Reduction of Impact Ionization in GaAs-Based Planar Gunn Diodes by Anode Contact Design

Impact ionisation electroluminescence in planar GaAs-based heterostructure Gunn diodes: Spatial distribution and impact of doping non-uniformities

“…As the rate of impact ionisation in planar Gunn diodes depends only on the electric field and the electron charge density in the Gunn domains on the one hand, and the electron density underneath the anode edge and the other, holes are generated uniformly along the anode contact every time a Gunn domain reaches the anode edge 5 . This, however, does not reflect what is observed experimentally, i.e.…”

“…This indicates the presence of a significant impact ionisation in the devices taking place when the travelling Gunn domains impinge on the anode contact edge, resulting in the generation of holes next to this contact 5 . The observed EL is not uniformly distributed over the device channel, but rather forms non-uniform patterns parallel to the anode whose intensity also varies along the device channel, being higher right next to the anode contact edge (Figure 1(a)).…”

Comparative Monte Carlo analysis of InP- and GaN-based Gunn diodes

“…It is mostly due to the proximity of the metal contacts and to the high bias required for these devices to work in the NDR conditions which typically causes the diodes to burn out before oscillating. 13,14 Nowadays, as alternative to traditional vertical Gunn diodes, different structures are being explored, highlighting planar structures, such as InGaAs/InAlAs, 15 GaAs/AlGaAs, [16][17][18] and InGaAs/AlGaAs planar diodes, 19 and GaN/AlGaN self-switching-diodes (SSDs). 20 In this work, our aim is to present a theoretical comparative study of the amplitude and frequency of the oscillations provided by InP and GaN vertical diodes (with and without notch) by means of a home-made Monte Carlo (MC) simulator 21,22 used to calculate the current power spectral density (PSD) in the diodes.…”

Thermal Profiles Within the Channel of Planar Gunn Diodes Using Micro-Particle Sensors

“…As the DC input power was further increased, the temperature profile became more asymmetric, suggesting regions of increased current density (current filaments), which would further limit RF output power. Current filaments have been observed using electroluminescence (EL) [10] with similar geometry devices, and with Schottky contact over-layers more consistent current flow across the width of the device was observed.…”