Imaging XPS

FIGURE 12.4 Wide scan x-ray photoelectron spectroscopy (XPS) images of unaged and aged melamine fiber filaments. (From Rajeev, R.S., Bhowmick, A.K., De, S.K., Gong, B., and Bandyopadhyay, S., J. Adh. Set Technol., 16, 1957, 2002. With permission.)... 

The irradiating X-ray beam cannot be focussed upon and scanned across the specimen surface as is possible with an electron beam. Practical methods of small-spot XPS imaging rely on restriction of the source size or the analysed area. By using a focussing crystal monochromator for the X-rays, beam sizes of less than 10 pm may be achieved. This must in turn correspond with the acceptance area and alignment on the sample of the electron spectrometer, which involves the use of an electron lens of low aberration. The practically achievable spatial resolution is rarely better than 100 pm. A spatial resolution value of 200 pm might be regarded as typical, and it must also be remembered that areas of up to several millimetres in diameter can readily be analysed. 

Artyushkova K, Fulghum JE (2002) Multivariate image analysis methods applied to XPS imaging data sets. Surface Interface Anal 33 185... 

XPS Imaging Selective Adsorption of HPAM in Mineral Mixtures... 

Fig. 11 Laterally gold structured silicon wafer to control the spatial adsorption of PVFA-co-PVAm (a) photograph of the gold structured silicon wafer (genuine size of the gold islands 45 pm by 45 pm), (b) spatially resolved XPS image of the lateral gold layer (the Au 4f peak is depicted in black whilst the peaks of O 1 s and Si 2p are pale), (c) spatially resolved XPS image of 11-mercaptoundecanoic acid adsorbed on the laterally structured gold layer (the S 2p peak is depicted in white whilst Si 2p is dark)...

Figure 7.21 XPS images of a TiAIN thin film on a stainless steel substrate (a) Ti 2p photoelectron image and (b) Fe 2p photoelectron image. (Reproduced with permission from D. Briggs and J.T. Grant, Surface Analysis by Auger and X-ray Photoelectron Spectroscopy, IM Publications and Surface Spectra Ltd, Chichester. 2003 IM Publications.)...

This reaction scheme was investigated by contact angle measurements and XPS. Images of water and diiodomethane droplets of the original gold substrate, of the SAM before and after UV-illumination, as well as after the post-treatment with perfluorobutyryl chloride are presented in Fig. 1. The contact angles and the calculated surface tension are summarized in Table 1. 

In tandem with the spectra, XPS imaging is important for asses ng coating coverage. This is illustrated in Fig. 3 for a region of plasma-treated polypropylene mesh where the DEGDME coating is incomplete. 

Visual inspection of the iron surface, after tribotesting at 150 °C, revealed areas with different morphologies. A wear scar showing several distinct wear tracks was detected across the contact area. In figure 6, an XPS image of Fe2p3 2 example of the distribution of... 

Figure 6. XPS image of Fe2p3/2 of an Fe-coated Ge ATR crystal after tribotesting at 150 °C in the presence of the 20 wt% ZnDTP solution in PAO. The position of the wear tracks in the acquired XPS image and the distribution of the selected points for subsequent small-area XPS analysis are shown. The dimensions 2 x 2.8mm indicate the real size of the analyzed area on the surface sample taking into account the emission angle of 45° and the consequent distortion of the image.

The XPS image was based on the intensity of the Cl 2p peak, whereas the infrared image was based on the absorption at the band at 1333 cm used for identification of PVC. The PVC enriched (bright) areas in the images were... 

XPS images recorded from the interfacial failure surfaces of an adhesively bonded aluminum joint, prepared using an organosilane primer, with an instrument of the type shown inO Fig. 9.14. The optical mirror images are complementary views of the fracture surfaces and are mirrored along the dotted line. Visually the failure appears to be interfacial with the fracture path moving from one interface to the other at the boundary between metal and adhesive interfacial failure surfaces... 

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