The FET pH sensor model is a surface potential compact model for FET based pH sensors that accurately describes the physics of electrolyte and surface charges that respond to pH. Used with any FET model it characterizes the operation of the device with changes in pH.

• FET pH sensor Model 1.0.1 Verilog-A(ZIP | 4 KB)
• FET pH sensor Model 1.0.1 HSPICE Netlists(ZIP | 360 KB)
• FET pH sensor Model 1.0.1 Parameter Extractor in MATLAB(ZIP | 6 KB)
• FET pH Sensor Model 1.0.1 Experimental Data(ZIP | 7 KB)
• FET pH Sensor Model 1.0.1 Manual(PDF | 952 KB)
• Performance Analysis(ZIP | 55 KB)
• Utility Files(ZIP | 1 KB)
• License terms

[1] R. E. G. van Hal, J. C. T. Eijkel, and P. Bergveld, “A general model to describe the electrostatic potential at electrolyte oxide interfaces,” Adv. Colloid Interface Sci., vol. 69, no. 1–3, pp. 31–62, 1996.

[2] J. Go, P. R. Nair, and M. A. Alam, “Theory of signal and noise in double-gated nanoscale electronic pH sensors.,” J. Appl. Phys., vol. 112, no. 3, pp. 34516, 2012.

[3] R. E. G. Van Hal, J. C. T. Eijkel, and P. Bergveld, “A novel description of ISFET sensitivity with the buffer capacity and double-layer capacitance as key parameters,” Sensors And Actuators, vol. 25, pp. 201–205, 1995.

[4] P. Dak, P. Nair, J. Go, and M. A. Alam, “Extended-Gate Biosensors Achieve Fluid Stability with no loss in Charge Sensitivity,”  71st Device Res. Conf., IEEE, pp. 105–106, 2013.

Educational Resources: nanoHUB-U: Principles of Electronic Nanobiosensors BioSensorLab, P. R. Nair; J. Go; G. J. Landells; T. R. Pandit; M. A. Alam; X. Jin; P. Dak; A. Jain (2014).

Researchers should cite this work as follows:

• Dak, P.; Alam, M. A. (2014). FET pH Sensor Model. nanoHUB. doi:10.4231/D30000150

  BibTex | EndNote

1. Compact Model
2. NEEDS node
3. pH sensors/sensing
4. sensors/sensing

Dated: 06/04/2015

Updates in version 1.0.1

1) Module name changed from pH_model_1_0_0 to pH_model_1_0_1 to match with the file name pH_robust_model_1_0_1.va

2) Unused parameter kT is eliminated from file pH_robust_model_1_0_1.va

3) Indentation in Verilog-A fixed. Tabs replaced by spaces.

4) Directory with names ending in "pvadir" have been removed from the zip archive.

5) New dummy variables are introduced into the code to shorten the length of the equation.

6) pH_model_1_0_1 now includes a warning for the case when the approximation for determination of solution potential is violated.

7) Text in Section 5.1 of the manual had an error which has been corrected. Text "... the metal gate capacitance (CMG) should be larger than ..." has been replaced with "... the metal gate capacitance (CMG) should be smaller than ...". The formula for sensitivity has been corrected to "S=CLG/CMG * (dVT,LG/dpH)".