Figure 8 shows the noise figure and gain of a 3-stage 60 percent In MHEMT Ka-band LNA with less than 1.
5V have hampered the output power density of some MHEMT devices and most InP HEMTs, predominately due to low on-state breakdown governed by the small band gap of their high indium content channels.
16 mm 3-stage 44 GHz power amplifier was fabricated using a 33 percent In MHEMT and demonstrated 1.
The authors would like to acknowledge the support of Chris McCarroll, Dave Laighton and David Van Buren, who are critical to the success of Raytheon's MHEMT program.
Later in 1997 Phil joined the research group at Raytheon RF Components in Andover, MA, where he is developing MHEMT device and fabrication technology for low noise amplifier applications.
He is engineering lead for Raytheon's development of wideband high dynamic range MHEMT LNAs for ONR.
In October 2000, he joined Advanced Device Research Lab, Raytheon, where he is currently working on MHEMT and GaN.
The strain-induced imperfections caused by high indium content channels on GaAs are eliminated in MHEMTs by providing a properly grown buffer between the substrate and active device layers.
1-x]As channel MHEMTs (x = 53 to 60 percent) have shown impressive results, achieving noise performance comparable to InP HEMTs with excellent linearity.
While GaAs PHEMTs and InP HEMTs are limited to In compositions near their lattice spacing, MHEMTs have a wide range of lattice constants that are available, and therefore enable the customization of the device's properties specific to each application.
His current interests are developing advanced MHEMTs, phosphorus-based MBE growth and nitride materials.