A Study on Zirconium Oxide High-K Dielectric Nano-Films in Metal-Insulator-Metal Capacitors Configuration for Future Analog/Mixed-Signal Device Applications
摘要
This study reports fabrication of zirconium oxide (ZrO2) nano-films on aluminum-coated silicon substrates in a modified dense plasma focus device. The nano-films are found to be amorphous, ~ 20 nm thick, have standard stoichiometry and possess nanostructured morphology with low surface roughness. These nano-films are used to fabricate the actual metal-insulator-metal (MIM) capacitors and their electrical characteristics were studied both for as-deposited and after post-metallic annealing (PMA). The as-deposited MIM capacitors possess low leakage current density of ~ 1.08 × 10−10 A/cm2 at − 1 V, high capacitance density of ~ 19.89 fF/μm2 at 0 V, 1 MHz and improved quadratic voltage coefficient of capacitance (VCC) of ~ 185 ppm/V2 at 1 MHz. An enhancement in these electrical properties has been observed for PMA MIM capacitors with leakage current density of ~ 4.27 × 10−12 A/cm2 at − 1 V, capacitance density of ~ 24.43 fF/μm2 at 0 V, 1 MHz and better quadratic VCC of ~ 87 ppm/V2 at 1 MHz. The obtained results are much improved as compared to that reported in the literature and are in accordance with International Technology Roadmap for Semiconductor 2022 guidelines. The enhancement in the electrical properties of the presented MIM capacitors renders them as a potential candidate for future analog/mixed-signal devices applications.