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Thin films of Nanocrystalline Tin Oxide SnO2 and SnO2: Cu have been prepared on glass substrates using Chemical Bath Deposition (CBD) technique, The thickness of the deposited film was of the order of (300) nm . The films annealing in air at temperature 500◦C for 60 min .Structural, optical and sensing properties were studied under different preparation conditions like Cu-doping concentration (2%, 4% and 6%). These prepared films are polycrystalline with a tetragonal & orthorhombic crystal structure. The crystallinity and the particle size of the prepared samples were analyzed by X-ray diffraction (XRD), the results indicated the particle size of the prepared samples decreased with the increase of Cu doping concentrations some of the structure properties are changed by the addition Cu concentrations as dopants. The films are preferentially oriented along the (110) direction. We have got some surface morphology by Scanning Electron Microscopy (SEM), the results show decreasing of particle size with increasing doping concentration. The films have moderate optical transmission from (65% up to 88% at 800 nm), and the transmittance, absorption coefficient and energy gap were measured and calculated with Cu doping concentration. The results show that the doping caused to decreased the transmittance and energy gap from (3.55 to 3.8) eV while it caused to increase the absorption coefficient. It has also been found that Cu doped nanocrystalline SnO2 thin films gas sensing & recovery time material was presented a better sensitivity to CO gas compared to the pure SnO2.

In this work, preparation of high quality conductive oxide SnO2 thin film by post-thermal trearment of deposited tin by vacuum thermal evaporation on glass and p -type silicon substratesfor preparation of metal-insulator-semiconductor hetrojunction. The opticalabsorption, electrical, structural and surface morphology of the SnO2 thin film on glass substrate were characterized byUV-VIS-NIR spectrophotometer, electrical conductivity, X-ray diffraction spectrum andatomic force microscope respectively. The X-Ray Diffraction pattern show that the SnO2 thin film is polycrystalline with and tetragonal rutile, Atomic Force Microscope show that the grains size of the thin film varies from 50 to 150 nm .The optical properties show that SnO2 thin film is high absorbance in Ultra-violet region, whereas it's transparent in the visible and near infrared regions and have direct optical band gap of 3.6 eV, and last the electrical conductivity results show that the resistivity is decrease with increase the temperature and activation energy is approximately to the 0.107eV. The electrical properties of n SnO2/SiO2/p Sihetrojunctionwere studied by I–V measurement under dark and illumination conditions, in the dark condition, I–V measurement reveals that the heterojunction have rectifying behavior, the ideality factor and the reverse saturation current of this diode are 5.18 and 1.5×10–6 A respectively. Under illumination condition, I–V measurement reveals that the photocurrent is larger than the dark current, and a linear relation between ISC and VOC with the incident light intensity to reach a maximum value beyond tends to saturated and become constant. These electrical properties of prepared device can its work as a detector or solar cell.

In this work, studying the structural and optical Nano crystalline SnO2 thin films grown on cleaned glass substrates by using sol- gel (dip coating) technique. It is worthy to say that the thickness of the deposited film was of the order of (300-400)nm . The films are annealed in air at , 300◦C, 400◦C and 500◦C temperatures for 60 minutes. The films that are analyses by X-ray diffraction (XRD), Scanning electron microscopy (SEM) , atomic force microscopy and optical absorption spectroscopy technique. The size of crystalline was observed, as well as, so as to increase with increasing annealing temperature . XRD analysis reveals that the whole films are polycrystalline with tetragonal structure with preferred orientation of (110),(101),(200) and (211) . The increase of annealing temperature leads to raise the diffraction peaks and decrease of FWHM. The atomic force microscopy (AFM) and Scanning electron microscopy (SEM) results showed that the average grain size was increase with the increase in annealing temperature. Spectra of transmittance and absorbance was recorded at wavelengths range (300-1000)nm .The optical properties showed high transmission at visible regions. The optical band gap energy was found to be (3.5 , 3.75 , 3,87) eV at annealing temperature (300,400,500 )°C respectively.

In this research doped and undoped SnO2 was prepared by using cold wall atmospheric pressure chemical vapor deposition (APCVD) system at substrate temperature (450 0C) and flow rate of O2 gas (1.5) L/M for (15) min using (SnCl2.5H2O) and different percentage from (NH3F) , (SbCl3) as source for (Sn, F, Sb).Several films were prepared by using different ratios of antimony (Sn:Sb ) as fallowing: (1: 0.3, 1: 0.5, 1:0.7, 1:1 Wt. %)and (SnO2:F) in ratios of (1: 0.1, 1: 0.3, 1:0.5, Wt.%).X-ray diffraction (XRD) spectra showschanging in structures for (Sb, F) with shift in peaks.Also roughness average values have been increased with increase of doping ratio. Optical properties have been studied by using UV-Vis spectroscopy. Electric properties had been studied. through spectroscopic study of these films was found to have a high transmittance in the visible region.

Tin Oxide nanoparticles (SnO2-NPs) were prepared by mixing (SnCl4.5H2O) with distilled water at room temperature. The samples were characterized for their crystalline structure, morphology and chemical structure by using X-ray diffraction (XRD), Rietveld refinement, scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR). The XRD data and Dicvol 91 software analysis the crystal system was found to be tetragonal structure for samples prepared under stirring time for (24,48,72) h with (a=4.745 , c=3.184), (a=4.768 , c=3.255) and (a=4.776 and c=3.257) respectively. The average of crystallite size calculated by using SEM it was 9.45 nm, 14.7 nm and 21.5 nm, for the same times, previously mentioned of stirring. The effect of stirring time on the crystal lattice distortion ratio, specific surface area and dislocation density was discussed. The optical band gap values of SnO2-NPs were calculated to be about 3.4eV, 3.37eV and 3.2eV under stirring time for 24 h, 48 h and 72 h respectively by optical absorption measurement.

Transparent and conducting SnO2 thin film has been produced on (quartz and porous silicon) substrates using rapid photothermal oxidation of pure Sn in air at 600 oC oxidation temperature and different oxidation time. The structural properties and scan electron microscope of the prepared films were studied. The photovoltage properties of a Au/n-SnO2/p-PSi/c-Si solar cell are investigated under irradiation of Nd:YAG laser pulses. The porous Si layer is synthesized on a single crystalline p-type Si using electrochemical etching in aqueous hydrofluoric acid at a current density of 25 mA/cm2 for a 30-min etching time. The structure of the porous layer is investigated using scan electron microscope. The photovoltage properties are found to be dependent on the laser fluencies.

SnO2 nanoparticles were prepared by laser ablation of tin in methanol at room temperature. The particles were characterized by means of TEM, AFM, FTIR, UV-Visible absorption spectrum and electrical properties. AFM micrographs show that the obtained material is spherical nanoparticles, the size and size distribution of which depends on the experimental conditions. From FTIR spectrum show the peak absorption of SnO2NPssuspension at 657 cm-1. It is found that the band gap energy of SnO2NPs is higher than that of bulk SnO2 due to the decreases in the particle size according to the quantum confinement model. From the J-V characteristics Al/SnO2 NPs/c-Si/Al hetrojunction the values of ideality factor for these devices is greater than unity which can be attributed to the recombination of electrons and holes in the depletion region as well as the tunneling effect depending on both sides of the heterojunction and on the presence of defect states.

In this paper, the synthesis of nanostructure tin oxide SnO2 thin films on (0001) sapphire substrates using a pulsed 532 nm Nd: YAG laser is presented. Deposition of films is achieved at three different substrate temperatures 300,400,500ºC. The influence of substrate temperature on the structural and optical properties of tin oxide films are discussed and analyzed. We have shown the results of x-ray diffraction that all films prepared with the installation of multi crystalline (tetragonal) and directional prevalent (101) for all modds before and after annealing. These films are highly transparent (63–79%) in visible region, and transmittance of the films depends on substrate temperature. The band gap of the films varies from 3.45 eV to 3.61 eV for various temperatures. The morphology of deposited films was characterized by scanning electron microscope (SEM) and atomic force microscope (AFM), with increasing substrate temperature, both the grain size and surface roughness increase. We have also investigated the photoluminescence (PL) emission of the simples produced by PLD. The absorption of very intense PL emission for the films at temperature T= 500 ºC. The photoluminescence (PL) spectrum of the SnO2 exhibits visible light emission with a peak at 602 nm.

In this research SnO2 thin films have been prepared by using hot plate atmospheric pressure chemical vapor deposition (HPCVD) on glass and Si (n-type) substrates at various temperatures. Optical properties have been measured by UV-VIS spectrophotometer, maximum transmittance about (94%) at 400 0C. Structure properties have been studied by using X-ray diffraction (XRD) , its shows that all films have a crystalline structure in nature and by increasing growth temperature from(350-500) 0C diffraction peaks becomes sharper and grain size has been change. Atomic force microscopy (AFM) uses to analyze the morphology of the Tine Oxides surface structure. Roughness & Root mean square for different temperature have been investigated. The results show that both increase with substrate temperature increase this measurements deal with X-Ray diffraction results, that there is large change in the structure state of SnO2 thin f film by changing temperature parameter.

In this work, mixed oxide (TiO2-SnO2) thin films were grown on Si (111) and glass substrates by pulsed laser deposition (PLD) method. The influences of increasing amounts of SnO2 were investigated. The X-ray diffraction results show the peaks position of the plane was shifted towards higher angle values with increasing amounts of SnO2. The surface morphology of the deposits materials was also studied by using a scanning electron microscope(SEM) The results show that, the grain sizes decreases with increasing SnO2 content from the largest value (53.6)nm to smallest value (25.5) nm. From UV-visible spectroscopy, the distinct variations in the transmission spectra, and optical energy gap, of the thin films were also observed.

Nanostructured Tin oxide thin films were deposited on the Si (111) substrate using pulsed laser deposition technique at different substrate temperatures (200, 300,400 and 500 °C) in an oxygen pressure (5*10-1 mbar). The structure and morphology of the as-deposited films indicate that the film crystallinity and surface topography are influenced by the deposition temperature by changing from an almost amorphous to crystalline nanostructure and rougher topography at a higher substrate temperature. Hall Effect has been studied to estimate the type of carriers, from the result we deduced that the SnO2 thin films are n-type.

In this paper thin films of Tin oxide SnO2 was prepared by spray pyrolyess method on glass and pure silicon substrates at deposition temperature(300,400,500) Cᵒ, from Tin chloride at concentration(0.1 M) . The films thickness were about 0.1 ±0.02 μm and Atomization rate was about (1 nm/s). The test was done on prepared film by XRD and optical microscopy addition to sensitivity to nitrous oxide gas at different test temperature (25, 50, 75,100) Cᵒ. Result shows that the crystallization increased by increasing deposing temperature and the sensitivity increased by rising the gas concentration or temperature.

This work includes the deposition of SnO2 as a thin film on Si (111) by using the pulsed laser deposition method. The influences of oxygen pressure on the structural properties of Tin dioxide films were investigated. The X-ray diffraction results show that the structure of the films change from high polycrystalline to worse polycrystalline at an oxygen pressure of 10mbar. The surface morphology of the deposits materials was also studied by using a scanning electron microscope (SEM) and atomic force microscope (AFM). The results show that, the grain sizes of the nano particles observed at the surface depends on the oxygen pressure. As the pressure of the O2 gas increases the densities of the particles increases too. An oxygen pressure of 5×10-1 mbar was found the best pressure for the growth process. While the RMS roughness was seen to increase with increasing oxygen pressure. It was equal to (11.3 nm) for thin films deposited at (300)ºC.

In the present work, preparation of transparent conductive SnO2 thin films by classical-oxidation technique of thermal evaporated tin metal films, on glass substrates was carried out. The optical properties showed high transmission at visible and NIR regions. The energy band gap was found to be (3.82eV). The structure properties showed that the tin oxide peak appears at (2q =30.24) and (2ϴ=63.39°) . The atomic force microscopy (AFM) results showed a nano-structured for the thin film with particle size ranging (15-140)nm and its root mean square (RMS) value was found to be (5.72 nm ).

An investigation which include synthesis of SnO2 thin film by depositing onto glass substrates at room temperature using thermal evaporation technique. The films were post-annealing in furnace tube at 250 oC temperature for different time (10, 20, 30 and 40 minutes). The films were characterized by AFM microscopy, FTIR and optical absorption spectrophotometer. The grain size was observed to increase with increase the annealing duration. Absorbance spectra were taken to examine the optical properties and band gap energy was observed to decrease with increase the annealing duration. The effect of annealing time on the optical and morphological properties of films were studied and discussed