Imaging of crack nucleation and propagation at the Si–metal interface on 3D printed micropillars

We aim to use X-ray microtomography to investigate the cracking mechanisms arising from thermal cycling (77 K – 370 K) in hybrid micro-pillar structures fabricated via laser powder bed fusion for high-performance thermal management in electronic devices. The integration of a Sn-based thermal interface and Al-based pillars on monocrystalline silicon substrates presents potential reliability concerns due to thermal expansion mismatch and residual stresses. High-resolution synchrotron X-ray tomography will enable non-destructive, in situ and ex situ imaging of eventual crack nucleation and propagation at the Si–Sn interface under various thermal conditions. We will extend the investigation to hybrid pillars made of alternative materials such as Ni-Ti, Ti- and Cu-based alloys. We aim to assess the influence of pillar material on interfacial cracking and overall thermal reliability. The findings will support the development of robust thermal architectures for space electronics.