DIRECT FORMATION OF NANOCRYSTALLINE SILICON BY ELECTRON-CYCLOTRON-RESONANCE CHEMICAL-VAPOR-DEPOSITION

We have confirmed the direct formation of nanosized crystalline silico n during the deposition of amorphous silicon layers by electron cyclot ron resonance chemical vapor deposition (ECRCVD) on silicon and silico n-dioxide substrates. Two photoluminescence (PL) peaks at 680 and 838 nm were observed at room temperature from the samples. From cross-sect ional high-resolution transmission electron microscopy (HRTEM) measure ments, it was confirmed that nanosize silicon crystallites of 3-5 nm i n diameter were randomly distributed throughout the amorphous silicon layer. Theoretical calculations using quantum size effects gave an ave rage crystalline size of 4 nm which was consistent with the Fl, peak e nergy at 680 nm obtained from the sample. Also, the size of the crysta llites could be controlled by the change of the substrate temperature during the deposition process. (C) 1997 American Institute of Physics.