G‐R noise in GaAs/Al0.4Ga0.6As resonant tunneling diodes

Low‐frequency excess noise was measured from GaAs/Al0.4Ga0.6As resonant tunneling diodes. The noise power spectra of the fluctuating voltage across the devices exhibit two distinct bumps in a 1/f background. One dominates at T≳210 K and the other one at 140 Kbumps demonstrated significant temperature dependences. In this paper we show that capture and emission energies of the traps can be obtained from the temperature and bias dependences of the voltage noise spectra. Our experimental results showed that the high temperature G‐R noise has a emission activation energy of ∼400 meV and capture activation energy of ∼200 meV, suggesting that the noise originates from DX centers. The origin of the low temperature G‐R noise is unclear. In addition, our analyses indicated that the high temperature G‐R noise involves a hopping process whereas the low temperature G‐R noise may arise from an equilibrium trapping and detrapping process.