• Pulsed Laser Deposition

  • Confocal Raman Microscopy

  • PLS

  • X-ray photoelectron spectrometer

X-ray photoelectron spectrometer: (SPECS, Germany)

X-ray photoelectron spectroscopy (XPS) is also called electron spectroscopy for chemical analysis (ESCA) and is surface sensitive and quantitative technique (Fig. 1). It is used to understand the chemical composition of the material, empirical formula and electronic state of the element in the material. A typical XPS spectrum (Fig. 2) is graph between the kinetic energy or binding energy of electron versus intensity of electrons.


Fig.1 XPS instrument.


Fig.2 XPS spectrum of ZnO.

The above spectrum shows a typical XPS survey scan spectrum of a ZnO thin film. From the graph, by observing the position of the peak one can determine the oxidation state of the corresponding element.
Typical time to measure one sample (including vacuum) is 10hr/sample.

Photoluminescence Spectroscopy
HORIBA JOBIN YVON (FluoroLog-3Spectrofluorometer)
Instrument specification:
                              Excitation wavelength Range: 250 to 800 nm
                              Emission wavelength can measure: 270 to 1700 nm
                              Wavelength Accuracy: 0.5 nm
                              Light Source: Xenon Lamp
  • A Xenon lamp source
  • 2 detectors for visible and NIR measurements
  • Sample compartment (sample holder for liquid and solid samples)

Flurolog-3 is very sensitivespectroflurometer, which can measurewavelength from 270 -1600 nm. The Double grating monochromators provide superior stray light rejection for highly scattering samples. The measurements can be done at accuracy of 0.5 nm steps and a scanning speed of 150 nm/sec or more. We encourage the user to bring pellets for solid samples and properly centrifuged liquid samples for proper measurement. TAs are not responsible for the sample contamination or damage during the measurement.


Diffuse Reflectance Spectroscopy

Diffuse reflectance is an excellent sampling tool for powdered or crystalline materials in the midIR and NIR spectral ranges. It can also be used for analysis of intractable solid samples. As with transmission analysis, samples to be run by diffuse reflectance are generally ground and mixed with an IR transparent salt such as potassium bromide (KBr) prior to sampling. Diffuse reflectance is an excellent sampling technique as it eliminates the time-consuming process of pressing pellets for transmission measurements. Diffuse reflectance can also be used to study the effects of temperature and catalysis by configuring the accessory with a heating chamber.

Deuterium Tungsten Halogen Light Source

The DH-2000-BAL Deuterium Tungsten Halogen Light Source combines the continuous spectrum of deuterium and tungsten halogen light sources in a single optical path, producing a powerful, stable output from 215-2000 nm.

The DH-2000-BAL Deuterium Tungsten Halogen Light Source combines the continuous spectrum of deuterium and tungsten halogen light sources in a single optical path, producing a powerful, stable output from 215-2000 nm.

  1. Eliminates D-alpha line in deuterium source
  2. Stable output 215-2000 nm
  3. Innovative filtering technology produces smooth spectrum across entire range
D-alpha Line

All deuterium-tungsten halogen sources have a D-alpha line, revealed as a jagged peak in the visible portion of the spectrum, that produces "unbalanced" output in the deuterium and tungsten halogen sources. Correcting for this deuterium line -- a sharp spectral feature near 655 nm -- is difficult. For example, if you adjust spectrometer integration time to reduce the intensity of this saturated spectral line, the efficiency of the system at UV wavelengths drops significantly, compromising signal-to-noise performance. Also, spectrometer efficiency is greatest in the same general spectral range as the 655 nm line, exaggerating its effects.

Proprietary Filtering Technology

Using the same high-precision patterned dichroic filter technology that distinguishes our Linear Variable Filters, the DH-2000-BAL balances the intensity of the deuterium and tungsten halogen sources, producing a "smoother" spectrum across the entire wavelength range and eliminating problems associated with saturation. By comparison, most combination UV-NIR sources can be adjusted for relative intensity only.

DH-2000-BAL Specifications
Dimensions 150 mm x 135 mm x 319 mm
Power consumption 25 W (deuterium); 20 W (tungsten halogen)
Weight 3.8 kg
Wavelength range 215-400 nm (deuterium bulb) 360-2000 nm (tungsten halogen bulb)
Humidity 5-95% without condensation at 40 °C
Tungsten bulb voltage adjustable from 4.5 to 11.5 volts
Lamp current Operating 85 V/0.3A
Lamp lifetime 1,000 hours
Lamp voltage Ignition 350 V/20°
Current voltage drift <0.01% per hour
Current voltage stability <5 x 10-6 peak-to-peak (0.1-10.0 Hz)
Operating temperature 5 °C - 35 °C
Power requirements 85-264 V 50/60 Hz
Total power 100 W
Power consumption 190 W maximum
Warm-up time 40 minutes (deuterium); 20 minutes (tungsten halogen)

Confocal Raman Microscopy

X-ray photoelectron spectrometer: (SPECS, Germany)
About the Instrument:

The alpha300 R is an advanced Raman imaging systems. It provides fast imaging, high spectral sensitivity and spatial resolution embedded with excellent analysis software. This system offers the unique ability to acquire chemical information non-destructively with a resolution down to the optical diffraction limit (~200 nm). A highly efficient combination of filters, optical components and sensitive detectors available are the key to the extremely short integration times of the various imaging modes. In typical experiments, the acquisition time for a single Raman spectrum is significantly less than 100 milliseconds. The confocal setup reduces unwanted background signals, enhances contrast and provides depth information.

Excitation Lasers:
The system currently has one laser source [Nd:YAG, maximum output power is 40 mW at 532 nm]. Laser light going both from the laser to the microscope and from the microscope to the spectrometer is fiber coupled.
Scan Stage:
The alpha300 uses piezoelectrically driven 3-axis flexure stage to scan the sample for all modes of operation.The flexure provide ultra high resolution and exceptional guiding precision. The maximum scan range is 100 x 100 μm2 and 20 μm in Z-direction.
The alpha300 system equipped with Hamamatsu H8259 series photon counting photomultiplier tube (PMT), high voltage circuit and Peltier cooled charge coupled device (CCD) were used for high sensitive detection (range from 400-800nm) of photons.
Available Objectives:
  • 10x/0.25
  • 20x/ 0.4, /0.17, WD 3.9mm
  • 60x/ (oil immersion)1.0, /0, WD 2.8mm
  • 100x/ 0.90, /0, WD 0.26mm
Raman Mapping
Table 1 Raman imaging on the cross sectioned diamond coated WC-Co tool variants
To understand the carbon, boron distribution and its uniformity in the interfacial region, Raman mapping was done on the diamond coated cross-sectional samples using Nd-YAG laser with 532 nm excitation wavelength.
Table 1 (a,b,c,d) shows the average integrated intensity variation of Raman spectrum for MCD (Microcrystalline diamond coatings), NCD (Nanocrystalline diamond coatings), BDD (Boron