A Comparative Study of Fixing One BarrierVarying Another Barrier for a Resonant Tunneling Diode

Abstract

In this research paper, the effects of fixing one barrier
and varying another barrier have been analyzed and compared
for a GaAs/Al0.3Ga0.7As based double barrier resonant
tunneling diode for two different models - Hartree Quantum
Charge model and semi-classical Thomas Fermi model. VI
characteristic graphs are studied to assess the overall
performance of both models. The simulations are carried out in a
nanoelectronics modeling tool suite – Nano electronic Modelling 5
(NEMO5) considering Non-Equilibrium Green’s Function
(NEGF), at room temperature of 300K and biased voltage of 0 to
0.5 V. In this paper, it was demonstrated that a very larger
amount of current is supplied by both models when the first
barrier is varied and second barrier is fixed in comparison to the
first barrier when kept fixed and second barrier is varied. But as
quantum charge inside the quantum well is existed in the Hartree
model, so overall Hartree model supplied a greater amount of
current compared to the Thomas Fermi model. Quantum charge
inside its quantum well is not present in the Thomas Fermi
model. But a better NDR region is created by the Thomas Fermi
model in both varied first barrier-fixed second barrier and fixed
first barrier-varied second barrier cases compared to the Hartree
model. This NDR region can be used for numerous digital
applications. On the other hand, a vast range of analog
applications can be used by the Hartree model that produced
larger current per unit voltage.