This paper reports a fabrication method of high aspect ratio (HAR) carbon microneedle arrays with controlled geometry and a creation of a superhydrophobic surface utilizing HMDS (hexamethyldisilazane)-modified carbon microneedles. Carbon microneedles ...
This paper reports a fabrication method of high aspect ratio (HAR) carbon microneedle arrays with controlled geometry and a creation of a superhydrophobic surface utilizing HMDS (hexamethyldisilazane)-modified carbon microneedles. Carbon microneedles are obtained through lithography and thermal treatment, which have aspect ratios greater than ten and nanoscale tips by volume shrinkage during pyrolysis of the fabricated SU-8 microneedles. We also stuied the wetting property of carbon microneedle arrays with different base diameters and spacing between needles and created an extremely water-repellent surface using HMDS-treated carbon microneedles. The proposed surface will be of great interest in self-cleaning, low-drag microfluidics, and lab-on-a-chip.