FAN Xiqiu
School of Electromechanical
Engineering,
Zhejiang Ocean University,
Zhoushan 316000, China
 
School of Mechanical Science
and Engineering,
Huazhong University of Science
and Technology,
Wuhan 430074, China

ZHANG Honghai

WANG Xuefang

HU Xiaofeng

JIA Ke

LIU Sheng
School of Mechanical Science
and Engineering,
Huazhong University of Science
 and Technology,
Wuhan 430074, China

Abstract: Nanoimprint lithography (NIL) is recognized as one of the most promising candidates for the next generation lithography (NGL) to obtain sub-100 nm patterns because of its simplicity, high-throughput and low-cost. While substantial effort has been expending on NIL for producing smaller and smaller feature sizes, considerably less effort has been devoted to the equally important issue—alignment between template and substrate. A homemade prototype nanoimprint lithography tool with a high precision automatic alignment system based on Moiré signals is presented. Coarse and fine pitch gratings are adopted to produce Moiré signals to control macro and micro actuators and enable the substrate to move towards the desired position automatically. Linear motors with 300 mm travel range and 1 μm step resolution are used as macro actuators, and piezoelectric translators with 50 μm travel range and 1 nm step resolution are used as micro actuators. In addition, the prototype provides one translation (z displacement) and two tilting motion(a and b ) to automatically bring uniform intact contact between the template and substrate surfaces by using a flexure stage. As a result, 10 μm coarse alignment accuracy and 20 nm fine alignment accuracy can be achieved. Finally, some results of nanostructures and micro devices such as nanoscale trenches and holes, gratings and microlens array fabricated using the prototype tool are presented, and hot embossing lithography, one typical NIL technology, are depicted by taking nanoscale gratings fabrication as an example.

Key words: Nanoimprint lithography Alignment Moiré signals