| A microwave time-of-flight technique has been used to measure electron drift velocities in n-GaAs and n-In(,0.53)Ga(,0.47)As over a wide range of temperatures and electric field strengths.;Electron drift velocities in n-In(,0.53)Ga(,0.47)As have been determined for electric field strengths from about 15 kV/cm to 163 kV/cm at various temperatures from 95 K to 300 K. The electron drift velocity in n-In(,0.53)Ga(,0.47)As was also found to be a continuously decreasing function of increasing electric field over the entire range of temperatures and field strengths investigated. The electron velocity-field characteristic for n-In(,0.53)Ga(,0.47)As exhibits a higher peak velocity and a lower high-field velocity than is obtained with GaAs. In addition, the negative differential mobility is larger in In(,0.53)Ga(,0.47)As at all temperatures and field strengths investigated. Finally, the variation of velocity with temperature at a fixed electric field strength in In(,0.53)Ga(,0.47)As was found to be about one third the variation in GaAs.;The velocity-field characteristics reported in this work are the first measurements of temperature dependent drift velocities using the microwave time-of-flight ever reported. Furthermore, the velocities measured in GaAs have been measured, at most temperatures, for field strengths twice as high as any previously reported measurement of temperature dependent velocities. Finally, the electron drift velocity measurements in n-In(,0.53)Ga(,0.47)As performed in this work are the only known measurements of drift velocities in this material for electric field strengths in excess of (TURN)3-4 kV/cm.;Electron drift velocities in n-GaAs have been measured at temperatures from 95 K to 385 K and at electric field strengths of up to 236 kV/cm. The present results are in excellent agreement over the entire temperature range with previously reported measurements at lower electric fields. The electron drift velocity in n-GaAs has been found to decrease monotonically at all temperatures, and over the entire range of electric field strengths investigated. |
