JST  Vol.3 No.3 , September 2013
An Integrated ISFET pH Microsensor on a CMOS Standard Process
ABSTRACT
We present the design and integration of a nine-pH microsensor array on a single silicon substrate with its own signal readout circuit, integrated in a 0.6-μm commercial standard complementary metal oxide semiconductor (CMOS) process. An ion sensitive field effect transistor (ISFET) has been used as pH microsensor and an instrumentation amplifier as the read-out circuit. The ISFET structure is conformed by the channel length and ratio of MOS transistor, gate extended and the selective membrane, for which silicon nitride (Si3N4) is employed as an ion selective element. The complete design includes shielding around the pH microsensor and the readout circuit to avoid leakage of current to the substrate. The readout circuit is composed by three operational amplifiers and resistances that form the instrumentation amplifier, with a ±2.5 V bias has a 50 dB gain, power supply rejection ratio (PSSR) of 120 dB and common mode rejection ratio (CMRR) of 127 dB. The complete system is integrated in a 1.12 mm2 silicon area; it presents a 59 mV/pH linearity, within a concentration range of 2 to 12 of pH level, making it a good alternative for biological or medical applications.

Cite this paper
F. López-Huerta, R. Woo-Garcia, M. Lara-Castro, J. Estrada-López and A. Herrera-May, "An Integrated ISFET pH Microsensor on a CMOS Standard Process," Journal of Sensor Technology, Vol. 3 No. 3, 2013, pp. 57-62. doi: 10.4236/jst.2013.33010.
References
[1]   P. Bergveld, “Development of an Ion Sensitive Solid State Device for Neurophysiological Measurements,” IEEE Transactions on Biomedical Engineering, Vol. 17, No. 1, 1970, pp. 70-71.

[2]   C. Soo, S. K. Kim and M. Kim, “Ion Sensitive Field Effect Transistor for Biological Sensing,” Sensors, Vol. 9, No. 9. 2009, pp. 7111-7131, doi:10.3390/s90907111

[3]   P. Bergveld, “The Operation of an ISFET as an Electron Device,” Sensors and Actuators, Vol. 1, 1981, pp. 17-29. doi:10.1016/0250-6874(81)80004-2

[4]   P. Bergveld, “The Future of Biosensors,” Sensors and Actuators A: Physical, Vol. 56, No. 1-2, 1996, pp. 65-73. doi:10.1016/0924-4247(96)01275-7

[5]   K. M. Chang, C. T. Chang and K. M. Chan, “Development of an Ion Sensitive Field Effect Transistor Based Urea Biosensor with Solid State Reference Systems,” Sensors, Vol. 10, No. 6, 2010, pp. 6115-6127. doi:10.3390/s100606115

[6]   G. Shalev, A. Cohen, A. Doron, A. Machauf, M. Horesh, U. Virobnik, D. Ullien and L. Ilan, “Standard CMOS Fabrication of a Sensitive Fully Depleted Electrolyte-Insulator-Semiconductor Field Effect Transistor for Biosensor Applications,” Sensors, Vol. 9, No. 6, 2009, pp. 4366-4379. doi:10.3390/s90604366

[7]   M. J. Sch?ning and A. Poghossian, “Recent Advances in Biologically Sensitive Field-Effect Transistors (BioFETs),” Analyst, Vol. 127, No. 6, 2002, pp. 1137-1151. doi:10.1039/b204444g

[8]   W. Olthuis, “Chemical and Physical FET-Based Sensors or Variations on an Equation,” Sensors and Actuators B: Chemical, Vol. 105, No. 1, 2005, pp. 96-103. doi:10.1016/j.snb.2004.02.040

[9]   G. P. Chen, R. M. Xia, J. Gong and W. D. Shou, “Study on pH Effect in Process of an Entero-Gastric Fiber-Optic Sensor Design,” Sensors, Vol. 2, No. 11, 2002, pp. 447-454. doi:10.3390/s21100447

[10]   G. Beltrán-Pérez, F. López-Huerta, S. Mu?oz-Aguirre, J. Castillo-Mixcoatl, R. Palomino-Merino, R. Lozada-Morales and O. Portillo-Moreno, “Fabrication and Characterization of an Optical Fiber pH Sensor Using Sol-Gel Deposited TiO2 Film Doped with Organic Dyes,” Sensors and Actuators B: Chemical, Vol. 120, No. 6, 2006, pp. 74-78. doi:10.1016/j.snb.2006.01.048

[11]   C.-L. Dai, P.-W. Lu, C.-C. Wu and C. Chang, “Fabrication of Wireless Micro Pressure Sensor Using the CMOS Process,” Sensors, Vol. 9, No. 11, 2009, pp. 8748-8760. doi:10.3390/s91108748

[12]   E. Lauwers, J. Suls, W. Gumbrecht, D. Maes, G. Gielen and W. Sansen, “A CMOS Multiparameter Biochemical Microsensor with Temperature Control and Signal Interfacing,” IEEE Journal of Solid-State Circuits, Vol. 36, No. 12, 2001, pp. 2030-2038. doi:10.1109/4.972154

[13]   A. Morgenshtein, L. Sudakov-Boreysha, U. Dinnar, C. G. Jakobson and Y. Nemirovsky, “CMOS Readout Circuitry for ISFET Microsystems,” Sensors and Actuators B: Chemical, Vol. 97, No. 1, 2004, pp. 122-131. doi:10.1016/j.snb.2003.08.007

[14]   V. P. Chodavarapu, A. H. Titus and A. N. Cartwright, “Differential Read out Architecture for CMOS ISFET Microsystems,” Electronics Letters, Vol. 41, No. 12, 2005, pp. 698-699. doi:10.1049/el:20051044

[15]   M. Futagawa, T. Iwasaki, H. Murata, M. Ishida and K. Sawada, “A Miniature Integrated Multimodal Sensor for Measuring pH, EC and Temperature for Precision Agriculture,” Sensors, Vol. 12, No. 6, 2012, pp. 8338-8354. doi:10.3390/s120608338

[16]   C. Jimenez-Jorquera, J. Orozco and A. Baldi, “ISFET Based Microsensors for Environmental Monitoring,” Sensors, Vol. 10, No. 1, 2012, pp. 61-83. doi:10.3390/s100100061

[17]   S. Martinoia, N. Rosso, M. Grattarola, L. Lorenzelli, B. Margesin and M. Zen, “Development of ISFET Array-Based Microsystems for Bioelectrochemical Measurements of Cell Populations,” Biosensors and Bioelectronics, Vol. 16, No. 9-12, 2001, pp. 1043-1050. doi:10.1016/S0956-5663(01)00202-0

[18]   V. P. Chodavarapu, A. H. Titus and A. N. Cartwright, “CMOS ISFET Microsystem for Biomedical Applications,” Proceedings of IEEE Sensors Conference, Irvine, 30 October-3 November 2005, pp. 109-112.

[19]   Y. I. Huang, R. S. Huang and L. L. His, “A New Structured ISFET with Integrated Ti/PdAg/AgCl Electrode and Micromachined Back-Side P+ Contacts,” Journal of the Chinese Institute of Engineers, Vol. 25, No. 3, 2002, pp. 327-334. doi:10.1080/0253389.2002.9670707

[20]   C. Lung, Y. Chuan, T. Ping, H. Kwei, W. Yaw and S. Kan, “A Novel SnO2/Al Discrete Gate ISFET pH Sensor with CMOS Standard Process,” Sensors and Actuators B: Chemical, Vol. 75, No. 1-2, 2001, pp. 36-42. doi:10.1016/S0925-4005(00)00739-5

[21]   K.-M. Chang, C.-T. Chang, K.-Y. Chao and C.-H. Lin, “A Novel pH-Dependent Drift Improvement Method for Zirconium Dioxide Gated pH-Ion Sensitive Field Effect Transistors,” Sensors, Vol. 10, No. 5, 2010, pp. 4643-4654. doi:10.3390/s100504643

[22]   G. Scarpa, A.-L. Idzko, A. Yadav and S. Thalhammer, “Organic ISFET Based on Poly (3-hexylthiophene),” Sensors, Vol. 10, No. 3, 2010, pp. 2262-2273. doi:10.3390/s100302262

[23]   A. Loi, I. Manunza and A. Bonfiglio, “Flexible, Organic, Ion-Sensitive Field-Effect Transistor,” Applied Physics Letters, Vol. 86, No. 10, 2005, pp. 103512-1-103512-3. doi:10.1063/1.1873051

[24]   S. S. Jan, Y. C. Chen, J. C. Chou, P. J. Jan and C. C. Cheng, “Preparation and Properties of Hydrogen Ion-Sensitive Field Effect Transistors with Sol-Gel-Derived Mg-Modified Lead Titanate Gate,” Journal of Non-Crystalline Solids, Vol. 332, No. 1, 2003, pp. 11-19. doi:10.1016/j.jnoncrysol.2003.08.054

[25]   I. Poels, R. B. M. Schasfoort, S. Picioreanu, J. Frank, G. W. K. van Demen, A. van den Berg and L. Nagels, “An ISFET Based Anion Sensor for Potentiometric Detection of Organic Acids in Liquid Chromatography,” Sensors and Actuators B: Chemical, Vol. 67, No. 3, 2000, pp. 249-299.doi:10.1016/S0925-4005(00)00531-1

[26]   F. Yan, P. Estrela, Y. Mo, P. Migliorato and H. Maeda, “Polycrystalline Silicon ISFETs on Glass Substrate,” Sensors, Vol. 5, No. 4, 2005, pp. 293-301. doi:10.3390/s5040293

[27]   C. Moldovan, R. Iosub, M. Modreanu, D. Ulieru, B. Firtat and M. Ion, “ISFET Microsensors HfO2 Based for Biomedical Applications,” International Semiconductor Conference, Sinaia, 27-29 September 2006, pp. 185-188,

[28]   S. P. Lee, J. G. Lee and S. Chowdhury, “CMOS Humidity Sensor System Using Carbon Nitride Film as Sensing Materials,” Sensors, Vol. 8, No. 4, 2008, pp. 2662-2672. doi:10.3390/s8042662

[29]   C. G. Ahn, A. Kim, C. W. Park, C. S. Ah, J. H. Yang, T. Y. Kim, M. Jang and G. Y. Sung, “Modified Ion Sensitive Field Effect Transistor Sensors Having an Extended Gate on a Thick Dielectric,” Applied Physics Letters, Vol. 96, No. 20, 2010, pp. 203702-1-203702-3. doi:10.1063/1.3431296

[30]   K. Nakazato, “An Integrated ISFET Sensor Array,” Sensors, Vol. 9, No. 11, 2009, pp. 8831-8851. doi:10.3390/s91108831

[31]   K. Cao, “A Chemical Sensor Design Using a Standard CMOS Process,” Master’s Thesis, University of Manitoba, Winnipeg, 2007.

[32]   R. M. Woo-García, F. López-Huerta, J. J. Estrada-López and B. S. Soto, “S. Electrochemical pH Sensor Integrated with Standard CMOS Process,” Ingeniería, Vol. 15, No. 2, 2011, pp. 69-79.

[33]   “On Semiconductor?,” 2012. http://www.onsemi.com/

[34]   “Electronic Design,” 2012. http://www.tannereda.com/

[35]   F. López-Huerta, J. J. Estrada-López, M. Linares-Aranda, C. Zú?iga-Islas and B. S. Soto, “Study and Comparison of CMOS Layouts for Applications in Analog Circuits,” Journal of Scientific and Industrial Research, Vol. 71, No. 4, 2012, pp. 257-261.

[36]   “Integrated Circuit Foundry,” 2012. http://www.mosis.com/

 
 
Top