MeV ion-induced suppression of resonance current in InP-based resonant tunneling diodes

We present the results of an experiment on 12.5 MeV Si4+ ion-irradiated InP -based resonant tunneling diodes. Radiation damage suppresses the entire re sonance in direct proportion to the ion fluence. The suppression is not cau sed by a change in the tunneling barrier heights or widths, as previously t hought; nor is it caused by radiation-induced increases in the leakage curr ent. In fact, none of the internal parameters such as the Fermi energy and the resonant energy of the quantum well are expected to be greatly altered by the irradiation. We propose that radiation-induced disorder decreases th e resonance current by scattering carriers out of the reduced-dimensional r egion of k space in which tunneling is allowed. (C) 2000 American Institute of Physics. [S0003-6951(00)01918-5].