We report on the growth of GaxIn1-xAs/AlAs double‐barrier heterostructures on InP and the fabrication of GaxIn1-xAs/AlAs resonant tunneling diodes (RTDs) by metalorganic chemical vapor deposition (MOCVD). High resolution x‐ray diffraction measurements were used to evaluate the heterostructure interface quality. The RTDs achieved a room‐temperature peak to valley ratio of 7.7:1 with peak current density of 9.6×104 A/cm2. These are the best reported room‐temperature results for any reported RTDs grown by MOCVD. © 1994 American Institute of Physics.