Thermal Management of Gallium Nitride Electronics

Electronic device performance has always been restricted by the heat generated during operation. Thermal management employed in mass-produced electronics has not been able to provide a high thermal conductivity path close to the heat generation source in a wide bandgap semiconductor device such as the Gallium Nitride high electron mobility transistor.

Over the past 10 years, the authors have performed pioneering experiments in the integration of nanocrystalline diamond capping layers into the fabrication process of compound semiconductor devices. Significant research efforts of integrating diamond and GaN have been reported by a number of groups since then, resulting in active thermal management options that do not necessarily lead to performance derating to avoid self-heating during radio frequency or power switching operation of these devices. Self-heating refers to the increased channel temperature caused by increased energy transfer from electrons to the lattice at high power. A number of research programs have attempted to solve this problem and bring integrated diamond heat spreaders into the world of mass-produced microelectronics.

This book outlines the technical approaches undertaken by leaders in the community, as well as the challenges they have faced and the resulting advances in the field. The purpose of this book is to serve as a one-stop reference for compound semiconductor device researchers tasked with solving this engineering challenge for future material systems based on ultra-wide bandgap semiconductors. A number of perspectives are included such as; the growth methods of nanocrystalline diamond, the materials integration of polycrystalline diamond through wafer bonding, and the new physics of thermal transport across heterogeneous interfaces. The inclusion of all these aspects of diamond thermal management will help enable researchers to make the translation from the lab to the market.