The formation of Si quantum dots on SiO2 by chemical vapor deposition of SiH4 has been investigated in the range from the submonolayer to the complete coverage with Si. In order to investigate the very early stages of the nucleation process of Si on SiO2, the energy filtered transmission electron microscopy has been chosen as the main characterization technique, because of the high spatial resolution typical of the transmission electron microscopy analysis, coupled to the compositional information obtained by the electron energy loss spectroscopy. The plan view configuration has been used to measure the dot size distributions down to dimensions of about 1 nm, and in cross section to evaluate the dot wetting angle. For all the several experimental conditions, a wetting angle distribution has been obtained and has shown to be centered at about 90°. Data on the dot size distributions are shown and discussed in the framework of a continuous nucleation model, which has been implemented to take into account the dot coalescence process contribution. Through the comparison with experimental data the relevant thermodynamic parameters of the process have been evaluated: the critical radius, the free energy barrier for nucleation, and the concentration of nucleation sites.

A study was conducted on metal-oxide-semiconductor (MOS) capacitor and transistor (MOSFET) structures containing a plurality of self-assembled silicon quantum dots incorporated in SiO2. The array of Si islands with an average diameter of a few nanometers was realized, by depositing a subnanometer silicon layer on top of very thin SiO2 film with chemical vapor deposition (CVD). As such, the memory effect were demonstrated by the flat-band shift in the capacitors, or the threshold voltage shift in the transistors, after write and erase operations achieved by electron tunneling through the tunnel oxide

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