Biomolecule measuring device

A biomolecule measuring apparatus comprises a semiconductor sensor for detecting ions generated by a reaction between a biomolecular sample and a reagent,

• wherein the semiconductor sensor comprises:
• a semiconductor substrate;
• a plurality of cells arranged in an array form on the semiconductor substrate, each of the plurality of cells is configured to detect ions;
• and
• a plurality of readout wires arranged in the array formed by the plurality of cells,
• wherein each of the plurality of cells comprises:
• an ISFET comprising a floating gate and configured to detect a change in ion concentration;
• a first MOSFET comprising a gate configured to receive an output from the ISFET and amplify the output from the ISFET;
• a second MOSFET in series to the first MOSFET, configured to selectively transmit an output from the first MOSFET to a corresponding readout wire of the plurality of readout wires;
• a third MOSFET in series to the ISFET, configured to generate hot electrons in the ISFET and to inject a charge to the floating gate of the ISFET;
• and,
• a fourth MOSFET connected to the ISFET, configured to prevent the application of a high voltage to the first MOSFET;
• wherein the third MOSFET is controlled based on the output received from the ISFET, and wherein the second MOSFET and the third MOSFET are separately controlled;
• and
• wherein the biomolecule measuring apparatus is configured to transmit the output from the ISFET to the corresponding readout wire and determine whether a threshold voltage of the ISFET is within a predetermined range, by controlling the second MOSFET.