Contact Resistance Anomalies of Vias before Breakdown in Accelerated Current Life Tests

To test a new method for reliability assessment a two via test structure was designed including standard 4-point contact pads for current supply and voltage measurement and additional intermediate contact pads allowing observation of voltage drop along lines and vias. Under special conditions the tests showed heavy anomalies of voltage drop between the intermediate contacts which are attributed to void development within the contact layers. © 1999 Elsevier Science Ltd. Ail rights reserved.