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Cadmium Selenide (CdSe and CdSe:Ga) alloy has been prepared successfully in an evacuated quartz tube at a pressure (10−2 Torr). The structure of the CdSe alloy (powder) was tested by X-ray diffraction (XRD) and found as a polycrystalline (hexagonal) structure. CdSe and CdSe: Thin films have been deposited with a thermal evaporation process on the glass and Si substrates. The aim of this kind of study was to determine the ultrastructural morphology and optical properties of pure CdSe and Ga doped films produced using a method of thermal evaporation. The effect of Gallium on the structural and optical properties of CdSe thin film were doped at 0, 1, 3 and 5%. For all Ga doping ratios, the structural features such as the size of the grain and the micro strain of the thin film have been clarified with XRD technique and XRD pattern. The chosen orientation (002) for all prepared film has been polycrystal structures (hexagonals). With an increase in Ga from 37,54 to 21,37 nm, the grain volume decreases. AFM and SEM were used to study the morphology and surface roughness of the CdSe pure and doping films. All films were homogeneous with a characteristic spherical grain size depending on Ga concentration. The roughness of the films increases with the increase of Ga dopant. UV-Visible spectra photometer is used to investigate the visible properties such as absorption, absorption coefficient and energy gaps in thin films. The absorption value subsequently increased with Al doping concentration of localized states in the band gap of the films increases with the increasing of Al dopant, where optical energy gap values decreased with increasing the proportion of the doping in the range between 1.74 and 1.62. The grain size for pure and Ga- doped CdSe of thin films were decreased with Ga ratios. The absorption coefficient determined depends on photon energy incident (hv), the energy gap of the semiconductor as well as the form of transitions. In conclusions, CdSe and CdSe:Ga were successfully prepared from pure elements Cd, Se and Ga. XRD patterns showed the CdSe and CdSe:Ga films are polycrystalline of hexagonal structure directions by Ga doping that orientated a peak became less intensity from undoped CdSe film. The XRD patterns and AFM measurements of Ga-doped and undoped CdSe thin films agree with each other of the grain size within nanocrystal range and decrease as Ga doping concentration increases. AFM images indicate that the increasing in Ga doping that showed smooth surface films compared to the CdSe films. The optical bands gaps of the films have a direct band transition and slightly decreased with the increasing Ga doping.

Heterojunctions n-CdSe/p-Si, n-CdSe/P-Si and CdSe:Ga/p-Si have, through thermal evaporation, been based on P-type Si (002). Thin films with different doping ratios of 1, 3 and 5 wt percent are made. For the purpose of achieving optimal conditions the electrical and photovoltaic aspects of these films have been established. Solar cell quality is graduated. They were made of a vacuum heat evaporated mixture of CdSe and ga atoms to create a thin, p-Si single wafer film with a thickness of 3.5 μm and resistivity of 0.78-1.5 Ohm-cm-2 on R.T. They are then formed by n-CdSe/p-Si and n-Cdse(Ga)/p-Si heterojunctions. The density of the existing short circuit (jsc, open-circuit (Voc/fill factor (ff)) and conversion rate of 40 mW/cm2 (AM1) intensity. The efficiency of solar cells is calculated prior to and after a Ga dopant. The aim of this analysis was to determine characterization and optoelectronic characteristics of CdSe pure and gallium-doped solar cells in thin films. The result of this analysis under dark I-V conditions show good disciplinary behavior and an exponential relationship to the potential present bias. The calculation of the C-V suggested an abrupt form of heterozone diodes. The built-in potential Vbi is calculated and is found increasing after Ga-doping process. The built-in potential and the depletion width increases with increasing of Ga doping ratio. Solar cell conversion efficiency of n-CdSe/p-Si and n-CdSe:Ga/p-Si heterojunction properties were studied is found to be 5.25 % at 5 Wt% of Ga doping ratio. In conclusions, The I-V characteristic of Ga-doped CdSe solar cell thin film under the illumination conditions gives conversion efficiency of 5.25% at doping ratio 5%. This result of conversion is directly proportional to the Ga concentrations.

Purpose: The purpose of this paper is to investigate about time management effect on the relationship between knowledge management and organization performance. Design/methodology/approach: The paper contains a comparative analysis of relevant literature from the fields of knowledge management, time management and organization