Failure in metallization systems

Abstract

<P>WITH THE INCREASING NEED FOR BETTER CONDUCTIVITY MATERIAL FOR THE TRANSISTOR BACK-END INTERCONNECT SYSTEM, THE INDUSTRY HAS SWITCHED TO COPPER AS THE METAL OF CHOICE. THE PRESENT WORK INVESTIGATES THE VARIOUS IMPLICATIONS OF IMPLEMENTING COPPER IN THE BACKEND INTERCONNECT SYSTEM OF A MICROCHIP. QUANTIFICATION OF ADHESION STRENGTH OF DIFFUSION FILMS TO DIELECTRIC HAVE BEEN DONE BY A NOVEL METHOD KNOWN AS MODIFIED EDGE LIFT-OFF TEST (MELT) AND SURFACED ANALYZED BY X-RAY PHOTOELECTRON SPECTROSCOPY. THE ORIENTATIONS OF CU AND TA FILM DEPOSITED ON TAN SUBSTRATE AS WELL AS THE EFFECTS OF N2 FLOW RATE ON ITS FILM STRUCTURE AND COMPOSITION HAVE BEEN ANALYZED BY GLANCING ANGLE X-RAY DIFFRACTION AND AUGER ELECTRON SPECTROSCOPY STUDIES. LASTLY, THE COMMON PROBLEM OF STRESS MIGRATION ISSUES HAVE BEEN FURTHER INVESTIGATED BY A SERIES OF HEAT STRESSING EXPERIMENTS ON TEST STRUCTURES (KELVIN AND CHAIN VIA STRUCTURES) AND ANALYSIS TECHNIQUES USING PASSIVE VOLTAGE CONTRAST, CROSS-SECTIONING BY TRANS