Organic Transistor-based Integrated Circuits

To read out pressure images from the sensor matrix, integrated circuits such as decoders and selectors are needed. We have also manufactured those integrated circuits with organic transistors and characterized the electronic performance of the system. 

Compared with conventional photolithography, laser drilling is a dry process and keeps the surface of polyimide gate dielectric layer away from water, etching solution, or other solvent, which often degrade the polyimide surface. We have confirmed that the electronic performance of transistors with laser via holes is identical with that without laser via holes. 

If we consider the reasonable form of the practical artificial skin system, it is most likely that the pressure data read out from organic integrated circuits would be transferred to silicon chips. In this sense, some readers may want to claim that it is not necessary to build a decoder or selector with organic transistors. The denser and the larger-area integrated circuits, however, require the more complicated packaging and fine wiring, which cannot be easily achieved with silicon at reasonable cost. Thus our opinion is that it is very important to realize func- 

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OFETs constructed on a silicon wafer do not lake advantage of one of the main interest of organic materials, namely the possibility of building electronic devices on plastic substrates. A second important drawback of the silicon-based structure is the difficulty to individually address the gale of transistors built on the same wafer, which would prevent the achievement of integrated circuits. 

Metal oxide semiconductor field-effect transistors (MOSFETs) are field effect transistors with a thin film of silicon dioxide between the gate electrode and the semiconductor. The charge on the silicon dioxide controls the size of the depletion zone in the polype semiconductor. MOSFETs are easier to mass produce and are used in integrated circuits and microprocessors for computers and in amplifiers for cassette players. Traditionally, transistors have been silicon based but a recent development is field-effect transistors based on organic materials. 

Integrated circuits (ICs) based on organic transistors have been reported in a few pnblications [12-15]. In this section, a scalable integrated circuit [16,17] for e-skins is described. In order to read ont pressure data from the sensor arrays, decoders and selectors connected to word lines and bit lines, respectively, are needed in addition... 

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