GaN MODFET microwave power technology for future generation radar and communications systems

In order to gain a better understanding of the role that GaN MODFET technology will play in future generation radar and communications systems, a comparison of the state-of-the-art performance of alternative microwave power technologies will be reviewed. The relative advantages and limitations of each technology will be discussed in relation to system needs. Device results from recent MBE-grown GaN MODFETs will also be presented. In particular, 0.25 mu m gate GaN MODFETs grown by MBE have been shown to exhibit less than 5% variation in maximum drain current density (I(dmax)) from the center to the edge of a 2 inch wafer. This level of uniformity is a substantially higher than that normally found in MOCVD-grown GaN devices (similar to 28% variation). In addition, evidence is also presented to demonstrate the excellent reproducibility of MBE-grown GaN MODFETs. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.