Microwave Noise of Hot Electrons in Al x Ga 1-x As Channel

We present experimental results of hot electron noise in Si doped n + nn + Al x Ga 1-x As structures with x=0.15, 0.2 and 0.25 using H.F.pulsed noise measurements. Noise temperature and longitudinal diffusion coefficient as functions of field strength are compared with Si doped GaAs data. Results are discussed from the point of view of electron scattering mechanisms. The possibility of self-heating effects in AlGaAs devices influencing hot electron noise temperature measurements have been also investigated.