Thermal Stability of Alkyl-Grafted Surfaces

Two desorbed methylene groups are thought to couple, forming an ethylene molecule [171]. Such a mechanism is similar to the one considered by Faucheux et al. (1.9) and regarded as secondary. The apparently larger contribution of this reaction pathway in the experiments of Jaeckel et al. can plausibly be attributed to the different sequence of the annealing temperatures in the two experiments [171]. 

Si surface (c,d) upon successive annealing at 300 °C, 440 °C and 530 °C. The spectra were recorded at a photon energy of 330 eV. After Ref [171], (e-f) Change in the IR transmission spectrum of a methyl-grafted porous sihcon layer upon successive anneahng by increments of 50 °C from 50 °C to 550 °C (there is no measurable change up to ca. 400 °C this is why not all of the spectra are shown). After Ref [173]. (a-d) Adapted and reprinted with permission from Ref [171]. Copyright 2007 by American Chemical Society. 

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