Dual-gate ion-sensitive field-effect transistors: A review

Abstract

Ion-sensitive field-effect transistors (ISFETs) are electrochemical sensors that work on the principle of metal-oxide field-effect transistors. Dual-gate ion-sensitive field-effect transistors (DGISFETs) are an advanced version of ISFETs with an additional gate dielectric, resulting in sensitivity enhancement on account of the coupling of the capacitances of the two gate dielectrics. ISFETs were demonstrated first in 1970 and there are several review articles available on various aspects of ISFETs; although DGISFETs were first demonstrated in 2010, there are no focused review articles on this subject and this is the motivation of present work. This review has explored the understanding of the basic platform, the working principle, different structures, and various applications of DGISFETs. Further, types of DGISFETs are elaborated based on their architecture, material used for fabrication, and substrates used for such devices with utilization of different semiconductor and gate dielectric materials, rigid and flexible substrates. The state-of-the-art of rigid and flexible DGISFETs is discussed for various applications. Challenges in the fabrication and utilization of DGISFETs in various fields and further advances are discussed.