Optimization of the Back Enhanced BESOI MOSFET working as a charge-based BioFET sensor

This paper presents for the first time the
^BE
SOI (Back Enhanced SOI) MOSFET working as a charge-based BioFET sensor. The experimental device was used to calibrate the numerical simulations in order to optimize the biosensor improving its sensitivity. The biomaterial is deposited on the silicon dioxide on the underlap regions (between drain/source electrodes to front gate sidewalls) for a large range of charges concentration at the biomaterial/silicon dioxide/silicon film region. It was defined a biosensor sensitivity in order to evaluate its performance when the devices dimensions like the transistor channel (L) and underlap (L
_UD
) lengths, silicon film (t
_Si
), gate oxide (t
_ox
) and buried oxide (t
_BOX
) thicknesses were changed. The optimum charge-based BioFET sensor device based on
^BE
SOI structure was obtained for L=100nm, t
_BOX
=250nm, L
_UD
=1μm, t
_ox
=5nm and t
_Si
=20nm.