Enhancement of effective dielectric constant using high-temperature mixed and sub-nano-laminated atomic layer deposited Y 2 O 3 /Al 2 O 3 on GaAs(001)
Journal
Microelectronic Engineering
Journal Volume
178
Pages
271-274
Date Issued
2017
Author(s)
Lin, K.Y.
Young, L.B.
Cheng, C.K.
Chen, K.H.
Lin, Y.H.
Wan, H.W.
Cai, R.F.
Lo, S.C.
Li, M.Y.
Kwo, J.
Abstract
In-situ atomic layer deposition (ALD) Y2O3/Al2O3 in bi-layered and sub-nano-laminated structures were stacked on pristine GaAs(001) substrates for fabricating metal-oxide-semiconductor capacitors. The bi-layered Y2O3/Al2O3 showed an enhanced effective dielectric constant from 11.1 to 15.6 in capacitance-voltage characteristics with post deposition annealing to 900 °C. No new oxide phase formed as carefully examined using synchrotron radiation X-ray diffraction and cross-sectional high-resolution scanning tunneling electron microscopy. We designed and grew sub-nano-laminated Y2O3/Al2O3 multi-layers to simulate the mixing of gate oxides, and observed an enhanced dielectric constant of 14.8 for the as-deposited sample. Both high-temperature mixed and sub-nano-laminated ALD Y2O3/Al2O3 exhibit high dielectric constant, low leakage current ~ 10− 8 A/cm2 and low interfacial trap density with GaAs(001), promising for high κ applications in future GaAs metal-oxide-semiconductor devices.
SDGs
Type
journal article