Process-simulation systems for ultraviolet (UV) nanoimprint lithography are newly proposed to investigate process physics and resist profiles. The system consists of four modules, which simulate fluid dynamics in the resist-filling process into a pattern, the optical-intensity distribution in the UV exposure process, the mechanical properties in UV curing, and the resist profiles by UV shrinkage. Each module is independent, but shares physical parameters and resist profiles. Simulations on resist profiles by the UV curing process are demonstrated, taking the optical-intensity distribution into account. Also, a database model is newly introduced to simulate the resist profile due to shrinkage by UV curing.

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A new method for the measurement of rheological properties (complex viscosity, viscosity and elasticity) of thin polymeric films is presented. The probe, which is placed on the end of an arm of a mini tuning fork, is caused to oscillate and then is put into poly(methyl methacrylate) films, whose thickness ranges from 30 nm to 1080 nm. All measured properties depend on temperature, thickness of the films, indentation depth and the molecular weight of PMMA. Complex viscosity, viscosity and elasticity are found to be lower at higher temperatures and higher with greater molecular weight. They are also lower for thicker films. The results gained from this experiment may be useful in the development of nanoimprint lithography and many other branches of nanotechnology. Furthermore, the method allows for the measurement of the rheological properties of many different thin films (nanoimprint polymers, oils, lubricants) at different temperatures.