Identification And Layout Modification Of Copper/Low K Interconnect Dielectric Reliability Assessment By Using Rvdb Test

Wafer-level ramped voltage to dielectric breakdown testing (RVDB) on copper/low k interconnect dielectrics has been used for reliability assessment and is motivated by practical needs for shortened test cycle time and large sampling for accurate statistical characterization. This work has identified a meaningful correlation between RVDB and TDDB (time dependent dielectric breakdown), which demonstrates the capabilities of RVDB for reasonable lifetime projection. Further analysis using the finite element method (FEM) has shown that layout modification is necessary to eliminate the impact of field enhancements at the metal line-end. RVDB and TDDB testing on such modified structures characterize well the intrinsic reliability behavior of interconnect dielectrics.