基于多层烧结工艺的功率器件3D集成封装的关键技术（2024年4月）

集成陶瓷敷铜板、功率器件以及PCB板的3D集成封装可同时实现低杂散电感以及低热阻，同时可集成散热器、栅极驱动、解耦电容等元件。若采用传统的多级阶梯温度回流焊接工艺实现该封装中的多层连接层，模块的可靠性会显著降低；而且高压GaN HEMT器件表面极小的电极面积、间距也给封装带来了极大挑战。本工作提出基烧结工艺的封装方式，使每层连接层的工艺温度保持相同，同时利用柔性PCB板及精细烧结技术将高压GaN HEMT器件表面电极及间距扩大化，显著地提升了封装的可靠性。此外，模块信号输入端口应保持较低的阻抗以减小功率器件开关时带来的误动作，并通过仿真与测试互相辅助的方法来检测高集成3D封装中的器件开关特性。

The 3D-integrated packaging of integrated ceramic substrate, power devices, and PCB boards can simultaneously achieve low stray inductance and low thermal resistance, while also integrating components such as heatsink, gate driver, and decoupling capacitors. If the traditional multi-temperature reflow soldering processes is used to achieve multi-layer connections in this package, the reliability will be significantly reduced; Moreover, the extremely small electrodes area and spacing of high-voltage GaN HEMT devices pose great challenges to packaging. This work proposes a packaging method based on sintering technology, which maintains the same process temperature for each connecting layer. At the same time, flexible PCB boards and refined sintering technology are used to expand the surface electrodes and spacing of high-voltage GaN HEMT devices, significantly improving the reliability of packaging. In addition, the module signal input port should maintain a low impedance to reduce fault action caused by power device switching, and the device switching characteristics in high integration 3D packaging should be examined through simulation and testing methods together.