Research On Preparation, Surface Treatment Of Porous Silicon And Optics Biosensor

Various optical detecting applications based on porous silicon (PS) haveattracted a great attention due to its remarkable optical properties and large functionalsurface area. PS, with its particular surface morphology, makes this material verysuitable for many different applications in various fields.In this study, N-type (100) PS(resistivity 0.01-0.02Ω·cm)suitable for opticaldetection of immunoreactions was fabricated by double-cell electrochemical etchingmethod under lighting condition method under lighting condition. The effect of light,HF concentration, current density and temperature formation of n-PS, structuremorphology on performance were studied by scanning electron microscopy (SEM)systematically. The results showed that the formation, structure, morphology of PSwere controllable, and PS with homogenous pore, size distribution under comfortableconditions.The fresh PS surface is usually covered by a layer small pore PS which hasbecome an obstruction to biosensor. A series of techniques were adopted in this thesisto improve the surface of PS, and the morphology of PS is significantly improved.A novel immunosensor based on PS for antigen detection was also reported in thispaper. The antigen and the specificity of the antibodies are employed as the target andthe probe in our laboratory, respectively. The immunosensor structure was preparedusing bioconjungation. The results demonstrate the successful detection ofbiomolecule .Controlled experiments were also presented with non-immune antibodyand the results show that this immunosensor possesses high specificity. As ameasurement system, this design is simple, rapid, sensitive and label-free. Theadvantages of this PS immunosensor will be applied to practices in many fields.