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Flexible Thinking: The Value of Experience

For many people, December is a month in which to reflect on the experiences and lessons encountered and learned over the past year. As the years pass, I am increasingly thankful for the many experiences that have brought me to this point. In sitting down to collect and share my thoughts, what first came to mind was a timeless story about the value of experience. It goes something like this.
 
A young engineer asks a mentor a question about a problem that he has been pondering for some time. The older engineer listens attentively and then posits a possible solution to the problem. The young engineer tries the suggestion, and it works the first time. He thanks the mentor for sharing this wisdom, asking, “How did you know that would work?” The older engineer responds, “From my experiences.” The young apprentice pressed for more detail, wanting to understand how the mentor had obtained the wisdom to intuit the answer so quickly; the mentor sagely adds, “From my bad experiences.”
 
Looking back at my almost half-century of experiences, I can attest to both the validity and the constancy of this story from both ends of that humorous, but experientially, true tale. I was fortunate to have had several excellent and very experienced engineers as mentors from an early stage in my career. They were largely members of the “Greatest Generation,” and many were veterans of World War II and the Korean War. I was a veteran as well, but of Vietnam; thus, we had a common bond that allowed for a friendly and interactive relationship. 
 
I was also fortunate to have worked in an engineering “bullpen” in a manufacturing technology group for the manufacture of electronics for Boeing Aerospace. Our shared office space consisted of desks that were three across and eight rows deep, which gave me instant access to an incredible brain trust, who could provide answers to my questions or direct me to a reference where answers could be found (these cherished colleagues were my early version of the internet but with personalities). Printed circuit fabrication was a primary focus of our group, and as those who fully comprehend and appreciate the complexity of PCB manufacturing will attest, it took all manner of engineering and technical skills and disciplines to develop and service the processes required to make the desired products.
 
Printed circuits are arguably one of the most complex and process-intensive products made today—even more so than semiconductors, one could argue. Consider the following skills required today:
 
• Electrical/electronic engineers and skilled technicians must define the functions,  ?design, and layout the product
• Packaging engineers and technicians must design the envelope into which the electronics will be placed
• Mechanical and material engineers must determine what properties the PCB substrate needs have to function for the application
• Chemists, chemical engineers, and skilled technicians must operate and maintain  ?the numerous chemical processes involved in PCB manufacturing
• Project and manufacturing engineers must plan the manufacturing flow
• Process engineers and skilled technicians are required at every step to execute the seemingly endless number of process steps and variations that might be required to complete the product
• Metallurgical scientists and engineers must test, evaluate, and bless both the  ?assembly process and the materials used
• Laboratory test engineers and technicians must monitor, test, and evaluate the  ?end-product and its fitness for use
 
I can think of a few other disciplines not mentioned, but the short list provided should provide ample testament to the complexity.
 
People of such varied skills were responsible, from the earliest days of the industry, to weave together materials, equipment, and processes, often with origins far from the tasks they have been adapted and are now being used for. Consider the few following industries that have been drafted into service to make today’s most advanced printed circuits: 
 
• Lamination industry: Lamination presses for flex and multilayer circuits
• Graphic arts industry: Screen printing and photolithography used for imaging
• Machining industry: NC drilling, routing, punching, and stamping 
• Plastics plating industry: Electroless and electrolytic plating of vias
• Aerospace industry: Vacuum lamination and advanced composites
• Shoemaking and paper industries: Steel rule die cutting of flex circuits
• Microelectronics industry: Metal sputtering and plasma cleaning and etching
• Applied physics: NC laser drilling and cutting
 
Over time, these items have adapted to more specifically address the changing needs of printed circuit manufacturers. Today, the PCB materials, processes, and equipment industries constitute multi-billion dollar market. However, the printed circuit is, unfortunately, too often underappreciated in its continuing role as the virtual foundation of all modern electronics. Without PCBs, semiconductor devices would have no means of interconnecting and performing the designed end function and purpose/mission. They play a vital and irreplaceable role in all electronics manufacturing.
 
Given global society’s increasing reliance and dependence on electronics for getting through the day, we are all, by extension, reliant on PCB technology. Therefore, it is imperative that we not lose sight of the important role printed circuit technology continues to play in our lives. It is also important to keep pace with the advances of semiconductor technology to provide and ensure complete and uninterrupted reliability of the electronics we all increasingly depend on. 
 
In closing, I’d like to share another short story. It comes from an interview given by famed Swedish film director Ingmar Bergman, which I first encountered some 30 years ago: “Old age is like climbing a mountain. You climb from ledge to ledge, and the higher you get, the more tired and breathless you become, but your views become more expansive.” Enjoy your climb.

This column originally appeared in the December issue of Design007 Magazine in the FLEX007 section.