Temperature scaling of electromigration threshold product in Cu/low-K interconnects

Abstract

In this paper, we report on the temperature dependence of electromigration threshold product in copper interconnects. The electromigration threshold product (jL) c is first determined from lifetime distributions for temperatures ranging from 260°C to 330°C. We then propose an alternative method to determine (jL) c at much lower temperatures. We show that the threshold product does not vary significantly in the investigated temperature range. We demonstrate this alternative method is suitable to determine (jL) c close to the final product operating temperature, which would require unrealistic test duration if performed with a conventional method based on lifetime data.

Study on the effectiveness of reservoir length in improving electromigration in Cu/Low-k interconnects

“…With decreasing Ta barrier thickness, the product is also found to be smaller because of the reducing confinement [24]. Besides, the threshold product is also found to depend on the temperature of Cu interconnects [25] in the range of 260 0 C -330 0 C.…”

“…25 shows the the value of the distance/AFD max which is proportional to the MTF of an interconnect as we have established earlier. Here we only consider Term 2 impact…”