Locally-gated, suspended silicon nanowire FETs for biomolecular sensing

In this paper, we have fabricated individually-gated suspended nanowire sensors on SOI with subthreshold slope, mobility, and noise characteristics comparable to bulk silicon MOSFETs. Local gate control enables inversion and accumulation mode devices on the same chip, allowing complementary circuits for differential sensing. In addition, local gating will allow individual trimming of each device on a chip to maximize sensitivity. Suspended wires have greater surface area exposed for sensing and may also avoid some of the sensitivity limitations inherent to surface bound nano wires sensors in laminar flow.