Quality and Reliability of 3D TSV Interposer and Fine Pitch Solder Micro-bumps for 28nm Technology

摘要

Silicon interposer minimizes CTE mismatch between thechip and copper filled TSV interposer resulting in highreliability micro bumps. Furthermore, providing high wiringdensity interconnections and improved electrical performanceare the reasons TSV interposer has emerged as a goodsolution and getting significant industry attention.High density three dimensional (3D) interconnects formedby high aspect ratio through silicon via (TSV) and fine pitchsolder micro bumps are presented in this paper. Differentdesign/material related factors are evaluated during this studyin order to yield high aspect ratio void-free TSV copper viaand reliable micro-bumps. Quality and reliability of copperTSV and micro-bumps are monitored in-situ during theprocess. This paper presents some of the quality and reliabilityresults as well as micro-bump and TSV resistance data.Furthermore, bake and thermal-cycling measurements arepresented to insure reliability of the design and the materialselected for the 28nm technology TSV interposer FPGA.