Title :
CoTiO3 high-κ dielectrics on HSG for DRAM applications
Author :
Chao, Tien-Sheng ; Ku, Wei-Ming ; Lin, Hong-Chin ; Landheer, Dolf ; Wang, Yu-Yang ; Mori, Yukihiro
Author_Institution :
Dept. of Electrophys., Nat. Chiao-Tung Univ., Hsinchu, Taiwan
Abstract :
In this paper, a new high-κ dielectric CoTiO3 has been investigated for the first time on hemispherical grained (HSG) poly-Si dynamic random access memories capacitors. Three types of HSG were prepared. We found that capacitors with maximum grain size and the highest density exhibit twice the capacitance of the others. The dielectric constant for CoTiO3 was estimated to be larger than 50. Leakage current measurements performed at temperatures as high as 100°C show that this dielectric is stable. The polarity dependence is found to be due to the different barrier heights with the nitride barrier. A leakage mechanism is proposed for this polarity dependence.
Keywords :
DRAM chips; capacitance; capacitors; cobalt compounds; dielectric materials; leakage currents; 100 C; CoTiO3; DRAM applications; dielectric constant; grain size; hemispherical grained random access memories capacitors; high-k dielectrics; leakage current measurements; poly-Si dynamic random access memories capacitors; Capacitance; Capacitors; Current measurement; DRAM chips; Dielectric constant; Dielectric measurements; Grain size; Leakage current; Performance evaluation; Temperature measurement; 65; DRAM; Dynamic random access memories; high-; nitride;
Journal_Title :
Electron Devices, IEEE Transactions on
DOI :
10.1109/TED.2004.839880
