Multi-heterojunction InAs/GaSb nano-ridges directly grown on (001) Si.

We report on multi-stacked InAs/GaSb nano-ridges directly grown on (001) patterned Si substrates by metal-organic chemical vapor deposition (MOCVD). Uniform GaSb and InAs nano-ridges were demonstrated with optimized growth parameters. By adjusting the switching sequences, we also obtained defect-free InAs/GaSb and GaSb/InAs interfaces. Based on these fine-tuned growth conditions, multi-stacked InAs/GaSb nano-ridges were developed and characterized. The nano-ridges showed uniform morphology from scanning electron microscopy (SEM), and no observable crystalline defects were detected at the hetero-interfaces by transmission electron microscopy (TEM). These InAs/GaSb nano-ridges show great potential for applications in nano-scale tunneling devices and long wavelength light emitters and detectors. The demonstrated growth techniques provide helpful insights for the growth process control of 6.1 Å family compound semiconductors directly on Si by MOCVD.