Volume 10 Issue 3 - May 2018

  • 1. Highly sensitive compact isfet electro-chemical sensor in avalanche region of operation

    Authors : Mohammad Mohiuddin Uzzal

    Pages : 7-12

    DOI : http://dx.doi.org/10.21172/1.103.02

    Keywords : Sensitivity; CMOS Compatibility; pH-to-current; ISFET; Avalanche region; Avalanche multiplication; Electro-Chemical sensor

    Abstract :

    In this paper we present an analytical model of sensitivity for ion sensitive field effect transistor (ISFET) in different region of operation, including Avalanche region. Electro-chemical based ISFET sensor performance is heavily dependent on DC bias and operational region of the sensor. Here, we present a comparative analysis of ISFET sensitivity while the operational region is changed. Using our developed model, we find an optimum bias point to ensure maximum sensitivity from a tiny nanoscale ISFET sensor. Based on SPICE simulations, it is shown that for a minimum size N-type ISFET (W/L=2) using TSMC's 0.25um fabrication process, we can achieve the sensitivity of about 14nA of current change per unit change of pH. However, we can derive higher sensitivity from the same device by operating the device in avalanche region of operation with high avalanche multiplication factor, M.

    Citing this Journal Article :

    Mohammad Mohiuddin Uzzal, "Highly sensitive compact isfet electro-chemical sensor in avalanche region of operation", https://www.ijltet.org/journal_details.php?id=932&j_id=4592, Volume 10 Issue 3 - May 2018, 7-12, #ijltetorg