Combined AFM and Raman Enables: Comprehensive Data Using Optical, AFM, and Spectroscopic Methods

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1 Combined AFM and Raman Enables: Comprehensive Data Using Optical, AFM, and Spectroscopic Methods Dark field: sees cracks, and contamination: - Pick appropriate area for AFM scan AFM: real 3D morphology - Quantify roughness - Analyze grain size - Hole formation DIC: enhanced surface contrast: - distinguish between smooth and rough Raman: - identifies and localizes crystalline phase transition. The monoclinic => tetragonal phase transformation of Y-TZP results in surface roughening and occurs nonuniformly over the surface. Combined and colocalized AFM, RAMAN and DIC microscopy enables to study the process on the sub-micrometer lateral scale. 11/1/2011 Bruker NanoSurfaces Division 18

2 TERS Applications Overview: True Nanoscale Spectroscopy Targeted to Your Application Crystallography and optical properties of nanostructures (e.g., oxides and compound semiconductors) Chemical analysis of composite polymers (e.g., polymer blends) Single molecule dynamics Primary structure investigation (sequencing) in biopolymers In situ interrogation of biological molecules as an entry into more complex biological structures. Illustration reproduced from Chem Phys Letters 472 (2009) /1/2011 Bruker NanoSurfaces Division 19

3 TERS: Tip Enhanced Raman Scattering Enables Raman Spectroscopy Beyond the Diffraction Limit 3 setup possibilites Schematic from: 11/1/2011 Bruker NanoSurfaces Division 20

4 Geometry for Illumination k i kr Schematic diagram of the metal tip and substrate geometry: the tip is modeled as a conical taper terminated by a hemisphere of radius r, held at a distance d from the substrate surface. For discussion of SERS geometries see, e.g. : R. W. Rendell, D. J. Scalapino, Physical Review B 1981, 24, Z. Yang, J. Aizpurua, H. Xu, J. Raman Spectrosc. 2009, 40, A. Downes,D. Salter, A. Elfick, J. Phys. Chem. B 2006, 110, 11/1/2011 Bruker NanoSurfaces Division 21

5 Definitions of TERS Enhancement Contrast I with tip I without tip (a) EF = Contrast A focus A tip Contrast d 2 focus 2 d tip (c) Schmid et al. in Tip Enhancement (2007), Kawata & Shalaev (Eds). Contrast: 40, Enhancement Factor: ~ /1/2011 Bruker NanoSurfaces Division 22

6 Bruker s TERS enabled AFM-Raman: TERS-Ready AFM-Raman Integration Bruker Innova SPM Efficient direct optical coupling Raman sampling arm for side illumination and collection Renishaw invia Raman microscope 11/1/2011 Bruker NanoSurfaces Division 23

7 Bruker IRIS Integration Package: Highest Performance, Most Complete AFM Capabilities Hardware integration enables: Co-localised Raman SPM measurements TERS ready Operation of both instruments individually without any compromise in performance Easy alignment of Raman laser spot onto SPM tip Simple upgrade path from either an invia Raman microscope or Innova SPM Software integration allows: Automated Raman/SPM mapping using IRIS software module incl. simplified approach curve. Full use of Renishaw s WiRE software for Raman data analysis Full use of Nanoscope software for SPM data analysis 11/1/2011 Bruker NanoSurfaces Division 24

8 Optical Views of IRIS-Innova: Easy-to-Use Spectroscopy in Materials & Life Sciences Multiple cameras and trackball controlled objective positioning allow easy and precise alignment of Raman laser excitation source onto SPM tip Optical image of tip illuminated with Raman excitation laser. Taken with Innova optics Optical Image of tip with Raman excitation laser and IR AFM laser (IR filter removed). Taken along optical axis. 11/1/2011 Bruker NanoSurfaces Division 25

9 Malachite Green TERS: Proof of Performance on Innova IRIS Tip in feedback Tip retracted 50 nm Tip retracted 100 nm TERS tips courtesy of Sam Berweger and Markus Raschke, Univ.of Colorado 11/1/2011 Bruker NanoSurfaces Division 26

10 Customer Paper on TERS/SERS/Far-Field Advanced NanoScale Research on Bruker s Bioscope AFMs Collagen is the most abundant protein in the human body C. Gullekson, L. Lucas, K. Hewitt, L. Kreplak.Biophysical Journal 100(7), (2011) First step into understanding more complex biological objects Lateral resolution of TERS data <100nm TERS reveals peaks not identified in far-field Identifies individual secondary structures at the surface of collagen fibrils and proposes a specific orientation of exposed phenylalanine residues. 11/1/2011 Bruker NanoSurfaces Division 27

11 Single molecule sensitivity using side-on illumination and collection Ultimate Performance Malachite Green (AFM) BCB (STM) Neacsu, Dreyer, Behr, Raschke. Phys Rev B 73, (2006) Zhang, Yeo, Schmid, Zenobi. J. Phys. Chem. C, 111, (2007) 11/1/2011 Bruker NanoSurfaces Division 28

12 Conclusions: Integrated Systems Guarantee Optimum Performance Co-Localized Products for Seamless Integration of AFM and Optical Spectroscopy Highest Performance, Most Complete AFM Capabilities Nanoscale Material Mapping Co-located with Spectroscopy For Large or Small Transparent and Opaque Samples Integrated TERS-Enabled Systems for Material Sciences Best TERS-enabled AFM-Raman system integration available Easiest to use AFM for Spectroscopy in NanoStructured Materials Flexibility of analysis with every detail considered Innova Bioscope Catalyst Dimension Icon TERS, PF-QNM 11/1/2011 Bruker NanoSurfaces Division 29

13 apply innovation Renishaw / Bruker Raman AFM package Video camera for viewing sample and laser spot Renishaw AFM interface assembly

14 apply innovation AFM sample viewing objective AFM analytical module Objective for laser illumination and Raman signal capture

15 apply innovation Laser spot focused on sample