A plasma generator includes several plasma sources distributed in an array
for plasma treatment of surfaces. Each plasma source includes first and
second conductive electrodes. Each second electrode has a gas passage
defined therein, and one of the first electrodes is situated within the
gas passage in spaced relation from the second electrode, with each gas
passage thereby constituting the free space for plasma generation between
each pair of first and second electrodes. An insulating layer is
interposed between the first and second electrodes to facilitate plasma
formation via dielectric barrier discharge (DBD) in the gas passages
between the first and second electrodes. The first electrodes may be
provided in a monolithic structure wherein they all protrude from a common
bed, and similarly the second electrodes may be monolithically formed by
defining the gas passages within a common second electrode member. The
first electrode bed may then be situated adjacent the second electrode
member with its first electrodes extending into the gas passages. The
space between the first electrode bed and the second electrode member
defines a plenum space onto which the gas passages open. The plenum space,
and thus the gas passages, may then be provided with process gas to
generate plasma within the gas passages between the first and second
electrodes. Plasma ejected from the gas passages will impinge upon and
treat an adjacently-situated workpiece without the need to pass the
workpiece through the gas passages, and thus the size of the workpiece to
be treated is not limited by the size of the gas passages (i.e., the free
space wherein plasma is generated). The ability to utilize
monolithically-formed first electrodes and/or second electrodes allows for
significantly denser placement of plasma sources in arrays, thereby
leading to more complete plasma treatment of surfaces.
