Atmospheric plasma deposition of coatings using a capacitive discharge source

In this paper, a review is provided of the plasma-enhanced (PE)CVD of thin films using an atmospheric-pressure (AP) capacitive discharge source. This source is unique in that the organometallic precursors are fed downstream of the plasma, where reactions occur exclusively between neutral molecules, radicals, and the substrate surface. As a result, the properties of the films differ from those obtained in low-pressure (< 1 torr) gas discharges. For example, glass may be deposited on plastic with no carbon contamination and less than 15 mol-% hydroxyl groups, yielding material with good scratch protection. Silicon nitride and amorphous hydrogenated silicon films have also been prepared by AP-PECVD. These material processes further illustrate the unique attributes of this new deposition technology.