Influence of Al content x on hot electron noise in Al/sub x/Ga/sub 1-x/As n/sup +/nn/sup +/ devices: comparison with GaAs

Hot electron noise measurements are performed in Si doped Al/sub x/Ga/sub 1-x/As n/sup +/nn/sup +/ devices, for three different Al concentrations: x=0.15, 0.2, 0.25. Noise temperatures are obtained using a pulsed measurement technique as functions of electric field and frequency. Longitudinal diffusion coefficients D(E) are deduced at 4 GHz. Results are analyzed through the scattering mechanisms which greatly affect the electron velocity properties of Al/sub x/Ga/sub 1-x/As materials. Comparisons with n/sup +/nn/sup +/ GaAs devices are made.<
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