Methodology for an assessment of the degree of barrier permeability at via bottom during electromigration using dissimilar barrier thickness

A system for assessing a magnitude of a barrier permeability at a via bottom during electromigration, comprising:

• a test structure, comprising:
• a first conductor;
• a second conductor, wherein the second conductor forms an interconnect;
• a no-flux barrier disposed between the first and second conductor, wherein the no-flux barrier is substantially impermeable to mass flux;
• a third conductor;
• and
• a test barrier disposed between the second and third conductor, wherein the test barrier is to be assessed for the magnitude of barrier permeability;
• a current source operable to conduct a current through the test structure;
• a timer operable to measure a lifetime of the test structure;
• and
• a processor for determining a permeability of the test barrier based on the measured lifetime of the test structure.

A method of determining a barrier permeability, comprising:

• forming a test structure having a test barrier between a first conductor and a second conductor;
• conducting a current through the test structure;
• measuring a lifetime of the test structure;
• and
• assigning a barrier permeability value to the test barrier based on the measured lifetime.