Low pressure chemical vapor deposition growth of silicon quantum dots on insulator for nanoelectronics devices

We present a comparative study of nucleation and growth of Si quantum dots on SiO2, SiOxNy and Si3N4 substrates using silane low pressure chemical vapor deposition LPCVD.at low temperature 570–6108C.. The samples are investigated by atomic force micoscopy AFM., scanning electron microscopy SEM., high resolution transmission electron microscopy HRTEM.and spectroscopic ellipsometry SE.. We show that the chemical nature of the surface, precisely, the presence of SiO bonds, decreases the Si quantum dot density. By optimising the deposition parameters, a Si dot density of 1012 cmy2 can be obtained below 6008C on a pure Si3N4 surface. The influence of hydrogen, provided by silane decomposition, on the Si nucleation mechanism will be discussed. q2000 Elsevier Science B.V. All rights reserved