Surface Passivation Using Lanthanide Oxynitrides for GaAs Metal-Oxide-Semiconductor Applications

L. N. Liu, W. M. Tang, X. D. Huang, J. P. Xu, P. T. Lai

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

Different lanthanide oxynitrides (LaON, NdON, CeON, and GdON) are applied as the interfacial passivation layers (IPLs) for GaAs metal-oxide-semiconductor (MOS) capacitors with HfO2 as the gate dielectric. The measurement results show that all the IPLs can improve the quality of the HfO2/GaAs interface by suppressing the in-diffusions of Hf and O toward the GaAs surface from the gate dielectric, and thus the growth of unstable Ga/As oxides as proved by the atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS) analysis. Among the IPLs, the LaON IPL shows the best passivating effect on the GaAs surface, and so the relevant MOS capacitor exhibits the lowest interface-state density (8× 10-11} cm-2eV-1), smallest flat-band voltage (0.65 V), negligible hysteresis (33 mV), lowest gate leakage (1.08× 10-6 A/cm2 at Vtext fb + 1 V), smallest frequency dispersion (2.85% in accumulation region), and good high-field reliability. NdON exhibits slightly less performance improvement than LaON, but its lower cost and higher moisture resistance can enhance its potential for GaAs surface passivation.

Original languageEnglish
Article number8718026
Pages (from-to)3080-3085
Number of pages6
JournalIEEE Transactions on Electron Devices
Volume66
Issue number7
DOIs
Publication statusPublished - 1 Jul 2019

Keywords

  • GaAs MOS
  • high-k interfacial passivation layer (IPL)
  • interface states density
  • lanthanide oxynitride

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

Cite this