We present the results of a thorough study wet chemical methods for transferring vapor deposition grown graphene from metal growth substrate to device-compatible substrate. On basis these results, we have developed "modified RCA clean" transfer method that has much better control both contamination and crack formation does not degrade quality transferred graphene. Using this method, high device yields, up 97%, with narrow performance metrics distribution were achieved. This demonstration...

A rewriteable low-power operation nonvolatile physically flexible memristor device is demonstrated. The active component of the inexpensively fabricated at room temperature by spinning a TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> sol gel on commercially available polymer sheet. exhibits memory behavior consistent with memristor, demonstrates an on/off ratio greater than 10 000 : 1, for over 1.2 times <sup...

The molecular orientation of regioregular poly(3-hexylthiophene) varies from edge-on to plane-on depending on the film drying rate controlled by spin-coating speed. field effect hole mobility accordingly. Orientation was determined with near-edge X-ray fine structure spectroscopy π* resonance, which is orthogonal conjugated plane.

We present measurements showing dramatic nonlocal behavior in the four-terminal resistances of a high-mobility quantum Hall conductor. These illustrate that standard definition resistivity tensor is inappropriate, but they are excellent agreement with new model conductor treats edge and bulk conducting pathways independently. This uses single intensive parameter, analogous to local for channel only, characterize system.

We determined the band alignment of a graphene-insulator-semiconductor structure using internal photoemission spectroscopy. From flatband voltage and Dirac voltage, we infer 4.6× 1011cm−2 negative extrinsic charge present on graphene surface. Also, extract work function to be 4.56 eV, in excellent agreement with theoretical experimental values literature. Electron hole injection from heavily doped p-type silicon (Si) are both observed. The barrier height top valence Si bottom conduction...

We report reduced contact resistance of single-layer graphene devices by using ultraviolet ozone (UVO) treatment to modify the metal/graphene interface. The were fabricated from mechanically transferred, chemical vapor deposition (CVD) grown, single layer graphene. UVO in regions as defined photolithography and prior metal was found reduce interface contamination originating incomplete removal poly(methyl methacrylate) (PMMA) photoresist. Our control experiment shows that exposure times up...

Developing processes to controllably dope transition-metal dichalcogenides (TMDs) is critical for optical and electrical applications. Here, molecular reductants oxidants are introduced onto monolayer TMDs, specifically MoS

Recently emerging large-area single-layer MoS2 grown by chemical vapor deposition has triggered great interest due to its exciting potential for applications in advanced electronic and optoelectronic devices. Unlike gapless graphene, an intrinsic band gap the visible which crosses over from indirect a direct when reduced single atomic layer. In this article, we report comprehensive study of fundamental optical properties revealed spectroscopy Raman, photoluminescence, vacuum ultraviolet...

In this work, we compare the electrical characteristics of MoS2 field-effect transistors (FETs) with Ag source/drain contacts those Ti and demonstrate that metal–MoS2 interface is crucial to device performance. FETs show more than 60 times higher ON-state current contacts. order better understand mechanism performance contacts, 5 nm Au/5 (contact layer) or film was deposited onto monolayers few layers, topography metal films characterized using scanning electron microscopy atomic force...

The optical properties of a set high-k dielectric HfO2 films annealed at various high temperatures were determined by spectroscopic ellipsometry. results show that the characteristics functions these are strongly affected temperature annealing. For sample 600 °C, film becomes polycrystalline, and its function displays distinctive peak 5.9 eV. On other hand, remains amorphous without eV feature after 500 °C To model functions, Tauc–Lorentz dispersion was successfully adopted for...

Silicon nanowire field-effect transistors (SiNWFETs) have been fabricated with a highly simplified integration scheme to function as Schottky barrier excellent enhancement-mode characteristics and high on/off current ratio ∼107. SiNWFETs show significant improvement in the thermal emission leakage (∼6 × 10−13 A µm−1) compared reference FETs larger channel width (∼7 10−10 µm−1). The drain level depends substantially on contact metal work determined by examining devices different source/drain...

Dual-gated silicon nanowire (SiNW) field-effect transistors (FETs) have been fabricated by using electron-beam lithography. SiNW devices (W ≈ 60 nm) exhibit an on/off current ratio greater than 106, which is more 3 orders of magnitude higher that control prepared simultaneously having a large channel width (∼5 μm). In addition, changing the local energy-band profile channel, top gate found to suppress ambipolar conduction effectively, one factors limiting use nanotube or FETs for...

Topological insulators are unique electronic materials with insulating interiors and robust metallic surfaces. Device applications exploiting their remarkable properties have so far been hampered by the difficulty to electrically tune Fermi levels of both bulk thin film samples. Here we show experimentally that single-crystal nanowires topological insulator Bi2Se3 can be used as conduction channel in high-performance field effect transistor (FET), a basic circuit building block. Its...

The organic charge‐transfer complex dibenzotetrathiafulvalene–7,7,8,8‐tetracyanoquinodimethane is found to crystallize in two polymorphs when grown by physical vapor transport: the known α‐polymorph and a new structure, β‐polymorph. Structural elemental analysis via selected area electron diffraction, X‐ray photoelectron spectroscopy, polarized IR spectroscopy reveal that complexes have same stoichiometry with 1:1 donor: acceptor ratio, but exhibit unique unit cells. structural variations...

Since the first observation of spin-valve effect through organic semiconductors, efforts to realize novel spintronic technologies based on semiconductors have been rapidly growing. However, a complete understanding spin-polarized carrier injection and transport in is still lacking under debate. For example, there no clear major spin-flip mechanisms role hybrid metal-organic interfaces spin injection. Recent findings suggest that single crystals can provide spin-transport media with much less...

Abstract We demonstrate that the introduction of an elemental beam Mn during molecular epitaxial growth Bi 2 Se 3 results in formation layers MnSe 4 intersperse between pure . This study revises assumption held by many who magnetic topological insulators (TIs) incorporates randomly at Bi-substitutional sites Mn:Bi Here, we report thin film TI with stoichiometric composition grows a self-assembled multilayer heterostructure , where number separating single is approximately defined relative...

A systematic study of the uncertainties, sensitivity and limitations conductance technique for extracting interface state density tunneling dielectrics is presented. The methodology required to extract device parameters from capacitance data reviewed analyzed. effect uncertainties in on extracted was determined using experimental results thin oxides (1.4 nm 2.0 nm). Modeling used indicate effects various changes density. insulator equivalently minimal. series resistance increases with...

Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) films exhibit a complex structure of interconnected conductive PEDOT domains in an insulating PSS matrix that controls their electrical properties. This is modified by water rinse, which removes with negligible loss. Upon removal, film thickness reduced 35%, conductivity increased 50%, and prominent dielectric relaxation eliminated. These results suggest the removed not associated domain network substantially altered...

We report the direct measurement of Dirac point, Fermi level, and work function graphene by performing internal photoemission measurements on a graphene/SiO2/Si structure with unique optical-cavity enhanced test structure. A complete electronic band alignment at interfaces is accurately established. The observation from one-atom thick layer was possible taking advantage constructive optical interference in SiO2 cavity. yield found to follow well-known linear density-of-states dispersion...

In this work, high-performance top-gated nanowire molecular flash memory has been fabricated with redox-active molecules. Different molecules one and two redox centers have tested. The clean solid/molecule dielectric interfaces, due to the pristine self-assembly device self-alignment fabrication process. cells exhibit discrete charged states at small gate voltages. Such multi-bit in cell is favorable for high-density storage. These devices fast speed, low power, long retention, exceptionally...

Abstract Atomically precise fabrication has an important role to play in developing atom‐based electronic devices for use quantum information processing, materials research, and sensing. Atom‐by‐atom the potential enable control over tunnel coupling, exchange on‐site charging energies, other key properties of basic needed solid‐state computing analog simulation. Using hydrogen‐based scanning probe lithography, individual dopant atoms are deterministically placed relative atomically aligned...

Silicon nanowire (SiNW) field effect transistors (FETs) with channel widths down to 20 nm have been fabricated by a conventional "top-down" approach using electron-beam lithography. The SiNW device shows higher inversion current density than the control devices. extracted electron mobility of width (≈1000 cm2/Vs) is found be 2 times that reference MOSFET (≈480 large dimension (W ≥ 1 μm). We attribute this increase strain-induced changes in band structure after oxidation.

Aliphatic alcohols and aldehydes were reacted with the Si(111)-H surface to form Si-O-C interfacial bonds from dilute solution by using ultraviolet light. The resulting monolayers characterized transmission infrared spectroscopy, spectroscopic ellipsometry, contact angle measurements. effect of different solvents on monolayer quality is presented. best formed CH(2)Cl(2). optimized thoroughly determine film structure stability. UV-promoted, alcohol-functionalized, aldehyde-functionalized are...