Title :
Modeling electromigration failures in TiN/Al-alloy/TiN interconnects and TiN thin films
Author :
Tao, Jiang ; Cheung, N.W. ; Hu, C.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., California Univ., Berkeley, CA, USA
Abstract :
Electromigration characteristics, especially resistance oscillations, of TiN/Al-alloy/TiN multilayered interconnect and the failure mechanism of a TiN barrier layer have been studied. A model has been developed for the linewidth dependence of the multilayered structure. The experimental results show that the failure observed in TiN was not caused by electromigration, instead it was due to thermomigration caused by a temperature gradient. The activation energy of this process was found to be 1.5 eV. In order to obtain a 10-year lifetime, the hottest spot in the TiN film must be kept below 408/spl deg/C. This suggests that TiN may safely conduct 2.4/spl times/10/sup 7/ A/cm/sup 2/ for the typical thermal impedance of a hot spot.
Keywords :
aluminium alloys; electromigration; failure analysis; integrated circuit interconnections; integrated circuit metallisation; integrated circuit reliability; reliability theory; semiconductor process modelling; silicon alloys; temperature distribution; titanium compounds; 10 year; 408 C; TiN barrier layer; TiN-AlSi-TiN; TiN/Al-alloy/TiN interconnects; activation energy; electromigration failure modeling; failure mechanism; hot spot; lifetime; linewidth dependence; multilayered interconnect; resistance oscillations; temperature gradient; thermal impedance; thermomigration; Conducting materials; Current density; Electric resistance; Electromigration; Integrated circuit interconnections; Temperature; Thermal resistance; Thermal stresses; Tin; Transistors;
Conference_Titel :
Reliability Physics Symposium, 1995. 33rd Annual Proceedings., IEEE International
Conference_Location :
Las Vegas, NV
Print_ISBN :
0-7803-2031-X
DOI :
10.1109/RELPHY.1995.513705
