Multi-step reactions mechanism for F atoms interactions with organosilicate glass and SiOx filmsстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
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Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 2 ноября 2016 г.
Аннотация:Ab initio approach with density functional theory (DFT) method was used to study F atoms interactions with organosilicate glass (OSG) based low-k dielectric films. Because of complexity and significant modifications of OSG surface structure during the interaction with radicals and etching, a variety of reactions between the surface groups and thermal F atoms can happen. For OSG films etching and damage we propose a multi-step mechanism based on DFT static and dynamic simulations and consistent with the previously reported experimental observations. The important part of the proposed mechanism is formation of pentavalent Si atoms on the OSG surface due to a quasi-chemisorption of the incident F atoms. The revealed mechanism of F atoms incorporation into the OSG matrix explains the experimentally observed phenomena of the fast fluorination without significant modification of the chemical structure. We demonstrate that the pentavalent Si states induce the weakening of adjacent Si–O bonds and their breaking under F atoms flux. The calculated results allow us to propose a set of elementary chemical reactions of successive removal of CH3 and CH2 groups and fluorinated SiOx matrix etching