Characterisation of micropores in plasma deposited SiOxfilms by means of positron annihilation lifetime spectroscopy
- 18 November 2020
- journal article
- research article
- Published by IOP Publishing in Journal of Physics D: Applied Physics
- Vol. 53 (47), 475205
- https://doi.org/10.1088/1361-6463/aba8ba
Abstract
The effect of average incorporated ion energy and impinging atomic oxygen flux on the structure and permeability of SiO(x)thin films by a microwave driven low-pressure discharge with additional radio frequency bias is studied by means of positron annihilation lifetime spectroscopy (PALS) and complementary analytical approaches. The film growth and structure were controlled by the particle fluxes. A correlation between the pore sizes and pore size distribution as measured by PALS and the adjusted plasma parameters was established. The corresponding barrier performance was measured by oxygen transmission rate and could be explained by the pore size distribution. The dominant pore size characteristic for dangling bonds within the SiOx-network was found to be in the range of 0.8 nm. The chemical composition and morphology were analysed by means of x-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy diffuse reflectance measurements and atomic force microscopy. It was observed that a combination of both an increase in incorporated energy per deposited Si atom and low oxygen to silicon ratio resulted in an enhanced cross-linking of the SiO(x)network and thereby led to a decrease in micropore density and to a shift of the pore size distribution function to lower values.Keywords
Funding Information
- Deutsche Forschungsgemeinschaft (SFB-TR87)
This publication has 66 references indexed in Scilit:
- Plastics recycling: challenges and opportunitiesPhilosophical Transactions Of The Royal Society B-Biological Sciences, 2009
- Silicon Oxide Permeation Barrier Coating and Plasma Sterilization of PET Bottles and FoilsPlasma Processes and Polymers, 2009
- PALSfit: A new program for the evaluation of positron lifetime spectraphysica status solidi (c), 2007
- Development of Plasma Polymerised SiOx Barriers on Polymer Films for Food Packaging ApplicationsPlasma Processes and Polymers, 2007
- Thin-Film Permeation-Barrier Technology for Flexible Organic Light-Emitting DevicesIEEE Journal of Selected Topics in Quantum Electronics, 2004
- Structure of low dielectric constant to extreme low dielectric constant SiCOH films: Fourier transform infrared spectroscopy characterizationJournal of Applied Physics, 2003
- Etching mechanisms of low-k SiOCH and selectivity to SiCH and SiO2 in fluorocarbon based plasmasJournal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, 2003
- Ortho-positronium lifetime studies of free volume in polycarbonates of different structures: influence of hole size distributionsMacromolecules, 1993
- Structure of rings in vitreousPhysical Review B, 1993
- Evidence of Si–OH species at the surface of aged silicaJournal of Vacuum Science & Technology A, 1992