Optically-Controlled GaN Power Devices
Abstract
This project focuses on the fundamental research needed to develop optically-controlled GaN and AlGaN power devices. These new switc,hes could overcome important hurdles in existing power electronic systems. For example, typical medium voltage power applications re,quire stacking of multiple devices to reach the desired blocking voltages and need complex circuitry to isolate the low-voltage gate, control electronics from the high-voltage bus. Optically-controlled devices will enable simplified and more compact power systems t,hrough their larger bandwidth, intrinsic safety, and built-in electrical isolation that reduces gate driver complexity. To develop t,he proposed optically-controlled power switches, this project will couple vertical GaN FinFET device structures with several methods, of optical carrier generation. Both direct bandgap as well as sub-bandgap optical generation will be studied and benchmarked for de,vice control, and their design and performance space will be identified. Inaddition to demonstrating new optically-controlled device,s, we will explore optical approaches to characterize the switches under operation. The optical waveguide used to illuminate the cha,nnel can also be used to measure light emitted during operation. This will create a real-time probe through which the electro-lumine,scence of GaN can be correlated with various metrics for performance and reliability. Moreover, the increased characterization capab,ility will be used to compare low-defect density bulk GaN wafers grown using the ammonothermal method to wafers grown through conven,tional hydride vapor phase epitaxy.The successful development of optically-controlled power transistors could have significant futur,e impact on many Navys electric platforms, including electric ships, planes, submarines, and micro-grids, among others. Additionall,y, real-time optical feedback can allow for easier built-in redundancy and safer operation through constant device monitoring. Beyon,d future potentialmilitary applications, we expect the basic research developed during this project to help understand and foster ne,w fundamental discoveries in light-matter interactions of III-nitride materials, and the impact of high electric fields on carrier t,ransport, recombination, and impact ionization, which will constitute the foundation of the next generation of power electronics.---, Approved for Public Release ---
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 08, 2022
- Source ID
- N000142212468
Entities
People
- Tomás Palacios
Organizations
- Massachusetts Institute of Technology
- Office of Naval Research
- United States Navy