Investigation of RuTiN and RuTiO diffusion barrier suggested by a new design concept for future high-density memory capacitors

Abstract

As a new design concept for high-density memory capacitors, we proposed both RuTiN (RTN) and the RuTiO (RTO) materials as sacrificial oxygen diffusion barriers. The sheet resistance of the newly developed RuTiN and RuTiO barriers after oxidation was much lower than that of polycrystalline nitride and ternary amorphous barriers reported by others. For the Pt/barrier/TiSi/sub x//n/sup ++/poly-plug/n/sup +/ channel layer/Si contact structure, contact resistance was below 5 kohm even after annealing up to 750/spl deg/C. Correspondingly, the new RuTiN and RuTiO films, as diffusion barriers for oxygen, are very promising materials for high-density capacitors.