Lateral interface effect on pulsed DC electromigration analysis

Abstract DC and Pulsed DC Electromigration tests at 1Hz and lOkHz have been performed on two single level Al-0.5%Cu metallizations. The Black's parameters have been analysed with a great confidence level using a statistical global approach. The results are in agreement with the Average Current Model at 10kHz and with the On-Time Model at 1Hz considering that thermal effects not only affect the current density exponent n, but also the duty cycle accelerating factor m. The extracted activation energies reflect the same diffusion mechanisms for the two metallizations. Microscopic observations showed huge metal accumulations for each structure and emphasized the influence of the resist stripping stage on the electromigration behaviour of the samples.