A Junctionless-Multigate Design to Improve the Electrical Performances for Deep Submicron ISFET-Based Sensors

In this work, a new multigate pH-ISFET sensor design, called the Junctionless Gate All Around (GAA) ISFET sensor (JGAAISFET), and its numerical analysis have been proposed, investigated and expected to improve the fabrication process and the sensitivity behavior for pH-ISFET sensor-based applications. The numerical analysis has been used to predict and to compare the performances of the proposed design and conventional pH-ISFET, where the comparison of device architectures shows that the proposed pH-JISFET sensor exhibits a superior performance with respect to the conventional pH-ISFET in term of fabrication process and electrical performances. The numerical model provides a basic framework to account for the electronic and chemical performances in future multigate pH-ISFET designs, being easily adaptable to gate structures as the double-gate (DG) or tri-gate (TG). Moreover, the proposed design has linear pH sensitivities of approximately 59.6 mV/pH for wide concentration range (from pH = 2 to pH = 12). The obtained results make the Junctionless ISFET sensor a promising candidate for future integrated CMOS-based sensors.