Method and apparatus for electrolytically treating a board-shaped substrate comprising shielding edge regions of the substrate during electrolytic treatment

Abstract

The apparatus according to the invention is used for electrolytically treating a board-shaped substrate to be treated, preferably printed circuit boards, in a continuous system, through which the item to be treated is guidable in a plane of conveyance in a substantially horizontal direction of conveyance, the apparatus having counter-electrodes (,), which are situated substantially parallel to one another opposite the plane of conveyance, and screens (,) for shielding from high current density fields in the edge region of the item to be treated (,), said screens being disposed between the plane of conveyance and the counter-electrodes, the screens each being in the form of at least two flat portions (,), which are disposed substantially parallel to each other, one portion (,) of the screens being disposed so as to lie opposite the plane of conveyance, and the other portion (,) being disposed so as to lie opposite the counter-electrodes, and the screens being mounted so as to be displaceable in a direction (,) which extends substantially parallel to the plane of conveyance and substantially perpendicularly relative to the direction of conveyance (,). The usable region of printed circuit board blanks can be extended by this apparatus down to an edge of about 12 mm, where the required tolerance of the layer thickness of the deposited metal cannot be maintained.