Deposition and annealing of tantalum pentoxide films using 172 nm excimer lamp

We report the growth of thin tantalum pentoxide films on Si 100. by photo-assisted chemical vapor deposition photo-CVD.from a tantalum ethoxide source using an excimer lamp XeU2 , 172 nm.. The effects of substrate temperature and ultraviolet UV.annealing on the film formed have been studied using ellipsometry and Fourier transform infrared spectroscopy FTIR.measurements. The FTIR spectra reveal suboxide formation in the as-deposited films that disappeared after subsequent UV annealing. The electrical properties of the films were determined by capacitance–voltage C–V.and current–voltage I–V.techniques on AlrTa2O5rSi metal oxide semiconductor structures. The I–V characteristics of both as-deposited and annealed films can be described by the Fowler–Nordheim tunneling mechanism. Dielectric constant values of about 24 were readily achievable in the as-deposited films that are comparable to those obtained by other techniques. q2000 Published by Elsevier Science B.V. All rights reserved