Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Slide 1 Spezielle Anwendungen des VLSI – Entwurfs Applied VLSI design Phase 5 Reliability - Electromigration Robert Mars

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Metal wire Thickness fixed by process parameters Width can be adapted by designer Slide 2

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Metal reliability Slide 3

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Metal reliability Slide 4

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Electromigration Metal ions move towards the anode Force on ions due to electron scattering in direction of electron flow Electric field in metal causes electrostatic force on ions Damage caused by divergences in atomic flux Slide 5

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Enhancing reliability Wire Widening increasing cross-section area Passivation Layer prevent diffusion, better dissipation of joule heat Gold Metallizations very high activation energy Alloying of Metallization addition of Ti-Si or Cu to Al Deposition Techniques i.e. MTTF smaller for Sputtering than electron-beam deposition Wire length if wire is shorter than Blech length mechanical stress compensates material flow Slide 6

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Thank you for your attention Slide 7

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Quellen im-RA-wp.pdf Slide 8

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Stresses Slide 9

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock J max Calculation Quelle: Slide 10

Institute of Applied Microelectronics and Computer Engineering College of Computer Science and Electrical Engineering, University of Rostock Blech length Slide 11