Qualcomm's Nowak: 3-D Faces Cost Issues

摘要

3-D interconnects face plenty of issues that must be dealt with before the benefits of the approach can be realized, said Matt Nowak, director of advanced technology for Qualcomm Inc. (San Diego), in a plenary speech at the IEEE 3-D IC conference in San Francisco last month.rnNowak said through-silicon via (TSV) development and characterization needs to move to leading-edge CMOS, containing strained transistors, ultralow-k dielectrics, and thin die. Other issues include a lack of standard process flows, unproven yield/reliability, and an unclear supply-chain handoff.rnMobile wireless devices need low-cost solutions that improve power efficiency while enhancing performance in terms of bandwidth/milliwatt. Qualcomm now relies on stacked bare die using wire bond and flip-chip, and Nowak said 3-D TSV technology would enable "new architectural solutions that can only be realized with such high-density tier-to-tier connections."