One-Shot Excimer Laser Laminar Annealing of SrTiO3 Thin Films in Solidus Phase

By virtue of high optical absorptance and low thermal conductivity of SrTiO3, and short duration of the laser pulse, one-shot ArF excimer laser irradiation exerted an efficient annealing effect on the top SrTiO3 thin layer in the SrTiO3/YBa2Cu3O y /MgO heterostructure without causing interfacial deterioration. Namely, our new method is characterized by laminar annealing of nanosecond duration. Actually, by one-shot laser irradiation, the permittivity of the top SrTiO3 film (110 nm thick) was improved from 52ε 0 (as grown) to 220ε 0. Annealing strongly depended on the laser energy but not on the pulse number. When the laser energy was increased up to 150 mJ/cm2, at which the top surface of the underlying YBa2Cu3O y reached its molten phase, the SrTiO3 permittivity degraded markedlly.