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Imprint lithography has been shown to be an effective technique for replication of nano-scale features. Jet and Flash
Imprint Lithography* (J-FIL*) involves the field-by-field deposition and exposure of a low viscosity resist deposited by
jetting technology onto the substrate. The patterned mask is lowered into the fluid which then quickly flows into the
relief patterns in the mask by capillary action. Following this filling step, the resist is crosslinked under UV radiation,
and then the mask is removed, leaving a patterned resist on the substrate.
There are many criteria that determine whether a particular technology is ready for wafer manufacturing. For
imprint lithography, recent attention has been given to the areas of overlay, throughput, defectivity, and mask replication.
This paper reviews progress in these critical areas. Recent demonstrations have proven that mix and match overlay of
less than 5nm can achieved. Further reductions require a higher order correction system. Modeling and experimental
data are presented which provide a path towards reducing the overlay errors to less than 3nm. Throughput is mainly
impacted by the fill time of the relief images on the mask. Improvement in resist materials provides a solution that
allows 15 wafers per hour per station, or a tool throughput of 60 wafers per hour. Defectivity and mask life play a
significant role relative to meeting the cost of ownership (CoO) requirements in the production of semiconductor devices.
Hard particles on a wafer or mask create the possibility of inducing a permanent defect on the mask that can impact
device yield and mask life. By using material methods to reduce particle shedding and by introducing an air curtain
system, the lifetime of both the master mask and the replica mask can be extended. In this work, we report results that
demonstrate a path towards achieving mask lifetimes of better than 1000 wafers.
Finally, on the mask side, a new replication tool, the FPA-1100NR2 is introduced. Mask replication is required for
nanoimprint lithography (NIL), and criteria that are crucial to the success of a replication platform include both particle
control and IP accuracy. In particular, by improving the specifications on the mask chuck, residual errors of only 1nm
can be realized.
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