You’d think a complete new technology for patterning silicon would merit a long, involved story. And yet it’s just not that complicated. (Easy for me to say…) One of the up-and-coming lithography processes under development is called “nanoimprint lithography” (NIL). It might be hard to imagine that this would work, but, just like it sounds, it involves taking a master “stamp” and impressing it into a liquid resist.
You then harden the resist with some exposure to UV light and release the master. The pattern on the wafer can then direct further more standard processing.
The crazy thing about this is that nanometer-scale features can print. You’d think that the liquid might have trouble conforming to such miniscule hollows in the template. And some of the issues you might think could arise – like parts of the pattern slumping or collapsing after the template is removed – truly are issues that are being studied and addressed.
Right now, researchers are working in the 26-nm realm (according to presentations at SPIE Litho), but they are trying to use the same process as HGST used for their hard drive project – creating working templates from a master template. Quality is still a challenge for those working templates, making this most suitable for applications having large-scale repeated features for which redundancy can be provided for repair.
The presenter from Dai Nippon Printing said that full production is targeted for two years out. We’ll continue to track it… If you get the SPIE Litho proceedings, you can find more in paper 8680-2.