Image of the Week - 24 October 2006

Pore Structure of Microfluidic Flow Cell

This image shows the pore structure of a micro-fluidic flow cell designed to evaluate the effect of porous-media structure on mixing in groundwater. A small 100-micron cylinder is surrounded by larger 300-micron cylinders on the periphery. The outer ring was created by using an adhesion promoter between the silicon wafer and the photoresist (PR) during the photolithography stage of fabrication. In this case the PR was only partially developed, leaving a thin coating of PR around each cylinder. After etching with ICP-DRIE, this created the ring structure around the edges of the cylinders.

Image Courtesy: Thomas Willingham, Environmental Engineering

Contact: thomas_willingham@yahoo.com