Flip-chip assembly and 3D stacking of 1000V lateral IGBT (LIGBT) dies

10 A, 1000 V-rated lateral insulated-gate bipolar transistor (LIGBT) has been specifically developed for Implantable Cardioverter Defibrillators (ICDs) and its design optimised for flip-chip assembly. By replacing currently used vertical IGBT with a lateral design which has all terminals on the same side of the die, flip-chip technique could be used for assembly of all components of the ICD. This simplified and lowered the cost of the assembly and enabled advanced embedding and 3D PCB stacking for further product miniaturisation. The ICD product based on lateral IGBTs resulted in 30% smaller footprint and 4 times reduced height compared to existing solutions built with vertical high-voltage devices. Stacking of multiple PCBs assembled with LIGBTs has also been successfully demonstrated, resulting in 70% smaller product footprint compared to solutions based on vertical IGBTs. Moreover, lateral IGBTs have significantly lower leakage currents than vertical devices (>10x), which reduces power consumption during normal operation. This extends the battery life of defibrillators and increases intervals between replacement surgeries, benefitting both the patient and healthcare provider.