Abstract
The effects of hydrogen plasma treatment of β-Ga2O3 grown by halide vapor phase epitaxy and doped with Si are reported. Samples subjected to H plasma exposure at 330 °C developed a wide (∼2.5 μm-thick) region near the surface, depleted of electrons at room temperature. The thickness of the layer is in reasonable agreement with the estimated hydrogen penetration depth in β-Ga2O3 based on previous deuterium profiling experiments. Admittance spectroscopy and photoinduced current transient spectroscopy measurements place the Fermi level pinning position in the H treated film near Ec-1.05 eV. Annealing at 450 °C decreased the thickness of the depletion layer to 1.3 μm at room temperature and moved the Fermi level pinning position to Ec-0.8 eV. Further annealing at 550 °C almost restored the starting shallow donor concentration and the spectra of deep traps dominated by Ec-0.8 eV and Ec-1.05 eV observed before hydrogen treatment. It is suggested that hydrogen plasma exposure produces surface damage in the near-surface region and passivates or compensates shallow donors.
Original language | English |
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Article number | 032101 |
Journal | Applied Physics Letters |
Volume | 115 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2019 Jul 15 |
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)