Matching component packaging to product lifecycle demands proves challenging.
Imagine a world in which a certain long-life battery lasts “just long enough.” In this world—where the lifecycle demands of a product are perfectly in sync with a component’s form, fit and function—designers wouldn’t have to choose between a component’s performance or the size of the device.
In the electronics industry, where lifecycles are accelerating, matching a component’s characteristics to a product’s performance requirements is challenging. As products become lighter, smaller and more energy efficient, component manufacturers are developing small, thin, stacked or embedded packages that occupy minimal board space while maximizing the integration of component functions.
Each type of packaging, however, requires a trade-off among interrelated factors including design requirements, economics, manufacturing infrastructure and a product’s useful life. In other words, not every package is right for a product’s application, says Vern Solberg, principal of Solberg Technical Consulting in Madison, Wis.
Reliability and Obsolescence
In addressing lifecycle, some products only need to work once, some require continuous service for years, and others might be replaced due to advancements in function and technology. “The key issue for any of these applications is the component’s physical robustness and reliable operation in the end product’s use environment,” Solberg says.
While performance and reliability are always paramount, other factors affect the fit between component packaging styles and a product’s useful life. One of these is obsolescence, says Ken Stanvick, senior vice president and co-founder of the San Francisco-based consultancy Design Chain Associates. Some packaging styles might be discontinued before a long-lived product—such as a medical instrument—reaches the end of its useful life. “A classic example would be through-hole packaging,” Stanvick says. “Is through-hole still viable when the dominant manufacturing technology is surface mount?”
Another obsolescence issue has intensified with the advent of RoHS. It’s no secret that packages typically using tin and lead, such as traditional ball grid arrays (BGA), are being phased out by component suppliers. Mixing a lead-free BGA with a leaded solder can affect a product’s long-term performance and reliability, Stanvick says.
Variable Short List
Products with shorter lifecycles, like many consumer electronics, present their own challenges. Most of these products are small, lightweight and energy efficient, fueling demand for miniature, leadless, stacked or embedded packaging solutions.
“Although the majority of ICs in use today are small-outline and fine-pitch leaded devices, the majority of new product offerings are furnished without leads,” Solberg says. “Mainly addressing the market for high-volume handsets and other portable electronics, some form of array packaging (BGA, DSBGA, WLBGA) has become the most dominant. Other leadless products have emerged, as well.”
Cost is a key factor in the design and manufacture of short lifecycle products. Leading edge packaging technologies, such as embedded or vertically stacked components, come at a premium price. Consumer electronics are notoriously price sensitive, so designers have to measure the benefits of a smaller footprint against packaging costs and the end product’s useful life.
“It may not make sense to use an embedded component in a throw-away toy just to gain space in the footprint,” Stanvick says.
Assembly Factors
Designers might also face challenges at the assembly level: Some electronics manufacturing services (EMS) providers might not have the right equipment to place tiny, delicate packages on a board. “A designer may select a great package, go to its EMS partner, and be told, ‘We don’t have the ability to place these correctly or this [solution] doesn’t yield very well,’” Stanvick says.
Solberg says costs will come down as these packaging styles are more widely adopted or are replaced by yet-newer technologies. IC packaging will continue to evolve, but it’s hard to predict emerging innovations. “I’m seeing a greater use of uncased die on some of the wireless handset products,” he says. “These are typically very small die with a uniform array ball or bump contact pattern for mounting on conventional circuit boards. These devices are classic examples of WLBGA, where the entire packaging process and testing is performed at the wafer level before singulation [sawing].”
A number of companies are supplying multiple-die packages: stacking die, stacking packages (PoP), and mounting multiple die onto flexible substrates, and folding and bonding segments to create a single-package outline. “The challenge suppliers will need to consider with many of these [often application-specific] multiple die products is to establish a reliable source of supply for the die elements and control cost objectives by accurately anticipating die yields,” Solberg says.
“There are so many IC packaging techniques available to the user today,” he says. “But not all will be appropriate for many applications.”
