Mechanical stress can drive chemical reactions and is unique in that the reaction product depend on both magnitude direction of applied force. Indeed, this directionality impossible through conventional means. However, unlike heat- or pressure-driven reactions, mechanical rarely isometrically, obscuring how inputs relate to force bond. Here we report an atomic microscope technique measure mechanically induced bond scission graphene real time with sensitivity atomic-scale interactions....

The past two decades have witnessed the emergence and rapid growth of research field nanoscale thermal transport. Much work in this has been fundamental studies that explored mechanisms heat transport films, wires, particles, interfaces, channels. However, recent years there an increasing emphasis on utilizing knowledge gained toward understanding improving device system performances. In opinion article, attempt is made to provide evaluation existing potential impacts basic efforts...

There is a significant need for chemical identification and imaging of nanofabricated structures devices, especially multiple materials integrated at the nanometer scale. Here we present nanofabrication, identification, nanometer-scale polymer nanostructures with better than 100 nm spatial resolution. Polymer polyethylene, polystyrene, poly(3-dodecylthiophene-2,5-diyl) were fabricated by tip-based nanofabrication. Nanometer-scale infrared measurements using atomic force microscopy...

Compared to relatively mature audio and video human-machine interfaces, providing accurate immersive touch sensation remains a challenge owing the substantial mechanical neurophysical complexity of touch. Touch sensations during relative lateral motion between skin-screen interface are largely dictated by interfacial friction, so controlling friction has potential for realistic mimicry surface texture, shape, material composition. In this work, we show large modulation finger locally...

We report exceptional nanoscale wear and fouling resistance of ultrananocrystalline diamond (UNCD) tips integrated with doped silicon atomic force microscope (AFM) cantilevers. The resistively heated probe can reach temperatures above 600 °C. batch fabrication process produces UNCD radii as small 15 nm, average radius 50 nm across the entire wafer. Wear tests were performed on substrates quartz, carbide, silicon, or UNCD. Tips scanned for more than 1 m at a scan speed 25 μm s−1 ranging from...

Atomic force microscope (AFM) cantilevers with integrated heaters enable nanometer-scale heat flow measurements, materials characterization, nanomanufacturing, and many other applications. When a heated AFM cantilever tip is in contact substrate, the interface hotspot whose temperature can be controlled over large range. Over past decade, there has been significant improvements understanding of flows within from an cantilever. There have also characterization calibration these cantilevers....

We demonstrate measurement and control of nanoscale single-asperity friction by using cantilever probes featuring an in situ solid-state heater contact with silicon oxide substrates. The temperature was varied between 25 790 °C. By a low thermal conductivity sample, oxide, we are able to vary tip temperatures over broad range from ± 2 255 In ambient atmosphere ∼30% relative humidity, the forces achieved through formation capillary bridge whose characteristics exhibit strong dependence on...

Infrared (IR) spectroscopy is one of the most widely used techniques for identifying and characterizing materials, but diffraction limited to a spatial resolution no smaller than several micrometers. This paper reports IR with 100 nm resolution, using tunable laser whose absorption in an organic layer measured via atomic force microscopy. Wavelength-dependent sample results local thermomechanical deformation, which sensed sharp tip resonant microscope cantilever. We introduce cantilever...

We demonstrate measurement and control of single-asperity friction by using cantilever probes featuring an in situ solid-state heater. The heater temperature was varied between 25 650 °C (tip temperatures from ± 2 to 120 20 °C). Heating caused increase a factor 4 air at ∼30% relative humidity, but dry nitrogen decreased ∼40%. Higher velocity reduced ambient with no effect nitrogen. These trends are attributed thermally assisted formation capillary bridges the tip substrate air, sliding...

We investigate the nanometer-scale flow of molten polyethylene from a heated atomic force microscope (AFM) cantilever tip during thermal dip-pen nanolithography (tDPN). Polymer nanostructures were written for temperatures and substrate controlled over range 100–260 °C while was either moving with speed 0.5–2.0 µm s−1 or stationary 0.1–100 s. find that polymer depends on surface capillary forces not shear between substrate. The mass rate is sensitive to temperature-dependent viscosity....

Although aligned arrays of single-walled carbon nanotubes (SWNTs) have outstanding potential for use in broad classes advanced semiconductor devices, the relatively large population metallic SWNTs (m-SWNTs) that results from conventional growth techniques leads to significantly degraded performance. Recently reported methods based on thermocapillary effects enable removal m-SWNTs such offer exceptional levels efficiency, but procedures are cumbersome and require multiple processing steps....

Driving and measuring chemical reactions at the nanoscale is crucial for developing safer, more efficient, environment-friendly reactors surface engineering. Quantitative understanding of in real operating environments challenging due to resolution environmental limitations existing techniques. Here we report an atomic force microscope technique that can measure reaction kinetics driven by multiphysical stimuli ambient environment. We demonstrate local reduction graphene oxide as a function...

We measure the infrared spectra of polyethylene nanostructures height 15 nm using atomic force microscope spectroscopy (AFM-IR), which is about an order magnitude improvement over state art. In AFM-IR, light incident upon a sample induces photothermal expansion, measured by AFM tip. The thermomechanical response sample-tip-cantilever system results in cantilever vibrations that vary time and frequency. A time-frequency domain analysis vibration signal reveals how dynamics affect AFM-IR...

Phase change materials offer thermal energy storage (TES) and are often integrated with high conductivity to increase power density. However, the design optimization of such composites historically based on intuition, as computational techniques used predict behavior in these systems generally too expensive perform parametric studies. Herein, a general framework is developed demonstrated that optimized for TES parallel lamellar structures, identify critical pitch required treat composite...

We report measurements of near-field absorption in heavily silicon-doped indium arsenide microparticles using atomic force microscope infrared spectroscopy (AFM-IR). The exhibit an peak at 5.75 μm, which corresponds to a localized surface plasmon resonance within the microparticles. agree with far-field transmission and reflection, results numerical solutions Maxwell equations. AFM-IR single microparticle show temperature increase expected from Ohmic heating particle, highlighting potential...

The crystallization of amorphous germanium telluride (GeTe) thin films is controlled with nanoscale resolution using the heat from a thermal AFM probe. dramatic differences between and crystalline GeTe phases yield embedded features strong topographic, electronic, optical contrast. flexibility scanning probe lithography enables width depth features, as well extent their crystallization, to be by varying temperature write speed. Together, these technologies suggest new approach nanoelectronic...

With the commercialization of haptic devices, understanding behavior under various environmental conditions is crucial for product optimization and cost reduction. Specifically, surface dependence friction force electroadhesion effect on relative humidity finger hydration level can directly impact their design performance. This article presents influence finger-surface Mechanisms including changes to Young's modulus skin, contact angle change capillary were analyzed separately with...

This paper presents methodology to quantitatively link the macroscale ball mill reaction parameters fundamental drivers of chemical reactivity using a novel reactor with precise force control and integrated measurement.

We investigate the control of tip temperature on feature size during dip-pen nanolithography (DPN) mercaptohexadecanoic acid (MHA) Au. Heated atomic force microscopy (AFM) probes operated between 25 °C and 50 wrote nanostructures MHA for various dwell times speeds. The exhibited an exponential dependence with apparent activation barrier 165 kJ/mol. Analysis ink transfer process shows that, while ∼1/3 is from dissolution into meniscus, rest reflects to adsorption onto growing feature, a that...

Atomic force microscope infrared spectroscopy (AFM-IR) can perform IR spectroscopic chemical identification with sub-100 nm spatial resolution, but is relatively slow due to its low signal-to-noise ratio (SNR). In AFM-IR, tunable laser light incident upon a sample, which results in rise temperature and thermomechanical expansion of the sample. An AFM tip contact sample senses this nanometer-scale photothermal expansion. The motion induces cantilever vibrations, are measured either terms...

The authors report fabrication of arbitrary shapes silicon and oxide nanostructures using tip-based nanofabrication (TBN). A heated atomic force microscope (AFM) tip deposits molten polymer on a substrate to form that serve as etch mask fabricate or nanostructures. demonstrate how TBN can be combined with conventional wet etching well metal-assisted chemical etching, in order these size the TBN-fabricated is around 200 nm. Silicon fabricated have very smooth sidewalls with, roughness small 2...

We describe an atomic force microscope cantilever design for which the second flexural mode frequency can be tailored relative to first frequency, operation in contact with a substrate. A freely resonating paddle internal reduces stiffness of while nearly maintaining mass original cantilever. Finite element analysis is used predict performance various designs and several cantilevers are fabricated tested. This strategy allows ratio two resonant modes f2/f1 controlled over range 1.6–4.5. The...