TSV Redundancy: Architecture and Design Issues in 3-D IC

3-D technology provides many benefits including high density, high bandwidth, low-power, and small form-factor. Through Silicon Via (TSV), which provides communication links for dies in vertical direction, is a critical design issue in 3-D integration. Just like other components, the fabrication and bonding of TSVs can fail. A failed TSV can severely increase the cost and decrease the yield as the number of dies to be stacked increases. A redundant TSV architecture with reasonable cost is proposed in this paper. Based on probabilistic models, some interesting findings are reported. First, the number of failed TSVs in a tier is usually less than 2 when the number of TSVs in a tier is less than 1000 and less than 5 when the number of TSVs in a tier is less than 10000. Assuming that there are at most 2-5 failed TSVs in a tier. With one redundant TSV allocated to one TSV block, our proposed structure leads to 90% and 95% recovery rates for TSV blocks of size 50 and 25, respectively. Finally, analysis on overall yield shows that the proposed design can successfully recover most of the failed chips and increase the yield of TSV to 99.4%.