Conductive microfluidic interconnects to enable scalable 3D manufacturing of wearable electronics

This paper investigates the geometry and surface finish of channels machined into polydimethylsiloxane using a continuous wave CO2 laser. In order to investigate the various mechanisms, that could affect the channel geometry, both the laser power and trace speed were varied in conjunction with the use of a fixed focal size to allow comparison between configurations. It was discovered that as the power level increases, repeatability decreases while dimensional variability of the channel along its length and multiple iterations increases. It was found that the power output of the laser has a greater effect on the dimensions of the channels than the total energy input into the material. Varying configurations were used when creating these channels resulting in a strong correlation between both power and speed with regard to depth. However, at higher energy levels this relationship appears to break down and the depth of the cut reduces when compared to similar laser configurations at a lower power level.