential linearized augmented plane wave (FP-LAPW) method in combination with the local density approximation (LDA). It is found that the structural parameters, i.e. lattice constants and bulk moduli follow a linear function of the composition x. The stability of the alloys is viewed as an energetic balance between pure structural constraints and quantum chemical effect. Our calculations yield to the prediction of an ordering tendency for low Zn content, occurrence of an intermediate disordered phase at 50-50 % of composition and phase separation for the Znrich range. These results agree well with the recent experimental work by Arbaoui et al. Sol. Ene. Mater. Sol.-Cells. 2006. 90. P. 1364.

Polycrystalline thin films of the alloy Cd1−xZnxTe deposited by RF magnetron sputtering technique on corning glass substrate and subsequently annealed in vacuum, were found to be very homogeneous, nearly stoichiometric and single phase but only at low zinc content (x<0.4). We will present the effect of Zn composition and post deposition annealing on the alloy formation. It is found that a weak concentration in Zn is more favourable to the formation of the ternary Cd1−xZnxTe. Samples with high Zn contents are found to be more oxidized and impoverished on tellurium after annealing. Correlation with the results obtained from calculations of phase diagram using an associated solution model is carried out.

Qualitative study of the influence of parameters used for the fabrication of porous silicon (i.e. anodic current (I), concentration relationship HF/ethanol (C), anodization time (t)) on the physical properties of the porous layers such as porosity and thickness, has been performed using the experiment charts method.

Investigating the growth conditions, as well as the electrical and optical properties, of ZnSiAs2 layers grown on semi-insulating GaAs substrates by atmospheric pressure metalorganic vapor phase epitaxy, we have found the following: (i) successful growth conditions correspond only to a very narrow temperature range (650–680°C) and a “hot wall” technique has been found necessary; (ii) X-ray diffraction analysis demonstrate epitaxial growth with the c-axis perpendicular to the interface; (iii) most hetero-epitaxial layers have a mirror-like surface and good optical properties; (iv) differential reflectivity at 2 K reveals fine structures associated with folded electronic states of the topmost valence band and the lowest conduction band; (v) all layers are p-type and the high carrier concentrations (1018 to 1019 cm-3) indicate finite contamination effects or autodoping phenomena.

Des dépôts de Ge dopés As sont obtenus par transport en phase vapeur par la réaction de disproportionnation : 2 GeI2 = Ge + GeI4.Ils sont de type n et leurs caractéristiques électriques : p, 03BCH, n sont étudiés en fonction de la température de substrat et du débit de AsH3.L'incorporation de As dans la couche est étudiée thermodynamiquement.Abstract.-As doped Ge layers were obtained by chemical vapour transport using a disproportiounation reaction 2 GeI2 = Ge + GeI4.They were n type and their electric parameters p, 03BCH, n were studied as a function of substrate temperature and flow rate of AsH3.The incorporation of As into the epilayer is studied thermodynamically.

Epitaxial layers of germanium have been grown from the vapor phase on (100) oriented gallium arsenide substrates. n- and p-doped Ge were obtained by incorporation of As and B. The growth rate of single crystal heterojunctions is investigated by varying their basic growth parameters such as substrate temperature, pressure and gas flow rate of dopant species.

B doped Ge layers were obtained by chemical vapor transport using a disproportionation reaction 2GeI2=Ge+GeI4. They were p-type and their electric parameters: resistivity ϱ, Hall mobility μH and carrier concentration p were studied as a function of substrate temperature, partial pressure of BI3 and hydrogen flow rate on BI3 source. The incorporation of B into monocrystalline layers is studied thermodynamically.

Des couches épitaxiées de germanium dopé n et p ont été obtenues sur substrat de germanium par transport en phase vapeur en tube ouvert utilisant la décomposition de GeI2. Le dopage n et p est obtenu par incorporation d'arsenic et de bore. La croissance a lieu dans un intervalle de température de 320–380°C, pour une vitesse de croissance de l'ordre de 0,2-1,4 μm h−1. L'épitaxie est fonction de fonction de la température de substrat, de la pression et du flux des espèces dopantes.