Scanning probe microscopes spm
Download
1 / 39

Scanning Probe Microscopes SPM - PowerPoint PPT Presentation

Scanning Probe Microscopes SPM History of scanning probe microscopes SPM System Overview Piezoelectric Effect Scanning Tunneling Microscope (STM) Atomic Force Microscope (AFM) Force vs. Distance Curve Scanning modes Vendors http://mechmat.caltech.edu/~kaushik/park/contents.htm

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

Scanning Probe Microscopes SPM

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Scanning Probe MicroscopesSPM

  • History of scanning probe microscopes

  • SPM System Overview

  • Piezoelectric Effect

  • Scanning Tunneling Microscope (STM)

  • Atomic Force Microscope (AFM)

  • Force vs. Distance Curve

  • Scanning modes

  • Vendors

  • http://mechmat.caltech.edu/~kaushik/park/contents.htm

FNI 1A


History of Scanning Probe Microscopes

  • Phonograph record

http://www.nanoworld.org/english/museum.html

FNI 1A


History of Scanning Probe Microscopes

  • 1929

  • Gustev Schmalz

  • Stylus profiler

FNI 1A


History of Scanning Probe Microscopes

  • 1971

  • Russel Young

  • Topographiner

  • A non-contact stylus profiler

FNI 1A


History of Scanning Probe Microscopes

  • 1981

  • Gerd Binnig & Heinrich Rohrer

  • Scanning Tunneling Microscope (STM)

FNI 1A


History of Scanning Probe Microscopes

  • Atomic Force Microscope (AFM/SFM)

  • Gerd Binnig, Calvin Quate & Christoph Gerber

  • 1986

FNI 1A


SPM System Overview

FNI 1A


SPM Scan Head

Non Contact AFM

STM

Force Modulation

AFM

Contact AFM

Lateral Force Microscopy

Laser should be switched on to operate

FNI 1A


SPM Scan Head

Second:

Adjust detector alignment until red lights are out and green light is on.

First:

Adjust cantilever alignment so laser is aligned on the cantilever

FNI 1A


Pre-Mounted AFM Probe Tip

FNI 1A


Cartridges

AFM Cartridge

STM Cartridge

FNI 1A


Digital Voltmeters

FNI 1A


Photodetector

Top = 1+2

1

2

Bottom = 3+4

3

4

A = 1+3

B = 2+4

LFM records Top-Bottom and should be minimized

A+B Should be Maximized

A-B Should be Minimized

FNI 1A


FNI 1A


FNI 1A


FNI 1A


FNI 1A


FNI 1A


Scanning Tunneling Microscope

  • Applications

  • System Components

  • Tube scanner

  • Piezoelectric effect

  • Theory of operation

  • Operating modes

  • Advantages & Disadvantages

FNI 1A


Applications

  • High resolution images at atomic resolution.

  • Ability to manipulate individual atoms.

  • http://www.almaden.ibm.com/vis/stm/gallery.html

FNI 1A


STM System Components

FNI 1A


Piezoelectric tube scanner

Piezoelectric materials are used to create a tube scanner. This forms one of the basic components of scanning probe microscopes.

These can be used to manipulate an object in three dimensions under electronic control.

FNI 1A


Piezoelectric Effect

Certain materials exhibit what is called the piezoelectric effect. (Demo)

This is an effect where changing the size of an object results in a voltage being generated by the object.

Conversely when a voltage is applied to a piezoelectric object then the size of the object changes.

FNI 1A


Piezoelectric Effect

PZT: Lead zirconium titanate is one of the most common piezoelectric materials.

Piezoelectric materials have an asymmetric unit cell like a dipole.

If these crystals are grown in the presence of a strong electric field then the crystal grains will align and the piezoelectric effect is created.

FNI 1A


Unit Cell with Dipole

The central atom is displaced resulting in a unit cell with a dipole moment.

Cubic

T > Tc

Tetragonal

T < Tc

FNI 1A


Piezoelectric EffectCrystal grains structure

Not grown in an electric field

Random orientation

Grown in an electric field

Unit cell dipoles align

FNI 1A


STM Theory of operation

Tunneling Current

FNI 1A


Scanning Tunneling Microscope

FNI 1A


Operating modes

  • Constant height mode

    • Current changes exponentially

    • Requires a smooth surface

  • Constant current mode

    • Beware of insulators

FNI 1A


STM Advantages & Disadvantages

  • Advantages

    • Able to obtain very high resolution images of conductors and semiconductors.

    • Probe tips can be made out of wire.

    • Inexpensive to purchase ~ $10,000

  • Disadvantages

    • Will not work with insulators.

    • If there are insulating materials present on the sample you can crash the tip.

    • Often need to be used under vacuum.

FNI 1A


Scanning Tunneling Microscope

  • Applications

  • System Components

  • Tube scanner

  • Piezoelectric effect

  • Theory of operation

  • Operating modes

  • Advantages & Disadvantages

FNI 1A


Atomic Force Microscope

  • System Components

  • Force vs. Distance

  • Performance & Images

  • Scanning Modes & Probe Tips

  • Vendors

FNI 1A


AFM System Components

Demo

FNI 1A


Force vs. Distance

FNI 1A


Performance

  • The piezoelectric tubes have a movement resolution of 1 nm/volt.

  • Magnifications of 5,000,000x can be achieved.

  • Resolution of 10 pm

  • Can operate in air and under liquids

  • Atomic force microscopes can be used on many different surfaces.

  • AFM is a versatile and easy to use tool.

  • Images http://www.nanoscience.com/

  • AFM Activity

  • WS 13

FNI 1A


Scanning Modes and Probe Tips

  • Standard probe tips

  • High resolution probe tips

  • Magnetic force microscopy

  • Frictional force microscopy/Lateral force microscopy

  • Elasticity/hardness measurements/Force modulation microscopy

  • Scanning Capacitance

  • Thermal scanning microscopy – two different metals/ thermo couple

  • Near-field Scanning Optical Microscopy/Light funnel

  • Piezoelectric cantilever

  • Electrostatic force microscopy

  • Dip pen nanolithography

  • Surface oxidation

  • Many different companies make probe tips for scanning microscopes.

FNI 1A


Veeco http://www.veeco.com/

JEOL http://www.jeol.com/

Nanoscience Instruments http://www.nanoscience.com/

Asylum Research http://www.asylumresearch.com/

JPK Instruments http://www.jpk.com/index2.htm

Molecular Imaging http://www.molec.com/

Nanofactory Instruments http://www.nanofactory.com/

Nanotec Electronica http://www.nanotec.es/

NT-MDT http://www.ntmdt.ru/

Quesant http://www.quesant.com/

WITec http://www.witec.de/

Pacific Nanotechnology http://www.pacificnanotech.com/

Nanoics Imaging http://www.nanonics.co.il/main/

Schaefer-TEC http://www.schaefer-tec.com/

Windsor Scientific http://www.windsor-ltd.co.uk/

LOT Oriel Ltd http://www.lot-oriel.com/uk/htm/all/home01.php

Atomic Force http://www.atomicforce.de/

Mikro Masch http://www.spmtips.com/

Surface Imaging Systems http://www.sis-gmbh.com/

Physik Instrumente http://www.polytecpi.com/

Accurion http://www.accurion.com/

Advanced Surface Microscopy http://www.asmicro.com/

Hysitron http://www.hysitron.com/

Infinitesima http://www.infinitesima.com/

Nanograph Systems http://www.nanographsystems.co.uk/

Nanonis http://www.nanonis.com/nanonis/avs/home/index.html

PSIA http://www.advancedspm.com/

Triple-O Microscopy http://www.triple-o.de/

Bioforce http://www.bioforcelab.com/

Scanning Probe Microscope Vendors

FNI 1A


Scanning Probe Microscopes

  • System Components

  • Force vs. Distance

  • Performance & Images

  • Scanning Modes & Probe Tips

  • Vendors

FNI 1A


Links

  • http://stm2.nrl.navy.mil/how-afm/how-afm.html

  • http://www.ikm.uni-karlsruhe.de/forschung/pzt_webseiten/eng/basics/ferro_main_eng.html

  • http://cst-www.nrl.navy.mil/lattice/struk/pzt_t.html

  • http://www.chembio.uoguelph.ca/educmat/chm729/STMpage/stmconc.htm

  • http://www.2spi.com/catalog.html

FNI 1A


ad
  • Login