Electrical properties of metal/Al 2 O 3 /In 0.53 Ga 0.47 As capacitors grown on InP

Philippe Ferrandis (1, 2) , Mathilde Billaud (3) , Julien Duvernay (1) , Mickaël Martin (3) , Alexandre Arnoult (4) , Helen Grampeix (1) , Mikael Casse (1) , Hervé Boutry (1) , Thierry Baron (3) , Maud Vinet (1) , Gilles Reimbold (1)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 IM2NP - Institut des Matériaux, de Microélectronique et des Nanosciences de Provence
3 LTM - Laboratoire des technologies de la microélectronique
4 LAAS-TEAM - Service Techniques et Équipements Appliqués à la Microélectronique

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 deposi-tion. 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/Al 2 O 3 /In 0.53 Ga 0.47 As 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 [(NH 4) 2 S or NH 4 OH] 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. Published by AIP Publishing.

Domaines: Science des matériaux [cond-mat.mtrl-sci]; Micro et nanotechnologies/Microélectronique

Philippe Ferrandis, Mathilde Billaud, Julien Duvernay, Mickaël Martin, Alexandre Arnoult, et al.. Electrical properties of metal/Al 2 O 3 /In 0.53 Ga 0.47 As capacitors grown on InP. Journal of Applied Physics, 2018, 123 (16), pp.161534. ⟨10.1063/1.5007920⟩. ⟨hal-01987681⟩