Basic XPS Information Section

 The Basic XPS Information Section provides fundamental XPS spectra, BE values, FWHM values, BE tables, overlays of key spectra, histograms and a table of XPS parameters.
The Advanced XPS Information Section is a collection of additional spectra, overlays of spectra, peak-fit advice, data collection guidance, material info,
common contaminants, degradation during analysis, auto-oxidation, gas capture study, valence band spectra, Auger spectra, and more.
Published literature references, and website links are summarized at the end of the advanced section.
 Periodic Table – HomePage                 XPS Database of Polymers                    → Six (6) BE Tables



Titanium (Ti)

 

Ilmenite – FeTiO3 Titanium – Tio Rutile – TiO2

 

  Page Index
  • Pure Element Spectra with Peak-fits
  • IMFP and Cross-sections for Pure Element
  • Native Oxide Spectra with Peak-fits
  • Pure Oxide Spectra with Peak-fits
  • Overlays and Valence Band Spectra
  • Six (6) Tables of Chemical State BEs 
  • Histograms of NIST BEs
  • Advanced XPS Information Section
  • Peak-fits and Overlays of Ti Chemical Compounds
  • Quantitation and Atom %s
  • Flood Gun Effects on Native Oxide Spectra
  • Study of UHV Gas Capture after Cleaning
  • Auger Peaks and Spectra
  • Contamination
  • XPS Facts, Guidance, Information
  • Chemical State Spectra from Literature
  • Expert Knowledge & Explanations


Titanium (Tio) Metal
Peak-fits, BEs, FWHMs, and Peak Labels


 

Titanium (Tio) Metal
Ti (2p) Spectrum – raw spectrum

ion etched clean

 

Titanium (Tio) Metal
Peak-fit of Ti (2p) Spectrum (w/o asymm)
using 2p3/2 to 2p1/2 peak area ratio for peak-fit



 Periodic Table – HomePage  
Titanium (Tio) Metal
Ti (2p) Spectrum

Titanium (Tio) Metal
Peak-fit of Ti (2p) Spectrum (w asymm)

 

Survey Spectrum of Titanium (Tio) Metal
with Peaks Integrated, Assigned and Labelled


 Periodic Table 

XPS Signals for Titanium (Tio) Metal

Spin-Orbit Term,  BE (eV) Value, and Scofield σ for Aluminum Kα X-rays (1486 eV, 8.33 Ang)

Overlaps Spin-Orbit Term BE (eV) Value Scofield σ from 1486 eV X-rays IMFP (TPP-2M) in Å
Ti (2s) 561 3.24 20.2
Ti (2p1/2) 461 2.69 21.9
Ru (3p) & In (3d) overlap Ti (2p3/2) 453.9 5.22 21.9
Na (2s) overlaps Ti (3s) 59 0.473 28.2
Ti (3p) 33 0.813 28.6

σ:  abbreviation for the term Scofield Photoionization Cross-Section which is used with IMFP and TF to generate RSFs and atom% quantitation

Energy Loss Peaks

Auger Peaks

Energy Loss Peak:  ~18 eV above peak max
Expected Bandgap for TiO22 : 3.2 eV 

*Scofield Cross-Section (σ) for C (1s) = 1.0

 


 

Ti (3p) Spectrum from Titanium (Tio) Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching

Ti (3p) Spectrum – Raw data Ti (3p) Spectrum – Peak-fit (w/o asymm)

 


 

Valence Band Spectrum from Titanium (Tio) Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching


 

Plasmon Peaks from Titanium (Tio) Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching

Ti (2p) – Extended Range Spectrum Ti (2p) – Extended Range Spectrum – Vertically Zoomed

 

Ti (KLL) Auger Peaks from Titanium (Tio) Metal
 Fresh exposed bulk produced by extensive Ar+ ion etching

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 


 

Artefacts Caused by Argon Ion Etching

Titanium Carbide(s)

can form when ion etched Reactive Metal Surfaces capture
Residual UHV Gases (CO, H2O, CH4 etc)

Argon Trapped in Tio

can form when Argon Ions are used
to removed surface contamination


 

Side-by-Side Comparison of
Ti native oxide & Titanium Dioxide (TiO2)
Peak-fits, BEs, FWHMs, and Peak Labels

Ti native oxide TiO (Rutile, single crystal)
Ti (2p) from Ti native oxide
Flood Gun OFF
As-Measured, C (1s) at 285.2 eV 
Ti (2p) from TiO2 – exposed bulk of Rutile, single crystal
Flood Gun ON
Charge Referenced to C (1s) at 285.0 eV

 Periodic Table 

.
C (1s) from Ti native oxide
on Titanium
As-Measured, C (1s) at 285.2 eV  (Flood Gun OFF)
C (1s) from TiO2 – exposed bulk of Rutile single crystal
Flood Gun ON
Charge Referenced to C (1s) at 285.0 eV



 Periodic Table 
O (1s) from Ti native oxide
on Titanium
As-Measured, C (1s) at 285.2 eV  (Flood Gun OFF)

O (1s) from TiO2 – exposed bulk of Rutile single crystal
Flood Gun ON
Charge Referenced to C (1s) at 285.0 eV


.
Ti (KLL) Auger Peaks from Ti metal ion etched
Flood Gun ON
Charge Referenced to C (1s) at 285.0 eV

Ti (KLL) Auger Peaks from TiO2 – exposed bulk of Rutile single crystal
Flood Gun ON
Charge Referenced to C (1s) at 285.0 eV



 

Survey Spectrum of Titanium (Ti) Native Oxide
with Peaks Integrated, Assigned and Labelled

 Periodic Table 


 

Survey Spectrum of Titanium Di-oxide, TiO2
with Peaks Integrated, Assigned and Labelled


 Periodic Table  



Overlays of Ti (2p) Spectra for
Titanium Tio metal, Ti native oxide, and TiO(Rutile)
Caution: BEs from Grounded Native Oxides can be Misleading if Flood Gun is ON

 Overlay of Tio metal and Ti native oxide – Ti (2p)
Native Oxide C (1s) = 285.2
 Overlay of Tio metal and TiO2 – Ti (2p)
Pure Oxide C (1s) = 285.0 eV
Chemical Shift:  4.5 eV
 
 Periodic Table  Copyright ©:  The XPS Library 

 

Overlay of Ti (2p)
Tio Metal, Ti native oxide, & TiO2 

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 


 

Valence Band Spectra
Tio, TiO2  (Rutile)

Tio
Ion etched clean
TiO2 – Rutile single crystal – exposed bulk
Flood gun is ON,  Charge referenced so C (1s) = 285.0 eV

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 



 

Titanium Minerals, Gemstones, and Chemical Compounds

 

Anatase – TiO2 Titanium Fluoride (sputter target) – TiF3 Perovskite – CaTiO3 Geikielite – MgTiO3

 Periodic Table 



 

Six (6) Chemical State Tables of Ti (2p3/2) BEs

 

  • The XPS Library Spectra-Base
  • PHI Handbook
  • Thermo-Scientific Website
  • XPSfitting Website
  • Techdb Website
  • NIST Website

 Periodic Table 



 

Notes of Caution when using Published BEs and BE Tables from Insulators and Conductors:

  • Accuracy of Published BEs
    • The accuracy depends on the calibration BEs used to calibrate the energy scale of the instrument.  Cu (2p3) BE can vary from 932.2 to 932.8 eV for old publications 
    • Different authors use different BEs for the C (1s) BE of the hydrocarbons found in adventitious carbon that appears on all materials and samples.  From 284.2 to 285.3 eV
    • The accuracy depends on when the authors last checked or adjusted their energy scale to produce the expected calibration BEs
  • There are uncertainties and error ranges in nearly all BEs 
    • Flood guns 
  • Worldwide Differences in Energy Scale Calibrations
    • For various reasons authors still use older energy scale calibrations 
    • Some authors still adjust their energy scale so Cu (2p3/2) appears at 932.2 eV or 932.8 eV because this is what the maker taught them
    • This range causes BEs in the higher BE end to be larger than expected 
    • This variation increases significantly above 600 eV BE
  • Charge Compensation
    • Samples that behave as true insulators normally require the use of a charge neutralizer (electron flood gun with or without Ar+ ions) so that the measured chemical state spectra can be produced without peak-shape distortions or sloping tails on the low BE side of the peak envelop. 
    • Floating all samples (conductive, semi-conductive, and non-conductive) and always using the electron flood gun is considered to produce more reliable BEs and is recommended.
  • Charge Referencing Methods for Insulators
    • Charge referencing is a common method, but it can produce results that are less reliable.
    • When an electron flood gun is used, the BE scale will usually shift to lower BE values by 0.01 to 5.0 eV depending on your voltage setting. Normally, to correct for this flood gun induced shift, the BE of the hydrocarbon C (1s) peak maximum from adventitious carbon is used to correct for the charge induced shift.
    • The hydrocarbon peak is normally the largest peak at the lowest BE. 
    • Depending on your preference or training, the C (1s) BE assigned to this hydrocarbon peak varies from 284.8 to 285.0 eV.  Other BEs can be as low as 284.2 eV or as high as 285.3 eV
    • Native oxides that still show the pure metal can suffer differential charging that causes the C (1s) and the O (1s) and the Metal Oxide BE to be larger
    • When using the electron flood gun, the instrument operator should adjust the voltage and the XY position of the electron flood gun to produce peaks from a strong XPS signal (eg O (1s) or C (1s) having the most narrow FWHM and the lowest experimentally measured BE. 

 Periodic Table 


Table #1

Ti (2p3/2) Chemical State BEs from:  “The XPS Library Spectra-Base”

C (1s) BE = 285.0 eV for TXL BEs
and C (1s) BE = 284.8 eV for NIST BEs

Element Atomic # Compound As-Measured by TXL or NIST Average BE Largest BE Hydrocarbon C (1s) BE  Source
Ti 22 Ti – element 453.8 eV 285.0 eV The XPS Library
Ti 22 Ti-Si 454.1 eV 285.0 eV The XPS Library
Ti 22 TiB2 (N*1) 454.4 eV 284.8 eV Avg BE – NIST
Ti 22 Ti-Ni 454.5 eV 285.0 eV The XPS Library
Ti 22 Ti-C 454.8 eV 455.0 eV 285.0 eV The XPS Library
Ti 22 Ti-P (N*1) 454.8 eV 284.8 eV Avg BE – NIST
Ti 22 Ti-N 454.9 eV 455.4 eV 285.0 eV The XPS Library
Ti 22 Ti-O (N*2) 455.1 eV 455.9 eV 284.8 eV Avg BE – NIST
Ti 22 TiS2 (N*1) 456.2 eV 284.8 eV Avg BE – NIST
Ti 22 Ti-2O3 (N*3) 456.8 eV 456.9 eV 284.8 eV Avg BE – NIST
Ti 22 Ti-O2 458.0 eV 458.8 eV 285.0 eV The XPS Library
Ti 22 K2Ti4O9 458.1 eV 285.0 eV The XPS Library
Ti 22 SrTiO23 (N*1) 458.1 eV 284.8 eV Avg BE – NIST
Ti 22 CaTiO3 458.2 eV 285.0 eV The XPS Library
Ti 22 SrTiO3 458.4 eV 285.0 eV The XPS Library
Ti 22 M-TiO3 (N*5) 458.5 eV 458.9 eV 284.8 eV Avg BE – NIST
Ti 22 CaTiO3 (N*1) 458.9 eV 284.8 eV Avg BE – NIST
Ti 22 Ti-Fx 459.2 eV 459.6 eV 285.0 eV The XPS Library

Charge Referencing

  • (N*number) identifies the number of NIST BEs that were averaged to produce the BE in the middle column.
  • Binding Energy Scale Calibration expects Cu (2p3/2) BE = 932.62 eV and Au (4f7/2) BE = 83.98 eV.  BE (eV) Uncertainty Range:  +/- 0.2 eV
  • Charge Referencing of insulators is defined such that the Adventitious Hydrocarbon C (1s) BE (eV) = 285.0 eV.  NIST uses C (1s) BE = 284.8 eV 
  • Note:   Ion etching removes adventitious carbon, implants Ar (+), changes conductivity of surface, and degrades chemistry of various chemical states.
  • Note:  Ion Etching changes BE of C (1s) hydrocarbon peak.
  • TXL – abbreviation for: “The XPS Library” (https://xpslibrary.com).  NIST:  National Institute for Science and Technology (in USA)

 Periodic Table 


Table #2

Ti (2p3/2) Chemical State BEs from:  “PHI Handbook”

C (1s) BE = 284.8 eV

 Periodic Table 

Copyright ©:  Ulvac-PHI


Table #3

Ti (2p3/2) Chemical State BEs from:  “Thermo-Scientific” Website

C (1s) BE = 284.8 eV

Chemical state Binding energy (eV)
Ti (2p3/2)
Ti metal 454.1
TiN 454.9
TiO2 458.5
SrTiO3 458.4

 Periodic Table 

Copyright ©:  Thermo Scientific 


Table #4

Ti (2p3/2) Chemical State BEs from:  “XPSfitting” Website

Chemical State BE Table derived by Averaging BEs in the NIST XPS database of BEs
C (1s) BE = 284.8 eV

 Periodic Table 

Copyright ©:  Mark Beisinger


Table #5

Ti (2p3/2) Chemical State BEs from:  “Techdb.podzone.net” Website

 

XPS Spectra – Chemical Shift | Binding Energy
C (1s) BE = 284.6 eV

XPS(X線光電子分光法)スペクトル 化学状態 化学シフト ケミカルシフト

Element Level Compound B.E.(eV) min max
Ti 2p3/2 Ti 454.0 ±0.3 453.7 454.2
Ti 2p3/2 TiB2 454.4 ±0.2 454.2 454.5
Ti 2p3/2 TiO2 455.1 ±0.3 454.8 455.3
Ti 2p3/2 TiN 455.8 ±0.2 455.6 456.0
Ti 2p3/2 Metallocene 456.3 ±0.9 455.4 457.2
Ti 2p3/2 TiCl4 458.5 ±0.2 458.3 458.7
Ti 2p3/2 BaTiO3 (cubic,tetra.) 458.5 ±0.2 458.3 458.7
Ti 2p3/2 PbTiO3 458.6 ±0.2 458.4 458.8
Ti 2p3/2 CaTiO3 458.8 ±0.2 458.6 459.0
Ti 2p3/2 SrTiO3 458.8 ±0.2 458.6 459.0
Ti 2p3/2 TiO2 459.0 ±0.4 458.6 459.3

 

 Periodic Table 



 
 

Histograms of NIST BEs for Ti (2p3/2) BEs

Important Note:  NIST Database defines Adventitious Hydrocarbon C (1s) BE = 284.8 eV for all insulators.

Histogram indicates:  453.9 eV for Tio based on 8 literature BEs Histogram indicates:  458.7 eV for TiO2 based on 12 literature BEs

Table #6


NIST Database of Ti (2p3/2) Binding
Energies

NIST Standard Reference Database 20, Version 4.1

Data compiled and evaluated
by
Alexander V. Naumkin, Anna Kraut-Vass, Stephen W. Gaarenstroom, and Cedric J. Powell
©2012 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Important Note:  NIST Database defines Adventitious Hydrocarbon C (1s) BE = 284.8 eV for all insulators.

Element Spectral Line Formula Energy (eV) Reference
Ti 2p3/2 [Ti(C7H7)(C5H5)] 455.40  Click
Ti 2p3/2 Ti[Co(CN)6] 458.60  Click
Ti 2p3/2 Ti[Ir(CN)6] 458.60  Click
Ti 2p3/2 Ti[Rh(CN)6] 458.50  Click
Ti 2p3/2 [TiCl(C5H5)2] 455.80  Click
Ti 2p3/2 TiB2 454.40  Click
Ti 2p3/2 TiC 454.90  Click
Ti 2p3/2 TiCl4 458.50  Click
Ti 2p3/2 TiCl4 459.80  Click
Ti 2p3/2 TiCl4 458.50  Click
Ti 2p3/2 TiCl4 459.80  Click
Ti 2p3/2 [TiCl2(C5H5)2] 457.10  Click
Ti 2p3/2 TiO2 459.20  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.80  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 TiO2 458.33  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 459.20  Click
Ti 2p3/2 TiO2 459.60  Click
Ti 2p3/2 TiO2 458.00  Click
Ti 2p3/2 TiO2 458.75  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 459.20  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.80  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 TiO2 458.33  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 459.20  Click
Ti 2p3/2 TiO2 459.60  Click
Ti 2p3/2 TiO2 458.00  Click
Ti 2p3/2 TiO2 458.75  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 459.20  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.80  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 TiO2 458.33  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 459.20  Click
Ti 2p3/2 TiO2 459.60  Click
Ti 2p3/2 TiO2 458.00  Click
Ti 2p3/2 TiO2 458.75  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 CaTiO3 458.87  Click
Ti 2p3/2 Ti2O3 457.80  Click
Ti 2p3/2 BaTiO3 458.52  Click
Ti 2p3/2 BaTiO3 458.55  Click
Ti 2p3/2 PbTiO3 458.58  Click
Ti 2p3/2 SrTiO3 458.80  Click
Ti 2p3/2 TiO 455.10  Click
Ti 2p3/2 TiO 455.90  Click
Ti 2p3/2 TiO 454.60  Click
Ti 2p3/2 TiP 454.80  Click
Ti 2p3/2 TiS 455.40  Click
Ti 2p3/2 Ti 454.00  Click
Ti 2p3/2 Ti 454.30  Click
Ti 2p3/2 Ti 454.00  Click
Ti 2p3/2 Ti 453.20  Click
Ti 2p3/2 Ti 454.00  Click
Ti 2p3/2 Ti 454.00  Click
Ti 2p3/2 Ti 454.07  Click
Ti 2p3/2 Ti 453.89  Click
Ti 2p3/2 Ti 453.80  Click
Ti 2p3/2 Ti 453.73  Click
Ti 2p3/2 Ti 454.00  Click
Ti 2p3/2 Ti 454.07  Click
Ti 2p3/2 Ti 453.94  Click
Ti 2p3/2 SrTiO3 458.10  Click
Ti 2p3/2 TiO/NiTi 454.60  Click
Ti 2p3/2 Ti2O3 456.90  Click
Ti 2p3/2 TiO2/NiTi 458.40  Click
Ti 2p3/2 TiO2/NiTi 459.00  Click
Ti 2p3/2 Ni0.86TiO1.86 455.00  Click
Ti 2p3/2 Ni0.86TiO1.86 456.50  Click
Ti 2p3/2 Ni0.86TiO1.86 458.50  Click
Ti 2p3/2 NiO0.25 + TiO1.59 455.30  Click
Ti 2p3/2 NiO0.25 + TiO1.59 456.90  Click
Ti 2p3/2 NiO0.25 + TiO1.59 458.50  Click
Ti 2p3/2 TiO1.5 456.80  Click
Ti 2p3/2 TiO1.5 458.50  Click
Ti 2p3/2 TiO1.5 455.20  Click
Ti 2p3/2 BaTiO3 457.90  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.90  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.30  Click
Ti 2p3/2 TiO2 458.30  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.30  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 459.10  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.80  Click
Ti 2p3/2 TiO2 458.74  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 458.20  Click
Ti 2p3/2 TiO2 458.50  Click
Ti 2p3/2 TiO2 459.30  Click
Ti 2p3/2 TiO2 458.80  Click
Ti 2p3/2 TiO2 458.70  Click
Ti 2p3/2 TiO2 459.10  Click
Ti 2p3/2 TiO2 458.90  Click
Ti 2p3/2 TiO2 458.51  Click
Ti 2p3/2 TiN 455.80  Click
Ti 2p3/2 TiN 455.20  Click
Ti 2p3/2 TiN 454.92  Click
Ti 2p3/2 TiN 454.92  Click
Ti 2p3/2 TiN 454.95  Click
Ti 2p3/2 TiN 455.40  Click
Ti 2p3/2 TiN 454.77  Click
Ti 2p3/2 TiN 455.17  Click
Ti 2p3/2 TiN 455.50  Click
Ti 2p3/2 TiN 455.80  Click
Ti 2p3/2 TiN 455.20  Click
Ti 2p3/2 TiN 454.92  Click
Ti 2p3/2 TiN 454.92  Click
Ti 2p3/2 TiN 454.95  Click
Ti 2p3/2 TiN 455.40  Click
Ti 2p3/2 TiN 454.77  Click
Ti 2p3/2 TiN 455.17  Click
Ti 2p3/2 TiN 455.50  Click
Ti 2p3/2 PbTiO3 458.80  Click
Ti 2p3/2 PbTiO3 457.80  Click
Ti 2p3/2 PbTiO3 457.50  Click
Ti 2p3/2 PbTiO3 458.70  Click
Ti 2p3/2 SrTiO3 458.20  Click
Ti 2p3/2 TiSi2 453.90  Click
Ti 2p3/2 TiSi2 453.10  Click
Ti 2p3/2 TiSi2 453.10  Click
Ti 2p3/2 (TiO2)82(SiO2)18 458.50  Click
Ti 2p3/2 TiO2 458.60  Click
Ti 2p3/2 TiO2/Al2O3 459.30  Click
Ti 2p3/2 (TiO2)56(SiO2)44 458.60  Click
Ti 2p3/2 (TiO2)24(SiO2)76 459.20  Click
Ti 2p3/2 (TiO2)14(SiO2)86 459.20  Click
Ti 2p3/2 Ta1.4Ti98.6 454.00  Click
Ti 2p3/2 Ti2S3 459.00  Click
Ti 2p3/2 Ta1.4Ti98.6Ox 459.20  Click
Ti 2p3/2 TiS2 458.70  Click
Ti 2p3/2 TiS2 456.10  Click
Ti 2p3/2 TiS2 457.30  Click
Ti 2p3/2 TiS2 456.20  Click
Ti 2p3/2 TiOx/Ti 460.20  Click
Ti 2p3/2 TiN0.12 454.30  Click
Ti 2p3/2 TiN0.24 454.50  Click
Ti 2p3/2 TiN0.72 454.80  Click
Ti 2p3/2 TiN0.96 454.80  Click
Ti 2p3/2 TiN1.01 455.00  Click
Ti 2p3/2 TiN1.19 455.00  Click
Ti 2p3/2 Ti2O3 456.80  Click
Ti 2p3/2 TiOx/Nb/Si 459.20  Click
Ti 2p3/2 Al54Cu2Ti44Ox 458.20  Click
Ti 2p3/2 Al54Cu2Ti44Ox 458.40  Click
Ti 2p3/2 Al54Cu2Ti44Ox 459.00  Click
Ti 2p3/2 TiOS 456.50  Click
Ti 2p3/2 TiOS 457.60  Click
Ti 2p3/2 TiOS 458.80  Click
Ti 2p3/2 TiOS 456.50  Click
Ti 2p3/2 TiOS 457.40  Click
Ti 2p3/2 TiOS 458.90  Click
Ti 2p3/2 TiO0.3S1.5 456.30  Click
Ti 2p3/2 TiO0.3S1.5 457.50  Click
Ti 2p3/2 TiO0.3S1.5 458.80  Click
Ti 2p3/2 TiO0.3S1.5 456.30  Click
Ti 2p3/2 TiO0.3S1.5 457.50  Click
Ti 2p3/2 TiO0.3S1.5 458.90  Click
Ti 2p3/2 Al3Ti 453.30  Click
Ti 2p3/2 AlTi3 453.80  Click
Ti 2p3/2 O2/Ti 454.20  Click
Ti 2p3/2 PbTiS3 456.10  Click
Ti 2p3/2 TiF4 461.10  Click
Ti 2p3/2 Zr0.85Ti1.15O4 458.10  Click
Ti 2p3/2 Zr0.85Ti1.15O4 458.30  Click
Ti 2p3/2 TiN0.09O0.74 454.90  Click
Ti 2p3/2 TiN0.31O0.44 455.00  Click
Ti 2p3/2 TiN0.54O0.17 455.00  Click
Ti 2p3/2 TiN0.63O0.08 455.00  Click
Ti 2p3/2 TiN0.7 454.80  Click
Ti 2p3/2 TiN0.75 455.00  Click
Ti 2p3/2 TiN0.81 455.00  Click
Ti 2p3/2 Zr1.09Ti0.91O4 458.20  Click
Ti 2p3/2 Zr1.09Ti0.91O4 458.30  Click
Ti 2p3/2 TiO0.73 454.50  Click
Ti 2p3/2 TiO0.9 454.70  Click
Ti 2p3/2 TiO2 458.80  Click
Ti 2p3/2 TiO2 459.00  Click
Ti 2p3/2 AlTi 453.70  Click
Ti 2p3/2 Al56Cu7Ti37Ox 458.40  Click
Ti 2p3/2 Al56Cu7Ti37Ox 459.00  Click
Ti 2p3/2 BaZr0.5Ti0.5O3 458.20  Click
Ti 2p3/2 ZrTiO4 458.80  Click
Ti 2p3/2 ZrTiO4 458.50  Click
Ti 2p3/2 TiN/Ti 455.50  Click
Ti 2p3/2 Al56Cu7Ti37Ox 458.20  Click
Ti 2p3/2 SrTiO3 458.10  Click
Ti 2p3/2 SrTiO3 457.60  Click
Ti 2p3/2 SrTiO3 458.20  Click
Ti 2p3/2 TiO2/SiO2 459.60  Click
Ti 2p3/2 TiN/SiO2 454.92  Click
Ti 2p3/2 NiTiO3 458.70  Click
Ti 2p3/2 Al48Ti52 453.80  Click
Ti 2p3/2 (-Ti(OCH(CH3)2)x(C4H9C(O)O)y(O-)z)n 458.90  Click
Ti 2p3/2 Ti(OCH(CH3)2)4 458.57  Click
Ti 2p3/2 Ti/Ta 454.10  Click
Ti 2p3/2 TiN0.9 455.17  Click
Ti 2p3/2 TiN0.9 454.77  Click
Ti 2p3/2 CaTiSiO5 459.60  Click
Ti 2p3/2 La2TiO5 458.20  Click
Ti 2p3/2 Na2Ti2Si2O9 459.70  Click
Ti 2p3/2 Ti3(PO4)4.nH2O 458.80  Click
Ti 2p3/2 BaTiSi3O9 460.10  Click
Ti 2p3/2 Pb28.60Ti10.16La5.47O55.77 458.45  Click
Ti 2p3/2 TiN0.81 455.10  Click
Ti 2p3/2 TiN0.92 455.10  Click
Ti 2p3/2 TiO2/K 459.00  Click
Ti 2p3/2 TiO2/K 458.30  Click
Ti 2p3/2 TiO2/K 458.50  Click
Ti 2p3/2 TiO2/K 458.60  Click
Ti 2p3/2 [C9H16C5H3]2TiCl2 456.80  Click
Ti 2p3/2 [C5H8C5H3]2TiCl2 456.81  Click
Ti 2p3/2 [C7H12C5H3][C10H55]TiCl2 456.81  Click
Ti 2p3/2 TiCl3 458.50  Click
Ti 2p3/2 [C5H8C5H3][C5H5]TiCl2 457.00  Click
Ti 2p3/2 [C5H8C5H3][C5H5]TiCl2 456.96  Click
Ti 2p3/2 (PbS)1.18(TiS2)2 457.30  Click
Ti 2p3/2 [(C5H5)2]TiCl2 457.29  Click
Ti 2p3/2 LiTiS2 456.40  Click
Ti 2p3/2 ((PbS)1.18(TiS2)2))0.85(Co(C5H5)2)0.15 457.30  Click
Ti 2p3/2 Al2TiO5 458.70  Click
Ti 2p3/2 Bi12TiO20 457.30  Click
Ti 2p3/2 (TiS2)0.80(Co(C5H5)2)0.20 457.30  Click
Ti 2p3/2 [C9H16C5H3][C5H5]TiCl2 456.91  Click
Ti 2p3/2 [C5H5(CH3)5)C5H5]2TiCl2 456.92  Click
Ti 2p3/2 [C7H12C5H3]2TiCl2 456.74  Click
Ti 2p3/2 Ti/(-C4HS((CH2)5CH3)-)n 458.15  Click
Ti 2p3/2 Ti/(-C4HS((CH2)5CH3)-)n 455.70  Click
Ti 2p3/2 Ti0.001(Fe2O3)0.999 458.00  Click
Ti 2p3/2 [C5H5(CH3)2)C5H5]TiCl2 457.06  Click
Ti 2p3/2 [C5H5(CH3)5)]2TiCl2 456.46  Click
Ti 2p3/2 [C8H14C5H3]2TiCl2 456.70  Click
Ti 2p3/2 La0.28Pb0.71Ti1.00O3 459.00  Click
Ti 2p3/2 [C8H14C5H3][C5H5]TiCl2 457.05  Click
Ti 2p3/2 [C7H12C5H3][C5H5]TiCl2 457.08  Click
Ti 2p3/2 [C7H12C5H3][C5H5]TiCl2 457.04  Click
Ti 2p3/2 [C5H5(CH3)2)]2TiCl2 457.01  Click
Ti 2p3/2 [C5H8C5H3][C10H15]TiCl2 456.88  Click
Ti 2p3/2 [C5H8C5H3][C10H15]TiCl2 456.83  Click
Ti 2p3/2 TiN0.23 454.30  Click
Ti 2p3/2 TiN0.28 454.40  Click

 Periodic Table 


 

 

Statistical Analysis of Binding Energies in NIST XPS Database of BEs

 

 

 Periodic Table 


 

Advanced XPS Information Section

Expert Knowledge, Spectra, Features, Guidance and Cautions
for XPS Research Studies on Titanium Materials

 

 


 

Expert Knowledge Explanations

 Periodic Table 


 

Titanium Chemical Compounds

 

Peak-fits and Overlays of Chemical State Spectra

Pure Titanium:  Ti (2p)
Cu (2p3/2) BE = 932.6 eV
TiO2:  Ti (2p)
C (1s) BE = 285.0 eV
TiF4:  Ti (2p)
C (1s) BE = 285.0 eV

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 


 

Overlay of Ti (2p) Spectra shown Above

C (1s) BE = 285.0 eV

 Periodic Table 



Native Oxide on Titanium (Ti
o)
Naturally Formed in lab air at 25 Co 1 atm 

Survey Spectrum from Native Oxide on Tio
Flood gun is OFF, C (1s) BE = 286.8 eV
Ti (2p) Chemical State Spectrum from Native Oxide on Tio
Flood gun is OFF, C (1s) BE = 286.8 eV

 
O (1s) Chemical State Spectrum from Native Oxide on Tio
Flood gun is OFF, C (1s) BE = 286.8 eV
C (1s) Chemical State Spectrum from Native Oxide on Tio
Flood gun is OFF, C (1s) BE = 286.8 eV

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 


 

Titanium Di-oxide (TiO2)
Rutile, single crystal, cleaved to expose bulk

Survey Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV
Ti (2p) Chemical State Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV

   .
O (1s) Chemical State Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV
C (1s) Chemical State Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV

   .
Ti (3p) Chemical State Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV
Freshly cleaved to expose bulk
Ti (3s) Chemical State Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV
Freshly cleaved to expose bulk

 
Valence Band Spectrum from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV
Freshly cleaved to expose bulk
Auger Signals from TiO2
Flood gun is ON, C (1s) BE = 285.0 eV
Freshly cleaved to expose bulk

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 

 


 

Titanium Chemical Compounds

 

 Periodic Table 



 

Quantitation Details and Information

Quantitation by XPS is often incorrectly done, in many laboratories, by integrating only the main peak, ignoring the Electron Loss peak, and the satellites that appear as much as 30 eV above the main peak.  By ignoring the electron loss peak and the satellites, the accuracy of the atom% quantitation is in error.

When using theoretically calculated Scofield cross-section values, the data must be corrected for the transmission function effect, use the calculated TPP-2M IMFP values, the pass energy effect on the transmission function, and the peak area used for calculation must include the electron loss peak area, shake-up peak area, multiplet-splitting peak area, and satellites that occur within 30 eV of the main peak.

 Periodic Table 


 

Flood Gun Effect on Native Oxide of Titanium

 

Native Oxide of Titanium Sheet – Sample GROUNDED
versus
Native Oxide of Titanium Sheet – Sample FLOATING

 


 

Native Oxide of Titanium Sheet – Sample Grounded

Electron Flood Gun:  0 Voltage (FG OFF), Min Voltage versus Max Voltage

Ti (2p) O (1s) C (1s)
 Periodic Table 

 

Native Oxide of Titanium Sheet – Sample Floating

Electron Flood Gun:  0 Voltage (FG OFF), Min Voltage versus Max Voltage

Ti (2p) O (1s) C (1s)
 Periodic Table 

 Peri

 


 

XPS Study of UHV Gas Captured by Freshly Ion Etched Titanium
Reveals Chemical Shifts and Chemical States that Develop from Highly Reactive Pure Tio

Surface was strongly Ar+ ion etched to remove all contaminants, and
then allowed to react overnight with the UHV Gases – CO, H2, H2O, O2 & CH4
that normally reside inside on the walls of the chamber, on the sample stage,
and on the nearby un-etched surface a total of 10-14 hours.  UHV pump was a Cryopump.
Initial spectra are at the front.  Final spectra are at the rear. Flood gun is OFF.
Ti (2p) Signal
 O (1s) Signal C (1s) Signal
Copyright ©:  The XPS Library


 

AES Chemical State Spectra
from UHV Gas Captured Overnight by Freshly Ion Etched Titanium

Titanium ribbon was ion etched and allowed to react with residual UHV gases overnight – ~14 hr run.

Ti (LMM) Signal:
Ti at front -> TiOx at rear 
Ti KE = 413.9eV,    TiO2 KE = 408.5 eV
O (KLL) Signal:
Ti at front -> TiOx at rear
O KE = 507.3 eV

   

 

Chemical State Spectra
from TiO2 using Charge Control by AES

 
Ti (KLL) Signal:
TiO2 w charge control – JEOL Hemi-sphere (HSA) – 25 kV
High Energy Resolution Mode for Chemical States
O (KLL) Signal:
TiO2 w charge control – JEOL Hemi-sphere (HSA) – 25 kV
High Energy Resolution Mode for Chemical States

Features Observed

  • xx
  • xx
  • xx

 Periodic Table 


Titanium Alloys

   
XxCu XxCu
 Periodic Table   
XxCu XxCu

 

Copyright ©:  The XPS Library 

 



 

 

XPS Facts, Guidance & Information

 Periodic Table 

    Element Titanium (Ti)
 
    Primary XPS peak used for Peak-fitting : Ti (2p)  
    Spin-Orbit (S-O) splitting for Primary Peak: Spin-Orbit splitting for “p” orbital, ΔBE = 6.18 eV
 
    Binding Energy (BE) of Primary XPS Signal: 453.9 eV
 
    Scofield Cross-Section (σ) Value: Ti (2p3/2) = 5.22     Ti (2p1/2) = 2.69
 
    Conductivity: Ti resistivity =  
Native Oxide suffers Differential Charing
 
    Range of Ti (2p) Chemical State BEs: 454-462 eV range   (Tio to TiF4)  
Signals from other elements that overlap
Ti (2p) Primary Peak:
  xx (xx)
Bulk Plasmons:   ~xx eV above peak max for pure
Shake-up Peaks: ??
Multiplet Splitting Peaks:   ??

 

 

General Information about
XXX Compounds:
  xx  
Cautions – Chemical Poison Warning

xx 

Copyright ©:  The XPS Library 

 Periodic Table 



 

Information Useful for Peak-fitting Ti (2p)

  • FWHM (eV) of Ti (2p3/2) from Pure Tio ~0.7 eV using 50 eV Pass Energy after ion etching:
  • FWHM (eV) of Ti (2p3/2) from TiO2 xtal:  ~1.0 eV using 50 eV Pass Energy  (before ion etching)
  • Binding Energy (BE) of Primary Signal used for Measuring Chemical State Spectra:  454 eV for Ti (2p) with +/- 0.2 uncertainty
  • List of XPS Peaks that can Overlap Peak-fit results for Ti (2p):  xxxx

 Periodic Table 


 

General Guidelines for Peak-fitting XPS Signals

  • Typical Energy Resolution for Pass Energy (PE) setting used to measure Chemical State Spectra on Various XPS Instruments
    • Ag (3d5/2) FWHM (eV) = ~0.95 eV for PE 50 on Thermo K-Alpha
    • Ag (3d5/2) FWHM (eV) = ~1.00 eV for PE 80 on Kratos Nova
    • Ag (3d5/2) FWHM (eV) = ~0.95 eV for PE 45 on PHI VersaProbe
  • FWHM (eV) of Pure Elements: Ranges from 0.4 to 1.0 eV across the periodic table
  • FWHM of Chemical State Peaks in any Chemical Compound:  Ranges from 1.1 to 1.6 eV  (in rare cases FWHM can be 1.8 to 2.0 eV)
  • FWHM of Pure Element versus FWHM of Oxide:  Pure element FWHM << Oxide FWHM  (e.g. 0.8 vs 1.5 eV, roughly 2x)
  • If FWHM Greater than 1.6 eV:  When a peak FWHM is larger than 1.6 eV, it is best to add another peak to the peak-fit envelop.
  • BE (eV) Difference in Chemical States: The difference in chemical state BEs is typically 1.0-1.3 eV apart.  In rare cases, <0.8 eV.
  • Number of Peaks to Use:  Use minimum. Do not use peaks with FWHM < 1.0 eV unless it is a or a conductive compound.
  • Typical Peak-Shape:  80% G: 20% L,   or Voigt : 1.4 eV Gaussian and 0.5 eV Lorentzian
  • Spin-Orbit Splitting of Two Peaks (due to Coupling):  The ratio of the two (2) peak areas must be constrained.
  • Constraints on Peak-fitting: ??

Notes:

  • Other Oxidation States can appear as small peaks when peak-fitting
  • Pure element signals normally have asymmetric tails that should be included in the peak-fit.
  • Gaseous state materials often display asymmetric tails due to vibrational broadening.
  • Peak-fits of C (1s) in polymers include an asymmetric tail when the energy resolution is very high.
  • Binding energy shifts of some compounds are negative due to unusual electron polarization.

 Periodic Table 


 

Contaminants Specific to Titanium

  • Titanium develops a thick native oxide due to the reactive nature of clean Titanium.
  • The native oxide of Ti Ox is 4-5 nm thick.
  • Titanium forms a low level of carbide when the surface is ion etched inside the analysis chamber

 

Commonplace Contaminants

  • Carbon and Oxygen are common contaminants that appear on nearly all surfaces. The amount of Carbon usually depends on handling.
  • Carbon is usually the major contaminant.  The amount of carbon ranges from 5-50 atom%.
  • Carbon contamination is attributed to air-borne organic gases that become trapped by the surface, oils transferred to the surface from packaging containers, static electricity, or handling of the product in the production environment.
  • Carbon contamination is normally a mixture of different chemical states of carbon (hydrocarbon, alcohol or ether, and ester or acid).
  • Hydrocarbon is the dominant form of carbon contamination. It is normally 2-4x larger than the other chemical states of carbon.
  • Carbonate peaks, if they appear, normally appear ~4.5 eV above the hydrocarbon C (1s) peak max BE.
  • Low levels of carbonate is common on many s that readily oxidize in the air.
  • High levels of carbonate appear on reactive oxides and various hydroxides.  This is due to reaction between the oxide and CO2 in the air.
  • Hydroxide contamination peak is due to the reaction with residual water in the lab air or the vacuum.
  • The O (1s) BE of the hydroxide (water) contamination normally appears 0.5 to 1.0 eV above the oxide peak
  • Sodium (Na), Potassium (K), Sulfur (S) and Chlorine (Cl) are common trace to low level contaminants
  • To find low level contaminants it is very useful to vertically expand the 0-600 eV region of the survey spectrum by 5-10X
  • A tiny peak that has 3 or more adjacent data-points above the average noise of the background is considerate to be a real peak
  • Carbides can appear after ion etching various reactive s.  Carbides form due to the residual CO and CH4 in the vacuum.
  • Ion etching can produce low oxidation states of the material being analyzed.  These are newly formed contaminants.
  • Ion etching polymers by using standard Ar+ ion guns will destroy the polymer, converting it into a graphitic type of carbon

 Periodic Table 


 

Data Collection Guidance

  • Chemical state differentiation can be difficult
  • Collect principal Ti (2p) peak
  • Long time exposures (high dose) to X-rays can degrade various polymers, catalysts, high oxidation state compounds
  • During XPS analysis, water or solvents can be lost due to high vacuum or irradiation with X-rays or Electron flood gun
  • Auger signals can sometimes be used to discern chemical state shifts when XPS shifts are very small

 Periodic Table 


 

Data Collection Settings for Titanium (Ti)

  • Conductivity:  Titanium readily develops a native oxide that is sensitive to Flood Gun – Differential Charging Possible – float sample recommended
  • Primary Peak (XPS Signal) used to measure Chemical State Spectra:  Ti (2p) at 454 eV
  • Recommended Pass Energy for Measuring Chemical State Spectrum:  40-50 eV    (Produces Ag (3d5/2) FWHM ~0.7 eV)
  • Recommended # of Scans for Measuring Chemical State Spectrum:  4-5 scans normally   (Use 10-25 scans to improve S/N)
  • Dwell Time:  50 msec/point
  • Step Size:  0.1 eV/point   (0.1 eV/step or 0.1 eV/channel)
  • Standard BE Range for Measuring Chemical State Spectrum:  440-480 eV
  • Recommended Extended BE Range for Measuring Chemical State Spectrum:  440-540 eV
  • Recommended BE Range for Survey Spectrum:  -10 to 1,100 eV   (above 1,100 eV there are no useful XPS signals, except for Ge and Ga)
  • Typical Time for Survey Spectrum:  3-5 minutes for newer instruments, 5-10 minutes for older instruments
  • Typical Time for a single Chemical State Spectrum with high S/N:  5-10 minutes for newer instruments, 10-15 minutes for older instruments 

 Periodic Table 


 

Effects of Argon Ion Etching

  • Carbides appear after ion etching Ti and various reactive s.  Carbides form due to the residual CO and CH4 in the vacuum.
  • Ion etching can produce low oxidation states of the material being analyzed.  These are newly formed contaminants.
  • Ion etching polymers by using standard Ar+ ion guns will destroy the polymer, converting it into a graphitic type of carbon

 Periodic Table 

Copyright ©:  The XPS Library 


Gas Phase XPS or UPS Spectra


 

Chemical State Spectra from Literature

from Thermo-Scientific Website
  • Ti metal gives asymmetric Ti2p peaks shapes o TiO2 has symmetric peaks shapes and TiN has a complex peak shape, involving satellite features.
  • Ti2p peak has significantly split spin-orbit components (Δmetal=6.1eV).
    • Splitting -value varies with chemical state (Δnitride=6.0eV, Δoxide=5.7eV).
    • Typically FWHM for each spin-orbit component is the same, but for Ti2p the Ti2p1/2 component is much broader than the Ti2p3/2 peak. Consequently, Ti2p1/2 peak is much shorter than expected.
    • Caused by Coster-Kronig effect. (Post-ionization, Ti2p1/2 state is very short lived compared to Ti2p3/2 state.)
    • Causes difficulty in accurately peak fitting Ti2p region with multiple chemical states.



End of File