Pattern Plating

Production of HDI circuitry (< 50 µm lines/spaces) by laser structuring of conventional photo resist

Laser structuring can be easily integrated into the Pattern Plating process, in order to manufacture areas of the finest resolution (< 50 µm) on the printed circuit board. Areas of small pattern resolution are exposed first conventionally by films. High density circuit areas are then exposed at the same time applying any structures. After developing the dry resist the areas are then structured by means of the laser. Then, following the usual Pattern Plating process, copper is plated to form the final copper thickness, tin is plated to provide the etch resist, the dry resist is stripped and etching of the initial copper generates the conductive tracks.

Advantages of laser structuring

• by etching only the thin initial copper layer the finest track widths are possible
• efficient decrease of PAD diameters as well as track and gap widths
• especially suitable for small areas with high density devices i.e. large areas are produced by conventional photolithography, small areas are structured by means of laser
• automatic correction of positional errors and process-caused material distortion by registration of the fiducials and on-line scaling.
• compatible with standard plating and etching processes
• structuring directly from CAD data