Characterization of 3D interconnections buried in the silicon by the generation of electrical pulses in a photoswitch. – CIBON

The 3D stacking of chips in microelectronics is a solution that allows more compact system integration and higher frequency signals propagation. This project aims at characterizing interconnections buried in the stack of silicon chips by optoelectronic means. Conventional electrical characterizations based on probe contact measurements require complex de-embedding and several measurement setups. The proposed solution is based on the no-contact generation of an electrical pulse in silicon photoswitches illuminated by a femtosecond laser excitation. This pulse will be propagated along a full interconnection, thus allowing its characterization. The challenge of this project is to realized photoswitches compatible with industrial silicon technologies; the ultimate objective is achieving frequency characterization up to several hundred GHz.