Anasys Instruments

Fig. 2.27 SEM images of different specialized AFM probes (1) tips of widely different radii (a) 870 nm, (b) 150 nm and (c) 20 nm (d, e) thermal probe and tip (images courtesy Anasys Instrument Inc.)...

Other uses of an IR microscope in forensic analysis include the examination of fibers, drugs, and traces of explosives. For example, oxidation of hair can occur chemically or by sunlight oxidation of cystine to cysteic acid can be seen in hair fibers by FTIR microscopy (Robotham and Izzia). Excellent examples in full color of FTIR imaging microscopy can be found on the websites of companies like PerkinElmer and Thermo Fisher Scientific. Our limitations in use of gray scale make many of the examples unsuited for reproduction in the text. A novel IR microscope combined with atomic force microscopy, the nanoIR platform from Anasys Instruments (www.anasysinstruments.com), permits nanoscale IR spectroscopy, AFM topography, nanoscale thermal analysis, and mechanical testing. 

Figure 7.4. Micromachined silicon nanoprobe (a) the cantilever (b) the tip, which has the same sharpness as a conventional AFM probe (reproduced with permission of Anasys Instruments Inc.).

Figure 7.15. Melting (a) of PET with different applied probe forces. Note that force is proportional to probe deflection. Glass transition (b) of PMMA with different applied probe forces. The melting temperature is not influenced by changes in applied force, but the glass transition temperature shows a significant decrease as the applied force is increased, as expected, (reproduced with permission of Anasys Instruments Inc.).

At the time of writing there is only one manufacturer of micro/nano-TA equipment Anasys Instruments, (www.anasysinstruments.com). They supply the hardware and software for local thermal analysis and thermal imaging that can be interfaced with the most popular types of atomic force microscope. More recently they have launched an instrument based on an optical microscope, the Vesta system, which is simpler to use than an atomic force microscope but the spatial resolution is limited to approximately 1.5 micrometers, see Fig. 7.22. The Wollaston probes are supplied by Veeco (www.veeco.com) and are, therefore, compatible only with Veeco AFMs. The nanoprobes are supplied by Anasys Instruments and can be used with most popular makes of AFM. In addition, Anasys Instruments supply calibration kits containing temperature standards. More recently they have launched an instrument based on an optical microscope, the Vesta system, which is simpler to use than an atomic force microscope, but the spatial resolution is limited to approximately 1.5 pm. 

Figure 7.22. Vesta system for micro-thermal analysis. Courtesy of Anasys Instruments.

The Anasys instrument has been described in several publications [37-41] of which the review paper by Dazzi et al. [41] is the most detailed. The spectra measured with this instrument are essentially identical to those measured on a macrosample of the same material unless, of course, the polymer has microdomains of differing structure either because of immiscibility of two or more copolymers or because of the effect of orientation. The spatial resolution is significantly better than 100 nm, as reported by Dazzi et al. who embedded a 3 pm diameter PS bead in epoxy and demonstrated the very rapid change in spectrum on the edge of the PS bead [41]. 

Figure 12.25 Optical configuration of Anasys instrument where the sample is illuminated from above and the need for a thin sample deposited on an IRE is eliminated.

Figure 6.7. Resistively heated AFM probes used for thermal imaging and thermal analysis. (A) Wollaston wire probes used in the commercial microTA system. (B) Microfabricated silicon probes with integral heaters at the base of the tip used in the commercial nanoTA. (Figure 6.7A from Anasys Instruments [134] reproduced with permission. Figure 6.7B from Hammiche and Pollack [157] unpublished.)...

Anasys Instruments nano-TA Probes. Available at http //www.ana,sysinstruments.com/ probes.php fi=products. Accessed December 2006. 

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