p+/n+ In0.53Ga0.47As tunnel junctions with room temperature peak to valley ratio of 9:1 are demonstrated. The device structures were grown on both InP and GaAs (4% lattice mismatch) using Chemical Beam Epitaxy (CBE). Be and Si were used as dopants. The devices grown on InP exhibit room temperature peak current in excess of 1000 A/cm2. The peak current of 452 A/cm2 achieved on lattice mismatched material (GaAs) is comparable to the highest results previously reported on lattice matched material (InP). Finally, The device characteristics and the influence of different fabrication steps on the performance of these devices are discussed based on temperature dependent I-V measurements.