High-resolution temperature measurement of void dynamics induced by electromigration in aluminum metallization

The local temperature of aluminum metallization is measured directly during electromigration. High resolution thermography is used to detect void dynamics induced by a dc current. In the vicinity of the growing area, infrared radiation pulses less than 0.5 s wide are observed concomitant with resistance pulses. Their amplitudes are found to correspond to a temperature increase of more than 200 °C, which locally exceeds the melting point of aluminum metallization. These pulses occur as a consequence of void movement. Healing of voids is discussed along with the results.