Design of an aerostatic imprint head with off-plane alignment functionality for nanoimprint lithography

Ultra-precision off-plane alignment between the template and the substrate is of great importance to guarantee the quality of patterns manufactured by nanoimprint lithography technology. In this paper, an aerostatic imprint head with off-plane alignment functionality for nanoimprint lithography is developed. The high light of the mechanical design is that the imprint force is transmitted by a spherical aerostatic bearing to the high stiffness frame, thus, bypassing the compliant mechanism, which is employed for high precision off-plane adjustments. This makes the developed device suitable for high load applications while maintaining high alignment precision. The load capacity and stiffness of the imprint device, which are mostly determined by the aerostatic bearing, are studied based on theoretical analysis and experiments. To further increase the stiffness of the device, adjustable magnetic preload is employed. An experiment is performed to study the mechanical characteristics of the imprint head incorporating the magnetic preload structure.