Ink-jet printing of SrTiO3 buffer layers from aqueous solutions

Abstract

In this work, fully alpha-axis oriented SrTiO3 thin films were synthesized by ink-jet printing of water-based precursor inks. The developed precursor solution or 'ink' was optimized in terms of rheology, leading to the ejection of single droplets showing a maximum contact angle of 12 degrees on (100) oriented single crystal LaAlO3 substrates. By using the appropriate ink-jet deposition parameters and thermal treatment, well-textured and dense SrTiO3 films of 130 nm thickness were obtained. The biaxial texture is maintained up to the surface of the films, leading to the formation of (h00)-oriented terraces. As shown by transmission electron microscopy, excellent texture transfer was achieved from the SrTiO3 film to the YBa2Cu3O7 - delta layer deposited by pulsed laser deposition. Outstanding superconducting properties were obtained with critical current densities up to 3.6 MA cm(-2) in self-field at 77 K, demonstrating that these sustainable SrTiO3 films meet the requirements to be used as growing template for high quality superconducting coatings