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auger electrons ,[object Object],[object Object],[object Object],[object Object],E kin = E A - E B - E C K L K LL transition:

Auger animation E kin = E A - E B - E C

x-ray emission ,[object Object],[object Object],[object Object],E x-ray = E A - E B

Comparison K L Auger electron emission: K LL transition K L x-ray emission:

[object Object],Different transitions N 1-7 M 1-5 L 1-3 K 4s,4p 1/2 ,4p 3/2 ,4d 3/2 ,4d 5/2 ,4d 7/2 3s,3p 1/2 ,3p 3/2 ,3d 3/2 ,3d 5/2 2s,2p 1/2 ,2p 3/2 1s Splitting: K LL = K L 1 L 1 , K L 1 L 2 , K L 1 L 3 K L 2 L 3 , K L 2 L 2 , K L 3 L 3 K LL L MM M NN

Measurement ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Ag (2keV electrons incident)

Variation with element number ,[object Object],[object Object],[object Object],27 Co 28 Ni 29 Cu 775 eV 848 eV 920 eV L MM K LL N 1-7 M 1-5 L 1-3 K K LL L MM

Variation in periodic table ,[object Object],K LL M NN Energi of the strongest Auger transition for all elements: N 1-7 M 1-5 L 1-3 K K LL L MM M NN

Nomenclature ,[object Object],[object Object],[object Object],[object Object],Notation/transitions: (2S+1) L J S=  s L=  l J=  j 3s 1/2 M 1 ½ 0 3 3d 3/2 M 4 3x½ 2 3 2p 1/2 L 2 ½ 1 2 2p 3/2 L 3 3x½ 1 2 3p 3/2 M 3 3x½ 1 3 3p 1/2 M 2 ½ 1 3 3d 5/2 M 5 5x½ 2 3 2s 1/2 L 1 ½ 0 2 1s 1/2 K ½ 0 1 Spec. level X-ray level j l n 3 P 1 (-) 3 P 2 1 D 2 2s 2 p 4 K L 2,3 L 2,3 3 P 0 3 P 1 3 P 2 1 S 0 3 P 0 2s 1 p 5 K L 1 L 2,3 1 S 0 1 P 1 2s 0 2p 6 K L 1 L 1 Interme-diate End config. Transition

Magnesium K LL ,[object Object],N 1-7 M 1-5 L 1-3 K Splitting into 6 lines K LL = K L 1 L 1 , K L 1 L 2 , K L 1 L 3 , K L 2 L 3 , K L 2 L 2 , K L 3 L 3 + spin-orbit coupling (total 9 lines) K LL

Kinetic energy ,[object Object],[object Object],[object Object],[object Object],M 1-5 L 1-3 K K LL Initial state Final state Z E initial Z+1 E final1 Z+1 E final2

[object Object],[object Object],[object Object],[object Object],Producing the electrons Electron gun:

Measuring the electron energy ,[object Object],[object Object],[object Object],[object Object],[object Object],Cylindrical mirror analyser (CMA): V < 0  ,[object Object],[object Object],[object Object],Hemispherical Analyser (HSA): V 2 V 1 V 0 

Electron counter ,[object Object],[object Object],[object Object],[object Object],~2 cm

Energy of the strongest Auger transition ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],L MM K LL M NN

Change in surroundings L MM ~ L VV (V=valence band) K LL and plasmon losses C O ,[object Object]

Bulk and surface plasmons of Al Splitting into 6 Auger lines K LL = K L 1 L 1 , K L 1 L 2 , K L 1 L 3 , K L 2 L 3 , K L 2 L 2 , K L 3 L 3 Excitation of plasmons Bulk plasmons ~ 15 eV Surface plasmons ~11 eV ,[object Object],K L 1 L 2,3 K L 1 L 2,3 K L 1 L 1 K L 2,3 L 2,3

Oxidation to Al 2 O 3 K LL but NO plasmon losses (Al 2 O 3 is an isolator)

More fine structure ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

Qualitative analysis ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],Atomic number L MM K LL M NN Auger electron energy [eV]

What is this ? 529 eV 703 eV 848 eV

Stainless Steel! Cr 529 eV Fe 703 eV Ni 848 eV What is the composition?

Quantitative analysis ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],dz dI

[object Object],[object Object],Sensitivity factors K LL L MM M NN N 1-7 M 1-5 L 1-3 K K LL L MM M NN relative to Ag Relative Auger Sensitivities of the Elements

Composition of stainless steel ? ,[object Object],[object Object],Cr 529 eV Fe 703 eV Ni 848 eV I x /S x  i I i /S i

Handbook Cr S=0.3 Fe S=0.2 Ni S=0.28

Composition of stainless steel sample ,[object Object],[object Object],[object Object],Cr 529 eV Fe 703 eV Ni 848 eV

Other applications ,[object Object],[object Object],Attenuation of intensity: I = I  exp(-d/  ) ln(I/I   = (-1/  ) d  = -d / ln(I/I   I I 0 d 52 eV 1147 eV ~2 ML Assume (for Si): 1 ML ~ 1.5 . 10 15 1/cm 2 , thickness ~2 Å

Mean free path @ 52 eV: ~6 Å @ 1147 eV: ~13 Å

Identification of growth mode 2D: I/I  =  exp(-n . d/  ) 3D: I/I  =  (1-  ) +  exp(-m . d/  ) ...alloying! 2D 2D-3D 3D I I 0 d

Al/Pd/GaN Thin Film Example (cross section)

Al/Pd/GaN Atomic Concentration Data

Area Specific Depth Profile Example

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