III-V Device Integration on Silicon Via Metamorphic SiGe Substrates

Abstract

A range of high performance minority carrier devices have been successfully fabricated on Si virtual substrates where threading dislocation densities (TDDs) as low as 1x106 cm-2 are routinely achieved. Minority carrier lifetime data achieved on GaAs-on-Si layers exploiting this novel SiGe buffer approach to monolithic integration (τp = 10.5 ns and τn = 1.7ns) verifies the high III-V material quality. Single junction GaAs solar cells with high efficiencies for GaAs/Si of 18.1% under AM1.5-G illumination were demonstrated. Further exploiting the novel GaAs/Si material quality, even more complex minority carrier devices including dual-junction solar cells and LEDs were fabricated, yielding high performance consistent with the high III-V/Si mobilities. In both cases, certain device metrics on SiGe outperformed identical GaAs monolithic devices. Finally, a visible laser on Si was achieved, demonstrating the success and further potential of this III-V/Si integration methodology.