The electronic structure of "-Ga2O3 thin films has been investigated by ab initio calculations and photoemission spectroscopy with UV, soft, and hard X-rays to probe the surface and bulk properties. The latter measurements reveal a peculiar satellite structure in the Ga 2p core level spectrum, absent at the surface, and a core-level broadening that can be attributed to photoelectron recoil. The photoemission experiments indicate that the energy separation between the valence band and the Fermi level is about 4.4 eV, a valence band maximum at the point and an effective mass of the highest lying bands of – 4.2 free electron masses. The value of the bandgap compares well with that obtained by optical experiments and with that obtained by calculations performed using a hybrid density-functional, which also reproduce well the dispersion and density of states.

The electronic structure of ε-Ga2O3 / Mulazzi, M.; Reichmann, F.; Becker, A.; Klesse, W. M.; Alippi, P.; Fiorentini, V.; Parisini, A.; Bosi, M.; Fornari, R.. - In: APL MATERIALS. - ISSN 2166-532X. - 7:2(2019), p. 022522. [10.1063/1.5054395]

The electronic structure of ε-Ga2O3

Fiorentini, V.;Parisini, A.;Fornari, R.
2019-01-01

Abstract

The electronic structure of "-Ga2O3 thin films has been investigated by ab initio calculations and photoemission spectroscopy with UV, soft, and hard X-rays to probe the surface and bulk properties. The latter measurements reveal a peculiar satellite structure in the Ga 2p core level spectrum, absent at the surface, and a core-level broadening that can be attributed to photoelectron recoil. The photoemission experiments indicate that the energy separation between the valence band and the Fermi level is about 4.4 eV, a valence band maximum at the point and an effective mass of the highest lying bands of – 4.2 free electron masses. The value of the bandgap compares well with that obtained by optical experiments and with that obtained by calculations performed using a hybrid density-functional, which also reproduce well the dispersion and density of states.
2019
The electronic structure of ε-Ga2O3 / Mulazzi, M.; Reichmann, F.; Becker, A.; Klesse, W. M.; Alippi, P.; Fiorentini, V.; Parisini, A.; Bosi, M.; Fornari, R.. - In: APL MATERIALS. - ISSN 2166-532X. - 7:2(2019), p. 022522. [10.1063/1.5054395]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11381/2854862
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