Polymer pyrolysis to nanoceramics is employed for the production of photo-luminescent thin film samples, consisting of Si-nanocrystals dispersed in silica matrix. Thin films were deposited on Si wafer by spin-coating technique from a triethoxysilane-clerived sol-gel solution. This is a fast process and a low cost technique. Samples were annealed at different temperatures between 600 degrees C and 1300 degrees C, under N-2 gas atmosphere. Structural evolution and luminescence from Si-ncs vs. temperature were investigated by FT-IR absorption spectroscopy and photo-luminescence. Absorption spectrum of As-Prep sample shows several vibrational bands due to Si-H, C-H-x, and Si-O-Si structural units, without any appreciable luminescence. Silica phase segregation and intense PL (790 nm) due to Si-ncs were observed on annealing at T> 1000 degrees C. (c) 2007 Elsevier B.V. All rights reserved.