Low-Mass PECVD Oxynitride Gas Chromatographic Columns

This paper describes the realization of low-power micro gas chromatography columns for portable gas analysis systems. The columns are fabricated using complimentary metal-oxide-semiconductor-compatible buried-channel plasma- enhanced chemical vapor deposition oxynitride films that have nearly zero stress at room temperature, high deposition rate (~1 mum/min), high etch rate selectivity (~1:80), low thermal conductivity (< 5 W/mdegC), and low thermal stress (< 140 kPa/degC). The buried channel process utilizes these films to form 25-cm-long 65-mum-ID semicircular columns on a 6-mm-square chip. With more than 5000 theoretical plates, these columns separate multicomponent gas mixtures with performance comparable to that of commercial fused silica capillary columns. The columns are capable of multisecond analyses when integrated with low-dead-volume injectors and dissipate less than 10 mW at 150degC in vacuum.