Gao He, Tan Hua, Zhang Wei, Morton Keith, Chou Stephen Y
Nanostructure Laboratory, Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA.
Nano Lett. 2006 Nov;6(11):2438-41. doi: 10.1021/nl0615118.
Imprint pressure uniformity is crucial to the pattern uniformity and yield of nanoimprint lithography (NIL) and, hence, its applications. We studied a novel imprint method, air cushion press (ACP), in which the mold and substrate are pressed against each other by gas pressure rather than solid plates, and compared it with a common method, solid parallel-plate press (SPP). We found that (a) under normal imprinting conditions the measured pressure distribution across a 100-mm-diameter single imprint field in ACP is nearly an order of magnitude more uniform; (b) ACP is immune to any dust and topology variations on the backside of the mold or substrate; (c) when a dust particle is between the mold and substrate, ACP reduces the damage area by orders of magnitude; (d) ACP causes much less mold damage because of significantly less lateral shift between the mold and substrate; and (e) ACP has much smaller thermal mass and therefore significantly faster speed for thermal imprinting.
压印压力均匀性对于纳米压印光刻（NIL）的图案均匀性和产量及其应用至关重要。我们研究了一种新型压印方法——气垫压印（ACP），即模具和基板通过气压而非实心板相互挤压，并将其与一种常用方法——固体平行板压印（SPP）进行了比较。我们发现：（a）在正常压印条件下，在ACP中测量的直径为100毫米的单个压印区域上的压力分布均匀性几乎高出一个数量级；（b）ACP不受模具或基板背面任何灰尘和拓扑变化的影响；（c）当模具和基板之间有灰尘颗粒时，ACP将损伤面积减小了几个数量级；（d）由于模具和基板之间的横向位移明显更小，ACP对模具造成的损坏要小得多；（e）ACP的热质量小得多，因此热压印速度明显更快。
