Particle inspection system and driving method employed therein

Patent metadata

Field	Value
Publication number	US-10533934-B2
Application number	US-201715408702-A
Country	US
Kind code	B2
Filing date	Jan 18, 2017
Priority date	Jul 18, 2014
Publication date	Jan 14, 2020
Grant date	Jan 14, 2020

Abstract

According to one embodiment, a particle inspection system includes a voltage driving circuit which applies a driving voltage for a particle inspection to a particle inspection chip, a current-voltage conversion circuit which converts, into a voltage signal, a current signal output from the particle inspection chip when the driving voltage is applied to the particle inspection chip, a detection circuit which detects, based on the voltage signal, whether the sample liquid is introduced into a detection region of the particle inspection chip, and an analysis circuit which analyzes the fine particle, in the sample liquid based on the voltage signal. The voltage driving circuit varies the driving voltage based on the detection result of the detection circuit.

First claim

What is claimed is:

1. A particle inspection system comprising:
a voltage driving circuit which applies a driving voltage for particle inspection between two electrodes of a particle inspection chip, wherein the particle inspection chip detects a fine particle in a sample liquid based on a current flowing between the two electrodes and outputs a current signal indicative of the fine particle;
a current-voltage conversion circuit which converts, into a voltage signal, the current signal output from the particle inspection chip when the driving voltage is applied;
a detection circuit which detects, based on the voltage signal, whether the sample liquid is introduced into a detection region of the particle inspection chip; and
an analysis circuit which analyzes the fine particle in the sample liquid based on the voltage signal,
wherein the voltage driving circuit varies the driving voltage based on a detection result of the detection circuit, and
wherein the voltage driving circuit applies a first driving voltage before the sample liquid is introduced into the detection region and applies a second driving voltage in response to the detection circuit detecting introduction of the sample liquid, wherein the first and second driving voltages are both nonzero and are different values from each other.

2. The system of claim 1 , wherein the second driving voltage is higher than the first driving voltage.

3. The system of claim 2 , wherein a time required for the driving voltage to shift from the first driving voltage to the second driving voltage is 10 μs or more.

4. The system of claim 1 , wherein the particle inspection chip comprises:
a channel provided in a surface portion of a semiconductor substrate and permitting the sample liquid to pass therethrough, and
a micropore provided at part of the channel for passing therethrough the fine particle in the sample liquid.

5. The system of claim 1 , wherein the particle inspection chip comprises:
a first channel provided in a surface portion of a semiconductor substrate and permitting the sample liquid to pass therethrough,
a second channel provided in a surface portion of the semiconductor substrate different from the surface portion of the first channel and permitting the sample liquid or an electrolyte to pass therethrough,
a contact portion at which part of the first channel is adjacent to or intersects part of the second channel with a partition interposed therebetween, and
a micropore provided in the partition for passing the fine particle therethrough.

6. The system of claim 1 , wherein the particle inspection chip and a part of each circuit or each entire circuit are provided on a single semiconductor substrate.

7. A particle inspection system comprising:
a current driving circuit which applies a driving voltage for particle inspection between two electrodes of a particle inspection chip, to cause a constant current to flow in a detection region of the particle inspection chip, wherein the particle inspection chip detects a fine particle in a sample liquid and outputs a current signal indicative of the fine particle;
a current-voltage conversion circuit which converts, into a voltage signal, the current signal output from the particle inspection chip when the driving voltage is applied;
a detection circuit which detects whether the sample liquid is introduced into the detection region of the particle inspection chip, based on the voltage signal obtained by the current-voltage conversion circuit or the driving voltage applied by the current driving circuit; and
an analysis circuit which analyzes the fine particle in the sample liquid based on the voltage signal,
wherein the current driving circuit varies a value of the driving voltage to cause the current to vary in response to a detection result of the detection circuit.

8. The system of claim 7 , wherein the current driving circuit applies a first driving voltage before the sample liquid is introduced into the detection region and applies a second driving voltage after the sample liquid is introduced into the detection region and the detection circuit detects the sample liquid,
wherein the first and second driving voltages are both nonzero, and
wherein the second driving voltage is higher than the first driving voltage.

9. The system of claim 8 , wherein a time required for the driving voltage to shift from the first driving voltage to the second driving voltage is 10 μs or more.

10. The system of claim 7 , wherein the particle inspection chip comprises:
a channel provided in a surface portion of a semiconductor substrate and permitting the sample liquid to pass therethrough, and
a micropore provided at part of the channel for passing therethrough the fine particle in the sample liquid.

11. The system of claim 7 , wherein the particle inspection chip comprises:
a first channel provided in a surface portion of a semiconductor substrate and permitting the sample liquid to pass therethrough,
a second channel provided in a surface portion of the semiconductor substrate different from the surface portion of the first channel and permitting the sample liquid or an electrolyte to pass therethrough,
a contact portion at which part of the first channel is adjacent to or intersects part of the second channel with a partition interposed therebetween, and
a micropore provided in the partition for passing the fine particle therethrough.

12. The system of claim 7 , wherein the particle inspection chip and a part of each circuit or each entire circuit are provided on a single semiconductor substrate.

13. A driving method for the particle inspection system recited in claim 1 , the driving method comprising:
detecting, using the detection circuit, whether the sample liquid is introduced into the detection region, with the first driving voltage being applied between the two electrodes of the particle inspection chip;
applying the second driving voltage between the two electrodes of the particle inspection chip in response to introduction of the sample liquid into the detection region being detected; and
analyzing the fine particle in the sample liquid, using the analysis circuit and based on the voltage signal obtained by the current-voltage conversion circuit with the second driving voltage being applied.

14. The driving method of claim 13 , wherein the second driving voltage is higher than the first driving voltage.

15. The driving method of claim 14 , wherein a time required for the driving voltage to shift from the first driving voltage to the second driving voltage is 10 μs or more.

16. The driving method of claim 13 , wherein the particle inspection chip comprises:
a channel provided in a surface portion of a semiconductor substrate and permitting the sample liquid to pass therethrough, and
a micropore provided at part of the channel for passing therethrough the fine particle in the sample liquid.

17. The driving method of claim 13 , wherein the particle inspection chip comprises:
a first channel provided in a surface portion of a semiconductor substrate and permitting the sample liquid to pass therethrough,
a second channel provided in a surface portion of the semiconductor substrate different from the surface portion of the first channel and permitting the sample liquid or an electrolyte to pass therethrough,
a contact portion at which part of the first channel is adjacent to or intersects part of the second channel with a partition interposed therebetween, and
a micropore provided in the partition for passing the fine particle therethrough.

Assignees

• Toshiba Kk

Inventors

• Nishigaki Michihiko
• Hamasaki Hiroshi
• Nakamura Naofumi
• Kobayashi Kentaro
• Miki Hiroko

Classifications

• G01N15/12 Primary

  by observing changes in resistance or impedance across apertures when traversed by individual particles, e.g. by using the Coulter principle · CPC title

• G01N15/1031

  by measuring electrical or magnetic effects · CPC title

• G01N15/1056 Primary

  Physics · mapped topic

• G01N2015/1254

  Physics · mapped topic

• G01N15/1209

  Physics · mapped topic