Theoretical study of electronic properties of resonant tunneling diodes based on double and triple AlGaAs barriers

Abstract

In this paper, we investigated the effect of the central AlGaAs barrier width Lb2 in a resonant tunneling diode (RTD) composed by triple barriers on the current-voltage characteristics, and electronic density of free carriers. In addition, this is a comparative study on the current-voltage characteristics that are produced by a double-barriers and triple-barriers RTD. Our simulation was performed using a non-equilibrium Green’s formalism (NEGF). The results showed that the double-barrier RTD produced a higher current density than the triple-barrier RTD. However, in the triple-barrier RTD, the maximum current was obtained for lower applied bias compared to the double-barrier RTD. The peak to valley current ratio (PVCR) has been evaluated and our results indicate that the double-barrier RTD can produces a higher ratio values compared to those produced by triple-barrier RTD. Our findings also showed that for the triple-barrier RTD, the negative differential resistance (NDR) depended on the width Lb2 of the central barrier. By reducing Lb2, the NDR decreased dramatically and disappeared completely for Lb2 = 3 nm. These results open the door for designing a double and triple-barrier RTD with suitable negative differential resistances. The RTD simulation was performed using the Nanohub tool, which confirms the various results presented in this paper.