Abstract by Henry Davis
Physics and Astronomy
Fabrication of a Thermal Gradient Micro-column Gas Chromatograph
The ability to analyze complex mixtures of gas makes gas chromatography (GC) systems the gold standard for volatile analysis. However, current commercial GC systems are large, relegating their use primarily to the lab. Micro GC systems have been made but these short column systems have not yet reached the high performance of laboratory systems. Recent work shows that applying a thermal gradient across a GC system may overcome limitations of a short column. Using plasma etching of silicon we are creating a micro GC chip which will have a 20 cm long channel with a thermal gradient along it. During etching a masking material is required to protect the unetched regions of the silicon. The intense long plasma etch requires a resilient etch mask and we found that a thick, crosslinked polymer stands up the process but created another challenge. After etching, the chemically resistant polymer mask needs to be removed, leaving a clean wafer surface. We tested various removal methods and found that an N-Methyl-2-Pyrrolidone bath, successfully removes the polymer.