Ellipsometric studies

Ellipsometry can be sensitive to layers of matter only one atom thick. For example, oxidation of freshly cleaved single-crystal graphite can be monitored from the first monolayer and up. The best thicknesses for the ellipsometric study of thin films are between about 1 nm and 1000 nm. Although the spectra become complicated, films thicker than even 1 pm can be studied. Flat planar materials are optimum, but surface and interfacial roughness can be quantitatively determined if the roughness scale is smaller than about 100 nm. Thus ellipsometry is ideal for the investigation of interfacial surfaces in optical coatings and semiconductor struc-... 

The results of the ellipsometric study are presented in Table 9. As is clear from the table, the resultant average thickness of the semiconductor layer, obtained from one bilayer precursor, is about 0.8 nm. This value can be considered the thickness resolution of this technique. It is worth mentioning that among the available techniques, only molecular beam epitaxy allows one to reach such resolution. However, the proposed technique is much simpler and does not require complicated or expensive equipment. 

Redondo A, Ticianelli EA, Gottesfeld S. 1989. Ellipsometric studies of conducting polymers. Synth Met 29 E265-E270. 

The evidence for two reasonably well defined layers comes primarily from electrochemical studies, ellipsometry and Raman spectroscopy, The ellipsometric studies of Ord and DeSmet (1976) show good evidence of an abrupt... 

Ellipsometric Study of Adsorption of Polyelectrolyte onto a Metal Surface... 

Ellipsometric studies. The thicknesses of the unreated silane surface films 1-5 were initially determined and were found to be close to the values expected for monolayer level coverages (see Table 1 for details). Upon treatment of the surfaces with the guest amine or acid solutions, all the surfaces exhibited thickness values corresponding to multilayer coverages by both of these guest molecules. However, when each of the treated surfaces was washed thoroughly... 

Gebhard and Killmann69 reported an ellipsometric study of the adsorption of polystyrene onto various metal surfaces from theta solvents, M ranging from 76 x 103 to 340 x 103. A proportionality between t,ms and M1/2 was also observed, and the adsorb-ance was found to increase with rising M. 

F. Heslot, A. M. Cazabat, and P. Levinson, Dynamics of wetting of tiny drops Ellipsometric study of the late stages of spreading, Phys. Rev. Lett. 62, 1286-1289 (1989). 

Therefore, I devised a way to carry out ellipsometric studies generally applicable to surface films and I discovered that well buffed Simonize films were only about a molecule thick. Simonize films were a dramatic illustration of the effectiveness of boundary lubrication This finding encouraged me to investigate the films by electron diffraction and the diffraction patterns showed that Simonize films were remarkably well-organized semicrystalline aggregates as opposed to some of the short-lived cheap competitors which gave diffraction patterns indicative of chaotic heaps of molecules. 

E. D. Palik, V. M. Bermudez, and O. J. Glembocki, Ellipsometric study of the etch-stop mechanism in heavily doped silicon, J. Electrochem. Soc. 133, 135, 1985. 

L. Young and F. G. R. Zobel, An ellipsometric study of steady-state high field ionic conduction in anodic oxide films on tantalum, niobium and silicon, /. Electrochem. Soc. 113, 277, 1966. 

Bailes M., Bohm S., Peter L. M., Ridley D. J. and Greef R. (1998), An electrochemical and ellipsometric study of oxide growth on silicon during anodic etching in fluoride solutions , Electrochim. Acta 43, 1757-1772. 

Zerbino and Sustersic [309] have presented electrochemical and ellipsometric studies of dopamine adsorbed on gold electrodes in aqueous H2SO4 solutions of pH = 1. 

Malmsten, M. andLindman, B. (1989) Ellipsometric studies of cleaning of hard surface. Relation to spontaneous curvature of the surfactant monolayer. Langmuir, 5, 1105. 

Poncet C, Tiberg F, Audebert R. Ellipsometric study of the adsorption of hydrophobically modified polyacrylates at hydrophobic surfaces. Langmuir 1998 14 1697-1704. 

Finally we only mention that, for example, calorimetric investigations [72, 395], LEED [91], high-energy electron diffraction [313], neutron diffraction [45, 371], high-resolution electron energy loss spectroscopy [304], and ellipsometric studies [111, 147, 366] were extended much beyond the fully compressed N2 monolayer into multilayer and film regimes. 

Baba, M. Gottesfeld, S. "Ellipsometric Study of the Polymeric Surface Films Formed on Platinum Electrodes by the Electroxida-tion of Phenolic Compounds", Surf. Sci., 96, pp. 461-475,... 

Rella R., Siciliano R, Valli L., Spaeth K., and Gauglitz G., An ellipsometric study of LB films in a controlled atmosphere. Sens. Actuators B, B48, 328-332, 1998. 

Sharp JS, Forrest JA (2003) Dielectric and ellipsometric studies of the dynamics in thin films of isotactic poly(methylmethacrylate) with one Ifee surface. Phys Rev E 67 031805... 

S. Yukioka, K. Nagato, and T. Inoue, Ellipsometric studies of mutual diffusion and adhesion... 

In the first two Sections, the basics of the Brewster angle ellipsometry and the operation principles of the photoelastic modulator (PEM) based ellipsometer will be overviewed. In the following, three different ellipsometric studies of the solid-liquid crystal interface wiU be presented. 

Ellipsometric studies at p=2xlQ- Torr showed that PH3 was adsorbed on the (110) plane of GaP single crystals. The fractional coverage (number of PH3 molecules per surface atom) was 0.2 at room temperature [6]. The adsorption process on GaP powder (specific surface area 1 m /g) in the pressure range 5 x10 to 5 x10" Torr involved a fast uptake followed by a slow continuous logarithmic adsorption to a fractional coverage exceeding about 0.2 [7]. 

The story of ellipsometric studies of polyaniline (PA) shows that increasing sophistication in the technique has led to successively more valuable information from experimental data. In early ellipsometric studies of PA film growth, and subsequent potential cycling, either single A (633 or photoelastic modulation (650-350 ellipsometry (where A and IP only were measured) were... 

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