Physical and electrical characterization of high-k ZrO2 metal-insulator-metal capacitor

The effect of the deposition temperature and layer thickness on the physical and electrical properties of ZrO2-based high-k metal-insulator-metal (MIM) capacitors was studied. The increasing thickness of ZrO2 layer leads to decreasing the leakage current and capacitance of the device. The microstructure investigation shows that after the deposition of the complete MIM stack layer, all samples reveal similar degree of crystallinity, independent of the dielectric deposition temperature, hence it cannot explain completely the different electrical performance of the device. We found that the impurities concentration in the stack decreases as the deposition temperature increases. As a result, we obtain low leakage current (< 10− 8 A/cm2) with highest k value(~ 43) for 8 nm ZrO2 layer deposited at a temperature of 275 °C.