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Sample: SPP-PEOTapping mode in air30s/frame
High Speed AFM Imaging:
Survey, Screening, and Dynamicswith Bruker’s Revolutionary
FastScan Atomic Force Microscope
J.H. KindtJ.H. Kindt, N. Phan, S. Hu, F. Krainer,, N. Phan, S. Hu, F. Krainer,
L. Huang, L. Mininni, A. Slade, A. Mednick,L. Huang, L. Mininni, A. Slade, A. Mednick,
C. Su, and S.C. MinneC. Su, and S.C. Minne
Johannes H. Kindt, Ph.D.
Senior Applications ScientistBruker Corporation
For more information, please visit: www.bruker-axs.com/nanoconference
July 19 - AFM Tutorial, Bruker Nano Surfaces Business, Santa Barbara, USA
July 20-22 - Scientific Sessions, University of California, Santa Barbara, USA
Conference Chair: Prof. Paul Hansma, University of California, Santa Barbara,USAKeynote Speaker: Prof. Christoph Gerber, University of Basel, Switzerland
Session I — SPM in Biology and Life Science
Session Chair : Prof. Daniel MüllerInvited Speaker : Prof. Daniel Müller
Session II — Quantitative Nanoscale information: Structure and Physical Property Characterization of Nanomaterials
Session Chair : Prof. ZX ShenInvited Speakers : Prof. Thuc-Quyen Nguyen, Prof. ZX Shen and Prof. Joseph Lyding
Session III — Quantitative Nanoscale information
Session Chair : Prof. Robert CookInvited Speaker : Prof. Robert Cook
Session IV — Combination of SPM with Other Methods
Session Chair: Prof. Markus RaschkeInivted Speakers : Prof. Paul Weiss and Prof. Markus Raschke
Session V — Advances in SPM Instrumentation & Technology
Session Chair: Prof. Ania Bleszynski JayichInvited Speaker : Dr. Urs Duerig
Special Session — Tribute to Paul Hansma's Contributi on to the SPM Field
Invited Speaker : Prof. David Awschalom
5/25/2011 Bruker Nano Confidential 4
Outline
� History What is High Speed AFM?
� Motivation What is fast (and what is it good for)?
� Technology Bruker’s FastScan™ implementation
� FastScan™ at work Images and Movies
5/25/2011 Bruker Nano Confidential 5
What is High Speed AFM?
� There are many embodiments of High Speed AFM Systems.
� Often the capabilities of the systems are tailored for rapid advance in a specific application.
� Direct observation of molecular dynamics.
� Tapping Mode, Scan size up to 500nm, 7 frames per second.
Noriyuki Kodera, Daisuke Yamamoto, Ryoki Ishikawa, and Toshio Ando, "Video imaging of walking myosin V by high-speed atomic
force microscopy", Nature (Article) 468: 72-76 (2010).
Kanazawa University, Molecular Dynamics
5/25/2011 Bruker Nano Confidential 6
What is High Speed AFM?
� Most cited article in Surface Science 2005 – 2010 studying the adsorbtionand desorbtion of water and oxygen on TiO2
� Scan sizes of 10’s of nm, 10s of seconds per frame.
� STM Many of the same control issues, although a different sensing mechanism.
S. Wendt, R. Schaub, J. Matthiesen, E.K. Vestergaard, E. Wahlstrom, M.D. Rasmussen, P. Thostrup, L.M. Molina, E. Lægsgaard, I. Stensgaard, B. Hammer, F. Besenbacher,
“Oxygen vacancies on TiO2(110) and their interaction with H2O and O2: A combined high-resolution STM and DFT study”,
Surface Science 598 (2005) 226–245.
5/25/2011 Bruker Nano Confidential 7
What is High Speed AFM?
� Dynamic imaging of bacteriorhodopsinin Contact Mode.
� Scan sizes of ~700 nm, 10s frames per second.
Ignacio Casuso, Noriyuki Kodera, Christian Le Grimellec, Toshio Ando, and Simon Scheuring, “Contact-Mode High-Resolution
High-Speed Atomic Force MicroscopyMovies of the Purple Membrane,” Biophysical Journal Volume 97
September 2009 1354–1361
5/25/2011 Bruker Nano Confidential 8
What is High Speed AFM?
� Contact Mode imaging of collagen
� 2 um image on a system with 10’s of Microns scan range,
� 6 frames per second.
Advances in Fast AFM Technology, J.H. Kindt, G. Schitter, G.E. Fantner, P.J. Thurner, P. K. Hansma, invited talk at STM’05,
Sapporo, Japan
5/25/2011 Bruker Nano Confidential 9
What is High Speed AFM?
� Tapping Mode characterization of the initial stages of the action of the antimicrobial peptide in bacterial death.
� Micron scale images, 13s per frame.
Georg E. Fantner, Roberto J. Barbero, David S. Gray and Angela M. Belcher, “Kinetics of antimicrobial peptide activity measured
on individual bacterial cells using high-speedatomic force microscopy,” NATURE NANOTECHNOLOGY, VOL 5
(2010) 280.
5/25/2011 Bruker Nano Confidential 10
What is High Speed AFM?
� Improving the experience and
adding additional SPM capability
� Micron scale images, 15 frames per second
D M Carberry, L Picco, P G Dunton and M J Miles, “Mapping real-time images of high-speed AFM using multitouch control,”
Nanotechnology 20 (2009) 434018.
5/25/2011 Bruker Nano Confidential 11
Why High Speed AFM?
� Bandwidth enables:
• High Data Content
• High Tip Velocity
• No loss of resolution
• No increase of force
� A great AFM, faster.
• No loss of resolution
• No increase of force
• No added complexity
• No added operating cost
High Speed AFM
ResearchDevelopment
SurveyScreening Dynamics
0
2
4
6
8
10
12
5 10 15 20 25 30 35 40 45 50 55
Avg. domain size (nm)
# of samples
DNA-protein complexmovie courtesy
of Y. Lyubchenko
5/25/2011 Bruker Nano Confidential 12
Bandwidth: The Figure of MeritWhatever you want to do – only faster
� Plain English Definition:
• The comprehensive measure for comparing the speed difference, at identical performance (resolution and force), between two systems.
and the Technical Definition…
5/25/2011 Bruker Nano Confidential 13
Bottlenecks and Bandwidth
� The system is only as fast as its weakest link.
� Bandwidth (not tip velocity, or frame rate) is the fundamental metric.
Z drive
GainSetpoint Error
Cantilever motion
Laser
XY scan
Z
XY
1 10 100 1,000 10,000Frequency (Hz)
Response speed of elementsin feedback loop
1 frame/sec
1 10 100 1,000 10,000Frequency (Hz)
Response speed of elementsin feedback loop
1 frame/sec
5/25/2011 Bruker Nano Confidential 14
Full System Transfer Function
� The Transfer Function filters your image. What is filtered results in:• Missing spectral image components • Increased tip sample force.
� Certain sample characteristics challenge certain Elements.
5/25/2011 Bruker Nano Confidential 15
Full System Transfer FunctionEquivalent Tip-Sample Force
� High Speed AFM results >10x faster than a standard AFM
� Same image quality, same force control
Magnitude
Phase
Δf
Normal AFMFastScan™
(at equal tip-sample force)
5/25/2011 Bruker Nano Confidential 16
Key Element Detail: MechanicsBroadband™ Probes
� Probe Details
L (u
m)
W (
um
)
fr (
MH
z)
k (N
/m)
t (u
m)
Tip
He
igh
t
RO
C
TS
B
Ba
cksi
de
Co
atin
g
Style A 27 32 1.25 17 0.6Style B 30 32 0.40 4 0.3Style C 40 40 0.25 1.5 0.3
2.5 umto
8 um5 nm 5 Ηm Yes
1.57MHz 1.68MHzFr = 1.19M, Q = 201, k = 15
6e-26
0e-26
PSD
Typical Probe and Lorenz Best Fit
QkF ∝
QfrBW ∝
5/25/2011 Bruker Nano Confidential 17
-180
-90
0
90
180
Pha
se (
deg.
)
0.12 3 4 5 6 7 8 9
12 3 4 5 6 7 8 9
102 3 4 5 6 7 8 9
100
Frequency (kHz)
10
8
6
4
2
Am
plitu
de (
arb.
)0.1
2 3 4 5 6 7 8 91
2 3 4 5 6 7 8 910
2 3 4 5 6 7 8 9100
Frequency (kHz)
Key Element Detail: MechanicsZ Scanner
� Z-Scanner• Key speed element for rough samples.
• Requires simultaneous bandwidth and range.
• Z Scanner Performance:o Resonance > 50kHz
o Range > 3um
>10x
IconFastScan
5/25/2011 Bruker Nano Confidential 18
� Key Design Details
• Engineered Clamping and Probe Loading
• Designed Workflow and ScanAsyst Image Optimization
• Patented Cleaning accessory, for Fluid experiments
Key Element Detail: MechanicsZ Scanner
5/25/2011 Bruker Nano Confidential 19
A) Optical performance to navigate different samples
(semiconductor device, tissue section, ciliatae)
B) Positioning the Laser Spot on the Cantilever
� Motorized laser positioning
� Streamlined Software work flow
� Switch-selectable spot size, to accommodate all standard, Broadband, and even smaller probes
ba
Key Element Detail: Optics
5/25/2011 Bruker Nano Confidential 20
Key Element Detail: MechanicsXY Scanner
� XY-Scanner• The XY scanner is not in the feedback loop, however, its speed and dynamic response control the quality of the image.
� XY Scanner Performance:• Range > 30um range
• Resonance > 1kHz
• Bow < 3nm
4
3
2
1
Am
plitu
de (
arb.
)
0.12 3 4 5 6 7 8 9
12 3 4 5 6 7 8 9
10
Frequency (kHz)
Fast XFast Y
5/25/2011 Bruker Nano Confidential 21
100
80
60
40
20
0
Out
put (
V, a
rb.)
100x10-6806040200
Time (s)
Key Element Detail: Electronics
� Phase Lag:
• Contributes to the overall phase budget
• The NanoScope V is not bottleneck.
� Slew Rate:
• Slew rate ensures full bandwidth is usable over the entire displacement range (not just small movements).
• High Power amplifiers designed specifically for high speed AFM.
Meas. OutputDigital Step
5/25/2011 Bruker Nano Confidential 22
High Frame Rate Imaging
� Z Bandwidth – Rough Samples
� XY Bandwidth – Flat Samples
� Slew Rate – Tall Samples
� Probes – All areas of speed and resolution
� Ease-of-Use – Productivity and Resolution
Dry DNA – Tapping Mode1.5 um x 1.5 um, 512 x 512 pixels
66 um/s tip velocity22Hz scan rate, 24s/image
PerformanceScan range and stability
13 Seconds20um, 20 lines/s
5.3 Seconds2um, 48 lines/s
Scan Size.
1um
100nm
a
1024x1024 pixels20nm, 6.5 Lines/s.
157 Seconds
1nm
Stability.
c
5/25/2011 Bruker Nano Confidential 24
PerformanceResolution
SBS Copolymer
1 um x 1 um, 512 x 512 pixels 34 um/s tip velocity17Hz scan rate, 30s/imageScanAsyst
5/25/2011 Bruker Nano Confidential 25
PerformanceHOPG: Tapping Noise vs Speed
RMS
5/25/2011 Bruker Nano Confidential 26
PerformanceForce Control (abrasive samples)
Tip Check: Fractured Titanium
.5 um x 5um, 1024 x 1024 pixels 45 um/s tip velocity17Hz scan rate, ~1 frames/minTapping Mode Image
Polysilicon
2 um x 2um, 512 x 512 pixels88 um/s tip velocity22Hz scan rate, 24 s/imageTapping Mode Image
PerformanceForce Control and Tip Life
5
10
0 50 100 150 200Frame number
Est. Tip Radius. [nm]
ΔΔΔΔrTip (over 200 frames): 0.9nm →→→→
Tip Wear Rate: 4.5 Å/m
(each point represents rTip data from 25 frames)
1μμμμm
60 Seconds200 Frames, 1024 lines, 5um, 1 frame/min
5/25/2011 Bruker Nano Confidential 28
The FastScan™ Platform
�Platform Overview Dimension Icon Based Configuration
•Fast XYZ tip scanner with 30 um X 30 um X-Y range and >3 um Z rangeoScan speeds of 10x without quality loss (reference Icon, 512x512 at 1Hz)oScan speeds >100 Hz without scanner ringing
•Air or fluid operation
•8-channels with up to 5kX5K resolution
•High level programmability for unattended multiple sample scanning
•Dove-tail exchange with Icon head
5/25/2011 Bruker Nano Confidential 29
�Modes – Driven by NanoScope V
•ScanAsyst
•Quantitative Mapping
•TappingMode
•Contact mode
•Other common NanoScope modes.
�Probes
•High bandwidth cantilevers (>1MHz) to support faster scan speeds
•Dynamic laser-spot size adjustment to
support cantilevers of ~10um
The FastScan™ Platform
5/25/2011 Bruker Nano Confidential 30
Application Areas - Definitions
Survey: Explore unknown sample to understand its heterogeneity, characteristic features and properties.
Collect a representative set of images at publication quality.
� The Priority is a comprehensive understanding of the sample, and highest-quality image data.
� The end product is a representative set of high quality images.
Screening: Collect data on a statistically relevant number of sites on a known sample class.
Extract and Quantify specific, pre-determined metrics to represent sample variability within the class.
� The Priority is best possible throughput at adequate data quality.
� The end product is a statistics (histogram, graph,etc.).
Dynamics: Collect a series of images to follow a change of the sample over time. Select a sub-set of images that represent characteristic sample behavior.
� Time resolving the process takes priority over data quality.
� The end product is a movie that can be analyzed.
5/25/2011 Bruker Nano Confidential 31
8 Minutes per 16M pixel Image
20um, 16M pixel
2um
7.5um
One scan. All the detail.
(Phase)
(Height sensor)
Sample: PTFE
Data zoom
Surveythrough fast high resolution imaging
SurveyResult: High Quality publication data
60
0 0
40
nm °°°°
25 Seconds512x256 pixels, 10 lines/s
0.2μμμμm
Height Sensor
Phase
SPP PolymerTapping (Phase)Scan size: 2um15 lines/s30s/frame
5/25/2011 Bruker Nano Confidential 35
Screening: Amorphous FormulationBackground
Environmental stress testing and subsequent XRPD
detection of API crystals can take Weeks to Months.
AFM detectsSMALLER crystals EARLIER
(Hours - Days).
An AFM based stability assay can be predictive for XRPD
based stability testing.
Needed: Rapid Stability Detection“The .. problems that inhibit the use of the amorphous formulation are .. chemical/physical stability, .. not because of the stability itself but the difficulty in the timely evaluation in the preclinical developmental timeframes.”
Kawakami K., J Pharm Sci., 2009 Sep;98(9):2875-85
AFM Phase image of an amorphous formulation, after a few hours of aging.
Re-crystallizedAPI (10-20nm)
(Courtesy of M. Lauer, F.Hoffmann–La Roche)
5/25/2011 Bruker Nano Confidential 36
60 Minutes for entire data set(incl. Navigate, Engage, Capture, Withdraw)
Amorphous Drug Formulations.Samples courtesy of M.E. Lauer, O. Grassmann, F. Hoffmann-La Roche, Basel, Switzerland
12 Samples, 60 Sites. Automated.
Screening: Amorphous FormulationMiscibility & Stability screen
5/25/2011 Bruker Nano Confidential 37
DynamicsPolymer De-Wetting
Seeman et. al., J.Phys.: Condrnd. Matter 13 (2001) 4925.
Polystyrene De-wetting on Solid SubstratesSample courtesy of R. Seeman, Saarland University.
1.5 um x 1.5um, 45 um/s tip velocity15Hz scan rate, 35s/imageTapping Mode Image
5/25/2011 Bruker Nano Confidential 38
DynamicsBiomolecular Studies
1 Second per image(2100 Frames were captured at 1 frame per second)
DNA on Mica in Fluid (Prep by APS Method)Sample courtesy of Y. Lyubchenko, Univ. of Nebraska Med. Ctr.
nanoscaleworld.bruker-axs.com/nanoscaleworld/media/p/1559.aspx
5/25/2011 Bruker Nano Confidential 39
1 Second per image(2100 Frames were captured at 1 frame per second)
DNA on Mica in Fluid (Prep by APS Method)Sample courtesy of Y. Lyubchenko, Univ. of Nebraska Med. Ctr.
DynamicsBiomolecular Studies
5/25/2011 Bruker Nano Confidential 40
Conclusions
Dry DNA – TappingMode1.5 um x 1.5 um, 512 x 512 pixels
66 um/s tip velocity22Hz scan rate, 24s /image
� Bruker’s High Speed AFM Effort
• Increasing System Imaging Bandwidth 10x-100x
o No loss of resolution
o No increase of force
o No added complexity
o No added consumables cost
• Enables Higher Productivity and New Science
o Survey (Pan and Scan)
o Screening Application
o Dynamic Applications
July 19-22 at UC Santa Barbara, USA
For more information, please visit:www.bruker-axs.com/nanoconference
Early Bird registration ends on May 30th
REGISTER NOW!
www.AFMBiomed.org
Please take a minute for the exit survey.
For more information about FastScan™,please visit:
www.bruker.com/fastscan
contact me at:
Dr. Johannes H. [email protected] More Info: nanoscaleworld.bruker-axs.com
FastScan™ will be at these Bruker - sponsored conferences: