Frustrated multiple internal reflection

Literature values of the contact angles for various liquids on four of the five polymers used in this work are given in Table I. These values may be compared with those for our unirradiated polymers. In the case of polystyrene, exhaustive methanol or n-heptane extraction followed by drying did not result in a change in contact angles, and residual extractant could not be observed by means of frustrated multiple internal reflectance (FMIR) spectra of the films. 

FMIR Frustrated multiple internal reflectance (spectroscopy)... 

The Infrared Internal Reflectance Approach An interesting alternative method of minimizing the solution path-length is to employ internal reflectance or attenuated total reflectance (ATR) and this was the approach adopted by the authors of the first report on the acquisition of in situ infrared spectra Mark and Pons [39] employed the ATR approach, [or, as they termed it, frustrated multiple internal reflection (MIR)-see below], to... 

ATR units were originally built for a single reflection, but were later modified for several reflections. Currently these units are available for multireflections, and are usually called FMIR (frustrated multiple internal reflection). 

ATR. Attenuated total reflectance and its extension, frustrated multiple internal reflectance (FMIR), are excellent techniques for the analysis of surfaces. In these techniques the sample does not have to be reflecting, as the reflection is done by the crystal-sample interface (Section 3.8). 

Attenuated total reflection (ATR) has grown into the most widely practiced technique in infrared spectrometry. The reasons for this are fairly straightforward the technique requires little or no sample preparation, and consistent results can be obtained with relatively little care or expertise. The technique is not foolproof, but it can be very forgiving. ATR spectrometry is known by a number of alternative names, for example, multiple internal reflection (MIR), which is not to be confused with mid-infrared, frustrated multiple internal reflection (FMIR), evanescent wave spectrometry (EWS), frustrated total internal reflection (FTIR), which is not the same as Fourier transform infrared (FT-IR) spectrometry, and internal reflection spectrometry (IRS), but IRS is better known, at least in the United States, as the Internal Revenue Service. 

ATR has been found as an easy to use, non-destmctive and surface-sensitive IR sampling technique for the in situ investigation of CMP processes (Hind et al., 2001). It was initially pushed by Harrick (1967) and comprehensively treated in his early book and following editions together with Mirabella (1985). Numerous alternative and partially deceptive names are used instead of ATR spectroscopy internal reflection spectroscopy, evanescent wave spectroscopy, frustrated total internal reflection (FTIR, which should not to be confused with Fourier-transform infrared spectroscopy) and multiple internal reflection (MIR, which should not to be confused with mid-infrared )- Therefore, in the following the term ATR as defined in Section 14.4.1 and illustrated with Figure 14.8 is used exclusively. 

The internal reflectance technique has been available in several different forms for many years (18, 19). It is also known as ATR and multiple internal reflectance or frustrated MIR (MIR/FMIR). 

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