Rapid thermal annealing influences on microstructure and electrical properties of Mo/ZrO₂/n-Si/Al MISM junction with a high-k ZrO₂ insulating layer

The microstructural, chemical and electrical properties of Mo/ZrO₂/n-Si/Al metal/insulator/semiconductor/metal (MISM) heterostructure with zirconium oxide (ZrO₂) as an insulating layer are investigated. In comparison to the metal/semiconductor/metal (MSM) structure, the as-deposited and 600 °C annealed MISM heterostructures demonstrate outstanding rectifying performance and extremely low reverse leakage current. The as-deposited (0.98 eV) and 600 °C annealed MISM heterostructures (1.12 eV) have a higher barrier height (ɸ_b) than the MSM structure (0.70 eV), which indicates that the barrier height is influenced by the ZrO₂ insulating layer. The results show that the ɸ_b values are improved for 600 °C annealed heterostructure. The forward bias C–V and G/w-V graphs exhibit anomalous peak/variations and three distinct regions called accumulation, depletion, and inversions with respect to the frequency that are attributed to the interface states and R_S. The results indicate that ZrO₂ film is an effective high-k oxide for the preparation of novel electronic device applications.