Oxygen plasma etching of hydrocarbon‐like polymers: Part I Modeling

This work on the etching of polymers in oxygen plasmas begins with a general review of experimental data and modeling attempts. Result analysis leads to an extended etching model based on the description of polymer surfaces composed of chain segments randomly distributed and taking into account the microscopic structure of polymers at the atomic and molecular level. Experimental data also suggest that thermally activated desorption of CO, in addition to CO2 desorption, and UV‐induced etching, in addition to ion‐induced etching, must be incorporated in the modeling. The analytical results confirm the impossibility to reach perfect anisotropy in presence of UV‐induced desorption and also to determine directly from Arrhenius plots the activation energies for CO and CO2 thermal desorption. In plasma etching processes, polymeric chains can be schematically described as carbon chain segments with single bonds between successive (black) carbon atoms and two available adsorption sites per carbon atoms: a) front view; b) side view; c) top view. Such a one‐dimensional description is more consistent with the microscopic reality than the two‐dimensional character attributed so far to polymer surfaces.