12 Questions for Occam before buying the farm

The Occam electronics circuit assembly process (Occam Process) was announced amid much fanfare August 1, 2007. Reviews of the Occam ‘process' and predictions of its marvelous benefits to the electronics industry were breathtaking. The process was developed by Joe Fjelstad, president and founder of Verdant Electronics and, upon reading Company press releases, one felt they would be ‘left behind' if they did not get on board the Occam train soon. The process is named after William of Occam, 14th century medieval scholar, author of "Occam's Razor", which in modern language, asserts that when considering a phenomena - the simplest explanation is likely the best. The Verdant folks chose this name for their process because they claim the Occam Process is extremely simple. The Occam effort is also blessed by an impressive list of advisors, which adds credibility to Verdant's claims for Occam. The purpose of this article is to provide additional questions for those considering pursuing the implementation of the Occam Process. I strongly recommend anyone planning on implementing the Occam Process to find answers to most or all of these questions. (More analysis of the process is available on my blog) The Occam Process begins by placing components on a thin substrate, presumably with some sort of adhesive to hold the components. An overcoating of an encapsulant is then deposited on the components. The encapsulant is then cured. The substrate is subsequently inverted and holes are laser-drilled or etched to expose the component leads. Photolithography and copper plating processes then form the interconnections. The process does not require soldering. (Visit the Verdant Electronics Website for a more detailed explanation). Verdant Electronics claims the major requirements the Occam Process addresses are:

"1. The regulatory imperatives (e.g., RoHS) to produce lead-free electronics requires (sic) subjecting them (e.g., the components) to very high temperatures associated with lead-free solder, and involves reliability risks associated with the extensive use of tin plating as a termination finish. 2. The relentless drive to reduce size and cost results in increasing challenges for reliable component placement and attachment. 3. Global sourcing and supply-chain expansion means more distant PCB suppliers, reducing the resources and support for domestic technology development."

Admittedly, these three points have validity. However, all of the above points can and are being addressed with current technology. Are there challenges with current technology addressing these issues? Absolutely, there always will be. There will be many challenges with Occam, too, as well as a few new unknowns. Well, on to the questions for Occam Question 1: The Occam Process involves component placement; encapsulant laminating, etching of holes, photolithography for circuit definition, additive copper plating, and photoresist stripping and cleaning for each circuit layer. How is it a simple process? What is the process, in detail, for a moderately complex product? Question 2: Printed wire board (PWB) assembly and, the PWB itself, each represent only about five (5) percent of the cost of an electronics product. So for my $100 cellular phone, about $5 of the cost is for PWB assembly and $5 for the PWB itself. How does the Occam process reduce this cost? May we see a detailed cost estimate? Question 3: Since the Occam Process involves both PWB assembly and PWB manufacturing processes, who will the early adopters be? How are these adopters expected to modify their facilities, inexpensively, to adopt the Occam process? Question 4: In the Occam Webinar presented to industry September 11, 2007, the Webinar questioned the need for rework - implying the Occam process will be so reliable there will be no need for rework. Isn't most rework performed today a result of the need to repair, or replace, faulty electronics components? If this situation is not the case, what is the data to support Occam's no rework required position? Meanwhile, if it is determined rework is required, what is the Occam rework plan? Question 5: The thermal coefficient of expansion (TCE) of most encapsulant materials is approximately 55x10^-6/^oC (e.g., epoxy), while current PWB laminate (epoxy strengthened with fiberglass) has a TCE of approximately 36x10^-6/^oC which is closer to copper's TCE of 17x10^-6/^oC. In larger Occam-based products, won't the greater TCE of the encapsulant material fracture the copper circuit lines in the normal thermal fluctuations of turning the electronics off and on? Question 6: High-frequency PWBs used in modern laptop computers require exacting electrical impedance design to achieve acceptable electrical performance. This demand necessitates precise thickness and dielectric constant control in the PWB design and in manufacturing. How will the Occam process duplicate this control? Won't the production line assembler need a cadre of electrical design engineers to develop the Occam design for such products? Question 7: PWB stiffness integrity is needed for many applications, such as inserting a card onto a mother board. The PWB owes much of its stiffness to the fiberglass in the epoxy laminate. The Occam Process uses only an encapsulant material (i.e., no fiberglass). How will the stiffness of the encapsulant material compare to an epoxy-fiberglass laminate? Will the stiffness of Occam products be adequate for all or, most applications? What data support the conclusion? Question 8: The Occam Process is touted to be environmentally compliant or, friendly. However, the process uses photolithography and copper plating procedures. Aren't these processes quite ‘dirty'? Won't these processes, which will be new to most potential adopters, be a challenge to implement? Question 9: Total product cost is closely related to product cycle time on the PWB production assembly line, with a typical ‘pulse rate' of 20 to 60 seconds using today's assembly process. The Occam Process uses additive copper plating, which typically requires ten (10) hours to plate 1 mil (0.025 mm) thickness of copper. How can the Occam Process achieve a 20 to 60 second ‘pulse rate' and be competitive with today's PWB assembly rates? Question 10: I am interested in buying an Occam ‘Turn Key' solution. After attending the Occam Webinar, it appears that Verdant expects the user to develop the process. Just what do I get if I license the Occam process? Question 11: The Occam Process is claimed to have superior reliability. What data support this claim? Question 12: Environment recycling is a foundation for the future of electronics. An important part of recycling is disassembly of the printed circuit board (PCB) and the reuse of functional components and hardware in low cost products. This re-use not only saves money, but also protects the environment by obviating the need to produce new components and hardware. Meanwhile, the Occam Process buries the components in encapsulant and ‘welds' the component leads to copper. How can the products manufactured with the Occam process be easily recyclable? The Occam Process is a clever idea developed by some experienced industry leaders. However, many questions are still unanswered. Make sure you get the answers you need before implementation. What is your take on Occam?