Modulation of the domain mode in GaN‐based planar Gunn diode for terahertz applications

Abstract This paper reports the modulation of the domain mode in the 2DEG channel of GaN HEMT‐like Gunn diodes by adjustment the electron concentration of the 2DEG near the cathode side. The enhancement of the electron concentration near the cathode side promotes the fast formation of the dipole domain layer and greatly reduces the dead zone length, which increases the RF output power. The employment of the recess layer near the cathode reduces the electron concentration of the 2DEG beneath it, which acts as a notch‐doped layer as in the bulk vertical diode. The reduction of the electron concentration of the 2DEG near the cathode promotes the formation of dual‐domain in one oscillation circle, which aims to enhance harmonic components of Gunn oscillation so as to minimize the use of frequency multipliers for SMMW and THz operation. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)