Low-temperature growth of nanostructured InGaSb semiconductors on silicon substrates

We propose a technique for fabricating a nanostructured III–V semiconductor on a Si substrate by growing Sb-based quantum dot (QD) structures at a low temperature. The process temperature for this technique is considered to be compatible for use with silicon C-MOS processes. High-density (>1010 cm−2) and small-size QD structures were fabricated using simple optimal-growth sequences of solid-source molecular beam epitaxy (MBE). We fabricated an InGaSb QD structure on an Si (0 0 1) substrate whose surface temperature was 400 °C. We also found that the formation of a giant-dot structure can be suppressed by using optimal growth techniques, such as by slightly constraining the In composition in the QD structure, by using low-Sb-flux irradiation on the Si substrate, and by using a lower temperature to grow the QD structures.