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 technol ogy will play in future generation radar and communications systems, a comp arison of the state-of-the-art performance of alternative microwave power t echnologies will be reviewed. The relative advantages and limitations of ea ch 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 hig her than that normally found in MOCVD-grown GaN devices (similar to 28% var iation). In addition, evidence is also presented to demonstrate the excelle nt reproducibility of MBE-grown GaN MODFETs. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.