The electrical properties for the new RuTiN barrier material were investigated and compared with those for a TiN barrier. In case of the TiN barrier in the sputtered-(Ba,Sr)TiO3 simple stack-type structure, the TiN film was partially oxidized in the as-deposited state and was almost completely oxidized at 550C, leading to a degradation of the capacitance. In contrast, the new RuTiN barrier was not oxidized up to 600C, and exhibited an improved capacitance of >30fF/cell, although the leakage current was very high (~10-9A/cell) due to low work function (4.43eV). Correspondingly, the diffusion barrier performance of new RuTiN film, as an O diffusion barrier for high-density volatile capacitor, was better than that of the TiN barrier.

Diffusion Barrier Performance of Novel RuTiN Material for High-Density Volatile Memory Capacitor. D.S.Yoon, J.S.Roh, S.M.Lee, H.K.Baik: Acta Materialia, 2003, 51[9], 2531-8