Browsing by Author "Tung, L. T."

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Al(2)O(3)/Ga(2)O(3)(Gd(2)O(3)) passivation on In(0.20)Ga(0.80)As/GaAs-structural intactness with high-temperature annealing
(2010-04-07)
Lee, Y. J.
;
Lee, C. H.
;
Tung, L. T.
;
Chiang, T. H.
;
Lai, T. Y.
Molecular beam epitaxy grown Al(2)O(3)/Ga(2)O(3)(Gd(2)O(3))/In(0.20)Ga(0.80)As/GaAs has been rapidly thermal annealed to 850 degrees C in N(2). The hetero-structure remained intact, with the In(0.20)Ga(0.80)As/GaAs interface being free of misfit dislocation and In(0.20)Ga(0.80)As strained, as observed by high-resolution transmission electron microscopy and high-resolution x-ray diffraction using synchrotron radiation. Excellent capacitance-voltage characteristics as well as low electrical leakages were obtained. These structural and electrical results demonstrate that employing Ga(2)O(3)(Gd(2)O(3)) as a dielectric with an in situ Al(2)O(3) capping layer efficiently protects strained InGaAs layers from relaxing and volatilizing during rapid thermal annealing to 850 degrees C, important for fabricating inversion-channel InGaAs metal-oxide-semiconductor field-effect-transistors, a candidate for beyond the 16 nm node complementary MOS technology.
Al2O3/Ga2O3(Gd2O3) passivation on In0.20Ga0.80As/GaAs-structural intactness with high-temperature annealing
(2010-04-07)
Lee, Y. J.
;
Lee, C. H.
;
Tung, L. T.
;
Chiang, T. H.
;
Lai, T. Y.
Molecular beam epitaxy grown Al2O3/Ga2O3(Gd2O3)/In0.20Ga0.80As/GaAs has been rapidly thermal annealed to 850 degrees C in N-2. The hetero-structure remained intact, with the In0.20Ga0.80As/GaAs interface being free of misfit dislocation and In0.20Ga0.80As strained, as observed by high-resolution transmission electron microscopy and high-resolution x-ray diffraction using synchrotron radiation. Excellent capacitance-voltage characteristics as well as low electrical leakages were obtained. These structural and electrical results demonstrate that employing Ga2O3(Gd2O3) as a dielectric with an in situ Al2O3 capping layer efficiently protects strained InGaAs layers from relaxing and volatilizing during rapid thermal annealing to 850 degrees C, important for fabricating inversion-channel InGaAs metal-oxide-semiconductor field-effect-transistors, a candidate for beyond the 16 nm node complementary MOS technology.
Growth and structural characteristics of GaN/AlN/nanothick gamma-Al(2)O(3)/Si (111)
(2008-05-01)
Lee, W. C.
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Lee, Y. J.
;
Tung, L. T.
;
Wu, S. Y.
;
Lee, C. H.
The authors report on the growth of GaN by nitrogen plasma-assisted molecular beam epitaxy (MBE) on a 2 in. Si (111) substrates with a nanothick (similar to 4.8 nm thick) gamma-Al(2)O(3) as a template/buffer. A thin layer of MBE-AlN similar to 40 nm thick was inserted prior to the growth of GaN. High-resolution transmission electron microscopy (HR-TEM) and high-resolution x-ray diffraction studies indicated that both of the nanothick gamma-Al(2)O(3) and AlN are a single crystal. Reflection high-energy electron diffraction, high-resolution x-ray scattering using synchrotron radiation, and cross-sectional HR-TEM measurements indicated an orientation relationship of GaN(0002)parallel to AlN(0002)parallel to gamma-Al(2)O(3)(111)parallel to Si(111) and GaN[10-10]parallel to AlN[10-10]parallel to gamma-Al(2)O(3)[2-1-1]parallel to Si[2-1-1]. A dislocation density of 5x(10(8)-10(9))/cm(2) in the GaN similar to 0.5 mu m thick was determined using cross-sectional TEM images under weak-beam dark-field conditions. (C) 2008 American Vacuum Society.