Abstract:
The use of high-aspect ratio silicon nanostructures as a sensor for detection of various analytes was
investigated in the present study. Si nanostructure is a promising candidate due to ease of fabrication, large
surface area, various accessible sizes and morphologies, controllable surface modification and its
compatibility with conventional silicon processing technology. The optical or electrical properties of Si
nanostructures are key sensing parameters that have been used in many chemical and biological sensing
applications. Upgraded metallurgical grade wafers were used for the fabrication of nanostructures by
metal assisted chemical etching (MACE). A detailed analysis of the optical properties is done by UV-Vis
Diffused reflectance spectroscopy, Raman spectroscopy and photoluminance spectroscopy. Morphological
properties, investigated by SEM, provides an insight into the physics of their formation. The adsorption of
chemical or biological molecules into the pores modifies the electrical and optical properties, allowing
convenient and sensitive measurement approach. The high aspect ratio of such nanoporous structures in
chemical and bio sensing applications is addressed in the context of surface chemistry effects and
nanostructures, measuring approaches and sensitivity and stability.
