Nanoscale negative-tone quantized patterning by novel selective electrochemical etching of a nanoimprinted sub-200 nm bimetallic tile array.
Quantum lithography (QL) is a revolutionary approach to significantly increase the throughput and lower the cost of electron beam lithography in writing large-area masks with nanoscale features. A major challenge in QL is that its principle can be readily applied to positive- but not negative-tone QL. In fact, negative-tone QL, which is as indispensable as positive-tone QL in practical usage, has not been achieved. Here we propose a new method to overcome the obstacle, and report the first experimental demonstration of negative-tone QL. The new method uses a new type of nanoimprinted blank with the nanoscale tiles made of an aluminum/chromium bi-layer of metals, and a novel electrochemical process that removes only non-tagged quantized tiles of the new blank while keeping tagged ones. The demonstrated negative-tone QL has a 200 nm pitch and 30 nm gap and can be further scaled down to even smaller pitch sizes.
NanoStructures Laboratory, Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA.
Wen-Di
WD
Li
Xiaogan
X
Liang
Stephen Y
SY
Chou