Silicon oxide coated polymer films and low pressure pecvd methods for producing the same

A process for the production of layers based on silicon oxide on a polymer substrate, comprising:

• providing the polymer substrate,
• providing a low-pressure PECVD device comprising at least one linear hollow-cathode plasma source, each source comprising at least one pair of electrodes connected to an AC, DC or pulsed DC generator, for the deposition of said films on the substrate,
• applying an electrical power to the plasma source, so that a power density of the plasma is between 1 kW and 50 kW per linear meter of plasma source, and
• applying, to the polymer substrate, a gaseous precursor of oxides of silicon at a flow rate of between 50 and 700 sccm per linear meter of the plasma source, the gaseous precursor of oxides of silicon being injected in between the electrodes of each electrode pair and in between the two pairs of electrodes and a reactive gas based on oxygen or on oxygen-comprising derivatives at a flow rate of between 1500 and 4000 sccm per linear meter of the plasma source, the reactive gas being injected in the electrodes of the hollow cathode plasma source.