A design for highly robust ALCU-W-PLUG-metallization stack

Abstract

Mission profiles for semiconductor applications are getting more and more challenging regarding electrical and thermomechanical robustness of metallization stacks. Effects, especially in thick metals, were investigated over the last years to find solutions for an improvement regarding both potential stressors. Some elements of a metallization were designed, investigated and simulated [1, 2, 3, 4 5]. But for an implementation in products it is necessary to develop a complete metallization stack. Therefore a support for layout tools is indispensable. This paper will explain the principles of a highly robust AlCu-metallization stack, the physics and failure mechanisms which are considered for some elements of such a metal stack and the design solution.