Modulation of Multidomain in AlGaN/GaN HEMT-Like Planar Gunn Diode

Terahertz oscillations of AlGaN/GaN HEMT-like planar Gunn diodes with the channel length ranging from 0.6 to 1.6 $\mu{\rm m}$ have been investigated for the first time by means of numerical simulations at the Silvaco\´s ATLAS platform, with an emphasis on the mechanism of multiple domains coexisting in the 2-D electron gas (2-DEG) channel of planar Gunn diode. We found that the phenomenon of multidomain evidently influences the oscillation mode and the radio frequency performance of devices, and it is effective in redistributing the electric field throughout the 2-DEG channel by adjusting the doping concentration near the cathode side, which aims to modulate the formation of multidomain so as to enhance the output performance of planar Gunn diodes at terahertz frequencies.