Title :
High-current failure model for VLSI interconnects under short-pulse stress conditions
Author :
Banerjee, K. ; Amerasekera, A. ; Cheung, N. ; Chenming Hu
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., California Univ., Berkeley, CA, USA
Abstract :
Short-time high joule heating causing thermal breakdown of metal interconnects in ESD/EOS protection circuits and I/O buffers has become a reliability concern. Such failures occur frequently during testing for latchup robustness and during ESD/EOS type events. In this work, heating and failure of passivated TiN/AlCu/TiN integrated circuit interconnects in a quadruple level metallization system of a sub-0.5 μm CMOS technology has been characterized under high-current pulse conditions. A model incorporating the heating of the layered metal system and the oxide surrounding it has been developed which relates the maximum allowable current density to the pulse width. The model is shown to be in excellent agreement with experimental results and is applied to generate design guidelines for ESD/EOS and I/O buffer interconnects.
Keywords :
CMOS integrated circuits; VLSI; aluminium alloys; copper alloys; current density; electrostatic discharge; failure analysis; integrated circuit interconnections; integrated circuit metallisation; integrated circuit modelling; integrated circuit reliability; protection; titanium compounds; 0.5 micron; CMOS technology; ESD/EOS protection circuits; I/O buffers; TiN-AlCu-TiN; VLSI interconnects; current density; high-current failure model; high-current pulse conditions; latchup robustness testing; metal IC interconnects; passivated TiN-AlCu-TiN interconnects; pulse width; quadruple level metallization system; reliability; short-pulse stress conditions; short-time high joule heating; thermal breakdown; CMOS technology; Earth Observing System; Electric breakdown; Electrostatic discharge; Heating; Integrated circuit interconnections; Protection; Semiconductor device modeling; Tin; Very large scale integration;
Journal_Title :
Electron Device Letters, IEEE