Department of Electrical Engineering and Information Technology, Institute for Microwave Engineering and Photonics (IMP), Technical University of Darmstadt, Darmstadt, Germany
Oktay Yilmazoglu
Department of Electrical Engineering and Information Technology, Institute for Microwave Engineering and Photonics (IMP), Technical University of Darmstadt, Darmstadt, Germany
Armin Dadgar
Faculty of Natural Sciences, Institute of Physics, Otto von Guericke University Magdeburg, Magdeburg, Germany
Franko Kuppers
Department of Electrical Engineering and Information Technology, Institute for Microwave Engineering and Photonics (IMP), Technical University of Darmstadt, Darmstadt, Germany
Thomas Kusserow
Department of Electrical Engineering and Information Technology, Institute for Microwave Engineering and Photonics (IMP), Technical University of Darmstadt, Darmstadt, Germany
For the first time, Gallium Nitride(GaN)-based Gunn diodes with side-contact and fieldplate technologies were fabricated and measured with reliable characteristics. A high negative differential resistance (NDR) region was characterised for the GaN Gunn effect using side-contact technology. The I-V measurement of the THz diode showed the ohmic and the Gunn effect region with high forward current of 0.65 A and high current drop of approximately 100 mA for a small ring diode width wd of 1.5 μm with 600 nm effective diode height hd at a small threshold voltage of 8.5 V. This THz diode worked stable due to good passivation as protection from electro-migration and ionisation between the electrodes as well as a better heat sink to the GaN substrate and large side-contacts. The diodes can provide for this thickness a fundamental frequency in the range of 0.3 - 0.4 THz with reliable characteristics.
