ORGANIC-SILICON INTERFACE
Abstract
A review of the performances of existing field-effect-transistor (FET) based biosensing devices and reports of fundamental studies of FET structures in a planar geometry identify substantial amplification improvements in eliminating metal intermediaries between the biorecognitive surfaces and the silicon channels, reducing thicknesses of insulating gates and selecting channel apertures that are comparable with achievable thicknesses of depletion layers. Exemplary improvements have been achieved in FET-based silicon nano-wires in which biorecognitive surfaces were attached to the oxidized surfaces that functioned as insulating gates. Fundamental studies in which the silicon dioxide gate was replaced with an organic layer using Si–C chemistry demonstrate the retention of the field-effect characteristics and promise improved performance potential to present FET-based devices. These studies also report electrical field compression of the organic layer and electrical polarisation of the electrolyte that have operational implications for biorecognition. Development of practical robust devices that can exhibit unambiguous recognitive capabilities in diverse biological aquatic environments is dependent on further extensive fundamental studies of organic-silicon interfaces and bio-recognitive processes.
Biomimetic Workshop, Department of Industry Science and Technology — IAP Program, Australian Government.
