Title :
Investigation of sputtered TaCx and WCx films as diffusion barriers for Cu metallization
Author :
Tsai, Hao Yi ; Wang, Shui Jinn ; Sun, S.C.
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Abstract :
Physical and electrical properties as well as thermal stability of sputter-deposited TaCx and WCx films were investigated. The 60 nm-thick TaCx and WCx film shows a resistivity of around 385 μΩ-cm and 227 μΩ-cm, respectively. The allowable thermal stability of TaCx layer was found around 700°C which is about 50-100°C higher than that of WCx layer. It was found that the failure of the TaCx and WCx barrier layers is mainly attributed to the diffusion of Cu through the grain boundaries or localized defects of the barrier layers into Si substrate
Keywords :
annealing; chemical interdiffusion; copper; diffusion barriers; electrical resistivity; failure analysis; grain boundaries; integrated circuit metallisation; sputtered coatings; tantalum compounds; thermal stability; tungsten compounds; 227 muohmcm; 385 muohmcm; 60 nm; 700 C; Cu; Cu diffusion; Cu metallization; Si; Si substrate; TaC; WC; barrier layer failure; diffusion barriers; electrical properties; failure mechanisms; grain boundaries; localized defects; metal carbides; physical properties; resistivity; sputtered TaCx films; sputtered WCx films; thermal stability; Annealing; Bonding; Etching; Metallization; Optical wavelength conversion; Sputtering; Surface morphology; Surface treatment; Temperature; X-ray scattering;
Conference_Titel :
VLSI Technology, Systems, and Applications, 2001. Proceedings of Technical Papers. 2001 International Symposium on
Conference_Location :
Hsinchu
Print_ISBN :
0-7803-6412-0
DOI :
10.1109/VTSA.2001.934536
