Bottom-gate OFET structure

Fig. 4. Schematic of top-contact/bottom-gate OFET device and structures of the CPB precursors (polymer and silane crosslinkers) employed in this study.

Fig. 1 Schematic drawing of the structures of four kinds of typical OFET devices (a) Top contact/bottom gate (TC/BG) (b) Top view of (a), W channel width, L channel length (c) bottom contact/bottom gate (BC/BG) (d) sandwich contact/bottom gate (SC/BG) and (e) bottom contact/top gate (BC/TG)...

Beeause of the high euring temperature of the introdueed polyimide film, it is inapplieable to polymer substrates. Therefore, a eommereially available eoating varnish Beetron (based on modified alkyd ehemistry), favoured beeause of the low euring temperature of about 80 °C, is spin eoated onto a silieon substrate. It is eured in a eonveetion oven at 80 °C for 30 min, resulting in a 1 pm to 1.5 pm thiek film. In eontrast to the OFETs mentioned in this ehapter so far, the transistor on the Beetron varnish uses bottom gate and titanium top drain and source contacts, structured by a shadow mask. The latter is due to the lack of chemical resistance of the varnish towards solvents. 

Schematic (not to scale) of typical top-gate staggered and bottom-gate coplanar device structures used in OFETs.

Fig. 1.2 Four device architectures for OFET a bottom-gate top-contact structure b bottom-gate bottom-contact structure c top-gate top-contact stmcture d top-gate bottom-contact structure...

As a low-cost alternative to traditional inorganic semiconductors based transistors, organic field effect transistors are ideally positioned for applications such as radio frequency ID tags, sensors, and smart banknotes [36-40]. An archetypical structure of a bottom-gate top-contact OFET is shown in Scheme 3.7a. Other device architectures have also been employed depending on the relative... 

Scheme 3.7 a) a t) ical structure of bottom-gate top-contact OFET b) bottom-gate top-contact c) bottom-gate bottom-contact d) top-gate bottom-contact e) top-gate top-contact. 

Fig. 13 Schematic of the bottom-gate oiganic field-effect transistors (OFETs) with (a) top contact and (b) bottom contact structures. Schematic diagram of a (c) top-gate/bottom contact OFETs using a standard TFT device structures and (d) top-gate/top contact is also shovm. (Reproduced...

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