AlCu- Metal Heater for Interconnect Monitoring Test Structures
Authors: Verena Hein and Marco Erstling Company: X-FAB Semiconductor Foundries AG Date Published: 1/25/2016
Pan Pacific Symposium
Abstract: Monitoring Wafer Level Reliability (WLR) tests are common to guarantee process stability and homogeneity. The test cost and test time efficiency are very important because of the high number of monitoring tests. Interconnects like metal lines and via structures are typically tested by higher temperatures on a thermo chuck because the possibilities for test acceleration are limited by Joule heating. Process Control Monitor (PCM) test systems with thermo chucks are more expensive and the time to reach stable chuck temperature extends the test time in addition. Typically poly silicon heaters are in use  but applications for interconnect test structures are limited. Interconnect layers could be far away from poly silicon in the metal stack. Self-heater structures have to be designed carefully because the additional metal environment could influence the mechanical properties of the test line as well as the lifetime .
Metal Heater, Self-Heating, Interconnect Monitoring, WLR Test Structure, Current Density Distribution