Mechanical stability of advanced nano-interconnects using pico-indentation

Metal interconnects handle power and signal distribution in electronic circuits between transistors and to the outside world.  To enable performance gains of circuits, the width of these interconnects needs to shrink to below 10nm in the coming decades. Besides, the material to separate lines from each other is only a few nm of … air.

Although such advanced nano-interconnects are awesome from an electrical point-of-view, their mechanical durability is heavily challenged. During processing and during/after packaging, interconnects need to withstand immense stresses in the order of a few 100 MPa and higher.

During this PhD, a so-called pico-indenter will be employed to study the mechanical behavior of these advanced interconnects. With such an indenter, one can locally (at the nm-scale!) apply high mechanical loads. By integrating this pico-indenter in advanced electron microscopes, motions can even be monitored and recorded in real time. This enables fascinating opportunities to visualize the collapse/failure of such nanostructures. Together with the recorded mechanical load, it can unravel the mystery behind this nano-scaled world and help improve the next generation of IC’s.

The main aim of the PhD is to understand the mechanical stability of these nano-interconnects and to predict the reliability behavior of these devices. This will be done by combining in-situ pico-indentation experiments on specially prepared test structures with advanced thermo-mechanical modelling techniques.

The supervisors of this PhD are world-recognized experts from both KU Leuven and imec in the field of nano-indentation and related thermo-mechanical modeling techniques.