Reliability performance of different layouts of wide metal tracks

For industrial and automotive applications a 0.35μm aluminium CMOS process is one of the common used technologies. An increasing demand on extended operating conditions must be fulfilled especially for high current carrying metal lines. A new design concept is to modify the shape of these lines. The use of slots especially of octahedron slots demonstrates a better robustness towards electromigration in upper metallization layers. Another benefit is the good reliability under pulsed DC conditions primarily in comparison to wide homogeneous filled metal lines. In addition with slotted metal in all metallization layers stress due to thermal expansion can be reduced by keeping the lifetime at an adequate level. The performance of different layouts were investigated by electromigration tests and simulation to prepare basis knowledge for decision making process for design for higher robustness.