DALSA Semiconductor, a premier supplier of specialized and custom wafer foundry services and a division of DALSA Corporation (TSX:DSA), is pleased to announce successful tests in creating conformal copper seed layers on through-silicon via structures (TSVs) using the eG ViaCoatTM process from Alchimer S.A. (Massy, France), a leader in nanometric metallization. As a result of these successful tests, DALSA intends to license Alchimer's technology to enhance its MEMS production capabilities.
"For years, DALSA Semiconductor has fabricated low cost MEMS products using via-first TSV for its 3D integration technologies," commented Luc Ouellet, VP of Technology Development at DALSA Semiconductor. "With Alchimer's copper-based eG ViaCoat approach we can support consumer MEMS products with faster operating frequencies and higher power density with even lower resistance and higher thermal dissipation through TSV. Alchimer's approach for TSV is a strategic technology allowing us to mass produce MEMS devices in cost-sensitive markets."
Alchimer's eG ViaCoat is an electrochemical coating process for the copper seed metallization of TSVs used in advanced 3D packaging applications. eG ViaCoat enables over 50% reduction in cost of ownership compared to dry vacuum processes. eG ViaCoat won the "Best of the West Award" at Semicon West 2008.
In order to secure the license agreement with DALSA, Alchimer successfully demonstrated the coverage performance of its product on deep reentrant TSVs. A reentrant TSV is one whose diameter is narrower at the surface of the substrate than at the bottom; it is a characteristic shape produced by faster Bosch deep reactive ion etching (DRIE) processes. Since eG ViaCoat is able to demonstrate excellent step coverage on reentrant structures, it allows high etch rate Bosch processes to be used, cutting the costs of DRIE steps by up to 50%. These cost savings in the faster DRIE steps are in addition to the cost savings made in the copper seed metallization step. Alchimer also successfully demonstrated the subsequent void-free copper fill on these deep reentrant TSV structures.
Steve Lerner, CEO of Alchimer, added, "We are very excited to be working with DALSA, who is not only a leader in the MEMS foundry business, but also a company committed to creating innovative technologies and quality products."