Planar thin film device for capillary electrophoresis

Abstract

Hollow tubular microfluidic channels were fabricated on quartz substrates using sacrificial layer, planar micromachining processes. The channels were created using a bottom-up fabrication technique, namely patterning a photoresist/aluminum sacrificial layer and depositing SiO(2) over the substrate. The photoresist/aluminum layer was removed by etching first with HCl/HNO(3), followed by etching in Nano-Strip, a more stable form of piranha (H(2)SO(4)/H(2)O(2)) stripper. Rapid separation of fluorescently labeled amino acids was performed on a device made with these channels. The fabrication process presented here provides unique control over channel composition and geometry. Future work should allow the fabrication of highly complex and precise devices with integrated analytical capabilities essential for the development of micro-total analysis systems.

Electroosmotic flow in vapor deposited silicon dioxide and nitride microchannels

“…This is followed by thermal evaporation of a 300 nm aluminum film. AZ 3330 photoresist is then spin-coated to a thickness of 3 m. The photoresist layer is patterned to define the microchannel cores, [16][17][18][19] which are then reflowed on a hot plate that is ramped from 90°C to 300°C. This gives the channel cores a rounded shape.…”

“…Fabrication of a thin film microchannel [17][18][19] begins with a silicon or glass substrate. If a silicon wafer is used, it is necessary to first deposit a layer of thermal oxide that is approximately 3 m thick to prevent electrical breakdown in the substrate.…”

“…Microfluidic channels based on the plasma-enhanced chemical vapor deposition ͑PECVD͒ of these films on planar substrates have recently been generated. [16][17][18][19][20] PECVD is used because it allows for the formation of these films at relatively low temperatures. A large variety of materials can be coated with PECVD oxide or nitride and then be chemically removed, resulting in hollow channels.…”

Optofluidic waveguides: II. Fabrication and structures

“…Examples of microfluidic elements that have been fabricated this way included a capillary electrophoresis separation device (Peeni et al 2005(Peeni et al , 2006. The critical element of the device, two offset T junctions, is shown in Fig.…”

Monolithic integration of fine cylindrical glass microcapillaries on silicon for electrophoretic separation of biomolecules

“…Otherwise, a 100-fold dilution would have been recommended for the prepared sample as prescribed in the previous protocols. 4,38,39 Such high sample concentration might have caused electrodispersion, the band broadening under non-uniform field distribution due to mismatched conductivities between the sample zone and the background buffer. Despite the possible occurrence of electrodispersion, the theoretical plate numbers obtained for the peaks here (Table II) are comparable to those reported in the literature.…”