Current noise in N-type AlxGa1 −xAs

Abstract Current noise in Si-doped Al x Ga 1 − x As, grown by means of M.O.V.P.E., was investigated in the frequency range 1 Hz–100 kHz and in the temperature range 80–340 K. The measured noise over and above thermal noise was found to depend quadratically on the applied electric field, which means that it was caused by resistivity fluctuations. The noise consisted typically of two types of components: 1/ f noise and one or two generation-recombination ( g - r ) components with Lorentzian-shaped frequency dependence. From the temperature dependence of the g - r noise relaxation times, it was possible to calculate the activation energies and capture cross sections of two different deep electron traps.