In this paper we report some recent progress in 77GHz InP Gunn device process development. Specifically, utilizing an advanced dry etching tool to define InP Gunn diode mesas. Unlike FeCl3-based photochemical etches, the Inductively Coupled Plasma (ICP) offers excellent sidewall anisotropy and uniformity, which provides improved process consistency to facilitate mass manufacturablity of millime...

A current controlled bistable switching element using a CW Gunn diode is reported. With modest circuits switching rates of the order of 10 MHz have been obtained. Switching is initiated by current pulses of short duration (5 10 ns). Rise times of the order of several nanoseconds could be obtained. The apparent mechanism which allows the bistable operation of the Gunn diode is the reduction in t...

The GaN material parameters relevant to the negative di€erential resistance (NDR) devices are discussed, and their physical models based on the theoretical predictions and experimental device characteristics are introduced. Gunn diode design criteria were applied to design the GaN NDR diodes. A higher electrical strength of the GaN allowed operation with higher doping ( 10 cmÿ3) and at a higher...

Planar Indium Gallium Arsenide (In0.57Ga0.47As) Gunn diode was fabricated on a semi-insulating indium phosphide substrate with on chip matching circuit to enable the extraction of second harmonic in millimeter and terahertz frequencies. The In0.57Ga0.47As planar Gunn diodes were designed with an active length of 4 lm, channel width of 120 lm and integrated with a novel diamond resonator to supp...

GaN-based Negative Differential Resistance (NDR) diode oscillators have been studied by employing Gunn design criteria applicable to this material system. Numerical simulations were used to carry out large-signal analysis of the GaN NDR diode oscillators in order to evaluate their potential for THz signal generation. It was found that, due to the higher electron velocity and reduced time consta...

The conventional technique of realising waveguide resonators for Gunn diode oscillators to operate at the band edge of the waveguide fails owing to the excitation of a coaxial mode resonance formed by the post and the side walls of the waveguide. One of the solutions to the problem is to mount the diode in a ridged waveguide resonator, This has been demonstrated by constructing an 8 GHz Gunn os...

The dynamic characteristics of GaN-based Gunn and IMPATTs are reported at same operating conditions to find out the potentiality of each device to use as high frequency signal generator. The general model is developed by the author’s group considering all the physical phenomena for both the devices. It is seen that Double Drift Region IMPATTs produce better microwave power compare to Gunn diode...

The study of the radiation hardness subterahertz source from a Gunn diode oscillator and multiplier, based on semiconductor superlattice GaAs/AlAs was continued. dependences output power frequency before after neutron irradiation are experimentally measured. dependence to with fluences 3.5·10 12 , 2.85·10 13 10 14 cm -2 has been analytically estimated. Keywords: Radiation hardness, superlattice...

We propose a tunable microwave device consisting of a Gunn diode with time–delay feedback, which will emit chaotic microwaves. The wavelength is controlled by two incident laser beams which trigger moving multiple Gunn domains. Predicted phenomena include the coexistence of stationary and chaotic states, complicated hysteresis loops, and persistent bistabiliy. This device is potentially useful ...