Optical Gain Material - Perylene Four Diethyl Imide Study,

Organic photoconductive materials have become one of the high-tech materials that are needed in the modern information society. Due to the rapid development of information technology, recently organic optoelectronic devices have attracted intensive interest amongscientists and technologists because of their huge market and intriguing potentialapplications. In this thesis, the photocurrent multiplication phenomenon in perylene dyes was investigated. In order to get strong π-interaction between two molecular plane and most superposition of molecular orbit, I selected symmetrically perylene pigments-N,N'-dimethyl-3,4,9,10-perylenetetracarboxylic diimide. The compound was synthesized through 3,4,9,10-perylenetetracarboxylic dianhydride and purified by nitrobenzene. The pure of product was identified by IR spectrum and elementary analysis. Sandwich-type cells were fabricated by the vacuum evaporation technique. From UV-Visible spectrum, two conclusions have been drawn. First, the composite show a widely absorption(450~600nm) in the visible. Second, there is strong reflection among 530～600nm in the visible in Au electrode. The cells were investigated recording in situ photocurrent-voltage(I-V) characteristic and photoelectric sensitivity. Owing to efficient carrier photogeneration under the application of higher voltages. At a high applied voltage of 17V,a large photocurrent multiplication rate of 103 was achievred . After analyzed, I found the photocurrent-voltage characteristic obeyd fowler-nordheim equation, which indicates charge intensification effect by tunneling injection process. Finally, a whole mechanism of photocurrent multiplication was achievred through the above experiment and analysis.