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90 I-CONNECT007 MAGAZINE I JANUARY 2026 ment on this process by 2030. Given the lack of success of my prognostications over the past few years, I hope this is not a death sentence. What Are the Most Difficult Challenges Ahead? There are two perspectives to consider when examining the most challenging aspects of PCB fabrication: technical and business. The answer to both is within the question itself. The rapid advancement of technology is the biggest chal- lenge. You no sooner meet one challenge than something comes along that makes that solu- tion obsolete. As an equipment supplier, it is chal- lenging to stay ahead of the curve and be proac- tive rather than reactive. It is desirable to be ready for the next wave of technology but that is difficult to do when the next wave of technology arrives before you're finished with the previous wave. Even when the technological change is relatively slow, the degree of change can be unanticipated. A good example is transport technology: trans- porting the circuit board on a horizontal conveyor through an etch chamber where we spray it with hot acid that is much heavier than water (specific gravities between 1.22 to 1.48 vs. 1.00 for water). When I started in 1974, the typical circuit board had a 0.062" core of FR-4 fiberglass, and our conveyor system had one-inch diameter wheels spaced two inches apart on thin titanium conveyor rods, with the conveyor rods also spaced two inches apart. This was designed to transport a rigid panel through the etcher with minimum interfer- ence to the lower sprays. A customer brought in a test sample with an 0.010" FR-4 core. It was a disaster because the 0.010" core was flexible enough so that the signal-over-signal layers would slip between the conveyor rods into the etcher sump. This necessi- tated a change to the conveyor design, where the rods were spaced closer together, and the wheel diameters were increased, allowing them to over- lap from rod to rod and prevent panels from slip- ping between them. We called it the "ultra-thin" conveyor (and still do) because we wondered how much thinner they could make a fiberglass core. As it turned out: much thinner. It wasn't long before we saw 0.002" FR-4 cores that forced us to move the conveyor wheels closer together for support, leading to a slight slowdown in etch rate (blas- phemy at the time, but it had to be done). That was acceptable because they certainly couldn't make fiberglass cores thinner than 0.002", but they could use materials like Kapton and Pyralux, which were not only thinner but also flex- ible. These materials would transport okay, but the weight of the etch solutions tended to emboss creases into the panels from the wheel rims, forc- ing us to increase the width of the wheel rims to provide still more support, but also slowing the etch rate a little more. Now, I am trying to anticipate even more flexible materials and come up with a conveyor system that will run substrate material with the thickness and flexibility of tissue paper up to boards with thick- nesses of 0.25" and more in the same equipment. It goes without saying that using leaders taped to the leading edges of flexible panels is not an option. I would like to think that I can come up with a solution that also addresses future transportation issues. The problem is that I can't conceive of any material that will be more difficult to work with than what we have already. At the same time, I'm confi- dent that someone will come up with something. In short, it's hard to predict or prepare for changes that haven't even been thought of yet, but the escalating rate of change in the industry makes these changes inevitable. We will be forced to continue reacting to these changes rather than anticipating them. PCB007 Don Ball is a process engi- neer at Chemcut. To read past columns or contact Ball, click here. T H E C H E M I CA L C O N N ECT I O N