Fabrication and dc, microwave characteristics of submicron Schottky‐collector AlAs/In0.53Ga0.47As/InP resonant tunneling diodes

We report the fabrication and dc, microwave characteristics of 0.1 μm, Schottky‐collector resonant tunnel diodes (SRTDs) in the AlAs/In0.53Ga0.47As/InP material system. Devices with contact areas as small as 0.05 μm2 have been fabricated using electron beam lithography with an interrupted footprint T‐gate process. SRTD’s fabricated with 1.4 nm AlAs barriers exhibited a 5×105 A/cm2 peak current density at 0.95 V and a −19 mS/μm2 peak negative conductance. The devices incorporate fully depleted P‐doped cap layers to suppress surface leakage currents. From the measured dc and microwave characteristics, a maximum frequency of oscillation fmax=2.2 THz is estimated.