Hot embossing was done at 150 ℃ on a COC pellet for 6 min under 1.38 MPa followed by maintaining the polymer for 10 min at 25 ℃ under the same pressure . Also, PC microchannels were prepared via compressing PC plates on a photolithographic patterned silicon mold at 155 ℃ with 1.2 MPa for 2 min followed by 5 min at 50℃ while the pressure was kept constant . Young et al. hot embossed PS substrates against an epoxy mold at 125 ℃ under the 900 kgf pressure for 15 min . COP/COC have shown superior performance compared to PMMA chips fabricated via hot embossing, with higher signal to noise ratios and higher electrophoresis efficiencies due to their low impurity levels and high glass transition temperatures . The embossing reference temperature (143℃) for COC/COP microchannels is determined by the viscoelastic property of these polymers, while other processing parameters such as the temperature, time, and pressure in the cooling and demolding stages are determined by the Taguchi method. A COP microfluidic channel is said to have a high repeatability and low substrate deformation when it exhibits the following optimized parameters: reference temperature 143 °C, holding time 2 min, pressure 1.6 MPa, and demolding temperature 80 °C .