n+ InGaAs/nGaAs heterojunction Schottky diodes with low barriers controlled by band offset and doping level

We have fabricated and measured low barrier (30-150 meV) Schottky diodes using n+InGaAs/nGaAs pseudomorphic structures with up to 1.5% lattice mismatch. The I-V measurements at temperatures from 4 to 200 K show rectifying behavior and indicate transport mechanisms which range from tunneling to thermionic emission. The transport properties and barrier height determinations indicate that the band offset is predominantly in the conduction band. The barrier height increases with In concentration, which is consistent with band calculations based on previous experimental data.