Laser drilling and thermal stress analysis on TSV in 3D IC structure

Abstract

3D IC technologies are now approaching the innovation and business activities of semiconductor industries. 3D IC can be heterogeneous from different chip, interposer or substrate to integrate into a single package by using through silicon via (TSV) technique. With increasing functionality and performance at minimum cost and power dissipation, wide I/O memory VLSI technologies are being aggressively scaled to meet this demand. Stack memory chips using TSV technique will lead to increase a significant manufacturing challenge for semiconductor industries. TSV formation and interconnected reliability on the intermetallic compound (IMC) between the metal-metal bounded micro-bumps are crucial for 3D IC technologies. As the number and power of IC increases, lots of heat will be generated and, in turn raises the junction temperature. This will greatly deteriorate the performance of IC. Heat dissipation for 3D IC, when the power density exceeds 100W/cm2, is an important design concern before marketing. In this paper, high density TSV formed by an ultrafast pico-second laser to evaluate the behavior between manufacturing process and silicon material is presented. In addition, thermal management using finite element analysis to predict the reliability of TSV model is demonstrated.