Direct Defect-Level Analysis of Metal–Insulator–Metal Capacitor Using Internal Photoemission Spectroscopy

Barrier height (φ
_b
), trap state, bandgap ( E
_g
), and band alignment information of the metal-ZrO
₂
-metal capacitor have been extracted using internal photoemission (IPE) system. By correlating the IPE analysis with I-V and C-V characteristics obtained before and after rapid thermal annealing, origin and transformation of defect states have been successfully investigated. Our analysis revealed that deep-level defects originating from oxygen vacancies near the top electrode are causing of leakage current in MIM capacitor and these defects can be effectively reduced by a proper thermal annealing.