Integration of low-k dielectrics for high performance 0.18 mu m interconnects

Interconnect performance, measured by RC delay, degrades rapidly as the dimensions of ULSI devices are scaled to the deep sub half micron region. While both low resistivity metals such as Cu and low capacitance dielectrics can be employed, this paper addresses the integration of low dielectric materials for capacitance reduction. A comparison of electrical results including line-to-line capacitance, leakage, and via performance for various low-k dielectrics including hydrogen silsesquioxane, airgap structures and xerogel are presented. Process integration complexity associated with various low-k dielectrics is also discussed.