Fabrication and Performance Improvement on All Ink-Jet Printed Flexible Organic Thin Film Transistor

With the advancement of the organic electronic material, many flexible electronics applications appear. Within all these applications, OLED, LCD, e-paper, RFID-tag, sensor , solar cell, etc. are some of the most well-known examples. In addition to develop new materials, associated solution process were also investi閘極d seriously with an attempt to improve manufacturing efficiency as well. To satisfly the low temperature processing requirements for plastic substrate, the ink-jet printing has become one of best candidate for developing the next-generation fabrication process for flexible electronics due to its high degree of freedom, high accurate, low cost, etc.
In this thesis, the printhead made by MicroFab Technologies, Inc. was integrated with the newly developed pneumatics controller system, piezoelectric driver system, ink-jet observing system, substrate positioning system and software to achieve stable fabricating process with highly yield and highly repeatable. Moreover, this newly developed system can minimize the device and perform accurate fabrication requirements such as controllable channel length, film thickness, etc. OTFT and silver conducting lines were successfully fabricated in this thesis.
The fabrication process used PI tape as the substrate, PEDOT/PSS doping EG as the conducting material, PVP blend PMF as the dielectric layer, P3HT or pentacne precursor as the active layer, to arrive at an all ink-jet, all organic OTFT, To further improve the electric performance techniques such as new package, reducing thickness of active layer, surface treatment, and investigate the influence of channel length and dielectric layer thickness, etc. were all integrated in order to obtain the best OTFT circuitry performance.