Impact of TiN Plasma Post-treatment on Alumina Electron Trapping

Three-dimensional architecture appears today to be essential for the next high density MIM capacitor generation. Thus, the classical PVD method usually used for the electrode deposition must be replaced by conformal deposition methods, like CVD method. In this paper, trapping phenomenon of metal-insulator-metal capacitors using CVD-TiN for electrodes and ALD-Al₂O₃ for insulator is studied. In particular, we demonstrate the correlation between the plasma post-treatment applied to the CVD-TiN layer to ensure its low resistivity and the charge trapping in alumina. Moreover while applying the Di Maria method to those MIM structures, we demonstrate that charges trapped are electrons, located near the metal/insulator interfaces. Finally, we propose an explanation of the physical origin of this trapping phenomenon, based on former work