Investigation And Fabrication Of Organic Field-Effect Transistors Based In Pentacene

Organic Thin Film transistors (OFETs) are transistors device using organic semiconductor materials as active layers, and have got various interesting from scientist and industry. Compared with common inorganic transistors, they have two distinct advantages: low cost over a large area and low temperature fabrication on a flexible substrate. The thought of put the organic semiconductor as the active layer of the organic fhin film transistors started at 1970. Untill 1986, the first OFETs was fabricated. After more than 20 years development, there are has many evolutions of OFETs. The charge carrier mobility and on/off current ratio of the OFETs could achive the a-Si:H FETs. It is the most intresting of the low cost and flexbilty flat panel displays,such as electronic papers, radio frequency identification tags, sensors and smart cards.We successly found the solution process of pentacene thin films from organic solvent O-dichlorobenzene. The pentacene thin films obtained from different conditions were characterized by X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), and UV-vis spectroscopy. The result shows that the pentacene solution was successfully obtained at a minimum temperature of 40℃. The optimum temperature of forming pentacene thin films was 100℃.Firstly, it summarizes the general evolution history of organic electronics, introduces several key devices of organic electronic devices, such as OLED, organic unimolecular electronic, organic sensor, et al., their development and actuality. Review 20 years history of OFETs, introduce organic integrate circuit, discuss problem of OFETs, and present research hotspot of OFETs.Four device structures are introduced. The advantages and disadvantages of such structures are also discussed. Then, we sum up the applications of all kinds of OFET materials, inclouding organic semiconductor, dielectrical materials, electrode materials, substrate materials and so on. The theory of charge transport, the charge transport model and the contact of metal/semiconductor were disscused. There were also have P-type and N-type organic semiconductor.We have successfully synthesized the pentacene, and characterized it by infrared absorption spectra (IRAS), mass spectra (MS), element analysis, x-ray diffraction (XRD) and atom force microscopy (AFM). The pentacene is insoluble and cannot be characterized with NMR-spectroscopy. The pentacene OFETs have been fabricated.We used the ITO-glass as the substrate, used the polymide as the dielectrical layer fabricated the all organic semiconductor field effect transistors, and received better C-V curves.