A method to examine red blood cell (RBC) deformability has been proposed by passing RBCs through a slit-shaped channel that is narrower than the RBCs to observe their velocity changes. However, the deviation of the evaluated values is significant even if the RBCs are deformed in the same way as they observed in microscopic bottom view. There is a possibility that the RBCs may have different shapes when observed from the cross-sectional side of the channel. To verify this possibility, it is necessary to observe from the cross-sectional side of the channel. However, the conventional method of fabricating microchannel molds generates a large number of creases that disturb observation, on the sides of the microchannel. In this study, we propose a new method of fabricating molds while maintaining the fluidity of SU-8 as a way to reduce creases on the sides of PDMS microchannels. Experimental results show that we confirmed that our new method has a less blurred features compared to conventional method.
