中文摘要：

电力半导体器件的散热性能和热可靠性与其封装结构密切相关，选择合适的封装结构对改善器件的散热性能和提高热可靠性非常重要。文中根据压接式GCT器件封装结构特点，采用ANSYS软件利用有限元法分析了单芯片封装和多芯片封装结构的温度及热机械应力分布，并与常规的焊接式封装进行了对比。结果表明，压接式封装结构的散热效果比焊接式封装结构稍差。但其芯片上产生的热机械应力明显减小。多芯片封装采用常规的风冷散热器时芯片温度已经超过了器件的安全工作温度（125℃），应该采用热管散热器才能保证器件可靠地工作。

英文摘要：

The thermal dissipation and reliability of power semiconductor devices are related closely to packaging structure. Suitable packaging structure is chosen which is important to im- prove performance and reliability. In this paper, based on the structural features of the press- pack GCT packaging, its thermal characteristics of single-chip and multi-chip packaging are ana- lyzed by FEM（Finite element method） and compared with that of conventional welding packag- ing. The results show that thermal dissipation of the press-pack packaging is poorer, while ther- too-mechanical stress on chip is smaller comparing with welding packaging. And a heatpipe heatsink is necessary to fulfill the requirements of thermal dissipation for multichip packaging with conventional air cooling heatsink as the chip operating temperature has exceeded safe operat- ing temperature 125℃.