We propose to take the next steps in demonstrating a highly linear GaN/AlGaN MOSFET-based power amplifier that will be have increased power, improved linearity, high bandwidth, and improved adjacent channel power ratio over that presently achieved in other GaAs and GaN power amplifiers through Ka band. In this work, OSEMI will use it improved Gate-Oxide technology to form the gate passivating and insulating layer upon high performance GaN/AlGaN HEMT structures by MBE. We will use this new MBE technology to (1) optimize the nucleation of oxide on GaN/AlGaN Power MOSFET Structures, (2) grow bulk oxide films with a bandgap in excess of 4.5eV, (3) and produce oxide films that possess good interface properties and a low residual conductivity (4) and Fabricate Power FETs in collaboration with the University of Michigan. Devices will characterized at DC and RF frequencies, and load pull measurements using the University of Michigan's unique load-pull capability will be utilized in Phase I. Devices will be modeled using G-PICES-IIB and in Phase II it is anticipated that the prototype GaN/AlGaN MOSFET power amplifier will be fabricated and tested at OSEMI utilizing newly acquired processing equipment.