Asymmetric fluid-structure dynamics in nanoscale imprint lithography

pressure distribution. Then this pressure must be numerically integrated to obtainthe force and torque.7.2.2 Distributed parameter model of the mechanical systemThe mechanical system has been modeled as a lumped parameter massspring-dampermodel leading to a two degree of freedom mechanical system.Structural interaction leads to an increase in the number of degrees of freedom.For example, the revolute joint adds another rotational degree of freedom that hasnot been modeled in this research. Screw systems theory could be used to modelsuch mechanical systems with a large number of degrees of freedom.7.2.3 Measurements with Patterned TemplatesThe current gap-sensing scheme can be used to measure the gap betweenthe template and substrate for base layers down to 350 nm without using theIMMA algorithm. This algorithm has not been successfully applied to thecomputation of thin base layers. A workaround to this problem is to have a stepin the template. For the area that is not used for imprinting, there can be a 300 nmrecess in the template, for example. This is illustrated in Figure 7.4.Measurements using patterned templates can then be performed withoutexceeding the limits of the gap sensing tool.Recess DepthFigure 7.1 Recessed depth to aide in gap sensing with pattern templates101