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The approach to reduce the costs of electronic circuits will be the transition of LSI‐circuits to VLSI‐circuits, introducing another order of magnitude to the complexity and density of these circuits. The influence of this will be similar to the transition of discrete transistors to integrated circuits. VLSI‐circuits are, in general, digital circuits and therefore the passive components used in analogue circuits will be used in smaller quantities, just as the discrete transistors will change from small signal to power. Sensors and display units as liquid crystals will gain importance and need to be interconnected in an economic way. Competing with printed circuit boards are hybrid circuits, but these have not yet found general application due to the high innovation rate of integrated circuits. However, special applications as high frequency circuits are cost effective. A cost breakdown of electronic equipment shows that due to the introduction of LSI and VLSI circuits the relative costs of PCB's are rather high and that economics will force the introduction of new technolgies to achieve the correct cost balance.

This paper deals with the design of PCBs, using the dielectric properties of solder mask as an insulation layer to protect boards and components; the elimination of selective solder filling of component holes; the protection of via holes during soldering, and the preparation of artwork, with particular attention to design tolerances using dry film solder mask. Future prospects in PCB design, employing dry film solder mask, are also discussed.