Full quantum simulation of Shockley-Read-Hall recombination in p-i-n and tunnel diodes

We have included Shockley-Read-Hall (SRH) generation/recombination in Non-equilibrium Green's function (NEGF) calculations via a multiphonon relaxation model. The model has been used to study how the presence of defects affects the current-voltage characteristics of GaAs p-i-n diodes, and of an InGaAs tunnel diode. Regarding p-i-n diodes, we show that SRH generation/recombination is responsible for ideality factors approaching the theoretical value of two in the forward bias regime, while in reverse bias the recombination current density varies slowly with the applied voltage. In all the considered cases, the defects located in the center of the active region proved to be the most effective in allowing trap-assisted tunneling from the valence to the conduction band. Finally, the inclusion of SRH recombination in NEGF simulations of Esaki tunnel diodes permits to predict a realistic degradation of the peak-to-valley current ratio.

Automated summary

In this study, the Shockley-Read-Hall (SRH) generation/recombination was incorporated into Non-equilibrium Green's function (NEGF) calculations using a multiphonon relaxation model. The effects of defects on the current-voltage characteristics of GaAs p-i-n diodes and InGaAs tunnel diodes were investigated. The results demonstrate that SRH generation/recombination is responsible for approaching the theoretical ideality factors in the forward bias regime and the recombination current density shows slow variation with applied voltage in the reverse bias regime. Defects located in the center of the active region were found to be the most effective in allowing trap-assisted tunneling. Additionally, the inclusion of SRH recombination in NEGF simulations of Esaki tunnel diodes accurately predicts the realistic degradation of the peak-to-valley current ratio.