Infrared coating materials silicon

It should be possible to see the chemical products in the infrared spectra of the thin film. In order to look at the small quantities of material involved, it was necessary to do in situ exposures of the resist coatings on silicon wafers in a Fourier transform infrared spectrophotometer. The technique was capcUsle of following the loss of quinone and the formation of ketene with considerable success. By purging the wafer in the chamber for some time in the presence of dry nitrogen, it was possible to observe a stable ketene signal even hours after the exposure. While these experiments were not quantitative, they did give two pieces of... 

A problem that may be encountered when analyzing a solid sample by transmittance spectroscopy is radiation scattering. Employing reflectance spectroscopy can sometimes reduce this problem. With this technique, the infrared spectra of most solid materials are easily obtained with little or no sample preparation. Spectra of a wide range of solid samples can be characterized with this technique, such as coatings on beverage containers and silicon wafers, polymer films, or other intractable samples. The reflectance technique, however, is less sensitive than the transmittance technique since about 80 /o of the infrared radiation is lost after being reflected off the sample surface. 

Seifert, L.M. and R.T. Greer, Evaluation of in vivo adsorption of blood elements onto hydrogel-coated silicone rubber by scanning electron microscopy and Fourier transform infrared spectroscopy. Journal of Biomedical Materials Research, 1985, 19, 1043-1071. 

Liquid silicone rubbers have also been used in some extruded applications. Vulcanization of the extruded material may be carried out by using infrared heaters or circulated hot air. The process has been applied to wire coating, ignition cables, optical fibers, various tapes, and braided glass-fiber sleeving, as well as for covering delicate products. 

Carbon film, which is chemically inert, can be applied as protective coating and antireflection layers for optical components for the infrared range and laser devices, wear protection, dielectric materials, coatings on fusion reactor walls, etc. Superlattices of a-C H and a-Si H have been obtained, and compound layers of a mixture of carbon and silicon have been grown. 

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