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arXiv · 2010.00193

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

Anil Kumar Rajapitamahuni·Laxman Raju Thoutam·Praneeth Ranga·Sriram Krishnamoorthy·Bharat Jalan
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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.

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Anil Kumar Rajapitamahuni, Laxman Raju Thoutam, Praneeth Ranga, Sriram Krishnamoorthy, Bharat Jalan. 2020-10-01. Impurity Band Conduction in Si-doped \b{eta}-Ga2O3 Films. https://doi.org/10.1063/5.0031481

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