Electrically Mediated Microetching

摘要

The need for smaller PCBs has resulted in increased packing density on the boards along with finer lines, lower line spacing and smaller pads. Currently, spray etching is the industry standard for patterning copper on PCBs. Below line widths of about 75 μm, spray etching does not work well due to mass transport limitations. Other etching processes, such as direct current (DC) and mechanical etching, are under development. To date, these have exhibited low etching rates and damage to the PCB from contact with the brushes.