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Category
- Spectroscopy and Spectrometry » X-Ray Photoelectron Spectroscopy
Booking Details
Angle resolved XPS
Depth profile XPS
Facility Management Team and Location
Facility Features, Working Principle and Specifications
Facility Description
Electron spectroscopy for chemical analysis instrument is used for characterisation of surfaces and interfaces. It can provide great deal of information such as elemental composition, chemical state composition of elements present, spatial distribution of elements and their chemical state, composition as a function of depth, Central Surface Analytical Facility thickness of thin films etc.
Electron spectroscopy for chemical analysis (ESCA) instrument comprises of X-ray photoelectron
spectroscopy (XPS). The surface to be analyzed is placed in a vacuum environment and then irradiated with photons (X-ray or
Ultra-violet). The incident photons release electrons (called photoelectrons) from their electronic structure
(core-levels and valence band) and ionize the atoms. The kinetic energy and the number of
photoelectrons are precisely measured and counted respectively using an analyzer-detector based on
which the binding energy and the intensity of the photoelectron are determined.
Limitations: ESCA can detect all the elements except H and He. The detection limit is 0.1%
Reference Books:
1. An Introduction to Surface Analysis by XPS & AES, John F. Watts & John Wolstenholme, Wiley
2003.
2. Surface Analysis – The Principle Techniques, Edited by John Vickerman & Ian Gilmore, Wiley
2009.
- Two chamber ultra high vacuum system: Analysis chamber (< 2.0 x 10-9 Torr) and Sample load-lock chamber (< 5.0 x 10-8 Torr).
- Automated sample transfer mechanism and five-axis sample manipulator.
- XPS Source : Monochromatic (AlK alpha) x-ray source: 1486.6 ev ; (Ag L alpha) x-ray source: 2984.3 ev
- Angle resolved XPS
- Electron energy analyser and detector: Concentric hemispherical analyzer (CHA) for spectroscopy, and Spherical mirror analyzer for parallel imaging. Multichannel plates stack with delay-line detector for counting. Spectroscopy, snapshot and imaging modes with option of large area and small area analysis.
- Differentially pumped ion gun: High performance gun for precision depth profiling, Energy range 500 eV to 4 keV for sample etching (cleaning) and depth profiling.
- Charge neutralizer: For non-conducting samples
- Software system: Windows based software (ESCApe) for automated sample transfer, data acquisition and data processing. Site license for data processing.
- Capabilities: Under ideal sample preparation conditions the following can be achieved
XPS: energy resolution is ~0.5 eV, & 0.7 eV in case of non-conducting samples
Instructions for Registration, Sample Preparation, User Instructions and Precautionary Measures
Internal users can register online. The samples should be submitted personally on the day of allotted time slot.
External users need to Get register at below link
https://www.istem.gov.in/register
Apply at below link
https://www.istem.gov.in/equipment-info/45746/Central-surface-analytical-facility-ESCA-Facillity.
samples can be send through post, in transportation , if sample damages, we will not be responsible.
down load registration form and submit it to lab along with the authority letter, online payment details.
Analysis will be performed on the next day and results will be sent through email.
2) Getting Back the samples: Users desiring to get back the samples need to mark on the form.
Collect them from the lab between 9:30 AM to 11:00 AM after two-three days of completion of the
work (intimated through mail) and uncollected samples will be disposed-off after ten days of
intimation of the completion of the work and no reminders will be sent.
Maximum size of samples should be (10 x 10 x 5) mm. Smaller samples of the size 3 mm x 3 mm or 3 mm diameter are more suitable. Bigger or smaller samples than the size mentioned here may be possible and user is required to check with lab staff.
1) Label the samples only on the containers. Sample labels/codes should be brief (less than three letters/numbers) or may use just single digits (1,2,3..)
2) Keep the samples clean. Try not to touch the surface of your sample with anything (fingers, gloves, breath etc.)
3)The sample should be completely dry and it should be stable in ultra high vacuum (no out-gassing allowed).
3) Powders should be made into pellet or form a thin coating on a clean conducting substrate like silicon, aluminum or copper foil. Pressing powder in to indium foil is also another method.User should clearly mention if the sample needs etching (surface cleaning) before recording the data. It may be noted that the etching may alter the chemical composition and chemical state to some extent.
4) Samples containing organic molecules /polymers and some high vapour pressure elements such as Na, K, S, P, Zn, Se, As, I, Te or Hg are not suitable for depth profile analysis.
Charges for Analytical Services in Different Categories
Analysis mode | Charges per sample or per hour (as applicable) |
| |||
IIT-B academic | IIT-B consultancy | Non-IITB Academic | National R&D centers | Industry/Non-govt agency | |
XPS | 500 | 1500 | 4500 | 5000 | 10000 |
XPS + depth profiling or imaging | 1500 | 4500 | 12500 | 15000 | 20000 |
Specialized in-situ XPS measurement (per hour of instrument usage)* | 5000 | 10000 | 15000 | 20000 | 25000
|
For external users
*GST extra as on 1.8.2017:
If the recipient of the report is from Maharashtra: 9% SGST and 9% CGST
If the recipient of the report is from outside Maharashtra: 18% IGST