Metal-Organic Vapor-Phase Epitaxy Growth of InP-Based Resonant Tunneling Diodes with a Strained In0.8Ga0.2As Well and AlAs Barriers

InP-based resonant tunneling diodes (RTDs) with a strained In0.8Ga0.2As well and AlAs barriers were grown by metal-organic vapor-phase epitaxy (MOVPE). Cross-sectional transmission electron microscopy (TEM) confirmed the successful formation of ultra-thin strained AlAs barriers and In0.8Ga0.2As wells. Atomic force microscope (AFM) observation revealed atomically flat interfaces in the double-barrier (DB) structures of the RTDs. We obtained a peak current density ( j P) of 1.46×105 A/cm2, high peak-to-valley current ratio (PVR) of 7.7, and a low peak voltage (V P) of 0.43 V simultaneously in the RTDs with the barrier thickness (L b) of about 6 monolayers (MLs). Maximum j P exceeded 4×105 A/cm2 in the RTDs with L b of about 4 MLs. The AlAs barrier thickness was precisely controlled by the Al-precursor-supply duration. These results indicate the potential of the practical use of MOVPE for high-speed InP-based integrated circuits with RTDs and other devices.