Super-Nernstian ion sensitive field-effect transistor exploiting charge screening in WSe2/MoS2 heterostructure

Abstract Ion-sensitive field-effect transistors (ISFETs) have gained a lot of attention in recent times as compact, low-cost biosensors with fast response time and label-free detection. Dual gate ISFETs been shown to enhance detection sensitivity beyond the Nernst limit 59 mV pH ?1 when back dielectric is much thicker than top dielectric. However, back-dielectric limits its application for ultrascaled point-of-care devices. In this work, we introduce demonstrate sensor, WSe 2 (top)/MoS (bottom) heterostructure based double gated ISFET. The proposed device capable surpassing uses thin high-k hafnium oxide oxide. 2D atomic layered structure, combined nanometer-thick bottom oxides, offers excellent scalability linear maximum 362 . We also used technology computer-aided (TCAD) simulations elucidate underlying physics, namely electric field screening through channel interface charges due heterointerface. mechanism independent thickness that makes miniaturization these devices easier. super-Nernstian behavior flipped MoS (top)/WSe results open up new pathway engineering an option enhancing ISFET limit, next-generation single-molecular diagnostics.