Central Facilities

Surface Characterization Lab

Location: ACMS 110

Instrument: X-ray Photoelectron Spectroscopy(XPS) with Auger Electron Spectroscopy(AES) Module
Model/Supplier:PHI 5000 Versa Prob II,FEI Inc.

The "Surface Characterisation Lab" of ACMS houses a "X-ray Photo-Electron Spectroscopy (XPS) with Auger Electron Spectroscopy (AES) module and C60 sputter gun". This facility is available for usage by all the members of the Institute research community and also, it can be availed for usage for research purposes by Educational Institutions, National labs/ Private labs and Industries. However, there are certain set of "Rules and Regulations" laid out to get the best utilisation/ operation/ management of the facility and also, in the interest safety of machine as well as the operators/users. It is request that all users co-operate with appreciating the spirit of these "Rules and Regulation" and kindly comply with. The operation and maintenance of the facility is guided by a "Co-ordination Committee" formally formed by HOD of ACMS and approved by the Institute Authorities. All suggestions and complaints may be registered through any one of the user committee member. The "Usage Charges" is collected towards partial recovery of "cost of maintenance and repairs" and these receipts will be handled as per the Institutes existing norms. Time on the system can be availed by the specified procedures for the same. There are some sample requirements for analysis and certain material will not be accepted for analysis in our facility as mentioned in "Sample Restrictions and Requirement". It is mandatory on all users, both from within Institute and Outside Institute, to submit a declaration on materials being provided to the facility for analysis in the system before availing the facility. Our Instrument and its Capabilities XPS with AES Module with Ar ion as well as C60 sputter Guns Model/Supplier: PHI 5000 Versa Probe II, FEI Inc. XPS is a spectroscopic technique to quantitatively measure the elemental compositions and chemical and electronic states of the elements of a material, including their bond energy. To obtain the XPS spectra, the sample is irradiated with a beam of X-rays. The kinetic energy and number of electrons escaping from the top 1 to 7.5 nm of the material are measured and analyzed. The VersaProbe can be used much like an SEM when characterizing non-homogeneous materials. The VersaProbe provides high sensitivity for micro area spectroscopy with x-ray spot sizes from < 10 μm to 200 μm. This is a direct result of using a focused x-ray beam and a spectrometer that is optimized for high sensitivity. This design allows complete XPS experiments to be performed at all spot sizes including: survey spectra, multiregion high resolution spectra, sputter depth profiling, angle dependent depth profiling, line scans, and maps. Operating in a mode analogous to a rotating anode, a high power (100 W) 100 μm diameter x-ray beam is scanned 1.4 mm in the non-dispersive direction of the x- ray monochromator at high speed, providing a large rectangular analysis area with both high sensitivity and high energy resolution. The width of the rectangular area is user adjustable from 0.1 to 0.5 mm. VersaProbe chemical state maps are created by scanning the x-ray beam pixel by pixel over the defined area. The dimensions of the mapped area, pixel density, and spot size are user adjustable. The ultimate spatial resolution for spectroscopy and mapping is the same, less than 10 μm. The high micro area sensitivity of the VersaProbe makes depth profiling with small diameter x-ray beams very practical. An additional benefit of the microprobe design is that when the analysis area is small, the size of the sputter crater required to provide optimum depth resolution is reduced. Reducing the size of the sputter crater increases sputter etch rates which will reduce experiment time and make it practical to characterize thicker films. The optional C60 sputter ion gun provides the ability to sputter clean polymer surfaces without causing significant chemical damage. For a number materials it is also possible perform thin film analysis with significantly less chemical damage than would be expected when using an inert gas ion beam such as argon. The additional electron gun provides a raster scanned electron beam for AES spectroscopy, depth profiling, and mapping.

About Application

XPS is routinely used to analyze a wide variety of materials (both conducting and non-conducting) including inorganic compounds in powder form, metal alloys, semi- conductors, polymers, glasses, ceramics, paints, viscous oils, glues, papers, inks, woods, bones, medical implants and several other biomaterials. The surface characterization of range of materials include metals, polymers, and coatings can be performed through this technique. The unique features of XPS is that it can detect all elements with an atomic number (Z) of 3 (lithium) and above, within 0.01 monolayers of the element on a surface. The ultimate spatial resolution for spectroscopy and mapping is the same, less than 10 μm. The high micro area sensitivity of the VersaProbe makes depth profiling with small diameter x-ray beams very practical.

Access to the Facility

Only "Approved users" and "Approved samples/materials" will be entertained by facility. The access for usage is through a formal approval from the "Facility Adminstrators". Institute users will be granted approval to use the facility after providing valid account numbers with DORD/Institute for charges recovery in the "Request for Usage Approval". Advance payment is not expected but, it will be periodically recovered. However, Institute users can deposit advance payments from which the charges will be deducted and accounts settled.

We encourage researchers from outside IITK use our facility. Efforts will be made to provide 20-25% Instrument time to outside IITK users. For "Outside IITK Users" advance payment is expected for getting time slots booked. The charges is to be paid only as Demand drafts drawn in favour of:

"The Registrar, Indian Institute of Technology, Kanpur".
In the case of direct money transfer, all details of the transfer needs to be provided to the facility administrator. Acknowledgement of the money received will be provided by the facility and original receipt from the IITK will be sent as and when received from the IITK authorities.

Members of Facility Co-ordination Committee

1. Dr. T.G. Gopakumar, Chemistry, (Convener) (gopan@iitk.ac.in)
2. Prof. Nishith Verma, Chemical Engineering (nishith@iitk.ac.in)
3. Dr. Sri Sivakumar, Chemical Engineering (srisiva@iitk.ac.in)
4. Dr. Sarang Ingole, Materials Science and Engineering (sarang@iitk.ac.in)

CONTACT

Instrument: Optical Profilometer
Model/Supplier: Bruker Contour GT-K