_Applications by measurement type |
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| Film Thickness & Refractive Index |
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For the characterization of films, several parameters (film thickness, refractive index, coefficient of thermal expansion, glass transition temperature etc.) are necessary depending on the particular application. Film thickness however, is a parameter of interest that does not depend on the applications, and is needed in all cases. FR-tools are capable to measure the film thickness of various films, supported or suspended, thin or thick, single films or stack of films etc. Actually the limitations of FR-tools in film thickness measurement are very small and in certain cases could be overcome. For example when a very thin transparent layer should be measured, all the optical components to be used i.e. light source, optical fibers and spectrometer should be tuned to the smaller wavelength range possible. In other cases i.e. samples with very high surface or interface roughness, might be impossible to measure the film thickness. |
| The procedure to measure and calculate the film/films thicknes of the single/multy layer stack involve the acquisition of the reflectance spectrum, as described in Technology/Reflectance section and illustated in fig.1. More detail presentation of the procedure you can find in FR-Monitor manual, in Download section. The physics behind and the algorythms for the calcualtion of the thickness of a k-film layer sample were presented in White Light Reflectance Spectroscopy (WLRS) section. For the film thickness calculation two spectra are needed a) the reflectance spectrum in one of the following modes: reflectance, scope, corrected scope and b) the reference spectrum (please also refer to Technology/Basic OpticalSpectra section). With FR-Monitor the film thickness of more than one layer can be calculated if necessary. The accuracy of film thickness measurement depends on various parameters related either to the optical properties of the films present but also on the spectrometer characteristics. |
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| Bellow you can find varius reprensetative examples of film thickness calculations, as they perfomed with FR-Tools and FR-Monitor. |
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| Measurement of a single SiO2 film over Si substrate, with 564.6nm thickness. The measurement was performed in 300nm - 600 wavelength range. |
Measurement of a double layer stack of SiO2/Si3N4 over Si substrate, with 573nm and 141.8nm thickness respectively. The measurement was performed in 300nm- 70nm wavelength range. |
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| Measurement of a very thin SiO2 film over Si substrate, with 5.73nm thickness. The mesurement was performed in 210nm - 360nm wavelength range. |
Measurement of a very thin SiO2 film over Si substrate, with 12.09nm thickness. The measurement was performed in 210nm - 360nm wavelength range. |
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| Measurement of a very thin Au film over Si substrate, with 7.63nm thickness. The measurement was performed in 320nm - 500nm wavelengt range. |
Measurement of a very thin Au film over Si substrate, with 15.03nm thickness. The measurement was performed in 320nm - 500nm wavelength range. |
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| Measurement of a double layer stack of SiO2/PHEMA over Si substrate, with 995.5nm and 725.5nm thickness respectively. The measurement was performed in 540nm- 780nm wavelength range. |
Measurement of a very thick SU8 polymer film over Si substrate, with 95.12μm thickness. The measurement was performed in 860nm - 900nm wavelength range. |
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| Measurement of a double layer stack of SiO2/Si over Si substrate, with 481.8nm and 5.042μm thickness respectively. The measurement was performed in 930nm- 1190nm wavelength range. |
Measurement of a suspended Si membrane with 4.999μm thickness. The measurement was performed in 930nm - 1190nm wavelength range. |
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