| Summary: | 碩士 === 國立臺灣海洋大學 === 電機工程學系 === 101 === This thesis studies the performance of the organic nonvolatile memory device using the metal nanopaticles as the floating gate. The devices used indium tin oxide (ITO) substrate as the gate electrode. Then tantalum pentoxide (Ta2O5) was evaporated dire- ctly onto the substrate to form a control layer, followed by metals sputtered or evapo- rated to form the nanoparticle as the floating gate. Poly(4-vinyl-phenol) (PVP) and re- gio-regular Poly(3-hexylthiophene) (rr-P3HT) were spin-coated sequentially to form a tunnel layer and an active layer, respectively. Finally, Gold (Au) source/drain electro- des were sputtered atop. The organic field-effect transistor with the floating gate was verified to be workable by investigating the hysterestic phenomena, current-voltage characteristics, retention time, and endurance of the device. Owing to the easy oxide- tion of aluminum (Al), the Al nanoparticle is prepared by sputtering, and then annea- led under the ambient condition to form a shell of Al2O3 on the surface, which can act as the tunnel layer without the PVP layer. The performance of floating gates with and without the overcoat layers of PVP are measured for the comparison in details. The experimental results show that both devices exhibit the hysteristic phenomena, indica- ting that Al nanoparticles can store the charge, but the charge-storage ability is better for the former than the latter, because the former shows a wider memory window. For the respect of the retention time, the residue quantity of stored charges for devices with the PVP layer is 81.2% of the initial one after 3200 s; in contrast, the device without the PVP layer has the residue charges of 43.4% after the same time. For the performance of endurance, the memory window of devices with the PVP layer re- mains 59.6% of the initial one after 50 program/erase cycles; but the remaining me- mory window of devices without the PVP layer is 6% of the initial one. All these re- sults indicate that we have successfully fabricated the organic nonvolatile memory de- vice using the Al nanoparticle as the floating gate in the present work, and we found that the performance of the memory device with the PVP layer is superior to that of the one without the PVP layer.
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