Glass for Encapsulating High-Temperature Power Modules
Glass for Encapsulating High-Temperature Power Modules
复制标题
用于封装高温功率模块的玻璃
DOI：
10.1109/jestpe.2020.3004021
复制
发表时间：
2021
影响因子：
5.5
通讯作者：
G. Lu
中科院分区：
文献类型：
--
作者：
Lanbing Liu;David Nam;Ben Guo;J. Ewanchuk;R. Burgos;G. Lu
由于热降解，传统的聚合物或有机密封剂不能在高温(>；250°C)下长期运行。在这项工作中，我们评估了一种无机材料，即低熔点(TMelt<；500°C)铅玻璃，作为一种潜在的碳化硅功率模块高温封装剂。研究了在Al_2O_3直接结合铜(DBC)基板上加工玻璃的工艺，并设计了一种应力消除方案来解决热应力导致的玻璃开裂问题。通过测量局部放电起始电压(PDIV)来表征玻璃的电绝缘性能。玻璃封装的测试片在250°C的温度下，在1 mm的间隙上的平均PDIV为>；3kv。玻璃封装的1kv，36A的SiCMOSFET表现出正常的静态和动态特性，这表明玻璃在加工过程中不会对SiC器件造成损害。至于可靠性，玻璃密封剂比几种高温聚合物密封剂(额定温度>；300°C)在250°C下浸泡的时间要长得多。
Conventional polymeric or organic encapsulants cannot survive long-term operation at high temperatures (>250 °C) due to their thermal degradation. In this work, we evaluated an inorganic material, i.e., a low-melting-point (Tmelt < 500 °C) lead glass, as a potential high-temperature encapsulant for SiC power modules. Processing of the glass on an Al2O3 direct-bond-copper (DBC) substrate was studied, and a stress-relief solution was devised to solve the thermal-stress-induced glass cracking. The electrical insulation capability of the glass was characterized by measuring partial discharge inception voltage (PDIV). The average PDIV of the glass-encapsulated test coupons across a 1-mm gap was >3 kV at temperatures up to 250 °C. The glass-encapsulated 1-kV, 36-A SiC MOSFETs showed normal static and dynamic characteristics, suggesting that the glass did not cause damages to the SiC devices during processing. As for reliability, the glass encapsulant survived a much longer time than several high-temperature polymeric encapsulants (rated temperature > 300 °C) soaked at 250 °C.