First assemblies using Deep Trench Termination diodes

In this paper, diodes manufactured in 2008, allowing to obtain the first electrical measurements of the Deep Trench Termination (DT²), are analyzed in a reliability purpose. For the first time, assemblies are made using DT² diodes reported on Direct Bonded Copper (DBC) substrates using silver sintering process in order to confirm the possibility to integrate this technology in future lead-free packaging. Indeed, geometric singularities and different mechanical properties of BenzoCycloButen (BCB) and silicon could weaken the chip. In order to confirm the device electrical stability, passive thermal ageing are achieved. Then, breakdown voltage measurements, optical observations and TCAD-SENTAURUS simulations are investigated in order to provide explanation of the induced phenomenon linked to the aging.