July 11, 2011 -- Jan Vardaman, president and founder of TechSearch International, summarizes highlights from her SEMICON West presentation on through silicon vias (TSV) (Tuesday, July 12, 2:00-4:30PM, Heterogeneous Integration session). "We're finally moving from PowerPoint engineering to real engineering [with respect to TSVs,]" said Vardaman, though progress is slow and will require patience. Wafer bond/debond and wafer thinning/wafer handling are gaining the most attention, she says. And supply chain logistics responsibilities (foundries vs. outsourced semiconductor assembly and test [OSAT]) need to be worked out. Metrology tools are needed to better investigate processes and reliability and it would be nice to see more data. For more on the topic of metrology, SEMATECH is holding a session on 3D metrology at the Marriott Marquis, San Francisco, July 13, at noon. While Vardaman would like to hear more about reliability, especially at the board level, she doesn’t think people are ready with a lot of data at the moment.
One alternative to TSVs -- package-on-package (PoP) -- is going strong. CAGR for PoP is forecasted to be 31% 2009-2015, driven by tablets and smart phones. PoP enables memories from different suppliers to be interchanged on the standardized top memory package footprint.
With respect to LED packaging, look for improved materials that address thermal environment that impact reliability, particularly for home lighting applications.
Vardaman provides market data on wafer-level packaging (WLP) shipments (Fig. 1), which are being driven by mobile phones. The CAGR for WLP demand is 12.5% between 2009 and 2014. Vardaman reports that as this growth in WLP continues, it drives the use of dielectrics for redistribution layers (RDL). As a result, there is an industry shift from BCB to polyimide or polybenzoxazole (PBO). Other WLP trends are listed below:
Consumer products and other applications:
Mobile phones (highest volume application)
Digital cameras and camcorders
MP3 players (such as iPods)
Portable navigation systems
Laptop and tablet computers
WLPs for many device types:
WLPs for analog functions, power management, RF, wireless LAN, IPD, LED driver, sound IC, etc.
Highest I/O count 309 (Fujitsu power management IC)
Increasing number of 0.4mm pitch parts
Growth in popularity of fan-out WLP (FOWLP):
Shipments of more than 35 million units
Increased number of wireless productions will be using fan-out WLP
Capacity shortage for 300mm WLP:
Regional shortage (Taiwan)
CAPEX for additional capacity of both 200mm and 300mm
Companies adding capacity include TSMC, ASE, and STATS ChipPAC