Portal de Periódicos da CAPES

High-throughput integration of optoelectronics devices for biochip fluorescent detection

2003; SPIE; Volume: 4982; Linguagem: Inglês

10.1117/12.478145

1996-756X

Evan P. Thrush, Ofer Levi, Ke Wang, James S. Harris, Stephen J Smith,

Innovative Microfluidic and Catalytic Techniques Innovation

Miniaturized, portable and robust sensing systems are required for the development of integrated biological analysis systems and their application to clinical diagnostics. This work uses vertical cavity surface emitting lasers (VCSELs), optical emission filters and PIN photodetectors to realize monolithically integrated, near infrared, fluorescence detection systems. The integration of these micro technologies with biochip applications will drastically reduce cost and allow for parallel sensing architectures, which is particularly useful for flow channel arrays such as in capillary array electrophoresis. This paper focuses on the fabrication of integrated fluorescence sensors. Fabrication procedures have been developed to realize intracavity contacted VCSELs and low noise photodetectors, such as selective AlGaAs wet etching and via planarization. A reflow process with positive photoresist has been developed to provide via electrical contacts and to optically isolate the photodetector from the light source. Three-dimensional microstructures can be simply made by this reflow technique. Optical simulations predict that a detection sensitivity lower than 10000 molecules per 10 4 μm 2 sample area. Single molecule detection may be possible in certain sensing architectures.