Direct measurement of the interfacial barrier height of the manganite p-n heterojunction

A manganite p-n heterojunction composed of La_0.67Sr_0.33MnO₃ film and 0.05 wt% Nb-doped SrTiO₃ substrate is fabricated. Rectifying behavior of the junction well described by the Shockley equation is observed, and the transport properties of the interface are experimentally studied. A satisfactorily logarithmic linear dependence of resistance on temperature is observed in a temperature range of 150 K-380 K, and the linear relation between bias and activation energies deduced from the R-1/T curves is observed. According to activation energy, the interfacial barrier of the heterojunction is obtained, which is 0.91 eV.