Saturated drift velocity

For high-frequency devices, the breakdown electric field strength is not as important as the saturated drift velocity. In SiC, this is 2 x 10 cm/sec [5, 6], which is twice that of Si. A high-saturated drift velocity is advantageous in order to obtain as high-channel currents as possible for microwave devices, and clearly SiC is an ideal material for high-gain solid-state devices. 

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Bandgap at 300K (eV) 1.43 Saturated Drift Velocity (em/sec) 2.0x10 Drift Mobility... 

It bas a high saturation drift velocity, wbicb enables devices to operate at higher frequencies. 

Silinsh et al. (1989) applied their thermalization procedure to naphthalene and anthracene at low temperatures, 35 K or less. A stationary state was envisaged in the presence of an external field. Calculations have been performed for the saturation drift velocity, friction coefficients, and effective mass as functions of the external field. The conclusions are almost the same as for pentacene. 

TABLE 10.3 Saturation Drift Velocity in High-Mobility Liquids... 

The different polytypes exhibit different electronic and optical properties. The bandgaps at 4.2 K of the different polytypes range between 2.39 eV for 3C-SiC and 3.33 eV for the 2H-SiC polytype. The important polytypes 6H-SiC and 4H-SiC have bandgaps of 3.02 eV and 3.27 eV, respectively. All polytypes are extremely hard, chemically inert, and have a high thermal conductivity. Properties such as the breakdown voltage, the saturated drift velocity, and the impurity ionization energies are all specific for the different polytypes. 

For 1.0-1.6-/[xm spectral range, InGaAs lattice matched to InP has been considered for photoconductive detectors. It is an attractive material due to its high saturation drift velocity. Compared to semi-insulating InP, however, semi-insulating InGaAs materials obtained so far tend to be less resistive ( 10 S2-cm) with a typical dark resistance in the range of kf2, which compromises the device performance. 

That one cannot explain an ultra high mobility and a low saturated drift velocity with conventional theory cannot be over emphasised. The latter requires a large electron phonon interaction while the former requires low scattering and a concomitant low electron phonon interaction according to conventional wisdom. The resolution of this apparent paradox is found in the motion of the acoustic solitaacy mve polaron descri2>ed in the following article. 

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