Fabrication of Si nanodot arrays by plasma enhanced CVD using porous alumina templates

Si films with nanodot arrays were prepared on anodic aluminium oxide (AAO) templates by plasma enhanced chemical vapor deposition (PECVD). The structure and morphology of the samples were characterized using X-ray diffraction spectroscopy, scanning electron microscopy and transmission electron microscopy. The deposition mechanism was discussed in view of the reactions and the resultants in the discharge as well as the impact on AAO templates. It was found that the size of Si nanodots could be controlled by the pore diameter of alumina substrate. Photoluminescence spectra of the samples showed a remarkable blue shift with the size of Si nanodots decreasing. Si films with such nanodot arrays were demonstrated to have good behavior of electron field emission, the turn-on voltage is about 7 V/μm.