Material‑Dependent DLS Behavior of Cu‑Void Defects: An Integrated Electrical and Physical Failure Analysis
Material‑Dependent DLS Behavior of Cu‑Void Defects: An Integrated Electrical and Physical Failure Analysis
Tuesday, October 6, 2026: 12:50 PM
Summary:
Dynamic Laser Stimulation (DLS) is widely used for fault localization in advanced semiconductor devices by inducing localized thermal modulation during test execution. This work demonstrates that DLS can provide not only two-dimensional localization but also insight into the defective interconnect layer by analyzing the direction and conditions of Pass/Fail (P/F) transitions. We investigated a temperature-sensitive marginal failure exhibiting a Fail-to-Pass (F→P) transition under DLS, using an integrated approach combining logic diagnosis, FV-shmoo analysis, nanoprobing, EBAC, and cross-sectional STEM–EDS. Electrical characterization revealed a high-resistance interconnect defect whose resistance decreased with increasing temperature. Physical analysis identified a Cu-void defect containing Mn within the interconnect, suggesting the formation of a Mn-rich conductive phase with a negative temperature coefficient of resistance. This material-dependent behavior explains the observed F→P transition under localized laser heating. The results indicate that DLS response polarity (F→P versus P→F) is strongly influenced by defect material properties and interconnect layer composition. By leveraging this behavior, DLS can be extended from lateral fault localization to defective-layer estimation, significantly improving analysis efficiency for complex multi-layer interconnect structures in advanced technology nodes.
Dynamic Laser Stimulation (DLS) is widely used for fault localization in advanced semiconductor devices by inducing localized thermal modulation during test execution. This work demonstrates that DLS can provide not only two-dimensional localization but also insight into the defective interconnect layer by analyzing the direction and conditions of Pass/Fail (P/F) transitions. We investigated a temperature-sensitive marginal failure exhibiting a Fail-to-Pass (F→P) transition under DLS, using an integrated approach combining logic diagnosis, FV-shmoo analysis, nanoprobing, EBAC, and cross-sectional STEM–EDS. Electrical characterization revealed a high-resistance interconnect defect whose resistance decreased with increasing temperature. Physical analysis identified a Cu-void defect containing Mn within the interconnect, suggesting the formation of a Mn-rich conductive phase with a negative temperature coefficient of resistance. This material-dependent behavior explains the observed F→P transition under localized laser heating. The results indicate that DLS response polarity (F→P versus P→F) is strongly influenced by defect material properties and interconnect layer composition. By leveraging this behavior, DLS can be extended from lateral fault localization to defective-layer estimation, significantly improving analysis efficiency for complex multi-layer interconnect structures in advanced technology nodes.