Schottky diodes for terahertz applications

Abstract

The Schottky diode has been gaining more and more research interests as a THz source or detector. The aim of the work presented in this thesis is to optimise the Schottky anode contact in order to improve the ideality factor and noise properties. An investigation of the device properties has been carried out using different material structure (mainly based on GaAs) and surface preparation methods. A study of size or edge effects on the device properties was also included. Characterisation techniques used are electrical measurement (I-V and C- V) and surface analysis (AFM). Both I-V and C-V modelling and parameter extractions are implemented using Matlab. The best ideality factor obtained in this work is 1.12 for the largest diode (100x100 μm2) and 1.14 for the smallest diode (40x40 μm2).