Crystallographic Effects on Nanoscale Electrical Properties of Ultrathin Lanthanum Aluminate Films

摘要

Thin LaAlO3 (LAO) films, 30 nm thick, were grown on Pt/Ti/SiO2/Si(100) and LaNiO3 (LNO)/Pt/Ti/SiO2/Si(100) substrates at 450-650 degrees C. LAO films that were grown on Pt substrates have amorphous features over a wide range of deposition temperatures. The growth of the LAO film with an LNO buffer promotes the appearance of highly (100) crystallographic features. The spatial distribution of the leakage current of LAO films on the nanometer scale indicates the substantially reduced nanostructural leakage current of LAO films on the buffering of LNO by an effective improvement in the film/electrode interface, chemical homogeneity, crystallinity, and surface roughness of the films.