High-Sensitivity pH Sensor Based on Coplanar Gate AlGaN/GaN Metal-Oxide-Semiconductor High Electron Mobility Transistor

The sensitivity of conventional ion-sensitive field-effect transistors is limited to the Nernst limit (59.14 mV/pH). In this study, we developed a pH sensor platform based on coplanar gate AlGaN/GaN metal-oxide-semiconductor (MOS) high electron mobility transistor (HEMT) using resistive coupling effect overcome limit. For coupling, comprising control (CG) and sensing (SG) was designed. We investigated amplification with change in magnitude resistance connected series each CG SG via Silvaco TCAD simulations. addition, disposable extended applied as cost-effective that helped prevent damages due direct exposure MOS HEMT chemical solutions. exhibited considerably higher than limit, dependent ratio SG, well excellent reliability stability non-ideal behavior. study expected be readily integrated wide transmission bandwidth, temperature, high-power electronics highly sensitive biosensor platform.