Top-gate, FETs

FIGURE 10.10. (a) The chemical structure of F8T2. (b) Schematic diagram of the top-gate polymer FET. (Adapted from Ref. 26.)... 

Figure 25.3 Scheme of the three major steps of FET fabrication. After preparing source drain contacts by Ag paste (a) the gate insulator is fabricated by a two-step temperature process of para-cyclophane (b). Finally, by thermal evaporation of Au the top-gate contact of 20 nm thickness is deposited (c). An image of the resulting structure is shown in (d) for a DIP crystal FET. 

Field-effect Transistors Enzyme FETs and immuno FETs (IMFETs) are based on principles similar to those valid in potentiometric membrane biosensors. The enzyme is immobihzed on top of the ion-selective membrane on the gate of the FET. For construction of ENFETs, usually double-gate FETs are used employing one gate as a reference system, covered only with a layer of the immobilization matrix, and allowing for the real-time compensation of pH modulations, temperature, and drift. Mostly, pH-sensitive FETs (ISFET)... 

Figure 16.5 Typicai FET configurations (a) top contact/bottom gate (TC/BC), (b) bottom contact/bottom gate (BC/BC) and (c) bottom contact/top gate (BC/TC).

Figure 10.10 Construction of FETs with individual (a and b) and collective (c) nanotubes. (a) AFM image of an FET composed of gold source and drain electrodes and an individual carbon nanotube as a channel. A heavily doped wafer served as a back gate electrode. Alternatively, an individual top gate electrode made of Ti can be employed...

Fig. 17.2 (a) Top-contact, bottom-gate device (b) bottom-contact, bottom-gate device (c) bottom-contact, top-gate device (d) working mechanism of a FET device with p-type materials (e) transfer characteristic curve of FET device and (f) output characteristic curve of FET device... 

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