Ellipsometric imaging

Based on ellipsometric imaging of titania films prepared from small (-0.5nm diameter) precursors [9,10], it is likely that the elimination of porosity in the deposited film (A in Fig. 17) occurs primarily at the final stage of drying. Figures 20a and 20b show the profiles of refractive index and volume fraction solids, (j), as a function of distance from an arbitrary... 

Ellipsometric image of a 28 vol% H2O and 72 vol% n-propanol solution during dip coating at lOcm/min. A water-rich region grows near the drying front due to the preferential evaporation of propanol. From Hurd [11]. 

Locus of ellipsometric extinctions for null detection for two values of the refractive index, n, where n, < /ij- During ellipsometric imaging, motorized polarizers allow searching along paths ABCD or BE that guarantee crossing an extinction condition between the bounding indices, n and n. From Hurd and Brinker [10],... 

In the case of Langmuir monolayers, film thickness and index of refraction have not been given much attention. While several groups have measured A versus a, [143-145], calculations by Knoll and co-workers [146] call into question the ability of ellipsometry to unambiguously determine thickness and refractive index of a Langmuir monolayer. A small error in the chosen index of refraction produces a large error in thickness. A new microscopic imaging technique described in section IV-3E uses ellipsometric contrast but does not require absolute determination of thickness and refractive index. Ellipsometry is routinely used to successfully characterize thin films on solid supports as described in Sections X-7, XI-2, and XV-7. 

A newer and perhaps more useful application of ellipsometry to Langmuir films is their lateral characterization via ellipsometric microscopy [146], A simple modification of the nuU ellipsometer allows one to image features down to 10-/im resolution. Working with a fixed polarizer and analyzer, some domains are at extinction while others are not and appear bright. This approach requires no fluorescent label and can be applied to systems on reflective supports. 

Figure 3. SPM topography images (2x2 microns) of three different islandlike PS brushes prepared by grafting-to method, effective ellipsometric thickness of PS layer 7.5M).5 nm.

AFM topographic images. X-ray photoelectron spectroscopic (XPS) analysis, and ellipsometric and contact angle with water droplet (Table 3.2) measurements... 

Figure 18 Schematic view of the micropatterned Langmuir-Blodgett film with all relevant dimensions Ellipsometric microscopy images of the sample. The angle of incidence was ip = 55.8°. The gray scales from black to white represent a change in A of 120 - 130°. The scale bar has a length of 25/im. (redrawn from [36])...

Infrared Imaging and Mapping for Biosensors, Figure 1 (a) Principle of ellipsometric mapping measurement Due to reflection at the sample, the... 

Munteanu, S., N. Garraud, J. P. Roger, F. Amiot, J. Shi, Y. Chen, C. Combellas, and F. Kanoufi. In situ, real time monitoring of surface transformation Ellipsometric microscopy imaging of electrografting at microstructured gold surfaces. Anal. Chem. 85, 2013 1965-1971. 

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