Laser processing of quartz for microfluidic device fabrication

This paper presents a fast fabrication process of microfluidic channels with quartz substrates. Microchannels were ablated on the surface of quartz samples with a CO₂ laser. Double sided Pressure Sensitive Adhesive (PSA) was applied to bond the samples with scribed microchannels to flat glass sheets. Dimensions of the fabricated channels were characterised with optical microscopy and laser profilometry. The recorded data was modelled with a BoxBehnken experiment design using Response Surface Methodology. Characterisation included also the measurement of optical transmission through the processed glass and measurement of flow rate through the fabricated channels. With an average width of 165 αm and depth of 280αm, fabricated channels had appropriate dimensions for a range of microfluidic applications. A significant width of the laser processed channels provided 100% transmission for a wide range of the optical spectrum. These fabricated channels were also shown to not significantly retard the fluid flow rate thus making these channels applicable for integration into numerous detection systems for chemical separation applications.