In situ ultraviolet-assisted pulsed laser deposition of Y2O3 thin films

Ultraviolet (UV)-assisted pulsed laser deposition (PLD) of thin Y2O3 films at moderate substrate temperatures has been investigated. Highly textured (111) oriented Y2O3 layers, whose crystalline quality is similar to that usually obtained by conventional PLD at temperatures in excess of 600 degrees C, have been grown on Si substrates under an oxygen pressure of 9 x 10(-2) Torr at only 405 degrees C. The refractive index values of these layers, assessed using spectroscopic ellipsometry, were similar to reference handbook values. X-ray photoelectron spectroscopy investigations showed that the UV-grown films exhibited a significantly smaller proportion of physisorbed oxygen than those grown under optimum conditions but without UV irradiation. This indicates that the ozone and atomic oxygen species, formed by UV radiation induced photodissociation, which are more reactive than molecular oxygen, promote the crystalline and stoichiometric growth at such moderate temperatures. (C) 1999 The Electrochemical Society. S1099-0062(99)03-051-5. All rights reserved.