Flexible organic transistor electronic devices

Flexible organic transistors have been attractive for driving electronic devices such as paper-like displays, low-cost identification tags, and flexible photovoltaic cells. These devices may not be fabricated using conventional inorganic materials. In order to commercialize such devices, it is necessary... 

Thermally and mechanically stable thin film formation is indispensable for fabrication of practical electronic devices such as organic light-emitting diodes, field-effect transistors, and particularly for flexible electronic papers. There are two approaches for formation of thermally and mechanically stable thin films. One is formation of glassy semiconductors retaining ordered structures by cooling from liquid-crystalline states [94]. The other approach is polymerization of liquid-crystalline semiconductors with a reactive moiety. 

In 2004, Someya et al. [24] improved the fabrication technique for these devices and developed an electronic artificial skin. In this work, once again, organic transistors were not used as sensors in themselves but as addressing elements of a flexible matrix which was used to read out pressure maps... 

Figure 6.9 Images of a Braille display (a) the flexible Braille sheet display using IPMC actuator array (b) the device assembly (c) circuit diagram of the Braille sheet display (Reprinted with permission from Kato, Y., Sekitani, T., Takamiya, M. et al. Sheet-Type Braille Displays by Integrating Organic Field-Effect Transistors and Polymeric Actuators, IEEE Trans on Electron. Devices, 54 (2), 202-9. Copyright (2007) IEEE).

Whereas inorganic polycrystalline or amorphous silicon technologies are well established for the realization of TFTs, high process temperatures [3-5] are required during their production and are one of the reasons for a limited compatibility with flexible plastic substrates. Here, organic field-effect transistors (OFFTs) are of special interest since the usual production at low temperature allows for the realization of flexible electronic devices, while still being comparably inexpensive. 

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