AFM-IR for soft materials, including organics, polymers, composites and life sciences s-snom for hard materials including inorganics, semiconductors,

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1 s TM AFM-IR for soft materials, including organics, polymers, composites and life sciences s-snom for hard materials including inorganics, semiconductors, nanoantennas, graphene and other 2D materials True, model-free spectroscopic chemical analysis with AFM-IR not ambiguous material mapping Sub 2-nm spatial resolution mapping of complex optical properties and light-matter interactions (e.g. plasmon/phonon-polaritons) Proven ease of use and productivity on real world samples Powerful, full-featured AFM with standard imaging modes

2 AFM-IR and s-snom are complementary techniques for nanoscale imaging and spectroscopy. AFM-IR measures the absorbed light while s-snom measures scattered light. The nanoir2-s leverages all the features of the world leading nanoir2 platform, including AFM-based infrared spectroscopy (AFM-IR). The AFM-IR technique provides true, modelfree chemical spectra that depend only on the absorption properties of the sample. (Spectra obtained via other techniques depend on the complex optical properties of the tip and sample.) Using the AFM-IR technique, the Anasys nanoir2-s platform is capable of true chemical identification. This has led to its widespread adoption in a large number of soft matter applications such as polymer blends, thin films down to monolayers, interfaces, electrospun fibers, cells, bacteria, amyloids and many others. Some of the key AFM-IR features are: Model-free chemical identification with nanometer scale spatial resolution Accurate and interpretable IR spectra that can be used with commercial IR databases for chemical identification High sensitivity that enables spectroscopic measurements on ultra-thin films and monolayers Multifunctional, complementary measurements to enable correlation of structural, mechanical, thermal and chemical information at the nanometer scale AFM-IR provides true, model free spectroscopy, allowing rapid identification of chemical components with nanometer scale spatial resolution. 12 s-snom is the world s most powerful tool to study light-matter interactions and to map complex optical properties at the nanometer scale. This has application to compelling advanced materials including graphene, 2D materials, nanoparticles, and nanostructured antennas and phenomena including plasmons and phonon polaritons. Some of the key capabilities are: Sub-2 nm spatial resolution for mapping complex optical properties High resolution imaging and analysis of nano-optics/nanoantenna devices Nanometer scale characterization of near-field phenomena including plasmon-polariton and phonon-polariton Characterization of defects, carrier mobility and Fermi levels in graphene s-snom provides nanometer scale imaging of complex materials and optical phenomena

3 (left) uses the tip of the AFM to detect light absorbed by the sample. Absorbed light is converted to heat and rapid thermal expansion of the sample that is detected by the AFM tip. The thermal expansion as a function of wavelength (or wavenumber) is a direct measurement of the absorption spectrum of the region of the sample under the AFM-IR tip. This thermal expansion depends primarily on the sample s absorption coefficient k s and is largely independent of other optical properties of the tip and sample. The AFM-IR technique is thus preferred for measurements where an accurate absorption spectrum is desired. AFM-IR excels for soft matter which has high thermal expansion (examples in red circle, below right). Thermal expansion proportional only to sample absorption coefficient k s Scattered light depends on complex optical constants of tip and sample (right) detects light scattered by nanometer scale regions of the sample. The scattered field E s depends on the complex optical constants of both the tip and sample and contains rich information about nano-optical phenomena. Reference samples (e.g. gold or silicon) are usually employed to correct the measurements for unknown phase contributions from the light source and tip and sophisticated models may be needed to interpret the results. s-snom is a compelling technique for imaging nanoscale contrast in optical properties, with diverse applications in advanced materials, devices and fundamental light/matter interactions. s-snom works best for hard materials that interact strongly with light (examples in blue circle, above right.) photothermal induced resonance (PTIR) Together AFM-IR and s-snom enable measurements on an unprecedented range of samples Near-field optical microscopy infrared absorption tip-sample scattered light True, model free nanometer scale IR spectroscopy Soft matter including polymers, composites, organic thin films, biological cells, proteins, biopolymers, biominerals nanoscale imaging of complex optical properties and diverse light-matter interactions Hard matter including inorganics, semiconductors, graphene and other 2D materials, nanoantennas, plasmon-polariton/phonon-polaritons Yes, model free Approximate, model and sample dependent. Some peak shifts Yes via IR absorption Yes via scattered amplitude and phase Routine, including unknowns analysis Possible with known materials No Yes 2-1 nm Sub 2 nm (limited only by tip radius) ~1 min Minutes to hours, sample and source dependent Yes (absorption) Yes (scattered amplitude and phase) Yes (contact resonance) Yes (tapping phase) Yes (resonance enhanced mode) Yes

4 The AFM community has developed a universe of different imaging modes that provide material contrast, for example based on friction, dissipation, stiffness, etc. Although these techniques are each extremely useful, none of them provides unambiguous material identification. AFM-IR is the first technique that provides unambiguous material characterization for large classes of materials. AFM-IR (right) works by illuminating a sample with pulses of infrared radiation and using the tip of an AFM to detect the absorbed radiation with nanoscale spatial resolution. Specifically, IR light absorbed by the sample is converted to heat, causing a rapid thermal expansion pulse under the AFM tip, in turn exciting resonant oscillation of the AFM cantilever. The amplitude of the cantilever oscillation is directly proportional to the sample absorption coefficient. AFM-IR absorption spectra are created by measuring the cantilever oscillation amplitude as a function of the wavelength of the incident radiation. Each absorption peak corresponds to excitation of a specific molecular resonance and the pattern of peaks, i.e. the absorption spectrum act as a unique chemical fingerprint of a nanoscale region of the sample. AFM-IR schematic AFM-IR overcomes the limitations of the vast number of existing AFM-based imaging modes that provide ambiguous material contrast. Instead, AFM-IR provides true chemical identification. AFM-IR absorption spectra are direct measurements of sample absorption, independent of other complex optical properties of the tip and sample. As such, AFM-IR spectra correlate very well to conventional bulk IR spectra (right). Peak positions are highly accurate, enabling detailed analysis of band shapes, subtle peak shifts, secondary structure, orientation effects, etc. AFM-IR spectra are easily exported to third party chemical libraries (e.g., Bio-RAD s KnowItAll ) for rapid analysis and identification of unknown chemical components. AFM-IR provides nanometer scale absorption spectra with good correlation to bulk FTIR measurements. Anasys has recently introduced patented Resonance Enhanced Mode that has dramatically improved the sensitivity of the AFM-IR technique. Resonance Enhanced AFM-IR has demonstrated the ability to perform nanoscale IR spectroscopy on extremely thin films, including single polymer lamellae, self-assembled monolayers and biological membranes. AFM-IR measurements on 5 nm thick membrane of Halobacterium salinarum on Au substrate. (Left) AFM-IR point spectrum showing clear spectra from this ultra thin biological membrane. (Right Above) x 4 µm topographic image of membrane patches. (Right Below) Corresponding AFM-IR absorption map at 154 cm -1 showing protein distribution.

5 (yµ) 5 1 AFM-IR spectra (Left) across an interface (Right) in a carbon fiber/epoxy composite (Left) AFM-IR absorption spectra on PP (blue) and SiO 2 (red) components R: topography/composition map highlighting SiO 2 nanoparticle distribution in red.? ? -? -? - (yµ) 15 -? AFM-IR absorption spectra (left) and AFM image (right) near a crack in polyurethane tubing. AFM-IR spectra reveal nanoscale chemical insights into this material failure AFM-IR identified unknown polymer layers in a multilayer film. ILD ILD 2 28 AFM-IR absorption spectra (left) and AFM image (right) of the CH stretch band in a low K dielectric material AFM image (top left), AFM-IR absorption image (top right) and a resonance enhanced AFM-IR spectrum on single monolayer islands of PEG (yµ) AFM-IR spectra (left) and morphology (right) of a polymer blend across a rubber/nylon interface absorbance scaled at 114 cm -1 PMMA Protein bands phosphate band AFM-IR spectra reveal mineral/protein concentration and protein secondary structures in bone.

6 s-snom is a universal probe of light-matter interactions at the nanoscale. It is a powerful technique for mapping complex optical properties of materials and optical phenomena with nanometer scale spatial resolution. The s-snom technique uses a metallized AFM tip to enhance and scatter radiation from a nanometer scale region of the sample. The scattered radiation is detected in the far field, but it carries information about the complex optical properties of the nanoscale region of the sample under the metallized tip. Specifically, both the optical amplitude and phase of the scattered light can be measured. With appropriate models, these measurements can be converted into measurements of the complex optical constants (n, k) of the material under the tip. In some cases, the optical phase versus wavelength provides an approximation to a conventional absorption spectrum. The s-snom technique works best on hard materials, especially those with high reflectivity, high dielectric constants, and/or strong optical resonances. s-snom measurements can be made on some weakly scattering soft samples using longer acquisition times. cantilever probe scattered light incident beam AFM tip Infrared detector n s, k s Sample s-snom probes complex optical properties with nm scale spatial resolution Height A (Arb. u.) ø (rad) PMMA PS epoxy -.7 ø (rad) A (Arb. u.) Distance AFM image (bottom left), s-snom images at 1725 cm-1 (top right) and 1666 cm-1 (bottom right) highlighting the PMMA due to the its carbonyl absorption. µm The s-snom technique can provide exceptional spatial resolution in the range of 1-2 nm with a sharp tip. The s-snom technique has been used for several hundred scientific publications. Recent s-snom work using Anasys instrumentation has shown for example the ability to map defects, carrier mobility and Fermi levels in graphene (data shown above left, Gerber et al, PRL 214 in press) and map biological membranes (Berweger et al, JACS 21).

7 .9 A (Arb. u.) Height 8.9 ø (rad) A (arb. u.) ø (rad) distance s-snom images of surface plasmon polaritons (SPPs) in graphene. a) AFM height, b) s-snom amplitude; c) s-snom phase; d) cross-section of amplitude and phase across SPP standing waves. Graphene measurements courtesy of M. Raschke group, UC Boulder. AFM (top) and s-snom (bottom) images of a semiconductor device. The s-snom measurement clearly distinguishes metal, barrier film and low-k interlayer dielectric layers. AFM 162 cm cm SNOM amplitude AFM image (bottom left) and s-snom image (bottom center) of a bar antenna. The s-snom image reveals the dipole-like scattering from the bar antenna. Overlay image (top) showing s-snom image overlaid on topography SNOM phase 2 µm s-snom measurements of purple membrane reveal distribution of protein within the lipid membrane. Images in right column were taken with the IR source tuned to the amide I absorption band. Images in the left column collected away from the absorption band.

8 Anasys Instruments nanoir and nanoir2 have already been adopted by leading scientists at major research universities, government labs, and major international chemical/materials companies. The instruments have already generated dozens of scientific publications and more than a hundred scientific presentations. (See the growing list of nanoir publications at: The nanoir2-s builds on the easy to use nanoir2 platform with proven, patented innovations including: Rapid learning curve, proven productivity (users often generate publication quality results within a few days) Computer-controlled alignment and optimization of AFM-IR and s-snom signals Wavelength dependent beam steering to correct for beam deviations from tunable laser sources Dynamic, computer controlled beam attenuation, focus, and (optional) polarization Patented resonant enhanced mode for sensitivity down to the monolayer scale AFM-IR point spectra in around a minute Unambiguous material identification via AFM-IR spectra and commercial IR spectra databases The nanoir2-s is built on our full featured AFM with routinely used AFM imaging modes. These include tapping, phase, contact, force curves, lateral force, force modulation, EFM, MFM, CAFM and Anasys proprietary modes including nanothermal analysis and Lorentz Contact Resonance. (Please contact us to discuss which are standard and which are optional or discuss any other capabilities you may require.). Developed by Anasys Instruments, this award-winning technology uses Anasys ThermaLever probes to locally ramp the sample s temperature to measure and map thermal transitions and other thermal properties. Lorentz Contact Resonance (LCR) is a powerful and easy to use nanomechanical mapping technique. Broadband nanomechanical spectra provide rich information about variations in material stiffness, viscosity and friction. With just a few clicks you can rapidly determine optimal operating conditions that most efficiently discriminate components in complex heterogeneous materials and devices. LCR provides sensitive material contrast on materials ranging from soft polymers to hard inorganics and semiconductors. Call us today to discuss how we can help advance your research and development. 25 Chapala Street, Santa Barbara, CA 911 Phone: (85) 7-1 Fax: (85) 7- info@anasysinstruments.com