Conduction Mechanism and Reliability Characteristics of a Metal-Insulator-Metal Capacitor with Single ZrO2 Layer

In this paper, the electrical characteristics and reliability of ZrO2-based metal-insulator-metal (MIM) capacitors are investigated. High capacitance density of 15.3 fF/mu m(2) was achieved for ZrO2 MIM capacitors, which is acceptable for the reported MIM capacitors. Schottky emission at the low field region is not a dominant mechanism, and Frenkel-Poole emission is the dominant mechanism at the high electric field region. The extracted dynamic constant and trap energy level were 4.013 and 0.963 eV, respectively. The reduced trap energy level with increasing electric field is due to a rise in the field-induced barrier-lowering effect. The variation of alpha as a function of stress time under constant voltage stress (CVS) gradually decreases, while the variation of Delta C-stress/C-0 under CVS increases because the generation of new dipoles in the high-kappa dielectric under CVS may cause charge trapping in the high-kappa dielectric. (C) 2011 The Japan Society of Applied Physics