SEMINAR: Engineering Interfaces To Improve Thermal Performance of Wide Bandgap Semiconductors

Abstract:

Wide bandgap electronics are currently under development due to their potential to create some of the most advanced RF and power electronics in the world. A key concern in their development is the control of the junction temperature during operation which is impacted by the internal device thermal resistance.  To address this concern, we will discuss advancements in thermal characterization techniques that have allowed new insights into the role of material interfaces on the thermal response of GaN and Ga2O3 electronic devices.  Recent advancements in growth have shown near theoretically high values of thermal conductivity for interfacial materials such as AlN, in excellent agreement with DFT calculations.  While such high thermal conductivity substrates like AlN, SiC or diamond have promise for heat dissipation from wide bandgap materials, their integration must be performed in a manner that limits the interfacial thermal resistance.  We will discuss methods of integration that include direct growth onto high thermal conductivity substrates as well as plasma activated bonding. Finally, for power electronics, packaging solutions for the thermal management of ultrawide bandgap devices will be presented, allowing for the future implementation of this technology.  

Bio:

Samuel Graham is the Eugene C. Gwaltney, Jr. Professor and Chair of the Woodruff School of Mechanical Engineering at the Georgia Institute of Technology.  He leads the Electronics Manufacturing and Reliability Laboratory which is focused on the electrical and thermal characterization, packaging, and reliability of wide bandgap semiconductors, solar cells, and flexible electronics.  He also holds a courtesy appointment in the School of Materials Science and Engineering at Georgia Tech, a joint appointment with Oak Ridge National Laboratory, and is a Visiting Professor at Nagoya University in Nagoya, Japan. He is a Fellow of ASME, a member of the Engineering Sciences Research Foundation Advisory Board of Sandia National Laboratories, Air Force Scientific Advisory Board, and the JASONs Advisory Group.