InAs/GaAs nanostructures grown on patterned Si(001) by molecular beam epitaxy

The potential benefit from the combination of the optoelectronic and electronic functionality of III-V semiconductors with silicon technology is one of the most desired outcomes to date. Here we have systematically investigated the optical properties of InAs quantum structure embedded in GaAs grown on patterned sub-micron and nanosize holes on Si(001). III-V material tends to accumulate in the patterned sub-micron holes and a material depletion region is observed around holes when GaAs/InAs/GaAs is deposited directly on patterned Si(001). By use of a 60 nm SiO₂ layer and patterning sub-micron and nanosize holes through the oxide layer to the substrate, we demonstrate that high optical quality InAs nanostructures, both quantum dots and quantum wells, formed by a two-monolayer InAs layer embedded in GaAs can be epitaxially grown on Si(001). We also report the power-dependent and temperature-dependent photoluminescence spectra of these structures. The results show that hole diameter (sub-micron versus nanosize) has a strong effect on the structural and optical properties of GaAs/InAs/GaAs nanostructures.