Lithography-Free Technology for the Preparation of Digital Microfluidic (DMF) Lab-Chips with Droplet Actuation by Optoelectrowetting (OEW)

Figure 2

Cross-sectional view (not to scale) of layer sequence of DMF chip. Typical materials and layer thicknesses from bottom to top: 1.0 mm thick glass slide (substrate), (100 ± 30) nm thick ITO electrode layer, (780 ± 10) nm thick a-Si : H photoconductive layer, (360 ± 10) nm thick Parylene C dielectric layer, approx. 10 nm thin hydrophobic PTFE AF 1600 film, from 50 μm up to 250 μm thick spacer stripe or 100 μm thick insulating tape, approx. 10 nm thick hydrophobic PTFE AF 1600 film again, (100 ± 30) nm thick ITO electrode layer, and 1.0 mm thick glass slide (superstrate).