The transistor based on organic semiconductor may not be able to replace Si technology in fast response device product such as CPU. However, for many other applications such as in address cell circuit for display device such as OLED (PLED, LED), its performance is good enough.
The current from drain Id and transconductance gm are proportion to the charge carrier mobility. Both Id and gm are two important characters to show the performance of the device. Large Id means low resistance of the device, which result in small size of the device. Large gm means high amplifying capability that also result in the reduction of device size. Mobility has big effect to both Id and gm. Device physics model (simulation) can be found in many text book.
For organic semiconductor, its mobility is usually much smaller than crystal Si material. The best value obtained so far is 5 cm2/V-S (some lab claims that 10 cm2/V-s). How can engineer improve organic transistor performance? A complete article posted in Organice device group
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