Chemical states and electrical features of Ti/CaTiO₃ (CT)/p-InP MIS-type Schottky diode with a high-k CT interlayer

The work was mainly concentrated on the fabrication of the Ti/CaTiO3 (CT)/p-InP MIS-type diode with a CT interlayer and explored its surface topology, structural and chemical features using AFM, XRD and XPS procedures. XRD and XPS analysis exposes that the CT layer was formed on the InP surface. The electrical properties of the MIS diode and Ti/p-InP Schottky diode (SD) were performed using I-V and C-V procedures. A better rectification nature was obtained for the MIS diode over the SD. A larger barrier height (BH) was obtained for the MIS diode (0.84 eV) compared to the SD (0.72 eV), indicating the CT layer affects the BH of the SD. The BH was extracted using I-V, Cheung's function and alpha(V)-V graph, and the values are comparable, indicating their steadiness and validity. Reduced density of states (NSS) was achieved for the MIS diode than the SD, signifying that the CT layer diminished the NSS value. Results show that the CT interlayer is a potential high-k material for making MIS/MOS devices.