Investigations of Asymmetric Spacer Tunnel Layer (ASPAT) Diodes for High-Frequency Applications

摘要

A complete description of physical models for fabricated Asymmetric Spacer Tunnel Layer (ASPAT) diodes is reported in this work. A novel In0.53Ga0.47As/AlAs design is presented and compared to the conventional GaAs/AlAs material system. For both material schemes, physical models were developed based on experimental measurements. Simulated DC characteristics of the devices are given for both planar and back contacted structures to highlight the impact of spreading resistance on device behaviour. Furthermore, full s-parameter derivations from numerical simulation for tunnel diodes are demonstrated for the first time on the basis of quantum-mechanical AC modelling of the capacitance-voltage and conductance-voltage performances of these ASPAT diodes. A negligibly small difference between measured and simulated zero-biased intrinsic capacitances is observed (i.e. ≤ 0.2 fF). These are beneficial for accurate predictive models for device characteristics. In addition, key parameters which can be extracted from simulation results are obtained to aid in the development of mm-wave/THz