Impact of Donor Ionization on 2DEG Charge Density in δ-Doped β-(AlxGa1-x)2O3/Ga2O3 HFET: An Analytical Study

An analytical model for 2-dimensional electron gas (2D
$E$
G) charge density
$(\mathrm{n}_{\mathrm{s}})$
in
$\beta-(\mathrm{A}1_{\mathrm{x}}\text{Ga}1-\mathrm{x})_{2}\mathrm{O}_{3}/\text{Ga}2\mathrm{O}_{3}$
Heterostructure Field Effect Transistor. The presented model takes into account the incomplete donor ionization. The model is solved region-wise owing to the complex
$\mathrm{n}_{\mathrm{s}}$
variation with Fermi level. The presented model agrees well with numerical solution and experimental data. The model is then used to study the effect of donor ionization energy and donor density on 2DEG charge density.