Mechanical characterisation of ultra-thin chips

The mechanical characteristics of ultra-thin silicon chips fabricated using Chipfilm™ technology are presented. Obtaining a chip thickness down to 8 μm ± 0.2 μm these chips are particularly capable for future system-in-foil applications [3]. Due to their small thickness mechanical stress resulting from CMOS process layers affects both the warpage and the mechanical strength of the ultra-thin chips. Considering the additional requirements due to the small chip dimensions a three-point-bending set-up is used to investigate the mechanical stability of ultra-thin chips. Moreover, it is shown, that an additional silicon-oxide layer affects the mechanical stability positively, if tensile stress is applied.