July 18, 2011 — During SEMICON West 2011, SEMATECH announced the world’s first 450mm imprinted wafer, accomplished by EV Group (EVG). In a podcast interview, Markus Wimplinger, corporate technology development and IP director at EVG, described the timeline for the 450mm effort and how the company decided to make a strategic move — one that was not so much based on getting a check for the right amount.
|Figure 1. 450mm wafer loaded on the EVG770
The company used its SMS-NIL technology, also known as soft molecular scale nanoimprint lithography, to imprint the wafer. "It was beneficial because it’s very compliant and could also accommodate the limited wafer quality available at 450mm at that point in time," said Wimplinger. "We imprinted 35nm lines and spaces, but this is not the limit that this technology can do. We’ve demonstrated capability down to 12.5nm lines and spaces on smaller substrates."
For the company, the effort was a strategic business decision. "We had a 450mm program for quite some time," said Wimplinger. "So when we designed our second generation stepper, the primary focus was on 300mm, but we had already designed some 450mm capability, so we had the system available: we had the platform that could do it. We believe the transition to 450mm will happen in the not too distant future; it was a strategic decision." EVG introduced a wafer bonding system for 450mm at SEMICON West 2011.
|Figure 2. 450mm step and repeat imprinted wafer with 35nm features.|
Although Wimplinger explained that the timeline for 450mm insertion differs for different players, EVG thinks that the time frame for HVM is 2015-2017. And while nanoimprint is a back-up plan if EUV lithography is not ready, the industry can probably squeeze one more node out of immersion lithography, said Wimplinger.
|Figure 3. Metrology of imprinted features.|