InAs Nanowires (InA + nanowire)

Distribution by Scientific Domains


Selected Abstracts


Modeling and performance analysis of high-speed, low-power InAs nanowire field-effect transistors

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 10 2010
M. Abul Khayer
Abstract The performance metrics of InAs nanowire (NW) field-effect transistors (FETs) are investigated using an analytical 2-band model and a semiclassical ballistic transport model. The analysis of the diameter dependence of the current, gate delay, power-delay product, and energy-delay product of InAs NW FETs are presented. Because of their small density of states, relatively large diameter, , 60 nm, InAs NW FETs operate in the quantum capacitance limit (QCL). Both the energy-delay and power-delay products are reduced as the diameter is reduced, and optimum designs are obtained for diameters in the range of 10 , 40 nm. Power-delay product varies from 2 × 10,20 J to 63 × 10,20 J for all devices with a source Fermi level range of 0.1 , 0.2 eV. The gate delay time for all devices varies from 4 , 16 fs and decreases as the NW diameter increases. These NW FETs provide both ultra-low power switching and high-speed (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Structural and Room-Temperature Transport Properties of Zinc Blende and Wurtzite InAs Nanowires

ADVANCED FUNCTIONAL MATERIALS, Issue 13 2009
Shadi A. Dayeh
Abstract Here, direct correlation between the microstructure of InAs nanowires (NWs) and their electronic transport behavior at room temperature is reported. Pure zinc blende (ZB) InAs NWs grown on SiO2/Si substrates are characterized by a rotational twin along their growth-direction axis while wurtzite (WZ) InAs NWs grown on InAs (111)B substrates have numerous stacking faults perpendicular to their growth-direction axis with small ZB segments. In transport measurements on back-gate field-effect transistors (FETs) fabricated from both types of NWs, significantly distinct subthreshold characteristics are observed (Ion/Ioff,,,2 for ZB NWs and ,104 for WZ NWs) despite only a slight difference in their transport coefficients. This difference is attributed to spontaneous polarization charges at the WZ/ZB interfaces, which suppress carrier accumulation at the NW surface, thus enabling full depletion of the WZ NW FET channel. 2D Silvaco-Atlas simulations are used for ZB and WZ channels to analyze subthreshold current flow, and it is found that a polarization charge density of ,1013,cm,2 leads to good agreement with experimentally observed subthreshold characteristics for a WZ InAs NW given surface-state densities in the 5,×,1011,5,×,1012,cm,2 range. [source]


Nanowire-Induced Wurtzite InAs Thin Film on Zinc-Blende InAs Substrate

ADVANCED MATERIALS, Issue 36 2009
Jiming Bao
InAs pyramids and platelets on a zinc-blende InAs substrate are found to exhibit a wurtzite crystal structure. Induced by wurtzite InAs nanowires, wurtzite InAs thin film and its associated zinc-blende/wurtzite heterocrystalline heterostructures may open up new opportunities in band-gap engineering and related device applications. [source]


Cover Picture: Dendritic Nanowire Growth Mediated by a Self-Assembled Catalyst (Adv. Mater.

ADVANCED MATERIALS, Issue 5 2005
5/2005)
Abstract The dendritic nanostructures shown on the cover background were generated by self-assembled Mn clusters deposited from the vapor phase during vapor,liquid,solid growth of InAs nanowires. By carefully controlling the timing and amount of the Mn precursor, on p.,598 Lauhon and co-workers demonstrate a route to the formation of ordered hierarchical nanowire structures shown from various perspectives in the cover insets. [source]


High-resolution three-dimensional reciprocal-space mapping of InAs nanowires

JOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 3 2009
S. O. Mariager
Grazing-incidence X-ray diffraction is combined with a two-dimensional pixel detector to obtain three-dimensional reciprocal-space maps of InAs nanowires grown by molecular beam epitaxy. This rapid data-acquisition technique and the necessary correction factors are described in general terms, as well as for the specific setup used, for which a resolution of ,2 × 10,3,Å is computed. The three-dimensional data sets are obtained by calculating the reciprocal space coordinates for every pixel in the detected images, and are used to map the diffuse scattering from the nanowires as both two-dimensional reciprocal-space maps and three-dimensional isosurfaces. The InAs nanowires are shown to consist mainly of wurtzite crystal with a c/a ratio of 1.641. The diffuse scattering reveals two different facet structures, both resulting in hexagonal cross sections of the nanowires. [source]