An Introduction to Wire-Bondless Discrete GaN Power Packages With Top-Side Cu Sinterconnects®

Abstract

Power electronic modules have undergone a remarkable transition in terms of power density, temperature, and performance due to the shift from Si to WBG (Wide bandgap) semiconductors. WBG semiconductors with their high switching speed, high breakdown voltage and higher operation temperature outperform their Si counterparts. However, the current power packaging technologies are not sufficient to benefit from the superior properties of these WBG devices. For Si power electronic packaging, the traditional 500 μm Al wire bonding as top-side interconnection can carry a maximum current of 10 A which can be increased by parallel connections. However, the need for a higher current carrying capacity with a lower feature size is desirable for WBG devices. As a result, the conventional wire-bonding technology hinders these devices from reaching their full potential due to parasitics, heat dissipation, and reliability issues. To address these challenges, several wire bondless interconnection technologies have been proposed and developed. Among these technologies, a new alternative technology has been recently introduced by our group in which wire bonds are being replaced by printed Cu paste interconnects known as 'Cu sinterconnects®', So far, sinterconnects® have been only integrated into large IGBT power module packages where their efficiency has been proven. In this study, sinterconnects have been further optimized to be integrated into GaN-based discrete device discrete packages with fine feature sizes. The packaged GaN devices with fine-sinterconnects® were further characterized and compared with the standard wire-bonded GaN packages.