Harnessing the potential of single crystal inorganic nanowires for practical advanced nanoscale applications requires not only reproducible synthesis highly regular one-dimensional (1D) nanowire arrays directly on device platforms but also elegant integration which retains structural integrity while significantly reducing or eliminating complex critical processing steps. Here we demonstrate a unique, direct, and bottom-up semiconductor 1D nanowire, using zinc oxide (ZnO) as an example, to...

We demonstrate seamless direct integration of a semiconductor nanowire grown using bottom-up approach to obtain vertical field-effect transistor (VFET). first synthesize single crystalline indium oxide (In2O3) nanowires projecting vertically and uniformly on nonconducting optical sapphire substrate. Direct electrical contact the is uniquely provided by self-assembled underlying In2O3 buffer layer formed in-situ during growth. A controlled time-resolved growth study reveals dynamic...

In this paper, high-speed surface-illuminated Ge-on-Si pin photodiodes with improved efficiency are demonstrated. With photon-trapping microhole features, the external quantum (EQE) of diode is >80% at 1300 nm and 73% 1550 nm an intrinsic Ge layer only 2 μm thickness, showing much improvement compared to one without microholes. More than threefold EQE also observed longer wavelengths beyond 1550 nm. These results make microhole-enabled promising cover both existing C L bands, as well a new...

The in-plane transport properties of a strained (100) Si layer on relaxed Si1−xGex substrate are studied with an ensemble Monte Carlo technique. Similar velocity (-field) characteristics found for any valley splitting energy ΔE≥0.1 eV. These phonon-limited electron mobilities reach 4000 cm2/V s at 300 K, and 23 000 77 K. There is only slight increase in the saturation both temperatures. However, significant overshoot peak transient to depend upon ΔE, ΔE=0.4 eV, reaches 4.1×107 cm/s 5.2×107

It has been suggested by theoretical calculation that indium antimonide (InSb) nanowires can possess improved thermoelectric properties compared to the corresponding bulk crystal. Here we fabricated a device using electron beam lithography measure thermopower and electrical conductivity of an individual InSb nanowire grown vapor-liquid-solid method. The comparison between measurement results transport simulations reveals was unintentionally degenerately doped with donors. Better control...

We present temperature-dependent electrical characteristics of vertically aligned carbon nanofiber (CNF) arrays for on-chip interconnect applications. The study consists three parts. First, the electron transport mechanisms in these structures are investigated using I-V measurements over a broad temperature range (4.4 K to 350 K). measured resistivity CNF is modeled based on known graphite two-dimensional hopping conduction mechanism. model used because disordered structure observed during...

To realize nanocarbons in general and carbon nanotube (CNT) particular as on-chip interconnect materials, the contact resistance stemming from metal?CNT interface must be well understood minimized. Understanding complex mechanisms at can lead to effective reduction. In this study, we compile existing published results understanding for two geometries, sidewall or side end contact, address key performance characteristics which low resistance. Side contacts typically result resistances >1 k?,...

The photosensitivity of silicon is inherently very low in the visible electromagnetic spectrum, and it drops rapidly beyond 800 nm near-infrared wavelengths. We have experimentally demonstrated a technique utilizing photon-trapping surface structures to show prodigious improvement photoabsorption 1-μm-thin silicon, surpassing inherent absorption efficiency gallium arsenide for broad spectrum. allow bending normally incident light by almost 90 deg transform into laterally propagating modes...

This study presents an ultra-thin backside illuminated (BSI) and top-illuminated germanium (Ge) on silicon (Si) photodetector (PD) designed for a wavelength range of 1 to 1.4 microns. Monte Carlo molecular dynamics simulations, incorporating charge transport, were employed model the electron-hole current within device, which features integrated nano-micro hole structures aimed at optimizing high-speed performance. design enables wide-spectral response, high efficiency, ultra-fast operation...

Transport properties of ungated Si/Si/sub 1-x/Ge/sub x/ are studied by an ensemble Monte Carlo technique. The device performance is with a quantum hydrodynamic equation method using the results. phonon-scattering limited mobility enhanced over bulk Si, and found to reach 23000 cm/sup 2//Vs at 77 K 4000 300 K. saturation velocity increased slightly compared value both temperatures. A significant overshoot, several times larger than velocity, also found. In typical modulation-doped...

A model is proposed for the previously reported lower Schottky barrier ${\ensuremath{\Phi}}_{\mathrm{Bh}}$ hole transport in air than vacuum at a junction between metallic electrode and semiconducting carbon nanotube (CNT). We consider electrostatics transition region CNT presence or absence of oxygen molecules (air vacuum), where an appreciable potential drop occurs. The role to increase this with negative charge, leading air. modulation large when depletion mode involved, while negligible...

Current-induced breakdown is investigated for carbon nanofibers (CNF) potential interconnect applications. The measured maximum current density in the suspended CNF inversely proportional to nanofiber length and independent of diameter. This relationship can be described with a heat transport model that takes into account Joule heating diffusion along CNF, assuming occurs when where temperature reaches threshold or critical value.

A surface-illuminated silicon photodiode with both high speed and usable external quantum efficiency from 900 to 1000 nm wavelength is highly desirable for intra/inter data center Ethernet communications, performance computing, laser radar application. Such Si photodiodes have the potential monolithic integration CMOS integrated circuits which can significantly reduce cost of transmission per gigabit below one US dollar. To overcome silicon's intrinsic weakness absorption in these...

An equivalent circuit model is proposed for the Schottky barrier at junction between a metallic electrode and semiconducting carbon nanotube (NT). We have applied to gold-NT under presence of neutral polarized NH3 molecules, shown that visible modulation possible gas densities as low 3×1013cm−2, which quite feasible experimentally.

Improvements in thermal interface materials (TIMs) can enhance heat transfer electronics packages and reduce high temperatures. TIMs are generally composed of highly conductive particle fillers a matrix that allows for good surface wetting compliance the material during application. Two types tested based on addition carbon nanotubes (CNTs): one mixed with commercial TIM product other only CNTs silicone oil. The using an in-house apparatus simultaneous measurement temperature, pressure,...

Photodetectors (PDs) used in communication systems require ultrafast response, high efficiency, and low noise. PDs with such characteristics are increasingly demand for data centers, metro links, long-haul optical networks. In a surface-illuminated PD, speed efficiency often tradeoff, since high-speed device needs thin absorption layer to reduce the carrier transit time, whereas high-efficiency thick compensate coefficient of some semiconductors as Si Germanium (Ge) or SiGe alloys at...

We study the performance and reliability of carbon nanofiber (CNF) interconnects under high-current stress by examining CNF breakdown for four test configurations, suspended/supported with/without tungsten deposition. The use W is to improve CNF-electrode contact. supported cases show a larger current density just before than suspended ones, suggesting an effective heat dissipation substrate. W-deposited contacts reduce initial total resistance from megaohm range without kilo-ohms....

We present an in-depth electrical characterization of contact resistance in carbon nanostructure via interconnects. Test structures designed and fabricated for applications contain vertically aligned arrays nanofibers (CNFs) grown on a thin titanium film silicon substrate embedded dioxide. Current-voltage measurements are performed single CNFs using atomic force microscope current-sensing technique. By analyzing the dependence measured CNF diameter, we extract resistivity metal-CNF resistance.

To elucidate the observed current capacity behavior, a model is developed that takes into account heat transport through entire carbon nanofiber interconnect test structure and breakdown location. The also includes variations in contact location with support material. resulting predicted dissipation are completely consistent experimental data.

Due to relatively low responsivity at near infrared (NIR) wavelengths, surface-illuminated silicon (Si) photodiodes (PDs) are not attractive for ultra-fast data communication applications despite their CMOS-compatibility. Metal-semiconductor-metal (MSM) well-known simplicity in fabrication compared pin and pn junctions-based counterparts, but they usually work with lower efficiencies due thin absorption layer that ensures high speed response. In this letter, we demonstrate a efficiency...

Pb islands grown on a Si substrate transform at room temperature from flattop facet geometry into an unusual ring shape. The volume-preserving mass transport is catalyzed by the electrical field tip of scanning tunneling microscope. morphology results competing classical and quantum effects in shape relaxation. latter enhanced large anisotropy effective mass, leads to sequential strip-flow growth alternating strips same defined steps, showing its dynamical impact stability nanostructure.