Ph.D. Proposal Presentation by Hong-seok "Moses" Noh
Friday, May 10, 2002

(Dr. Peter Hesketh, advisor)

"Parylene Microcolumn for Miniature Gas Chromatograph"


It has been a dream to have hand-held chemical analytical systems such as miniature gas chromatography (GC). If a rapid, sensitive and selective hand-held GC system is realized, it could be used for the field detection of chemical and biological warfare agents and explosives. The most important and bulky parts of a GC system that need to be miniaturized are a capillary column and temperature controllable convection oven. Up to now, micromachined silicon/glass columns have been used to replace a conventional silica capillary column.

A new miniature GC column containing an embedded heating element is proposed here. Flexible parylene column can be fabricated by parylene coating of micromachined silicon channel and parylene/parylene fusion bonding. The heating element of the parylene column can also be formed by metal deposition. This work will pioneer a new method to form a free-standing parylene structure. The main advantages of a parylene column is its low thermal mass. This will provide faster thermal cycling of the column. In addition, the embedded heating element will maximize the advantage with lower power consumption. The performance of parylene column will be examined by using a conventional GC system and microfabricated components.