In this work we fabricated and characterized nanofluidic lab-on-a-chip devices for the analysis of single DNA molecules using FIB-SEM.
Direct FIB nanopatterning of silicon master stamps allows fast prototyping of nanochannels of different shapes, cross sections and depths. Moreover, the fabrication of 3D structures, such as funnel-shaped inlets to connect the nanochannels to the much deeper and wider microchannels, is straightforward. This is essential to ensure an optimal DNA flow in the fluidic chip. By means of UV nanoimpriting the pattern on the silicon master stamp is transferred to a polymer-on-glass stamp, which is used as a stamp in a second UV nanoimprint step, to create the actual chip.
In the FIB-SEM not only the master stamps can be machined, but the entire fabrication process can be monitored in a non-destructive way. ZEISS unique local charge compensation enables high-resolution SEM characterization of the highly insulating polymer-on-glass stamps and devices without any metal coating allowing us to use the devices after their inspection.