Methods and Tehniques in Surface Science

1
Methods and Tehniques in Surface Science

Prof. Dumitru LUCA Alexandru Ion Cuza
University, Iasi, Romania
2
Introduction. Relation between surface/interface
science and other fields of knowledge

• What is the surface?
• How can the surface be probed?
• What kind of probing particles should be used?
• What kind of emergent particles can be detected?
• electrons, ions, low-energy neutrals
• 1-10 ML
• Scattered, absorbed, emitted particles the
  essential source of information.

3
Photon excitation

• HIGH penetration depth,
• but
• LOW probing depth when using non-photon emerging
  particles
• Photon sources
• Incandescent lamp
• Glow discharge lamp
• Lasers
• X-ray sources
• Sincrotron radiation

The spectrum of the electromagnetic radiation of
interest in surface science
4
Interaction of surface/interface science with
physics and engineering
Condensed matter physics
5
Countries where surface physics is performed
(source 1993, Briggs, Seah, see References)

• Journals
• 1 billion USD invested in1997
• 2500 set-ups

6
Relation between surface physics and various
industries (UK, 1997)
(source 1993, Briggs, Seah, see References)
7
Surface techniques and information that they
provide
8
Research strategies in surface science

• What is expected from surface physics?
• Making clear the mechanisms (at molecular/atomic
  levele) involved in a certain behavior of the
  surface.
• .HOWEVER.
• The surface theory is by far much simpler to
  develop for idealized surfaces (single crystals,
  clean surfaces or surfaces covered by adsorbants,
  in a controllable manner)
• Nowadays, we are able to develop theoretical
  models for tehnical surfaces at a satisfacory
  level.
• BUT
• The verifying the results predicted by the models
  is frequently not necessarily straightforward
• most of the surface techniques
  require using the UHV, while the real
  applications work at atmospheric pressure, and
  sometimes at high temperatures.

9
Research strategies in Surface Physics

• A complementary approach - measurements
• (a) in real time in situ (XRD, Moessbauer,
  infrared, EXAFS)
• (b) after quenching the investigated state.

Completing the above-mentioned information
via (i) modelling on single-crystals (ii)
using UHV techniques
10
Usual techniques in Surface Science

• 1. Temperature programmed techniques (TPD)
• 1a. Temperature programmed reduction (TPR)
• 1b. Temperature programmed sulphidation (TPS)
  catalysis
• 1c. Temperature programmed reaction spectroscopy
  (TPRS).
• 2. Photoemission spectroscopies
• 2a. X-ray Photoelectron spectroscopy (XPS)
• 2b. Ultraviolet photoelectron spectroscopy (UPS)
• - Auger Emission spectroscopy
• 3. Ion spectroscopies
• 3a. Low-energy ion scattering (LEIS)
• 3b. Secondary ion mass spectrometry (SIMS)
• 3c. Secondary neutral mass spectrometry (SNMS)
• 3d. Rutherford backscattering (RBS)

11
Usual techniques in Surface Science (contd)

• 4. Moessbauer spectroscopies
• 4a. Moessbauer Absorption Spectroscopy (MAS)
• 4b. Moessbauer Emission Spectroscopy (MES)
• 5. Diffraction methods X-Ray Diffraction (XRD),
  Low-Energy Electron Diffraction (LEED)
• and EXAFS (Extended X-ray Absorption Fine
  Structure).
• 6. Microscopy and si imagistics
• 6a. Transmission Electron Microscopy (TEM)
• 6b. Scanning Electron Microscopy (SEM)
• 6c. Electron Microprobe Analysis (EMA)
• 6d. Energy Dispersive X-ray Analysis (EDX/EDAX)
• 6e. Field Emission Microscopy (FEM)

12
Usual techniques in Surface Science (contd)

• 6f. Field Ion Microscopy (FIM)
• 6g. Atomic Force Microscopy (AFM)
• 6h. Scanning Tunneling Microscopy (STM)
• 6i. Photoemission Electron Microscopy (PEEM)
• 6j. Ellipsometry Microscopy for Surface Imaging
  (EMSI)
• 7. Vibration spectroscopies
• 7a. Infrared Spectroscopy (IS)
• 7b. Transmission Infrared Spectroscopy (TIS)
• 7c. Diffuse reflectance Infrared Spectroscopy
  (DRIS)
• 7d. Raman Spectroscopy
• 7e. Electron Energy Loss Spectroscopy (EELS)
• 8. Wettability, contact angle, Surface free
  energy
• 8a. Sessile drop static/dinamic measurements
  (advancing, receding angle)
• 8b. Hidrophobicity-hidrophilicity

13
References

• 1 H. P. Myers, Introductory Solid State
  Physics, TaylorFrancis, 1990 .
• 2 C. Desjonqueres, D. Spanjaard, Concepte de
  fizica suprafetei, Ed. Tehnica. 1998 (Romanian)
• 3 H. Lueth, Surfaces and interfaces of solid
  materials, Springer, 1993.
• 4 P. Atkins, J. de Paula, Physical Chemistry,
  Ed. 8, Oxford, 2006.
• 5 D. Briggs, M. P. Seah, Practical surface
  analysis, vol I, II, Willey and Sons, Ed. II
  1990.