Recent Advances in Enhancing the Sensitivity of Biosensors Based on Field Effect Transistors

Abstract Biosensors based on field effect transistor (FET), also known as Bio‐FETs, offer numerous advantages, including high sensitivity, rapid response speed, low operating voltage, compact size, high reliability, and easily integrative. These features endow Bio‐FETs with tremendous performance in rapid analysis for samples with ultra‐low concentration at large‐scale, broadening their multiple potential applications. In recent years, the research based on Bio‐FETs has attracted more and more attention. A lot of effort is put into the challenge to improve their sensitivity, which can be influenced by various factors. This review focuses on the current approaches from multiple perspectives, including overcoming the influence of Debye shielding effects, promoting the binding efficiency of analytes and FETs surface, and improving the structures of FETs device. Correspondingly, novel strategies to increase the Debye length, facilitate high frequency electric field modulation, enhance the specific interaction efficiency, and enlarge the specific surface area (SBET) are also summarized. Additionally, there is a lack of a reliable standard method to characterize the sensitivity of FETs currently. Regarding this issue, the most commonly used definitions and representation parameters of sensitivity are also evaluated. Overall, this review outlines the potential future research directions to offer insights for enhancing the sensitivity of Bio‐FETs.