Compensation and hydrogen passivation of magnesium acceptors in β-Ga2O3

Magnesium-doped gallium oxide may be utilized as a semi-insulating material for future generations of power devices. Spectroscopy and hybrid functional calculations were used to investigate defect levels in Czochralski-grown β-Ga2O3. Substitutional Mg dopants act as deep acceptors, while substitutional Ir impurities are deep donors. Hydrogen-annealed Ga2O3:Mg shows an IR peak at 3492 cm−1, assigned to an O-H bond-stretching mode of a neutral MgH complex. Despite compensation by Ir and Si and hydrogen passivation, high concentrations of Mg (1019 cm−3) can push the Fermi level to mid-gap or lower.Magnesium-doped gallium oxide may be utilized as a semi-insulating material for future generations of power devices. Spectroscopy and hybrid functional calculations were used to investigate defect levels in Czochralski-grown β-Ga2O3. Substitutional Mg dopants act as deep acceptors, while substitutional Ir impurities are deep donors. Hydrogen-annealed Ga2O3:Mg shows an IR peak at 3492 cm−1, assigned to an O-H bond-stretching mode of a neutral MgH complex. Despite compensation by Ir and Si and hydrogen passivation, high concentrations of Mg (1019 cm−3) can push the Fermi level to mid-gap or lower.

[1]  Noboru Ichinose,et al.  Large-size β-Ga2O3 single crystals and wafers , 2004 .

[2]  Kelvin G. Lynn,et al.  Infrared spectroscopy of hydrogen in ZnO , 2002 .

[3]  S. Geller,et al.  Crystal Structure of β‐Ga2O3 , 1960 .

[4]  G. Kresse,et al.  Efficiency of ab-initio total energy calculations for metals and semiconductors using a plane-wave basis set , 1996 .

[5]  W. Tolksdorf,et al.  Optical Absorption, Fluorescence, and Electron Spin Resonance of Ir4+ on Octahedral Sites in Y3Ga5O12 , 1976 .

[6]  G. Scuseria,et al.  Hybrid functionals based on a screened Coulomb potential , 2003 .

[7]  G. Denninger,et al.  The oxygen vacancy in Ga2O3: a double resonance investigation , 2005, Magnetic resonance in chemistry : MRC.

[8]  S. Yamakoshi,et al.  Anisotropy, phonon modes, and free charge carrier parameters in monoclinic β-gallium oxide single crystals , 2015, 1512.08590.

[9]  Akito Kuramata,et al.  Device-Quality β-Ga2O3 Epitaxial Films Fabricated by Ozone Molecular Beam Epitaxy , 2012 .

[10]  Hideo Hosono,et al.  Anisotropy of electrical and optical properties in β-Ga2O3 single crystals , 1997 .

[11]  H. Hesse,et al.  Paramagnetic resonance and near-infrared optical absorption of SrTiO3:Ir4+ , 1984 .

[12]  A. Janotti,et al.  Hydrogenated cation vacancies in semiconducting oxides , 2011, Journal of physics. Condensed matter : an Institute of Physics journal.

[13]  Tohru Honda,et al.  Correlation between blue luminescence intensity and resistivity in β-Ga2O3 single crystals , 2013 .

[14]  Reinhard Uecker,et al.  On the bulk β-Ga2O3 single crystals grown by the Czochralski method , 2014 .

[15]  Reinhard Uecker,et al.  Electrical properties of β-Ga2O3 single crystals grown by the Czochralski method , 2011 .

[16]  J. L. Lyons.  A survey of acceptor dopants for β-Ga2O3 , 2018 .

[17]  Steffen Ganschow,et al.  Scaling-Up of Bulk β-Ga2O3 Single Crystals by the Czochralski Method , 2017 .

[18]  Blöchl,et al.  Projector augmented-wave method. , 1994, Physical review. B, Condensed matter.

[19]  J. Brice.  The growth of insulating crystals , 1977 .

[20]  N. Giles,et al.  Electron paramagnetic resonance study of neutral Mg acceptors in β-Ga2O3 crystals , 2017 .

[21]  Gustavo E. Scuseria,et al.  Erratum: “Hybrid functionals based on a screened Coulomb potential” [J. Chem. Phys. 118, 8207 (2003)] , 2006 .

[22]  Akito Kuramata,et al.  High-quality β-Ga2O3 single crystals grown by edge-defined film-fed growth , 2016 .

[23]  Ying Qin,et al.  Structure and vibrational properties of the dominant O-H center in β-Ga2O3 , 2018, Applied Physics Letters.

[24]  B. Svensson,et al.  Iron and intrinsic deep level states in Ga2O3 , 2018 .

[25]  L. Ledebo,et al.  Electrical properties of Fe in GaAs , 1983 .

[26]  Kresse,et al.  Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set. , 1996, Physical review. B, Condensed matter.

[27]  A. Yoshikawa,et al.  Floating zone growth of β-Ga2O3: a new window material for optoelectronic device applications , 2001 .

[28]  Jörg Neugebauer,et al.  Electrostatic interactions between charged defects in supercells , 2011 .

[29]  Akito Kuramata,et al.  Development of gallium oxide power devices , 2014 .

[30]  A. Janotti,et al.  Hydrogen donors in SnO 2 studied by infrared spectroscopy and first-principles calculations , 2010 .