Power devices on bulk gallium nitride substrates: An overview of ARPA-E's SWITCHES program

Wide bandgap power semiconductor devices offer substantial energy efficiency opportunities in a wide range of applications. However, to date, relatively high cost has impeded the widespread adoption of these devices in many high volume applications. Recent progress in high quality bulk GaN substrates offers a new potential pathway to the development of novel vertical power semiconductor devices in gallium nitride. If successfully developed, these devices could offer a pathway to functional cost parity with silicon-based power devices at higher power levels. The Advanced Research Projects Agency-Energy (ARPA-E)'s recently launched SWITCHES program is targeting the development of bulk GaN, 1200 V, 100 A transistors and diodes. In this paper, we give an overview of the technical approaches within the program and discuss some of the major anticipated challenges.