Apparatus for wet processing of a planar workpiece, device for a cell of the apparatus and method of operating the apparatus

Device for a cell of an apparatus for wet electrolytic treatment processing of a planar workpiece, comprising:

• a structure comprising first and second walls,
• wherein the workpiece is movable in a central plane through a space internal between the first and second walls in a first direction (y),
• wherein apertures for introducing pressurised liquid between the first and second walls are provided on opposite sides of the central plane and facing the central plane,
• wherein the apertures are distributed in the first direction (y) and in a second direction (x) transverse to the first direction (y),
• wherein discharge openings for the liquid to leave the space are defined on opposite sides of the space, seen in the second direction (x), along an extent of the space in the first direction (y), and
• wherein the first and second walls form barriers to liquid flow from the space in a direction (z) perpendicular to the central plane,
• wherein
• channels are provided through the first and second walls, each channel arranged to conduct liquid to a respective one of the apertures;
• and
• at least one liquid distribution space extending in the second direction (x) across inlets of the channels is delimited by a barrier wall disposed external to and on an opposite side of at least one of the first and second walls away from the space, wherein the at least one liquid distribution space has a height defined by the barrier wall, and said height decreases with respect to at least one of the first and second walls towards an opposite edge and forms a closed end of the liquid distribution space.