Ultraviolet-assisted pulsed laser deposition of thin oxide ®lms

The properties of thin Y2O3, ZnO, and Ba0.5Sr0.5TiO3 ®lms grown using an in situ ultraviolet (UV)-assisted pulsed laser deposition (UVPLD) technique have been studied. With respect to ®lms grown by conventional PLD under similar conditions but without UV illumination, the UVPLD grown ®lms exhibited better structural, optical, and electrical properties, especially for lower substrate temperatures. These improvements can be explained by the combined action of several processes. First, high energy UV photons and ozone ensure a better in situ cleaning of the substrate prior to the deposition. Second, the presence of ozone and atomic oxygen formed by photodissociation of molecular O2 promotes the growth of more oxygenated ®lms. Finally, absorption of UV photons by adatoms could result in an increase of their surface mobility. All these factors have a bene®cial effect upon crystalline growth. # 2000 Elsevier Science B.V. All rights reserved