CEA, LETI, MINATEC Campus, Grenoble, France, Univ. Grenoble Alpes, Grenoble, France, Aix Marseille Université, CNRS, Université de Toulon, IM2NP UMR 7334, La Garde, France, Univ. Grenoble Alpes, CNRS, LTM, Grenoble, France, CNRS, LAAS, 7 avenue du colonel Roche, Toulouse, France, Univ de Toulouse, UPS, LAAS, Toulouse, France

To overcome the Fermi-level pinning in III-V metal-oxide-semiconductor capacitors, attention is usually focused on the choice of dielectric and surface chemical treatments prior to oxide deposition. In this work, we examined the influence of the III-V material surface cleaning and the semiconductor growth technique on the electrical properties of metal/Al2O3/In0.53Ga0.47As capacitors grown on InP(100) substrates. By means of the capacitance-voltage measurements, we demonstrated that samples do not have the same total oxide charge density depending on the cleaning solution used [(NH4)2S or NH4OH] prior to oxide deposition. The determination of the interface trap density revealed that a Fermi-level pinning occurs for samples grown by metalorganic chemical vapor deposition but not for similar samples grown by molecular beam epitaxy. Deep level transient spectroscopy analysis explained the Fermi-level pinning by an additional signal for samples grown by metalorganic chemical vapor deposition, attributed to the tunneling effect of carriers trapped in oxide toward interface states. This work emphasizes that the choice of appropriate oxide and cleaning treatment is not enough to prevent a Fermi-level pinning in III-V metal-oxide-semiconductor capacitors. The semiconductor growth technique needs to be taken into account because it impacts the trapping properties of the oxide. © 2017 Author(s).

Capacitance, Capacitors, Charge coupled devices, Chemical analysis, Chemical beam epitaxy, Cleaning, Deep level transient spectroscopy, Deposition, Dielectric devices, Dielectric materials, Fermi level, Interface states, Metal cleaning, Metallic compounds, Metallorganic chemical vapor deposition, Metals, Molecular beam epitaxy, MOS capacitors, MOS devices, Oxide semiconductors, Semiconducting indium phosphide, Semiconductor growth, Substrates, Surface cleaning, Transistors, Vapor deposition, Capacitance voltage measurements, Cleaning solution, Cleaning treatment, Fermi level pinning, Interface trap density, Metal-oxide-semiconductor capacitors, Oxide charge density, Trapping properties, III-V semiconductors