In this study, structural and electrical properties of Ag/TiO2/n-InP/Au Schottky barrier diodes, constructed with sputtering method on n-InP wafer, are investigated. Particle size, d- spacing, micro-strain, ideality factor and barrier heights of two samples are determined for two different interfacial TiO2 layer thickness. Thickness of TiO2 interfacial layers are adjusted as 60 angstrom and 120 angstrom. X-ray diffraction (XRD) and current-voltage (I-V) measurements are employed for mentioned parameters. It is seen that sample with 60 angstrom TiO2 interfacial layer is a more ideal diode. It is seen that as thickness of TiO2 interface decrease Ag/TiO2/n-InP Schottky diode becomes more ideal. This result is explained in main text in connection with series resistance, difference between d-spacings of interface and wafer. Comments on relation of lattice mismatch with series resistance are also made.