Schottky MESFET

In a MESFET, a Schottky gate contact is used to modulate the source-drain current. As shown in Figure 14-6b, in an //-channel MESFET, two n+ source and drain regions are connected to an //-type channel. The width of the depletion layer, and hence that of the channel, is modulated by the voltage applied to the Schottky gate. In a normally off device (Fig. 14-9 a), the channel is totally depleted at zero gate bias, whereas it is only partially depleted in a normally on device (Fig. 14-9 b). 

Fig. 9. A Schottky barrier gate used in the metal-semiconductor field-effect transistor (MESFET) in AT T gallium arsenide microchips. The tiny gate is only one micrometer wide (1/25,400 inch). The gate electrode is deposited before the ion-implantation process so that the gate material will shade the channel under it from the ion rain that doses the exposed material. (AT T Technology)...

State-of-the-art Schottky diodes operate up to 400°C [28] see FIGURE 5. The stability of the Schottky diodes limits the maximum temperature of operation of SiC MESFETs since SiC itself can withstand much higher temperatures. State-of-the-art ohmic contacts can operate at significantly higher temperatures than Schottky contacts. 

GaAs Complimentary JFETs By ion implantation, a GaAs enhancement mode JFET has been developed in parallel with the GaAs Schottky-barrier FET or MESFET. It is useful in FET logic DCFL). Creates an ultra low power device with applications to the static RAM (55). 

MESFET Schottky gated field-effect transistor... 

JFET junction field-eifect transistor MESFET MFTF metal Schottky Held-effect transistor Mirror Fusion Test Facility... 

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