Pulsed laser deposition of SrTiO3 on InP and integration of ferro-piezo-electric Pb0.775La0.15TiO3

SrTiO3 (STO) has been deposited on (1 0 0)InP substrates by laser ablation to propitiate the integration of La-modified PbTiO3 (PLT). The optimum conditions found for STO deposition using a KrF excimer laser were laser fluence J=4 J/cm2, oxygen pressure PO2=10−3 mbar and a substrate temperature Ts=580–630 °C. The STO films so obtained show [1 0 0]-texture and low roughness, σ≈0.8% of the layer thickness. [0 0 1+1 0 0]-textured Pb0.775La0.15TiO3 films with a uniform composition close to the target one and σ≈2% of layer thickness were obtained on these STO buffers. The analysis of the STO surface properties under the scaling theory framework suggests an efficient surface diffusion of the arriving species as the origin of the low roughness.