Study of the resistive switching effect in In/HfO2/Ptdevices

HfO2 thin films were grown on Pt/TiO2/SiO2/Si substrates via RF magnetron sputtering technique at pure oxygen atmosphere with a substrate temperature of 550 °C. We studied the structural and electrical properties on HfO2 thin films, varying the thickness (tHfO2) from 23 to 155 nm. Grazing-incident x-ray diffraction shows a polycrystalline composition, some peaks are shifted when the tHfO2 increase, that is, a relaxation occur on the film. We fabricated In/HfO2/Ptlike a capacitor structurefor perform the electrical property measurements. The current-voltage curves display a resistive switching behavior for all thicknesses, and the resistance dependence with time, displays retention states with Low and High resistance in all samples. The percentage of change on resistance ([(RON-ROFF)/ROFF]×100) scale with HfO2 thickness and reach a saturation value ∼ 30% at tHfO2>120 nm.