high speed afm imaging - bruker · pdf filehigh speed afm imaging: survey, screening, ......

Starting now…

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.

[email protected]

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


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



� 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.



� 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



� 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



� 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.



� 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.


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


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…


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


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.


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)


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 ∝


-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


� 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


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


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


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


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


PerformanceResolution

SBS Copolymer

1 um x 1 um, 512 x 512 pixels 34 um/s tip velocity17Hz scan rate, 30s/imageScanAsyst


PerformanceHOPG: Tapping Noise vs Speed

RMS


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


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


�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


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.


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


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)


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


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


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


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


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:

high speed afm imaging - bruker · pdf filehigh speed afm imaging: survey, screening, ......

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