| Summary: | 碩士 === 國立交通大學 === 物理研究所 === 90 === In order to solve the problem of the low carrier mobility in conjugated polymer, we use EBL(electron beam lithography) to fabricate the horizontal device with the electrodes parallel to electric current direction. The horizontal device is made up of Au/MEH-PPV/Au, and the hole carriers transport along the intra-chain instead of inter-chain hopping. Therefore, it is expected that there will be less resistivity and higher carrier mobility. We change the distance between the Au electrodes, ranging from 0.9 micron to14.7 micron, and measure the current-voltage curve to get the hole mobility in the horizontal device. It is found that the carrier mobility is about 102 to 103 much larger than the traditional sandwich structure. Besides, there is little dependence between the hole mobility and carrier transport distance. As the electrode distance is changed, we also change the measurement temperature to understand the temperature dependence of hole mobility. With the decrease of the temperature, the hole mobility decreases exponentially. In addition, the thermal activation energy gap is approximately half of that of the sandwich device.
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