Temperature-dependence of negative differential resistance in GaN/AlGaN resonant tunneling structures

We report a systematical study of the temperature-dependence of negative deferential resistance (NDR) from double-barrier Al0.35Ga0.65N/GaN resonant tunneling diodes grown by plasma-assisted molecular-beam epitaxy on free-standing GaN substrates. The current‐voltage (I‐V) characterization was done in the 6‐300 K temperature range. A clear NDR signature was observed for mesa sizes of 4 × 4 μm 2 at temperatures below 130 K. This suggests that the resonant tunneling is the dominant charge transport mechanism in our devices. (Some figures may appear in colour only in the online journal)