Impurity Band Conduction in Si-doped \b{eta}-Ga2O3 Films

TL;DR

This study investigates impurity band conduction in Si-doped ta-Ga2O3 films using temperature-dependent resistivity and high magnetic field Hall effect measurements, revealing donor energy levels and defect states.

Contribution

It provides new insights into impurity band conduction and defect energy states in ta-Ga2O3 through high-field magnetotransport analysis.

Findings

Identified donor energies of approximately 33.7 and 45.6 meV.

Observed non-linear Hall resistance indicating two-band conduction at low temperatures.

Suggested the presence of residual donor states, likely DX centers.

Abstract

By combining temperature-dependent resistivity and Hall effect measurements, we investigate donor state energy in Si-doped \b{eta}-Ga2O3 films grown using metal-organic vapor phase epitaxy (MOVPE). High magnetic field Hall effect measurements (H = +/-90 kOe) showed non-linear Hall resistance for T < 150 K revealing two-band conduction. Further analyses revealed carrier freeze-out characteristics in both bands yielding donor state energies of ~ 33.7 and ~ 45.6 meV. The former is consistent with the donor energy of Si in \b{eta}-Ga2O3 whereas the latter suggests a residual donor state, likely associated with a DX center. This study provides a critical insight into the impurity band conduction and the defect energy states in \b{eta}-Ga2O3 using high-field magnetotransport measurements.