Title :
Evaluation of amorphous (Ta,W,Mo)-Si-N diffusion barriers between Cu and Si
Author :
Sun, S.C. ; Yap, H.K. ; Chen, C.A. ; Lin, P.
Author_Institution :
ProMOS Technol., Hsinchu, Taiwan
Abstract :
This paper reports the investigation of sputtered Ta-Si-N, W-Si-N, and Mo-Si-N thin films as diffusion barriers for copper interconnects. The thermal stability of the barriers generally improves with increasing nitrogen concentration in the films, with the drawback of an increase in the film´s resistivity. The stability reaches a peak value and then decreases with excessive amounts of nitrogen. This change of barrier property is attributed to the dependence of film´s microstructure on the nitrogen content. Diode leakage current measurements indicate that Mo-Si-N has a lower resistivity and a higher thermal stability as compared to Ta-Si-N and W-Si-N
Keywords :
amorphous state; diffusion barriers; electrical resistivity; integrated circuit interconnections; integrated circuit metallisation; leakage currents; molybdenum; nitrogen; silicon; sputtered coatings; tantalum; thermal stability; tungsten; Cu interconnects; Cu-Si; Mo-Si-N; Ta-Si-N; W-Si-N; amorphous diffusion barriers; diode leakage current measurements; microstructure; resistivity; sputtered Mo-Si-N films; sputtered Ta-Si-N films; sputtered W-Si-N films; thermal stability; Amorphous materials; Conductivity; Copper; Diodes; Leakage current; Microstructure; Nitrogen; Sputtering; Thermal resistance; Thermal stability;
Conference_Titel :
Solid-State and Integrated-Circuit Technology, 2001. Proceedings. 6th International Conference on
Conference_Location :
Shanghai
Print_ISBN :
0-7803-6520-8
DOI :
10.1109/ICSICT.2001.981503
