Keynote Lectures

suganuma Advances in WBG Power Device Packaging by Sinter Joining and Thermal Management
Katsuaki Suganuma

Osaka University

The market of new generation WBG power semiconductors has begun to bloom, including SiC and GaN. GaN is also expanding its market to high-power LEDs and to high-speed communications in post-5G. Since heat conduction, electrical conduction, and reliability of high-lead solder that have been used in the past are inferior, and since it cannot be used in the first place due to their durability and heat resistance in the temperature range exceeding 150 C, the appearance of new bonding materials is desired. Mass production of Ag sinter joined SiC devices with excellent characteristics has already started, and it is becoming a real technology. Although high pressure is still used in the market, since the sintering mechanism is understood, sufficient bonding characteristics have been obtained by low-pressure bonding using inexpensive particles of micron to submicron meter size at the stage of pursuing excellent cost performance. As Ag-sinter joining enables bonding in atmosphere, low pressure, large area, and dissimilar materials without any plating, it can be applied to high performance TIM for heat dissipation that enables an excellent heat dissipation structure. Now a day, the main battlefield for material development has expanded from Ag particle sintering to Cu particle sintering, but there are great expectations for Cu direct bonding not only to power semiconductors but also to advanced semiconductors. If one would understand that process handling of sinter joining is different from that of solders, he can obtain outstanding cost performance and reliability out of sinter joining technology. There is no doubt that the sintered joining technology is a new generation joining technology that replaces solders, and it is expected that its application field will expand further in the future.