Negative-differential-resistance characteristics in a triangular-barrier resonant tunnelling switch

A triangular-barrier switch whose structure center possesses a p-type delta-doped (delta(p(+))) quantum well has been fabricated. By numerical simulation based on the transfer matrix method, the operation of the device is demonstrated. In the (delta(p(+))) well, a miniband is formed. An N-shaped negative-differential-resistance (NDR) phenomenon is observed in the current-voltage (I-V) characteristics because of the resonant tunnelling effect. In our experiments, the I-V characteristics present a sensitive dependence on the well width. The dependence of the tunnelling property on the well width and the influence of temperature upon the NDR characteristics are all investigated in this paper.