A process designed to riove epoxy-resin smear from inner layer copper interfaces. Smear occurs during drilling.

The removal of friction-melted resin and drilling debris from a hole wall.

When multilayer printed circuit boards are drilled, the drill cuts through lands of copper on the inner and outer layers. Resin from the base laminate is smeared over the exposed copper where plated copper must eventually form a connection. This resin must be removed to ensure a sound electrical connection will be made by the plated copper. This is the desmear process.