Spectroscopy FNI 1 C 1 Spectroscopy Outputs Inputs

Spectroscopy FNI 1 C 1

Spectroscopy Outputs Inputs e- γ e- A+ γ A+ Sample FNI 1 C 2

Electrons Out Auger electrons Probe: Electrons Secondary electron imaging Backscattered electron imaging Transmitted electrons Electrons In e- e- Electron diffraction γ Photons out Energy Dispersive Spectroscopy Wavelength Dispersive Spectroscopy Sample FNI 1 C 3

Probe: Photons Out Photons In Infrared Visible Ultraviolet X-Rays γ Fourier Transform Infrared Spectroscopy Raman Visible Ultraviolet X-Ray Fluorescence X-Ray Diffraction γ Electrons Out XPS, X-ray Photoelectron Spectroscopy e- Sample FNI 1 C 4

Probe: Ions Out SIMS, Secondary Ion Mass Spectrometry Ions In To. F SIMS, Time of Flight SIMS, A+ A+ ICP MS, Inductively Coupled Plasma Mass Spectrometry Sample FNI 1 C 5

X-Ray Tools n X-Ray Spectroscopy ¨ Energy Dispersive X-ray Spectroscopy (EDS) ¨ Wavelength Dispersive X-ray Spectroscopy (WDS) X-ray fluorescence (XRF) n X-ray photoelectron spectroscopy (XPS) n X-Ray Diffraction n FNI 1 C 6

Energy Dispersive X-Ray Spectroscopy, EDS Element maps n Spectra n Applications n System overview n System image n X-Ray detector n FNI 1 C 7

EDS Applications n n n Used to determine the elemental composition of a sample. Can perform both qualitative (What is it? ) and quantitative (How much? ) analysis. Depending on the window low atomic number elements may not be visible. Super ultra thin windows detect down to berilium. Older detectors may only detect fluorine and higher. Window less detectors are available. FNI 1 C 8

FNI 1 C 9

FNI 1 C 10

EDS Element Map FNI 1 C 11

EDS Image FNI 1 C 12

Energy Dispersive X-Ray Detector System FNI 1 C 13

Solid state Si Li X-Ray Detector FNI 1 C 14

Example of Electron Transitions FNI 1 C 15

Vendors n EDAX http: //www. edax. com/index. html n Princeton Gamma Tech http: //www. pgt. com/ n Noran/Kevex/Thermo http: //www. thermo. com/BURedirect/welcome. Msg/1, 5107, 28, 00. html n Oxford Instruments http: //www. oxinst. com/ FNI 1 C 16

Wavelength Dispersive X-Ray Spectroscopy, WDS System Overview n Detector n Image n FNI 1 C 17

WDS System FNI 1 C 18

WDS Detector P 10 gas is 90% argon and 10% methane FNI 1 C 19

Image of WDS Detector FNI 1 C 20

Wavelength Dispersive X-Ray Spectroscopy System Overview n Detector n Image n FNI 1 C 21

Other X-Ray Analysis X-Ray Photoelectron Spectroscopy (XPS) n X-Ray Tomography Nano CT n XRD X-Ray Diffraction n FNI 1 C 22

X-Ray Photoelectron Spectroscopy An incoming X-Ray removes a core electron which will have a characteristic energy based on the difference between the initial X-Ray energy, which is of known energy, and the energy to remove the inner electron from the atom, which is characteristic. n This has very high sensitivity. n FNI 1 C 23

Links n n n http: //hyperphysics. phyastr. gsu. edu/hbase/quantum/hydazi. html#c 3 http: //elchem. kaist. ac. kr/vt/chem-ed/analytic/acmeths. htm http: //elchem. kaist. ac. kr/vt/chem-ed/scidex. htm http: //www. nanopicoftheday. org/ http: //www. physics. berkeley. edu/research/crommie/index. html FNI 1 C 24

Quantum Numbers Number Name Permitted Values Defines n Principal (1, 2, 3, …) Electron shell (1=K, 2=L, 3=M …) l Azimuthal 0 to n-1 Electron cloud shape m Magnetic -l to +l Electron shell orientation in a magnetic field s Spin ±½ Electron spin direction j Inner precession l±½ But j≠-½ Total angular momentum FNI 1 C 25

Electron Shells K LI LIII MI MIII MIV MV n 1 2 2 2 3 3 3 l 0 0 1 1 2 2 s +½ +½ -½ j ½ 1½ 1½ 2½ ½ ½ FNI 1 C ½ +½ 26

Electron Transitions 1. 2. 3. The change in n must be ≥ 1 (Δn ≠ 0) The change in l can only be ± 1 The change in j can only be ± 1 or 0 FNI 1 C 27

Other Surface Analysis Methods n Focused ion beam (FIB) n Mass spectrometry/Residual gas analyzer (Mass spec/RGA) Secondary ion mass spectrometry (SIMS) Time of Flight SIMS (To. F SIMS) Atom probe microscopy n n n n Auger electron spectroscopy (Auger or AES) Rutherford Backscattering Spectroscopy (RBS) Fourier transform infrared spectroscopy (FTIR) Raman spectroscopy FNI 1 C 28

Mass Spectrometry, Mass Spec n Residual Gas Analyzer, RGA n Sorts atoms, molecules and molecule fragments based on mass. n n http: //elchem. kaist. ac. kr/vt/chem-ed/ms/ms-intro. htm http: //elchem. kaist. ac. kr/vt/chem-ed/ms/mag-sect. htm http: //elchem. kaist. ac. kr/vt/chem-ed/ms/quadrupo. htm http: //elchem. kaist. ac. kr/vt/chem-ed/ms/tof. htm FNI 1 C 29

Secondary Ion Mass Spectrometry n n n http: //www. eaglabs. com/cai/simstheo/caistheo. htm http: //www. eaglabs. com/cai/simstheo/ionsput. htm http: //www. eaglabs. com/tutorial. htm FNI 1 C 30

SIMS FNI 1 C 31

To. F SIMS n http: //www. phi. com/genf. asp_Q_ID_E_283 FNI 1 C 32

Atom Probe Microscopes n http: //www. ornl. gov/info/ornlreview/rev 28 -4/text/atoms. htm n Imago Scientific Instruments http: //www. imago. com/imago/ FNI 1 C 33

Imago 3 D Atom Probe Microscope FNI 1 C 34

Imago LEAP FNI 1 C 35

Auger Electron Spectroscopy AES n http: //www. eaglabs. com/cai/augtheo/process. htm n AES has a number of advantages over X-Ray analysis. ¨ It can be confined to a very small spot. ¨ Signals are generated only from a very shallow depth into the sample (3 nm). ¨ It can be combined with an ion mill to create a very detailed analysis of bulk materials. ¨ Intermediate in price between SEM/EDS and more expensive systems. FNI 1 C 36

Rutherford Backscattering Spectroscopy, RBS n http: //www. eaglabs. com/cai/rbstheo/intro. htm n Uses alpha particles (He++) to analyze a material. FNI 1 C 37

Fourier Transform Infrared Spectroscopy FTIR Uses Infra-Red EM radiation to analyze molecules, especially organic compounds. Bending, stretching, rotation Infrared light of different energies is passed through the sample. How the sample absorbs light is analyzed. • http: //www. forumsci. co. il/HPLC/FTIR_page. html • http: //mmrc. caltech. edu/FTIRintro. pdf FNI 1 C 38

Raman Spectroscopy A change in polarizability of the molecule results in a shift in frequency of a laser. http: //carbon. cudenver. edu/public/chemistry/classes/chem 4538/raman. htm FNI 1 C 39

Focused Ion Beam FIB This method uses a beam of ions and magnetic lenses to focus the ions onto the sample. n FIB is used to drill tiny holes in a sample. n This is usually used to see the cross sectional structure of the device. n n http: //dsa. dimes. tudelft. nl/usage/technology/FIB/ http: //mfgshop. sandia. gov/1400_ext_Ion. Beam. htm http: //www. nanopicoftheday. org/2003 Pics/FIBNanofab. htm FNI 1 C 40

Example of FIB FNI 1 C 41

FIB Preparation for TEM FNI 1 C 42

FIB Links n n http: //www. ipr. umd. edu/ionbeam/ast-fib. html http: //cmm. mrl. uiuc. edu/techniques/fib. htm FNI 1 C 43

Links n n http: //hyperphysics. phy-astr. gsu. edu/hbase/quantum/hydazi. html#c 3 http: //elchem. kaist. ac. kr/vt/chem-ed/analytic/ac-meths. htm http: //elchem. kaist. ac. kr/vt/chem-ed/scidex. htm http: //www. nanopicoftheday. org/ FNI 1 C 44

Other Surface Analysis Methods n Focused ion beam (FIB) n Mass spectrometry/Residual gas analyzer (Mass spec/RGA) Secondary ion mass spectrometry (SIMS) Time of Flight SIMS (To. F SIMS) Atom probe microscopy n n n n Auger electron spectroscopy (Auger or AES) Rutherford Backscattering Spectroscopy (RBS) Fourier transform infrared spectroscopy (FTIR) Raman spectroscopy FNI 1 C 45