Probes used for analysis Electron Photon Neutron Ui

Probes used for analysis • Electron • Photon • Neutron Ui. O IFE Waves/particles Wave length Amplitude and phase Coherence Monochromatic 16/1 -13 MENA 3100

What to learn about • Imaging/microscopy • Spectroscopy – Visible light/Optical – Electron – EDS • X-rays – EELS • SEM • STEM • TEM • Electrons – XPS, AES Different imaging modes. • Electrons (surface) Mapping of elements or chemical states of elements. • Diffraction – X-rays – Electrons – Neutrons The same basic theory for all waves. 16/1 -13 • Sample preparation – – MENA 3100 Mechanical grinding/polishing Chemical polishing/etching Ion bombardment Crunching etc……

Waves and lenses r 2 α r 1 α Spherical aberration r 2 r 1 Chromatic aberration S 1 S 2 v - Δv v Back focal plane x Object f Thin lens 1. image y http: //www. physicsclassroom. com/class/refrn/u 14 l 5 f. cfm 16/1 -13 MENA 3100 Astigmatism y-focus x-focus

Probe-specimen interactions Probe dependent • Wave length dependence electron – Diffraction • Z- and structure dependence photon – Scattering factors • Orientation dependence • Energy dependent neutron – Ineleastic scattering/ energy transfere 16/1 -10 MENA 3100

Basic principles, electron probe Electron Auger electron or x-ray Valence M M 3 d 6 3 p 4 3 d 4 2 p 2 Electron shell L 3 s 2 2 2 p 4 3 p 2 s 2 K L 1 s 2 K Secondary electron 19/1 -10 Characteristic x-ray emitted or Auger electron ejected after relaxation of inner state. Low energy photons (cathodoluminescence) when relaxation of outer stat. MENA 3100

Basic principles, x-ray probe X-ray Auger electron Valence Secondary x-rays M M Electron shell L K Photo electron 16/1 -10 Characteristic x-ray emitted or Auger electron ejected after relaxation of inner state. Low energy photons (cathodoluminescence) when relaxation of outer stat. MENA 3100

Probes • Photon Visible light • – Optical microscopy (OM), Ch. 1 X-ray – X-ray diffraction (XRD), Ch. 2 – X-ray photo electron spectroscopy (XPS), Ch. 7 • Neutron – Neutron diffraction (ND) (IFE) 16/1 -13 MENA 3100 Electron – Scanning electron microscopy (SEM), Ch. 4 – Transmission electron microscopy (TEM), Ch. 3 – Electron diffraction (ED), Ch. 3 – Electron energy loss spectroscopy (EELS) – Energy dispersive x-ray spectroscopy (EDS), Ch. 6 – Auger electron spectroscopy (AES), Ch. 7

Basic principles X-rays Electrons (SEM) BSE X-rays (EDS) SE AE (XPS) AE PE SE E=Eo E<Eo (EELS) (TEM and ED) 16/1 -13 MENA 3100 (XD) X-rays You will learn about: - the equipment -imaging -diffraction -the probability for different events to happen -energy related effects -element related effects -etc. , etc……. .