Recent Advancements in Nanoscale IR Spectroscopy and Imaging Anirban Roy, Qichi Hu, Honghua Yang, Miriam Unger and Curtis Marcott Outline • Company Background • Introduction to AFM-IR • Latest AFM-IR Advancements • Resonance Enhanced AFM-IR • HyperSpectral Imaging/Spectroscopy • Tapping AFM-IR Imaging/Spectroscopy • Technical Overview • Applications • s-SNOM Technology and Applications • Tunable IR Laser Options • Summary 7/18/2019 Bruker Confidential 2 Bruker Nano Acquires Anasys Instruments • Bruker Nano Surfaces Division acquired Anasys Instruments Corp on April 10th 2018 • All nanoIR products are now integrated into the Bruker Nano Product Support 7/18/2019 Bruker Confidential 3 Nanoscale IR spectroscopy 2010 2014 2015 nanoIR™ nanoIR2™ nanoIR2-s™ 1st Generation 2nd Generation AFM-IR Combined AFM-IR Top Down Configuration & IR s-SNOM & AFM-IR Resonance Enhanced 2016 2017 2018 NEW nanoIR3™ Latest Generation nanoIR platform with Tapping AFM-IR nanoIR2-FS™ Tapping AFM-IR 3RD Generation HYPERspectra FASTspectra 7/18/2019 Bruker Confidential 4 Infrared Spectroscopy Introduction IR light wave IR Spectrum 1 = 0 2 ≠ 0 0 0 Source: Wikipedia Power and Limitations of Infrared Microspectroscopy FT-IR IR spectra Chemical Image IR microspectroscopy 2 PET applications 1.5 • Materials Science Tie Layer 1 • Consumer products EVOH Absorbance .5 • Pharmaceuticals 0 LDPE • Life sciences 1800 1600 1400 1200 1000 Wavenumber • Health & beauty Multilayer film, courtesy of Dr. Curtis Marcott • Forensics microscope IR microspectroscopy annual publications Abbe diffration limit: Practical resolution many microns AFM-Based IR Spectroscopy (AFM-IR) Alexandre Dazzi 2014 Ernst Abbe Award Ernst Abbe Time (ms) Dazzi, A.; Prazeres, R.; Glotin, F.; Ortega, J.M.; Opt. Lett. 2005, 30, 2388-2390. 7/18/2019 Bruker Confidential 7 Nanoscale IR Spectroscopy 7/18/2019 Bruker Confidential 8 nanoscale infrared imaging & spectroscopy capabilities Nanoscale IR Chemical composition & chemical analysis nanoscale property mapping Rich, interpretable Monolayer sensitivity & spectra high spatial resolution directly correlates to FTIR 7/18/2019 Bruker Confidential 9 Broad range of nanoIR applications Polymer blends & Multilayer films Nanofibers 2D Materials/Graphene Block Copolymers Organic nano Nano-Composites Life Science Perovskites & Contaminant nanoIR spectra s Solar Cells + + + 7/18/2019 Bruker Confidential 10 Resonance Enhanced Mode 7/18/2019 Bruker Confidential 11 Resonance Enhanced Mode Deflection signal laser signal Forced resonance makes AFM-IR more sensitive Laser repetition rate Single Monolayer Sensitivity F. Lu, M. Jin, and M.A. Belkin, Nat. Photonics 8, 307–312 (2013). Resonance enhanced AFM-IR of PEG monolayer Topography IR image at 1340 cm-1 CH2 wag C-O-C Asym CH2 scissor Purple Membrane (Resonance Enhanced AFM-IR) 3 x 4 μm Halobacterium Salinarum deposited on a Au substrate Amide Topography I Amide II 1 - IR Image IR cm 1540 at QCLs are getting faster! Single spectrum, 400 msec sweep, 0.2 msec time constant, no averaging 1.2 1 Anasys AFM-IR 100 msec 0.8 FTIR 0.6 0.4 Absorption (au) 0.2 0 1780 1580 1380 1180 980 780 Wavenumber (cm-1) Faster Scanning Enables Hyperspectral Imaging Hyperspectral image cube A B X C Y Figure 5. Illustration of the hyperspectral image cube. High speed AFM-based IR spectroscopy allow for the first time practical hyperspectral imaging, i.e., where spectra are mapped at matrix of XY points. One can extract segments of the hyperspectral cube to obtain (A) chemical maps that show spatial variation in absorption at a given wavelength, (B) spectral line maps showing the variation in spectra in one direction, or (C) individual spectra at any X,Y location. Hyperspectral animation 5-mm x 5-mm, 50 x 50 spectrum array on PS/PMMA/epoxy blend Move cursor onto above image and click on arrow to start animation Hyperspectral array PCA weight maps 5-mm x 5-mm, 50 x 50 spectrum array on PS/PMMA/epoxy blend AFM image PS PMMA Epoxy • New hyperspectral imaging provides point by point spectra over a large number of data points to provide an array of spectra and chemical images at specific wavenumbers • Principle component analysis can be applied to identify specific chemical components and their spatial distribution NEW nanoIR3 platform configurations nanoIR3™ - Latest Generation nanoIR platform with Tapping AFM-IR • Highest performance nanoIR spectra with AFM-IR • Sub-10nm resolution IR chemical imaging with Tapping AFM- IR • Correlates to FTIR & industry databases • Easy to use for fast, productive measurements nanoIR Spectroscopy of Polyethersulphone (PES) nanoIR3-s™ High Performance IR nano-spectroscopy • Complementary s-SNOM & Tapping AFM-IR • Highest Performance IR nano-spectroscopy • Broadband Spectroscopy & Chemical Imaging • Nanoscale property mapping • Versatility & Easy to Use Plasmonic Imaging on Graphene with Tapping AFM-IR & s-SNOM nanoIR3-s™ S-SNOM - High Performance s-SNOM Imaging • IR s-SNOM platform for optical & chemical Imaging • Supports multiple laser types, visible, nearIR s-SNOM imaging • Electrical nanoscale property mapping Phase and Amplitude • Upgradeable to nanoIR-spectroscopy on HbN 7/18/2019 Bruker Confidential 21 Sample Environmental Control Humidity control & heater & cooler • For control of humidity/gas & temperature for in-situ AFM-IR • 4% to 95% non condensing • 4°C to 80°C heating and cooling Sample transfer port for nanoIR3-s • Protects sample in controlled gas environment from glove box to nanoIR system to protect • includes integrated humidity sensor with optional high sensitivity humidity and oxygen sensors 7/18/2019 Bruker Confidential 22 IR Polarization Control & extended IR range Polarizer Option Optional & upgradeable 7/18/2019 Bruker Confidential 23 nanoIR nanoscale property mapping modes 7/18/2019 24 7/18/2019 Bruker Confidential 24 Tapping AFM-IR: Technical Overview Concept Zt : Distance of the Tip z Zs : Sample expansion (photothermal) t k/g : Linear/non-linear force constant zs as: Absorption coefficient at: Tip oscillation amplitude wp: Laser pulse rate wn: cantilever eigen mode frequency (n=1,2,3…) Fundamental 2nd Eigen mode Pulse mode n rate n Resonance Condition: w1 + wp = w2 n n 7/18/2019 Bruker Confidential 25 Tapping AFM-IR: Technical Overview Schematic Heterodyne Force Microscopy Signal M.T. Cuberes, J. Nanomater., 2009 Resonance Condition: /w2 w1 + wp = w2 7/18/2019 Bruker Confidential 26 Tapping AFM-IR: Key features • Broad Application range: - Hard/soft sample, Adhesives, Membranes, Particulates - Minimal sample/tip degradation due to absence of lateral forces • Improved Sensitivity: - Sensitivity enhanced by cantilever Q-factor – new probes - AFM detector with higher sensitivity - Efficient optical beam delivery optics with minimal loss • High Spatial Resolution: - Spatial resolution extends to ~10 nm or better • Multimodal Imaging: - Simultaneous chemical and viscoelastic property (Tapping Phase) imaging 7/18/2019 Bruker Confidential 27 Tapping AFM-IR: Applications Polymer 01: PEMA/PMMA Blend Tapping AFM-IR Spectra Height PEMA PMMA Tapping IR Image at 1026 cm-1 Sample courtesy: University of Minnesota 7/18/2019 Bruker Confidential 28 Tapping AFM-IR: Applications Polymer 02: PS/PMMA block copolymer 5 nm 2 x 2 um2 Tapping AFM-IR image at 1730 cm-1 highlights PMMA Observed spatial spheres embedded in PS resolution ~5 nm matrix Height Tapping IR Image Height -1 Sample courtesy: CEA-Leti at 1730 cm 7/18/2019 Bruker Confidential 29 Tapping AFM-IR: Applications Bio-pharmaceuticals 01: Skin/Dexamethasone Optical - Tapping AFM-IR image ratio at 1456/1740 cm-1 highlights the relative abundance of the drug in the lipophilic regions Amide I & II bands (bright yellow) Ester C=O from Proteins -CH2 bending in the Present in both drug and 1660 lipids 1532 1740 long chain lipids Height 1456 IR Image Ratio 1456/1740 Sample courtesy: FU Berlin 7/18/2019 Bruker Confidential 30 Tapping AFM-IR: Applications Bio-pharmaceuticals 02: Anti-cancer drug delivery • Paclitaxel, a power anti-cancer drug, suffers from low efficacy and side effects due to low water solubility/recrystallization • Recent study by Centrone and coworkers highlights the use of Tapping AFM-IR technology to explore the effect of different encapsulations in drug delivery • High resolution compositional sensitivity of this technique unfolds new developments of lipid-polymer hybrid films in drug delivery applications Centrone et al., Analyst, 2018, 143, 3808-3813 7/18/2019 Bruker Confidential 31 Tapping AFM-IR: Applications Organic Photovoltaics: TQ1/PC70BM Blend Height Acceptor (PC70BM) Donor (TQ1 polymer) IR Image Ratio 1598/1738 - Tapping AFM-IR spectra and images highlights the polymer rich matrix and PC70BM rich domains Sample courtesy: Karlstad University 7/18/2019 Bruker Confidential 32 Tapping AFM-IR: Applications 2D Materials: Graphene/Graphene Oxide - Tapping AFM-IR spectra and images show sensitivity to monolayer Graphene and Graphene Oxide Surface Plasmon Polariton (SPP) Liu et al., Carbon, 2018, 127, 141-148 Manuscript in prep 7/18/2019 Bruker Confidential 33 Tapping AFM-IR: Applications Failure Analysis: Organic Nanocontaminations “…Knowing why devices fail is a must Tapping AFM-IR Spectra when designing next-generation products..” V. Lakshminarayanan www.rfdesign.com, 2011 • AFM-IR technology complements traditional analytical tools used for failure analysis in nanoscale semiconductor FTIR Library Search devices/architectures • Enhanced sensitivity extends to samples with thickness <20 nm • Tapping AFM-IR technology demonstrates