New Approaches to Realizing High Power Nitride Based Field Effect Transistors

Abstract

We report on several key innovations to enable high performance/high reliability of nitride based FETs that include (1) the use of Perforated Channel (PC) design; (2) surface application of Low Conducting Layers (LCLs); (3) the combination of these two approaches (for achieving the ultimate power performance at the highest switching frequencies with minimum losses); (4) novel device geometries (combining the best features of lateral and vertical devices for normally-off transistors); (5) improved control of self-heating and better heat dissipation. We also review our recent results exploring the PC channel and LCL designs . Our experimental and simulation results demonstrated a sharp increase in the breakdown voltage, a large enhancement of the cutoff frequency, a better device stability and smaller spreading of the device parameters for higher yield, improved manufacturability, and smaller self-heating due to a lower thermal impedance.