الفهرس 
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Abstract
Semiconductor materials as Copper Indium Diselenide (CuInSe2) thin film nanostructure was involved in featuring junction structures which entered in many electrical devices [1]. It was prepared using electrochemical potentiostatic deposition technique (one step) using electrolytic solution Copper sulfate (CuSO4 = 3 M),Indium sulfate (In2 (SO4)3 = 3 M),Selenium dioxide (SeO2 = 2.5 M, 3.75 M and 5 M)
and Citric acid (C6H8O7 = 100 M). In addition, H2SO4 was used to adjust the pH value at 2.14, deposition potential -500 and -600 mV (SCE) and deposition temperature (25 and 40 °C) for (1,1.5& 2 hr) are used for optimizing the properties of CuInSe2 thin films. The preferable parameters for high-quality and homogeneity of CuInSe2 thin films fabrication were deposition time = 1.5 hr and SeO2 concentration = 3.75 M. CIS
was deposited on sputtered Mo thin film as a back contact for the junction on glass substrate. High concentration of citric acid (100 M) was used in the bath solution for preparing CIS thin films. They were characterized using X-ray diffraction (XRD),effect of deposition (time, potential and temperature) and SeO2 concentration on CIS thin film formation, energy dispersive X-Ray analysis (EDX), Fourier transform infrared spectrophotometer (FTIR), Raman micro-spectroscopy analysis and scanning electron microscopy measurements (SEM).The ternary compound (I-III-VI2)
semiconductor CuInSe2 (CIS) has become one of the leading materials for large scale applications. It has a direct band gap, high absorption coefficient ( >105cm-1) [2].Broadened diffraction peaks of the chalcopyrite phase CuInSe2 thin film prepared at deposition temperature of 25 ºC and applied potential of -500 mV (SCE) for 1.5 hr are detected in the XRD spectrum, while its crystallinity was enhanced after the heat treatment process.On the other hand, it is directly formed at a deposition temperature
40ºC and an applied potential -600 mV for 1.5 hr, XRD spectrum, showing new
planes of CIS after the heat treatment process ,{chalcopyrite CIS (112) plane,second binary phase of CuInSe2 film is formed with (In2Se3) at higher various intensity ranges}. The best result in EDX analysis after the heat treatment at 450C are (Cu/In
=1.007) at (SeO2 concentration = 3.75 M, t = 1.5 hr, T= 25 ºC and V= -500 m
(SCE)) and (Cu/In = 1) at (SeO2 concentration = 3.75 M, t =1.5 hr, T = 40 ºC and V= -600mV (SCE)). We noticed an improvement in the absorbance peak of CIS after heat treatment at 450 C at range 2345.28 cm-1 at { T, V are T = 25 ºC and V= -500 mV (SCE) for 1.5 hr }to 2857.67 cm-1, corresponding to (Cu – Se2 – In) by applying FTIR test at {T, V are T = 40 ºC and V= -600 mV (SCE) for 1.5 hr }. After heat treatment at
450 C the Raman spectra of CIS is appeared at peaks of-CIS,-CIS and -CIS a
172 cm-1, 340 cm-1 and 192 cm-1 for { T = 25 oC and V= -500 mV for 1.5 hr } and it is detected -CIS and -CIS at 340 cm-1 and 192 cm-1 , in addition a peak at 280 cm-1 identifying CuxSe and a peak of -In2Se3 at 125 cm-1 for { T = 40 oC and V= - 600 mV for 1.5 hr } is registered. As a result of changing the deposition conditions, we obtained increasing the layer thickness of CIS from 0.788 μm which is closed to the
theoretical thickness of CIS film {d= 0.7986 μm at T = 25 oC, V= - 500 mV, t = 1.5 hr and SeO2 concentration = 3.75 M} to 1.014 μm after heat treatment at 450 C. On the other hand, the particle size of CIS is increased from 32 to 82 nm. But we noticed a decrease in the layer thickness of CIS from 5.12 μm , which is a large value compared with its theoretical value in which thickness of CIS film is reached to {d=
0.952 μm at T = 40 oC, V= - 600 mV, t = 1.5 hr and SeO2 concentration = 3.75 M}
to 1.979 μm after heat treatment at 450 C. On the other hand, particle size of CIS decreased from 41 to 25 nm. The condition for electro-deposition of chalcopyrite structure CIS thin film is heat treated at 450 oC to obtain CIS thickness which is increased from 1.014 μm at ( T = 25 oC ,V= -500 mV, t = 1.5 hr& SeO2 concentration = 3.75 M) to 1.979 μm at ( T = 40 oC ,V= -600 mV, t = 1.5 hr& SeO2 concentration = 3.75 M), and consequently decreasing particle size of CIS is decreased from 32 nm to 25 nm to improve and expand the use of CIS thin film in many electronic applications such as diode. We prepared a diode from heterstructure Junction within layers semiconductors and it is consists of Glass/Mo/CIS/CdS/ITO. from study the current-voltage characteristics we indicted the best behavior of dark diode junction of Glass/Mo/CIS/CdS/ITO with series resistance (19 Ω) which is corresponding to ideality factor n extracted (1.16 ) at { T = 40 oC and V= - 600 7mV(SCE) for 1.5 hr }