My style in the kitchen could best be described as slapdash. It’s not that I dislike cooking (far from it!), but if I’m cooking, I’m likely hungry. As you might imagine, this method doesn’t lend itself to easily repeatable recipes. I’m notorious for substituting or removing ingredients on-the-fly depending on what’s in the pantry. My signature cookbook would be more of a feeling than a cherished recipe handed down over generations. Sometimes I wish I had taken better mental notes of how a dish came together so I could easily reproduce it.
One of the most important elements of mass production is adherence to a gold standard. Whatever you’re selling, consumers are expecting more-or-less the same product or experience every time. Repeatability requires design intent to be carried through manufacturing, ensuring that the design is translated directly, without alteration or ambiguity. The copy exact process is a generalized descendent of Intel Copy Exactly!’s method of producing chips. PCB production facilities use it as a foolproof method for establishing compliance across the varied stages of manufacturing.
Copy Exact Requirements for PCB Manufacturing
Mass production is difficult, and mass PCB production is even harder still. The most arduous task for a manufacturer is exporting design processes to a facility with high production capabilities to integrate additional throughput seamlessly. Copy exact attempts to address this last issue by extensively detailing and documenting the granular details of production such that these practices can be readily implemented without a reduction in quality or yield with the onboarding of a new facility.
Think of copy exactly like taking apart and reassembling an intricate mechanical device on an industrial scale: detail analysis should be performed before recreating the original, lest manufacturing ends up with the process-level equivalent of leftover screws and no idea where to place them.
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Copy exact stands in stark contrast: every detail counts, so much so that the directive requires recording every possible variable unless there is a compelling reason not to. Some reasons might include when it’s either impossible to perform, or the improvements gained by alteration of the set-up greatly outweigh any potential loss of description accuracy.
If the idea of simply copying the work of a complex system sounds like an underwhelming design criterion, copy exact processes require a four-point check to roll out properly:
- Copy exact first has to match the physical inputs, no matter how seemingly mundane. This step includes obvious candidates like material and energy inputs into the system and the shape of gas lines, and other parameters that might otherwise fail to register as worthwhile tracking
- Next comes process step matching. Individually tracked characteristics, such as the capacitance between layers following lamination, might be measured here.
- Third is a comparison of structures. PCB manufacturers could check the dimensions and impedance of a fabricated trace line.
- Lastly is the direct comparison of the product between the two facilities. That could be the bare board or PCB to check for all identical qualifications.
Importantly, copy exact’s criteria increase in specificity and difficulty of manufacture as it climbs the verification levels. The process verification is two-fold. First, it gently ramps up production requirements logically and with difficulty in mind. Attempting to compare products first, for example, is unlikely to result in a matching set. Still, it cannot be ascertained whether the design of the manufacturing process was identical or whether compensations were made to ensure the products matched. This distinction is important: copy exact processes result in identical products because the processes are identical. In other words, it’s a tautological design method that forces symmetrical build-up of manufacturing.
How the Copy Exact Process Pays Dividends
PCB production builds in complexity. Copy exactly ensures precise production that can operate with high quality and yield faster than traditional process design applications. Consider the complexity of fabricating exceedingly small trace widths for an HDI board: copy exact helps manufacturing sites more rapidly reach a level of minimum competence required for industrial manufacturing.
Without it, the run-up to acceptable production quality is often more treacherous, which manufacturers can ill afford with large production lots and tight deadlines. Time spent validating processes before production is a perfect example of “measure twice, cut once,” where manufacturing facilities also benefit from continuous, uninterrupted production.
Keeping manufacturing consistent between facilities can also reflect the different volumes available. An NPI board built at a facility should match the PCB at a mass production site, excluding any revisions made in the interim or adjustments made based on per-board cost-effectiveness.
During the build-up, it becomes easier for manufacturers to troubleshoot problems because any divergence in design has been thoroughly documented. Design engineers only need to pinpoint where these occurred and isolate them until the offending changes have been identified and remedied. As copy exact demands that changes to the manufacturing process are made conservatively, the number of variables to test should be minimal.
Your Contract Manufacturer’s Exacting Standards for Quality
The copy exact process is essential to ensure manufacturing continuity when production is spread between multiple facilities. Following these tenets benefits manufacturers and clients. Parties want to know that the quality of their products is independent of wherever they are being produced. By removing the ability for deviations in design, at least in the early stages of production planning, PCBs developed in one facility can seamlessly transfer over to another. Ultimately, it’s peace of mind for both the contractor and the contractee.
Regardless of the manufacturing site, we at VSE are a committed team of engineers inspired to build electronics for our customers. Paired with our professional manufacturing partners, we aim to deliver the highest quality PCBs in numerous life-saving and changing industries.
