Numerical simulation and experimental realization of δ-doped single barrier resonant tunneling diodes

In this study, a new negative differential resistance (NDR) device based on a δ-doped single barrier resonant tunneling structure is presented. Numerical simulation is utilized to analyze the resonant tunneling mechanism of the proposed device. Calculated results reveal that the N-shaped NDR is due to the resonant tunneling through a quasibound state inside the V-shaped quantum well generated by the 6-doped layer. The peak doping concentration of the δ-doped layer in the barrier region plays a crucial role in determining both the onset and the peak-to-valley current ratio (PVCR) of the NDR. Preliminary experimental results based on the InGaAs/InP system grown by metalorganic chemical vapor deposition are reported for the first time. With a peak concentration of around 5 × 10¹⁸ cm^-3 in the δ-doped layer, a strong NDR with a PVCR of about 1.11 at room temperature has been observed.