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Regular readers hopefully do not need to be convinced that flexible circuit technology is one of the most enabling technologies for making interconnection. In the world of electronics, flexible circuits have continued their steady climb from relative obscurity half a century ago to center stage in the world of electronic interconnections. The reasons for their popularity are numerous:
- They are thin and light
- They can be bent, folded, or flexed
- They can offer superior electrical performance
- They can provide a highly reliable interconnection structure
- They can make possible structures that cannot be achieved by any other method (at least not as easily or cheaply)
With such an impressive list of benefits, it might seem as though the technology has reached its improvement limits. However, the principle of continuous improvement does not rest, and it demands that we persist in our efforts to do and make things better over time.
The great Irish playwright, critic and Noble Prize-winning author George Bernard Shaw is credited with saying, “Some look at things that are and ask why. I dream of things that never were and ask why not?” It is clear from the order of his statement that Shaw appreciated the importance of “why” and that it is one of the most often used by children trying to understand the world. Without asking that important and fundamental question of “why?” the question of “why not?” (which is the one that truly sparks the inventive spirit) cannot logically follow. Indeed, innovation is commonly a product of observation and these “why” and “why not” questions.
Such questions pressure the curious mind into action, hopefully resulting in one seeing (or dreaming of, as Shaw suggests) either the missing piece or alternatively the boundaries of empty space that define the missing piece. To be certain, these questions will, at some point, also cause a cascading chain of other common questions: what, how, where, who, when, and how much, which need also to be answered to complete the circle. Thus, the all-important first challenge that confronts us is to try and see what is not there and to then set about turning it from a concept to something concrete—from vision to reality.
With that preamble staging, and our collective challenge to “fill in the blank,” it is worth taking a very short “mind walk” to uncover or illuminate the missing pieces that await their moment of discovery. For an exercise, we can apply this notion to flex circuit technology and see what it yields.
First, it is worth noting that once we become familiar with something, no matter what its nature, we become wedded to our perceptions of it—and technology is not immune. Flexible circuit technology, we know, is a highly enabling technology and it has many facets to it: materials, design tools and practices, manufacturing processes and methods, assembly tools and methods, testing equipment and protocols, etc. While the interdependence and interplay between these elements must be considered (changing one thing will normally impact another), it should not be an initial constraint. One should not be fearful of (and indeed should be encouraged to) wandering off the beaten path. To be sure, by not staying on the main streets there will be some apparently blind alleys found, but these alleys can sometimes yield some unexpected treasure that, while not of value to the current effort, could be useful in an unrelated effort later. Another thing to avoid early on is any consideration of cost. It is often the case that a process or device is very expensive at the outset but that the price will come down with experience and greater numbers of participants.
Those points aside, we can now quickly apply the “why” questions to some aspects of flexible circuit technology to see what it yields. Don’t look for answers to follow here; there is no ability or intent to answer the questions the reader might ask. They are yours to ponder on your own and hopefully come up with some “why not” ideas of their own. Consider then the following:
- Why do we use only certain materials?
- Why do we need holes?
- Why do we use cover layers?
- Why do we need lamination?
- Finally for a little bit of controversy, why do we even need flexible circuits?
There are no right or wrong questions or answers; they are simply questions, ones that might help us all to break loose from our mental chains and think in new directions and dimensions. Since this column offered up an early quote from a genius, it seemed appropriate that it should end with a quote from another great mind, Supreme Court Justice Oliver Wendell Holmes, who astutely observed, “Man's mind, stretched by a new idea, never goes back to its original dimensions.” It seems doubly fitting, knowing that stretching also helps one to stay flexible in body as well.
- John F Kennedy paraphrased Shaw in his memorable first and, sadly, only inaugural speech and often is given credit as the first to present the idea.
This column originally appeared in the August 2021 issue of Design007 Magazine.