PCB cost reduction through innovation

Martin Stumpp, HPTec GmbH, outlined the principles for making cost calculations on the drilling process (and the factors that needed to be included) in his presentation at the EIPC Summer Conference.

PCBThose key cost factors related to the machine, the tools and the operator. As an example, he presented a cost calculation - comparing the costs of drilling 0.4 mm and 0.2 mm holes- The move to smaller holes meant reduced drill life times and reduced stack heights, which in turn led to increased costs. Moving from FR4 to a ceramic PCB required similar changes and the costs increased by a factor of four, he added.

However, a number of costs are variable and can be influenced; drill lifetime extension via the use of high performance tools or drill repointing. Increasing the bit in feed and retract speeds during drilling, manufacturers would be able to reduce process costs by 16%, he estimated; increasing the stack height from 2 to 3 could reduce the costs by 20% (increase of stack height offered the biggest saving).

The final part of his presentation focussed on the possibility of coating tools with diamond or by PVD coating. These coatings were around 1 μm thick and gave eductions in tool wear, leading to a two or three times increase in lifetime. It was predicted that in the next two years there would be many coated tools available.