Surface Preparation as a Step in the Fabrication of Biosensors Based on Silicon Nanowire Field-Effect Transistors: Review

Issues concerning the detection of biomolecular targets by biosensors based on silicon nanowire field-effect transistors are discussed. We list and discuss steps in the surface preparation of silicon nanowires that lead to the efficient, highly sensitive, and selective detection of various analytes. The procedures for cleaning and activation of the surface of the silicon nanowires are addressed. Wet and dry methods for surface cleaning as well as surface-modification strategies applicable to transducers of biosensors are described. Surface modification by silane derivatives (i.e., silanization) and linker attachment is paid particular attention. The causes underlying the undesirable screening effect affecting a nanowire surface upon analyte detection in solutions are provided. The key requirements and strategies relevant to different steps in the preparation of biosensor surfaces that lead to improvement in their performance are mentioned.