New type Schottky diodes based on the heterostructure of transition metal oxides: p-La2/3Sr1/3VO3/n-TiO2

Abstract

We make a new type of bipolar Schottky diodes using the p-type La2/3Sr1/3VO3 (LSVO)/n-TiO2 heterostructure. The p-type LSVO metal thin films are grown on various substrates using radio frequency magnetron co-sputtering deposition. We find that the LSVO film grown on anatase TiO2 layer produce the lowest resistivity of 0.28 mΩ cm. We discover that the resistivity decreases with decreasing LSVO film thickness for LSVO/TiO2/Si structures. Hall measurements are performed and the dielectric functions of LSVO films are measured. The effective mass of LSVO/TiO2/Si is determined to be 2.54 ± 0.05 m0. The current-voltage curves of the Schottky diodes of p-LSVO/n-TiO2 is measured and is explained using band alignment diagram. We identify a new type of Schottky diode, where both electrons in n-TiO2 and holes in p-LSVO can flow under bias.