| As a kind of organic semiconductor, metallophthalocyanines(MPc) has been widely applied in many fields such as photoconductor, electroluminescences devices, non-linear optics devices, gas sensors, and solar cells, etc. The band structures of MPcs can feasibly be changed on purpose by kinds of methods. This key characteristic makes it possible to enhance the photoconductivity properties, and to adjust the spectral response range of devices made by MPc, which leads a bright future for application of phthalocyanines in opto-electronic field.In this thesis, two methods are discussed to enhance the opto-electronic properties of the MPc films. One is to improve the photoconductivity by annealing the MPc film under magnetic field; the other is to form composite multi-layer film of ZnO/PbPc and SnO/PbPc, to change the spectral response range of MPc films.Vanadyl phthalocyanine (VOPc) films prepared by vacuum deposition were annealed under magnetic field. UV-Visible absorption results showed that the films annealed under magnetic field showed a Q-band red-shift. X-ray diffraction study (XPJ)) indicated enhancement in diffraction intensity and shift of peak position. Further more, atomic force microscopy (AFM) results showed no noticeable difference in grain size. It's concluded that magnetic treatments results in oriented stacking of VOPc molecules. This change in crystal structure leads to an improvement in photoconductivity behavior: a photoreceptor used PbPc as the charge generation layer had a much shorter decay time.Composite films of ZnO/PbPc and SnO/PbPc were deposit separately. There were both obvious Q-band shifts in the absorption spectrum, while no variations in crystal structure showed in XRD results. It is thought that there are two type of interaction between the inorganic molecule and the phthalocyanine molecule: a) quantum confinement and b) charge transfer. These interactions varies the band structure of phthalocyanine, accordingly change the absorption spectrum of MPc films.
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