Fourier transform infra-red spectrometer IFS-113v
Well known, all solids, liquids and gases have ability to absorb electromagnetic waves in the infrared region of the spectrum. Changing the dipole moment under the action of oscillations of light waves leads to resonant absorption of incident radiation in the broad spectral range - from 5000 cm-1 to 10 cm-1.
Fourier spectrometers have several advantages comparing to conventional diffraction spectrometers. High spectral resolution, speed, aperture optical method makes FTIR spectroscopy a highly informative express method of physical and chemical analysis.
Analysis of materials and micro-structures
The stoichiometry of the composition, chemical bonding, density and porosity of the material influence the spectral position and shape of the characteristic absorption bands. For example, the characteristics of the absorption bands of 3650 cm-1 and 3400 cm-1 associated with the hydrogen bonds of hydroxyl groups and adsorbed water, based on the number of hydroxyl groups on the surface of the film and the porosity of the oxide. Thickness of the oxide film on the silicon surface is measured at the interference fringes observed in the absorption spectra. Properties other impurities that may exist in SiO2 as determined from the absorption characteristics of the respective bands.
Several examples of using infrared spectroscopy for the study of materials and microelectronic structures:
- Dielectric semiconductor substrates used in studying the properties microelectronics and transparent in the infrared region of the spectrum.
- The optical properties of titanium nitride and silicon dioxide layers obtained by different technological means.
- Measurements of the oxygen or carbon impurities in silicon substrates. Researching of the bound states and precipitates of nitrogen, hydrogen, fluorine in silicon and polysilicon.
- Epitaxial layers on semiconductor surfaces thickness measurement.
- Borosilicate, phosphosilicate glass and suicides.
- Hydrogenated amorphous silicon, silicon-germanium, silicon-carbon bonds. Porous silicon, diamond film, boron nitride.
- Polyimide film, SOI, SIMOX, and other materials and the structure of micro-and nanotechnology.
