Ion concentration distribution measuring device

Patent metadata

Field	Value
Publication number	US-10845329-B2
Application number	US-201816481979-A
Country	US
Kind code	B2
Filing date	Feb 8, 2018
Priority date	Feb 16, 2017
Publication date	Nov 24, 2020
Grant date	Nov 24, 2020

Abstract

An ion concentration distribution measurement device includes a unit detection element for outputting charges of an amount according to an ion concentration, and an integration circuit for outputting a signal value according to the amount of charges which are output from the unit detection element. The unit detection element includes a MOS transistor, an ion sensitive portion, a first capacitive portion, and a transfer switch. The integration circuit includes an amplifier, a second capacitive portion, and a reset switch.

First claim

The invention claimed is:

1. An ion concentration distribution measurement device comprising:
a detection unit including a plurality of unit detection elements each configured to output charges of an amount according to an ion concentration arranged and formed one-dimensionally or two-dimensionally on a semiconductor substrate; and
a signal processing unit including one or two or more integration circuits each configured to output a signal value according to the amount of charges output from the unit detection element, wherein
each of the unit detection elements includes:
a MOS transistor including a first electrode, a second electrode, and a gate electrode,
an ion sensitive portion electrically connected to the gate electrode of the MOS transistor, and configured to apply a potential according to the ion concentration to the gate electrode,
a first capacitive portion provided between the second electrode of the MOS transistor and a reference potential input terminal, and configured to accumulate charges of an amount according to the potential of the gate electrode, and
a transfer switch including a first terminal and a second terminal, and configured to output charges accumulated in the first capacitive portion from the second terminal, the first terminal being electrically connected to the second electrode of the MOS transistor,
each of the integration circuits includes:
an amplifier including a first input terminal to which charges output from any one unit detection element among the plurality of unit detection elements are input, a second input terminal to which a reference potential is input, and an output terminal outputting a signal value,
a second capacitive portion provided between the first input terminal and the output terminal of the amplifier, and configured to accumulate charges input to the first input terminal of the amplifier, and
a reset switch provided in parallel with the second capacitive portion, and configured to reset charge accumulation in the second capacitive portion, and
a signal value according to the amount of charges accumulated in the second capacitive portion is output from the output terminal of the amplifier.

2. The ion concentration distribution measurement device according to claim 1 , wherein the ion sensitive portion is provided to cover at least a part of both or any one of the MOS transistor and the transfer switch.

3. The ion concentration distribution measurement device according to claim 1 , wherein one integration circuit is provided corresponding to two or more unit detection elements among the plurality of unit detection elements.

4. The ion concentration distribution measurement device according to claim 1 , wherein
the plurality of unit detection elements are arranged two-dimensionally in M rows and N columns (where M and N are each an integer of 2 or more),
the signal processing unit includes N integration circuits, and
one integration circuit is provided corresponding to M unit detection elements in each column among the plurality of unit detection elements.

5. The ion concentration distribution measurement device according to claim 1 , wherein in each of the unit detection elements, the first electrode of the MOS transistor and the second terminal of the transfer switch are electrically connected to each other.

6. The ion concentration distribution measurement device according to claim 5 , wherein the signal processing unit further includes an accumulation circuit configured to cumulatively add signal values output from the integration circuit.

Assignees

• National Univ Corporation Toyohashi Univ Of Technology
• Hamamatsu Photonics Kk

Inventors

• Sawada Kazuaki
• Yamamoto Hiroo
• Mizuno Seiichiro
• WAKAMORI Toshiki

Classifications

• H10F39/18

  Complementary metal-oxide-semiconductor [CMOS] image sensors; Photodiode array image sensors · CPC title

• G01N27/227

  Sensors changing capacitance upon adsorption or absorption of fluid components, e.g. electrolyte-insulator-semiconductor sensors, MOS capacitors (G01N27/225 takes precedence) · CPC title

• G01N27/4148 Primary

  Integrated circuits therefor, e.g. fabricated by CMOS processing · CPC title

• H01L27/14643

  Electricity · mapped topic