The valence-band offset has been determined to be 3.83± 0.05 eV at the atomic-layer-deposition Al 2 O 3 / InGaAs interface by x-ray photoelectron spectroscopy. The Au-Al 2 O 3 / InGaAs metal-oxide-semiconductor diode exhibits current-voltage characteristics dominated by Fowler-Nordheim tunneling. From the current-voltage data at forward and reverse biases, a conduction-band offset of 1.6± 0.1 eV at the Al 2 O 3-InGaAs interface and an electron effective mass ϳ0.28± 0.04m 0 of the Al 2 O 3 layer have been extracted. Consequently, combining the valence-band offset, the conduction-band offset, and the energy-band gap of the InGaAs, the energy-band gap of the atomic-layer-deposited Al 2 O 3 is 6.65± 0.11 eV.

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Atomic-layer-deposited high dielectric HfO 2 films on air-exposed In 0.53 Ga 0.47 As/ InP ͑100͒, using Hf͑NCH 3 C 2 H 5 ͒ 4 and H 2 O as the precursors, were found to have an atomically sharp interface free of arsenic oxides, an important aspect for Fermi level unpinning. A careful and thorough probing, using high-resolution angular-resolved x-ray photoelectron spectroscopy ͑XPS͒ with synchrotron radiation, however, observed the existence of Ga 2 O 3 , In 2 O 3 , and In͑OH͒ 3 at the interface. The current transport of the metal-oxide-semiconductor capacitor for an oxide 7.8 nm thick follows the Fowler-Nordheim tunneling mechanism and shows a low leakage current density of ϳ10 −8 A / cm 2 at V FB + 1 V. Well behaved frequency-varying capacitance-voltage curves were measured and an interfacial density of states of 2 ϫ 10 12 cm −2 eV −1 was derived. A conduction-band offset of 1.8Ϯ 0.1 eV and a valence-band offset of 2.9Ϯ 0.1 eV have been determined using the current transport data and XPS, respectively.

This paper describes a new technique called EncCon for visualizing and navigating large hierarchical information. This technique consists of two components: visualization and navigation. Visualization uses a fast enclosure + connection method to calculate the geometrical layout for the display of large hierarchies in a two-dimensional space. Our technique uses a rectangular division algorithm for recursively positioning the graph. This visualization aims to maximize the utilization of display space while retaining a good geometrical layout as well as a clear (explicit) presentation of the hierarchical structure of graphs. This paper also presents an experimental evaluation of EncCon's layout algorithm. Besides the layout algorithm, EncCon uses a new focus + context viewing technique for the navigation of large hierarchies. We use the zooming + layering concept to achieve the focus + context viewing, rather than the traditional enlarge + embedded concept, which is used by most of the available focus + context techniques. Technically, it employs semi-transparency to achieve the display of two layers of information in z-coordination at the same visualization. Both context view and detail view are drawn at two separate layers. These layers are then displayed in an overlapped manner at the same physical screen space.