Development of fluid-based heating and pressing systems for micro hot embossing

This paper reports three innovative methods of rapid heating and uniform pressing for micro hot embossing. Fluids were used as heating and pressing media. With these three systems, the temperature of substrate rises rapidly and uniform pressure is exerted over the whole substrate. The working fluids used in this experiment included steam, gas, and oil. In addition, rapid heating through far infrared radiation (FIR) was also implemented with a gas pressurized hot embossing process. It was found that a 0.2 millimeter-thick PVC substrate can be heated from 25°C to 130°C in 30 seconds using steam heating, in only 25 seconds using FIR heating, and in 3.5 minutes using oil heating. The heating speeds of all three methods are much faster than those using conventional hot-plate heating, which takes more than 10 minutes. Successful replications of micro-features onto substrates have been achieved.