Packaging Innovations Stays Focused on Flip-Chip

By Jeff Dorsch

It’s no secret that mobile devices are having a tremendous impact on the electronics and semiconductor industries. What’s less known is the impact mobile electronics is having on IC packaging, driving packaging materials manufacturers and packaging contractors to produce denser, smaller packages to fit into ever-shrinking form factors.

The inexorable drive to fit more functions on one chip, to add more chips to one package and to find cost-effective ways to package and test these chips goes on. Packaging, as a result, is taking on many more forms and types, and some packaging is shifting to the wafer level, according to industry observers and participants.

Risto Puhakka, VLSIresearchRisto Puhakka, president of market research firm VLSIresearch, says that flip-chip technology, previously confined to specialty applications, is gaining wider acceptance. “These parts of the business are going gangbusters,” he notes. “That is driven by the mobile [segment].” Packaging and test contractors are “doing well,” he adds.

Paul Lindner, executive technology director of EV Group, a supplier of bonding, lithography and nanoimprinting equipment, says the industry volumes of flip-chip packages are increasing while their costs come down. Flip-chip technology has matured, he notes, and “the trend is for smaller form factors in mobile devices,” he adds.

The wider adoption of flip chip “was predicted years ago, but every new technology takes time to develop,” Lindner says.

Also seeing “higher demand” is a newer technology, wafer-level fan-out packages, he notes.

Dan Tracy, senior director of SEMI Industry Research and Statistics, last year noted that packaging materials revenue, as a proportion of the semiconductor industry’s global revenue, has increased from about 5 percent in 2001 to an estimated 8 percent for 2012. “In the 2000s, we have seen the introduction of new form factors and configurations like stacked-die, package-on-package, wafer-level, and several other packaging types, and many of these packages require new materials and advanced substrates, thus the increase in the percentage of packaging materials revenues to semiconductor revenues,” he said.

Purveyors of semiconductor test and yield management equipment have their own perspectives on packaging innovation.

Wafer-level chip-scale packages are presenting one challenge, according to Steve Wigley, vice president of marketing for LTX-Credence. With that technology, “final test is no longer available,” he says. Companies must be satisfied with the testing proved by wafer probers, he notes.

The advent of 3DICs, while “pure memory now,” also presents a testing challenge, Wigley says. The question, he says, becomes: “How do we test this cost-effectively?” The LTX-Credence executive adds that there are “all sorts of initiatives for test standards. There’s lots of discussion, lots of debate.”

Brian Trafas, KLA-TencorBrian Trafas, chief marketing officer of KLA-Tencor, says the mobility market demands “much smaller packaging, thinner.” He adds, “These parts are driving demand.” Checking chips while they’re still on wafers is on the rise, he notes.

For KLA-Tencor and other back-end equipment companies, “being able to switch between packaging types” is highly important, Trafas says. “The flexibility is really key for the back end,” along with “high reliability,” he adds.

KLA-Tencor got deeper into the back-end equipment market with its 2008 acquisition of ICOS Vision Systems, a supplier of packaging and interconnect inspection systems, Trafas notes.

SEMICON West will have five events devoted to packaging technology, with two of them on the opening day of the show – Tuesday, July 9. At 10:30 a.m. that day, TechXPOT North in the North Hall of the Moscone Center will host “Generation Mobile: Enabled by IC Packaging Technologies.” The program will feature speakers from Advanced Semiconductor Engineering, Amkor Technology, ASE (US), Semiconductor TechInsights, SK Hynix, and Universal Scientific Industrial.

The program summary says, “Mobile electronics, with a huge spotlight on the thriving smartphone and tablet market, are fueling growth in semiconductors today, a trend expected to escalate over the years ahead. ‘Generation Mobile’ relates to consumers worldwide who now rely on such products as a way of life. As demand intensifies for higher performance, greater functionality, and lower power consumption, our industry is experiencing a strong wave of innovation, inspired by those willing to push boundaries and make these increasingly sophisticated products a reality. IC packaging has firmly established itself as a crucial part of the IC and system design process. In that vein, session speakers will discuss today’s IC packaging solutions, as well as, explore possibilities for future packaging technologies being poised to enable ‘generation mobile’ to flourish and infiltrate lifestyles around the globe.”

At 1:30 p.m. on Tuesday, July 9, the IEEE and its Components, Packaging and Manufacturing Technology Society will present a workshop at the San Francisco Marriott Marquis. The program summary for “THIN IS IN: Thin Chip & Packaging Technologies as Enablers for Innovations in the Mobility Era” reads, “Electronic products, such as smartphones, tablets and other consumer products, drive the overall trend of maximum functional integration in the smallest and thinnest package with lowest packaging costs. One of the key technologies to achieve these goals is thin 3D-packaging. Developments have lately been made with various embedding technologies, such as Fan out WLP and embedded devices. Higher integration levels and lower profiles are also achieved with wafer-level processes, at which most R&D is concentrated in the commercialization of 2.5D ICs (with silicon interposers) & 3D ICs, as well as coreless substrate. Furthermore, there is tremendous pressure to decrease overall package height even with the additional dies stacking through innovation in wafer thinning, TSV, and ultrathin interconnects.”

On Thursday, July 11, at 10:30 a.m., the Advanced Packaging Committee of SEMI Americas will host “MEMS and Sensor Packaging for the Internet of Things” at TechXPOT North.

Smaller, thinner – these are the leading terms in packaging innovation these days. Cost and reliability must be part of the packaging vocabulary as well.