Surface Analysis
- 1. LEDN-02 Analysis Techniques Sample Probe Response Modified Probe Probe : photo Response : photo electron electron ion ion phonon phonon
- 2. Analysis Techniques phonon photo photo XRF, TXRF, FTIR, Raman electron electron ion ion phonon SIMS, RBS , ISS, GDMS ESCA EDS PIXE, GDOS SEM, TEM, AES, EELS LAMMA LEDN-03 Scanning Acoustic Microscopy
- 3. LEDN-004 Analysis Techniques Elemental Molecular Surface ( <10 Å) Thin film ( <100 Å - 1 m) Bulk ( > 10 m) Types of information provided by chemical analysis
- 4. LEDN-005 Surface and Thin film Analysis Surface Thin Film Elemental Molecular TXRF EDS RBS AES ESCA SIMS
- 5. 100% 100 ppm 1% 1 ppm XRF ESCA AES RBS SIMS EDX 100Å 10 µm 0.1 µm 1 µm 1 µm 0.1 µm 10 µm 100 µm 1 mm VD D E SENSITIVITY SPATIAL RESOLUTION QUANTITATION DEPTH RESOLUTION LEDN-006 SIMS vs. Other Techniques
- 6. LEDN-07 Analysis Principle Excitation Photoelectron E b = h -E k - Relaxtation ESCA EDS, XRF AES Auger electron KL 1 L 2,3 K (1s) L 1 (2s) L 2,3 (2s) Atom Ion e- h h
- 7. LEDN-08 Analysis Principle X-ray fluorescence (surface) Incident X-rays TRXF Depth information determined either by excitation depth or by escape depth 10-100 Å electron escape depth 1 m Electron excitation depth Auger electrons (surface) X-ray fluorescence Primary Electrons 10-100 Å electron escape depth 100-1000 m X-ray excitation depth photoelectrons (surface) X-ray fluorescence Incident X-rays
- 8. LEDN-09 Absorbed molecules Sputtered atoms SIMS Principle Sputtering event + + + Primary ions (~10 keV) Sample atoms + + - + + Secondary ions Mixing range (~100 Å) Escape range (~10 Å) Desorbed molecular ions
- 9. LEDN-10 SIMS Technique Schema ION SOURCE Sample MASS SPECTROMETER DETECTOR MASS SPECTRUM m DEPTH PROFILE X-Y IMAGE VACCUM m/q
- 10. Magnetic sector Quadrupole Time of Flight LEDN-11 SIMS Instrument Type r = k/B(m/q) 1/2 M- M M M+ M Vo(t) = Vc+Vs cos t t- t ~ M- M t ~ M t+ t ~ M+ M ion pulse Detection & Registration m/q ~ B m/q ~ V(f) m/q ~ t
- 11. << A = A Static SIMS Dynamic SIMS Primary ion dose <1E12 ions/cm2 >1E12 ions/cm2 Information Chemical Elemental Analysis Only surface Depth profile Instrument TOF & Quad Magnetic & Quad Ion damage section, Desorption area, D Bombarded surface, A LEDN-12 Dynamic vs. Static SIMS primary ion ion: elementa l information ion: molecular information
- 12. LEDN-13 Comparison of SIMS Instruments Magnetic Sector Quadrupole Time of Flight Transmission High (~10 -1 ) Low (~10 -3 ) High (~10 -1 ) Mass range Low (< 500) Low (< 600) Unlimited Mass resolution High ~ 10000 Low ~ 500 High ~ 10000 Detection speed Low High Quasi-parallel Charge compensation Difficult Easy Easy Analysis modes Bulk analysis Depth profiling (100Å-100 m) Imaging Bulk analysis Depth profiling (0Å-10 m) Imaging Surface Analysis Depth profiling (0Å-1 m) Imaging
- 13. Analytical Condition LEDN-14 Oxygen bombardment & Positive ions Cs bombardment & Negative ions Cs bombardment & Oxygen bombardment
- 14. LEDN-15 Detection Limits (atoms/cm3) in InP, GaAs, GaN For electropositive elements SIMS Detection Limit
- 15. LEDN-16 Detection Limits (atoms/cm3) in GaAs,InP and GaN For electronegative elements SIMS Detection Limit
- 16. Depth ( m) 1E13 at/cm3 LEDN-17 High Mass Resolution Analysis for P in Si High Sensitivity Concentration(at/cm3) P implantation in Si (2E12 atoms/cm2, 300 keV)
- 17. LEDN-18 Depth profiling of Multi-Quantum wells InGaAsP/InGaAs SIMS Depth Resolution Lz = 110 Å Lz = 125 Å
- 18. SiC fiber in a Ti matrix (V-doped) LEDN-19 Ti C Si V 50 m Ga + primary ion (30 keV, 50 pA) Ti + : 10s; Si + : 200s; V + : 100s; C + : 200s SIMS Image Analysis
- 19. SIMS Analysis for GaN LEDs LEDN-20 Enhance production yield Wafer Control LED wafers Test wafers Purity control (C,H,O,metals) Doping control (Si, Mg) Layer thickness (Growth rate) Interface quality Film composition (AlGaN,InGaN) SIMS analysis Calibration & Optimization of Growth GaN Epitaxy Growth Failure analysis Reverse engineering LED dies Reduce R&D cycle time
- 20. SIMS for AlInGaP LED LEDN-21 Depth (micron) Concentration (atoms/cm 3 ) AlInGaP
- 21. LEDN-22 SIMS for GaN LED Depth (micron) Concentration (atoms/cm 3 ) InGaN
- 22. SIMS for AlInGaP LD LEDN-23 Depth (micron) Concentration (atoms/cm 3 ) AlInGaP
- 23. SIMS for AlGaAs VCSEL LEDN-24 Depth (micron) Concentration (atoms/cm 3 ) VCSEL
- 24. SIMS for LED dies LEDN-25 GaN LED die SIMS craters AlInGaP LED die SIMS craters Doping concentration and distribution Undesirable Impurities Layer structure control Failure analysis Epi-layer structure p- and n-type metal stacks Passivation layers Reverse engineering
- 25. PL on the beveled surface SIMS profile Comparison between PL and SIMS LEDN-26 Composition Analysis by SIMS Al x Ga 1-x As composition by MCs + technique A B C D
- 26. Composition Analysis by Auger LEDN-27 Depth profiling of the top layers of GaN die