Materials Science and Engineering B-advanced Functional Solid-state Materials, 2006
InP thin films were prepared on glass substrates by the spray pyrolysis technique. Results on str... more InP thin films were prepared on glass substrates by the spray pyrolysis technique. Results on structural, optical and electrical properties of the layers as a function of the thermal annealing are reported. XRD data indicates that samples show microstructural perfection improvement as a function of annealing time. The optical band-gap shows a dependence with the inverse of the squared crystallite size, suggesting that electron confinement has some effect. The lattice parameter and band-gap energy (BGE) of the samples annealed at 450 °C for 160 min (20–40–80–120–160–200) correspond to the reported values of InP thin films. In addition, the electrical resistivity measurement shows a slight decrease when annealing time is increased up to 80 min but it saturates annealing times between 80 and 160 min. Then it is slightly increased for larger times.
In this work, the effect of pre-irradiation heat treatment on the TL glow curves (GCs) of ZnS thi... more In this work, the effect of pre-irradiation heat treatment on the TL glow curves (GCs) of ZnS thin films which were deposited onto glass substrate by spray pyrolysis method using mixed aqueous solutions of ZnCl2 and thiourea was investigated. It was observed that in spite of significant effects of pre-irradition heat treatments on the number of trap states and intensity of TL GCs, there is no considerable effect of it on the trap parameters of glow peaks of developed ZnS thin film. The TL data obtained from the recorded GCs indicates an impurity influence on both the deep and shallow traps with heat treatment. TL results have been then discussed on the basis of a restructuring of the defect concentration resulting from alterations in the surface properties of the thin films and diffusion of impurities (chlorine and oxygen) induced by annealing.
ZnSe thin films have been deposited on high cleaned glass substrate by spray pyrolysis technique ... more ZnSe thin films have been deposited on high cleaned glass substrate by spray pyrolysis technique within the glass substrate temperature range (400 ○C to 450 ○C). The structural properties of ZnSe thin films have been investigated by (XRD) X-ray diffraction techniques. The X-ray diffraction spectra showed that ZnSe thin films are polycrystalline and have a cubic (zinc blende) structure. The most preferential orientation is along the (111) direction for all spray deposited ZnSe films together with orientations in the (220) and (311) planes also being abundant. The film thickness was determined by an interferometric method. The lattice parameter, grain size, microstrain and dislocation densities were calculated and correlated with the substrate temperature (TS). The optical properties of ZnSe thin films have been investigated by UV/VIS spectrometer and the direct band gap values were found to be in the region of 2.65 eV to 2.70 eV. The electrical properties of ZnSe thin films have been investigated using the Van der Pauw method and the high quality ZnSe thin films were observed to develop at 430 ○C with a resistivity of 56,4×105 ohm cm, a conductivity of 1.77×10-7 (Ω cm)-1 and a hall mobility of 0.53 cm2/Vsec.
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2006
InP thin films were prepared on glass substrates by the spray pyrolysis technique. Results on str... more InP thin films were prepared on glass substrates by the spray pyrolysis technique. Results on structural, optical and electrical properties of the layers as a function of the thermal annealing are reported. XRD data indicates that samples show microstructural perfection improvement as a function of annealing time. The optical band-gap shows a dependence with the inverse of the squared crystallite size, suggesting that electron confinement has some effect. The lattice parameter and band-gap energy (BGE) of the samples annealed at 450 °C for 160 min (20–40–80–120–160–200) correspond to the reported values of InP thin films. In addition, the electrical resistivity measurement shows a slight decrease when annealing time is increased up to 80 min but it saturates annealing times between 80 and 160 min. Then it is slightly increased for larger times.
In this work, the effect of pre-irradiation heat treatment on the TL glow curves (GCs) of ZnS thi... more In this work, the effect of pre-irradiation heat treatment on the TL glow curves (GCs) of ZnS thin films which were deposited onto glass substrate by spray pyrolysis method using mixed aqueous solutions of ZnCl2 and thiourea was investigated. It was observed that in spite of significant effects of pre-irradition heat treatments on the number of trap states and intensity of TL GCs, there is no considerable effect of it on the trap parameters of glow peaks of developed ZnS thin film. The TL data obtained from the recorded GCs indicates an impurity influence on both the deep and shallow traps with heat treatment. TL results have been then discussed on the basis of a restructuring of the defect concentration resulting from alterations in the surface properties of the thin films and diffusion of impurities (chlorine and oxygen) induced by annealing.
ZnSe thin films have been deposited on high cleaned glass substrate by spray pyrolysis technique ... more ZnSe thin films have been deposited on high cleaned glass substrate by spray pyrolysis technique within the glass substrate temperature range (400 ○C to 450 ○C). The structural properties of ZnSe thin films have been investigated by (XRD) X-ray diffraction techniques. The X-ray diffraction spectra showed that ZnSe thin films are polycrystalline and have a cubic (zinc blende) structure. The most preferential orientation is along the (111) direction for all spray deposited ZnSe films together with orientations in the (220) and (311) planes also being abundant. The film thickness was determined by an interferometric method. The lattice parameter, grain size, microstrain and dislocation densities were calculated and correlated with the substrate temperature (TS). The optical properties of ZnSe thin films have been investigated by UV/VIS spectrometer and the direct band gap values were found to be in the region of 2.65 eV to 2.70 eV. The electrical properties of ZnSe thin films have been investigated using the Van der Pauw method and the high quality ZnSe thin films were observed to develop at 430 ○C with a resistivity of 56,4×105 ohm cm, a conductivity of 1.77×10-7 (Ω cm)-1 and a hall mobility of 0.53 cm2/Vsec.
Uploads
Papers by mustafa oztas