QUANTUM-SIZE EFFECTS ON PHOTOLUMINESCENCE FROM SI NANOCRYSTALS IN PECVD SILICON-RICH-OXIDE

Red-shift of photoluminescence (PL) spectra and increasing intensity a fter subsequent annealing have been observed in plasma-enhanced chemic al-vapor-deposition (PECVD) silicon-rich-oxide (SRO). Based on FTIR re sults, however. PECVD SRO does experience chemical and structural chan ges during post-deposition annealing and becomes denser, Besides, the enhanced tunneling characteristics of MOS capacitor using SRO thin fil m as injector due to nanocrystalline silicon (nc-Si) in SRO thin film is also observed. These results strongly suggest the luminescence and the enhanced tunneling characteristics originate from the quantum size effect of nc-Si. In this paper, a Si-island model is proposed to deli neate the gradual red-shift phenomenon of PL spectra.