Measurement of the electron saturation velocity in an AlGaAs/InGaAs quantum well

Abstract

The dependence of the average electron-drift velocity on the electric field strength is measured for a twodimensional electron gas in a quantum well of an AlGaAs/InGaAs heterostructure in the temperature range 200-400 K. It is shown that the saturation velocity varies from 1.55·10 7 to 1.3·10 7 cm/s in this temperature range and substantially exceeds the velocity in bulk gallium arsenide.

GaN HEMT based high energy particles detection preamplifier

“…Si GaAs SiC GaN Band gap E G [eV ] [17] 1.1 1.42 2.3~3.3 3.44 Critical field strength E C [10 6 V /cm] [17] 0.4 0.5 4 6 Mobility µ cm 2 /V •s [11,14] 1450 5000 900 2000 Thermal conductivity κ [ W /cm•K] [17] 1.5 0.5 3~5 1.3 Electron saturation velocity ve sat 10 7 cm /s [11,14,1] 1 1.4 2.2 3 Lattice Constant (Å) [11,17] 5.43 5.65 3.08 3.19 Coefficient of Thermal Expansion α [10 −6 × K −1 ] [11,13] 2.6 6.86 4.2 5.6 The thermal conductivity κ of the GaN is lower than Si and SiC. The implication of it is that GaN has lower power dissipation, limiting it to lower voltages, if one intends to use it for power devices.…”

A method for determining the ambipolar diffusion length and carrier lifetime in GaAs p-i-n diodes

“…It was shown in [9] that in a frequency range of 2-20 GHz, the values of IL for microwave GaAs diodes are virtually constant; therefore, any frequency in the aforementioned frequency range can be chosen for measurements. Figure 2 shows the dependences of R s on the radius of the active region r 0 for diodes manufactured on a single structure, which were measured at the frequency f = 10 GHz for four values of the forward current I F : 5, 10, 15, and 20 mA.…”