Impact-ionization field-effect-transistor based biosensors for ultra-sensitive detection of biomolecules

摘要

The phenomenon of impact-ionization is proposed to be leveraged for a novel biosensor design scheme for highly efficient electrical detection of biological species. Apart from self-consistent numerical simulations, an analytical formalism is also presented to provide physical insight into the working mechanism and performance of the proposed sensor. It is shown that using the impact-ionization field-effect-transistor (IFET) based biosensor, it is possible to obtain an increase in sensitivity of around 4 orders of magnitude at low biomolecule concentration and around 6 orders of magnitude at high biomolecule concentration compared to that in conventional FET (CFET) biosensors. Moreover, IFET biosensors can lead to significant reduction (around 2 orders of magnitude) in response time compared to CFET biosensors.