The need for multi-scale approaches in Cu/low-k reliability issues

Since recent years, micro-electronic industry changed the basic materials from Al/SiO2 to Cu/low-k in IC interconnect structure. As a consequence, new reliability issues at device/product level has been discovered, and most of the failure modes have the characteristics of multi-scale: the failure of the μm or nm induces the malfunction of the device/product. Under the pressure of the time-to-market, the industries, universities and research institutes developed numerous multi-scale simulation technologies/tools to analyze the failure mechanism and to achieve the high reliability design with the capability of high volume production and low cost. This paper reviews the multi-scale modeling techniques for reliability and processing issues in Cu/low-k IC back-end structure, from the continuum level to the atomic scale.