TSMC to roll 3D IC assembly service next year

Taiwan Semiconductor Manufacturing Co. Ltd (TSMC) has targeted the beginning of the next as the target date for the roll out of its 3D IC assembly service. This is according to Maria Marced, president of TSMC Europe, who also indicated that the company has one year to get all physical design kits and EDA support in place to allow customers to design with TSMC's chip on wafer on substrate (COWOS).

TSMC is already working with companies on the use of silicon interposer layers to carry multiple die, such as Xilinx. These 'first wave' 3D customers will be able to continue using external packaging partnerships if they choose. However, when the 3D IC assembly service is offered TSMC plans that for most customers the 3D assembly is done by TSMC.

A number of mobile applications processor companies, including Qualcomm and ST-Ericsson, are known to be investigating 3D IC packaging specifically to make use of wide I/O DRAM that is expected to relieve bandwidth issues and reduced energy consumption.

Marced said that the use of multiple die in components—already commonplace in multichip package (MCP) memory for mobile applications—would likely change the nature of IC logic and SoC design. It would allow different functions to be developed on different optimized processes and brought together making use of through silicon vias (TSVs) created in thinned wafers. TSMC is offering a TSV-first approach to 3D IC stacking, noted Marced.

She argued that large amounts of non-volatile memory or wide I/O DRAM could be introduced into application processors without having to include such technologies in leading-edge logic processes. "We believe there is a good way of achieving performance while saving power and real-estate, which is advanced packaging." Developers could stack an embedded flash device in 40nm on an application processor in 28 or 20nm, Marced added.

What remains unclear is whether TSMC is prepared to assemble die from different vendors, such as memory die from specialist manufacturers as part of its 3D IC assembly service. It is also a possibility that this assembly transition could result in TSMC offering some standard die for inclusion in 3D stacks as part of its portfolion of IP. "It could be that the IP goes upstream, but one thing we are very careful of is that we will never compete with our customers. We will remain a pure foundry supplier," stated Marced.

- Peter Clarke
??EE Times