Characterization of high-{kappa} LaLuO{sub 3} thin film grown on AlGaN/GaN heterostructure by molecular beam deposition

Journal Article · Mon Oct 31 00:00:00 EDT 2011 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3657521· OSTI ID:22027795

Shu, Yang; Sen, Huang; Hongwei, Chen; Chen, Kevin J ^[1]; Schnee, Michael; Qingtai, Zhao; Schubert, Juergen ^[2]

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1. Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)
2. Peter Gruenberg Institute (PGI 9), Forschungszentrum Juelich, 52425 Juelich (Germany)

We report the study of high-dielectric-constant (high-{kappa}) dielectric LaLuO{sub 3} (LLO) thin film that is grown on AlGaN/GaN heterostructure by molecular beam deposition (MBD). The physical properties of LLO on AlGaN/GaN heterostrucure have been investigated with atomic force microscopy, x-ray photoelectron spectroscopy, and TEM. It is revealed that the MBD-grown 16 nm-thick LLO film is polycrystalline with a thin ({approx}2 nm) amorphous transition layer at the LLO/GaN interface. The bandgap of LLO is derived as 5.3 {+-} 0.04 eV from O1s energy loss spectrum. Capacitance-voltage (C-V) characteristics of a Ni-Au/LLO/III-nitride metal-insulator-semiconductor diode exhibit small frequency dispersion (<2%) and reveal a high effective dielectric constant of {approx}28 for the LLO film. The LLO layer is shown to be effective in suppressing the reverse and forward leakage current in the MIS diode. In particular, the MIS diode forward current is reduced by 7 orders of magnitude at a forward bias of 1 V compared to a conventional Ni-Au/III-nitride Schottky diode.

• OSTI ID: 22027795
• Journal Information: Applied Physics Letters, Vol. 99, Issue 18; Other Information: (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM COMPOUNDS
ATOMIC FORCE MICROSCOPY
CAPACITANCE
DIELECTRIC MATERIALS
ENERGY GAP
ENERGY-LOSS SPECTROSCOPY
GALLIUM NITRIDES
HETEROJUNCTIONS
INTERFACES
LANTHANUM COMPOUNDS
LEAKAGE CURRENT
MOLECULAR BEAM EPITAXY
MOLECULAR BEAMS
PERMITTIVITY
POLYCRYSTALS
SCHOTTKY BARRIER DIODES
SEMICONDUCTOR MATERIALS
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY PHOTOELECTRON SPECTROSCOPY