Insight into the Reaction Scheme of SiO sub(2) Film Deposition at Atmospheric Pressure

• Published in: Plasma processes and polymers Vol. 10; no. 12; pp. 1061 - 1073
• Main Authors: Ruegner, Katja, Reuter, Ruediger, Ellerweg, Dirk, de los Arcos, Teresa, von Keudell, Achim, Benedikt, Jan
• Format: Journal Article
• Language: English
• Published: 01.12.2013
• Subjects: Atmospheric pressure
• ISSN: 1612-8850; 1612-8869
• DOI: 10.1002/ppap.201300059

Characterisation of an atmospheric pressure microplasma jet in combination with simulations have been used to determine reaction mechanism of SiO sub(2)-like film formation and reaction rate constants for several gas phase reactions in the He/hexamethyldisiloxane (HMDSO)(/O sub(2)) plasma chemistry. Using a variable-length quartz tube, the gas residence time in the plasma effluent could be well controlled without changing plasma properties. A possible reaction scheme has been developed. Deposition rates, deposited profiles, carbon content of the films and the depletion of HMDSO could be reproduced by the simulation. The simulation indicates that HMDSO in He(/O sub(2)) plasma dissociates preferentially into (CH sub(3)) sub(3)--Si--O and Si--(CH sub(3)) sub(3), where the former radical serves as a main growth precursor. Reaction rates and surface reaction probabilities for the deposition process of SiO sub(2) by means of atmospheric pressure plasma jet are estimated by comparing experimental studies with simulation of the proposed reaction scheme.