Patterning of Epitaxial Perovskites from Micro and Nano Molded Stencil Masks

• Published in: Advanced functional materials 2014-11, Vol.24 (43), p.6853-6861
• Main Authors: Nijland, Maarten, George, Antony, Thomas, Sean, Houwman, Evert P., Xia, Jing, Blank, Dave H. A., Rijnders, Guus, Koster, Gertjan, ten Elshof, Johan E.
• Format: Article
• Language: English
• Subjects: Crystal structure; Epitaxy; LSMO; Masks; metal oxide stencil masks; MiMiC; Molding (process); Nanostructure; Oxides; Perovskites; pulsed laser deposition; transfer molding; Zinc oxide
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201401170

A process is developed that combines soft lithographic molding with pulsed laser deposition (PLD) to make heteroepitaxial patterns of functional perovskite oxide materials. Micro‐ and nanostructures of sacrificial ZnO are made by micro molding in capillaries (MiMiC) and nano transfer molding, respectively, and used to screen the single crystalline substrates during subsequent PLD. ZnO is used because of its compatibility with the high temperatures reached during PLD and because of the ease of its removal after use by benefiting from its amphoteric nature. Sub‐micrometer sized lines of La0.67Sr0.33MnO3 are made by the transfer molding approach, preserving the anisotropic features expected for a fully oriented thin film and taking account for the magnetostatic contribution from the line shapes. Different patterns of SrRuO3 are made with lateral dimensions of a few micrometers having individual features for which electrical isolation is illustrated. The bottom‐up soft lithographic methods can be compliantly utilized for making epitaxial structures of various shapes and sizes in the μm down to the nm range, and offer unique opportunities for fundamental studies as well as for realizing technological applications. Nano transfer molding and micro molding in capillaries are used to make stencil masks of ZnO on single crystalline SrTiO3 substrates. Isolated epitaxial structures of two functional perovskite oxides are formed after pulsed laser deposition and dissolution of ZnO. Bottom‐up fabricated patterns similar to those presented here were not shown before, illustrating the versatility of the soft lithographic approaches.