I have to admit that this year at IMAPS Device Packaging Conference, I spent more time attending technical sessions and less time with the exhibitors than I usually do at an industry event. However, I did manage to check in with a few of them to see what their latest contributions are to the 3D IC and 3D Packaging realm.
I wasn’t surprised to run into Bradley Benton at the Palomar booth – I pretty much expect to see him at these events. In fact, he gave me my first comprehensive lesson in the history of wire bond technologies. I was, however, surprised to learn that the company, which is firmly established in the wire bond business, is venturing into the TSV space with its 6500 Eutectic Die Attach System. Benton says the tool is designed to perform die to wafer processes, and achieves 1.5 µm placement accuracies.
“We recognize that TSV is coming,” he noted. “We have some TSV capabilities now. We’re looking into ways of enhancing that.” Benton says his interest in 3D packaging is why he got into this business 26 years ago. “I always assumed microelectronics would build up and not out.” He said. “What’s new is that we’re finally going at it and doing it with silicon.
I caught up with Kathy Cook of SUSS MicroTec at the tail end of the poster sessions on Thursday, where she was presenting a poster based on Margarete Zoberbier’s recent presentation at SEMICON Korea about some of SUSS’ equipment technologies for TSVs. Cook explained that polymers adhesives may be necessary for permanent bonding when copper alone isn’t enough to hold the wafers together. The take-away message was the company’s achievement of submicron post bond alignment accuracy (.35µm) for permanent bonding and several other new capabilities involving SUSS’s latest 300mm tools – ACS300 Gen 2 Coater and the MA300 mask aligner. The 300mm permanent bonder is the XBC300. SUSS has recently achieved some excellent results in the area of thin wafer handling as well.
Martijn Pierik, of Impress PR, introduced me to the folks at Tango Systems, who were showcasing the company’s flagship PVD system, the Axcela. Ravi Mullapudi, president and CEO, explained how the tool was suited to perform barrier and seed layer processes for TSV, which have been identified as areas still to be addressed from a cost of ownership perspective. He said this dry, vacuum process uses rotating targets in the chamber to perform both steps in one process. The tool can accommodate 150, 200 and 300mm wafers, with quick changover.
Surface Technology Systems
In between catching up on non-industry related news, my good friend Michelle Bourke of STS, clued me in on the companies continued work with improved control of TSV profiles. STS has made lots of progress in maintaining the delicate balance between high etch rates and excellent across-wafer etch depth uniformity. One exciting bit of news she shared with me was the company’s recent R& D success with high speed deep reactive ion etch (DRIE) at 106µm/min. While the process needs to be refined, the point is, they’ve achieved it. So expect to see more on this as the process is tweaked. – F.v.T