ISFET pH-Sensor Sensitivity Extraction Using Conventional MOSFET Simulation Tools

P1SM.4 - Ion Sensitive Field Effect Transistor Performance Enhancement with High Bandgap Semiconductors

“…The charge distribution in ISFET consists of the charge in the semiconductor channel, surface charge on the Insulator-Electrolyte interface due to ion adsorbing and charge distribution through the diffuse layer. By solving the charge and potential equations of different regions, ID related of each pH is obtained [4]. Numerical simulation tools are used to solve ISFET charge and potential equations .In this case, the sensor sensitivity is given by [4]:…”

A numerical simulation tool for nanoscale ion‐sensitive field‐effect transistor

“…where Àlog([H + ] b represents the pH of the solution). Two ways can be used to express ISFET sensitivity [2]: the first one uses S 1 defined as the absolute value of change in I D per unit change in pH with V ref fixed, so,…”

“…Ion-Sensitive Field-Effect Transistor (ISFET), which was first developed around 1970 [1], have attracted much attention for pH sensing applications because of its promising advantages compared to traditional methods based on glass electrodes or litmus papers. While glass electrodes are fragile, vulnerable to external stimuli, and difficult to be miniaturized, ISFETs are more resistant to damage, smaller in size, have relatively high sensitivity, and can be used at high temperature [2,3]. Moreover, ISFET can be produced on the top of matured FET technology [4] and feasible for use with micro/nano-systems.…”

“…Research work on ISFET has been made through various approaches including experimental characterization [7,8], modeling [9][10][11][12], and software simulation [2,3,8]. Regarding software simulation approach, it is usually based on using technology computer-aided design (TCAD) software of conventional MOSFETs, then, introducing some modifications to conform to ISFET operation [2,3]. This sometimes requires the work in two different platforms [2], or it alternatively uses lumped parameters for the electrolyte layer [3].…”

“…Regarding software simulation approach, it is usually based on using technology computer-aided design (TCAD) software of conventional MOSFETs, then, introducing some modifications to conform to ISFET operation [2,3]. This sometimes requires the work in two different platforms [2], or it alternatively uses lumped parameters for the electrolyte layer [3]. To the author's knowledge, none of the simulation studies that have been made to investigate ISFET performance uses self-contained simulation tool dedicated for nanoscale ISFETs.…”