Propiedades ópticas y estructurales de las películas de óxido de silicio rico en silicio obtenidas por la técnica HFCVD

In this work we present the results of the analysis obtained from the deposit and characterization of thin films of silicon rich oxide (SRO). The films were obtained by hot filament chemical vapor deposition (HFCVD) technique, such films were deposited on silicon substrates p-type. The deposit of thin films was realized considering different distances from source to substrate (DFS) which were 3, 4, 5 and 6 mm. The quantity of precursors (SiO2) was controlled by the distance from the filament to the source, which was 6 mm for this work, the filament was held at 2000°C. A constant 3-minute deposit time was maintained, and the hydrogen flow level was 10 sccm. The films thickness was obtained by using the profilometry technique, the thickness range was from 200 to 600 nm. The vibrational molecular modes of the SRO films were obtained by Fourier Transform Infrared Spectroscopy (FTIR). The films of 3 mm DFS exhibit an optical transmittance of 90%. The optical energy band gap of the thin films varies from 2.2 to 3.3 eV. When an annealing process at 1000°C was carried out for one hour, the SRO films increase their photoluminescence by an order of magnitude approximately.