Low-temperature growth of germanium quantum dots on Silicon Oxide by inductively coupled plasma CVD

We report on the fabrication of germanium quantum dots on silicon oxide and their growth mechanism. Germanium quantum dots were deposited by inductively-coupled plasma CVD at 400°C. Gold nanoparticles, attached to silicon oxide through a self-assembled monolayer, were adopted as catalysts to allow access to a vapor-liquid-solid process. The density of polycrystalline germanium dots is 1.46 × 10¹¹ cm^-2, which is consistent with the density of the gold nanoparticles. The mechanism by which the undesirable gold catalysts are removed during the germanium dot growth process has been elucidated. This technique provides a low-temperature process for the fabrication of devices consisting of germanium quantum dots on an insulator surface.