FIELD EFFECT TRANSISTOR FOR DETECTING IONIC MATERIAL AND METHOD OF DETECTING IONIC MATERIAL USING THE SAME

• US 20070252176A1
• Filed: 12/20/2006
• Published: 11/01/2007
• Est. Priority Date: 04/26/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: YOO, Kyu-tae, SHIM, Jeo-young, LEE, Kyu-sang, CHUNG, Won-seok
• Granted Patent: US 8,035,175 B2
• Time in Patent Office: Days
• US Class Current: 257/213
• CPC Class Codes: G01N 27/4145 specially adapted for biomolecules, e.g. gate electrode with immobilised receptors

Abstract

A field effect transistor for detecting ionic material and a method of detecting ionic material using the field effect transistor. The field effect transistor for detecting ionic material includes a substrate formed of a semiconductor material, a source region and a drain region spaced apart from each other in the substrate and doped with an opposite conductivity type to that of the substrate, a channel region interposed between the source region and the drain region, an insulating layer disposed on the channel region and formed of an electrically insulating material, a first reference electrode disposed at an edge of the upper portion of the insulating layer and a second reference electrode disposed to be spaced apart from the insulating layer.

Claims

1. A field effect transistor for detecting ionic material, the field effect transistor comprising:

a substrate formed of a semiconductor material;

a source region and a drain region spaced apart from each other in the substrate and doped with an opposite conductivity type to that of the substrate;

a channel region interposed between the source region and the drain region;

an insulating layer disposed on the channel region and formed of an electrically insulating material;

a first reference electrode disposed at an edge of the upper portion of the insulating layer; and

a second reference electrode disposed to be spaced apart from the insulating layer.

2. The field effect transistor of claim 1, further comprising a separation layer disposed on the source region, the drain region and the first reference electrode and formed of an electrically insulating material.

3. The field effect transistor of claim 2, wherein the second reference electrode is disposed on the separation layer.

4. The field effect transistor of claim 1, wherein the insulating layer is disposed on portions of the source region and the drain region.

5. The field effect transistor of claim 1, wherein the electrically insulating material is silicon dioxide, silicon nitride, or metal oxide.

6. The field effect transistor of claim 1, wherein the source region and the drain region are doped with a p-type material when the substrate is doped with n-type material.

7. The field effect transistor of claim 1, wherein the source region and the drain region are doped with an n-type material when the substrate is doped with a p-type material.

8. The field effect transistor of claim 1, wherein the first reference electrode is formed of one of polysilicon, Al, Pt, Au, and Cu.

9. The field effect transistor of claim 1, wherein the second reference electrode is formed of one of platinum and Ag/AgCl.

10. The field effect transistor of claim 1, wherein the ionic material is a biomolecule.

11. The field effect transistor of claim 10, wherein the biomolecule is one of nucleic acid and protein.

12. The field effect transistor of claim 11, wherein the nucleic acid is selected from the group consisting of DNA, RNA, PNA, LNA and a hybrid thereof.

13. The field effect transistor of claim 11, wherein the protein is selected from the group consisting of an enzyme, a substrate, an antigen, an antibody, a ligand, an aptamer, and a receptor.

14. A microflow apparatus comprising the field effect transistor for detecting ionic material of claim 1.

15. The microflow apparatus of claim 14, wherein the field effect transistor is formed in a micro channel of the microflow apparatus.

16. The microflow apparatus of claim 14, wherein the substrate of the field effect transistor is an inner surface of a micro channel of the microflow apparatus.

17. A method of detecting ionic material, the method comprising:

providing a sample solution used to detect the presence or concentration of ionic material to an insulating layer of a field effect transistor for detecting ionic material; and

measuring electric signal changes of the field effect transistor;

wherein the field effect transistor comprises;

a substrate formed of a semiconductor material;

a source region and a drain region spaced apart from each other in the substrate and doped with an opposite conductivity type to that of the substrate;

a channel region interposed between the source region and the drain region;

the insulating layer disposed on the channel region and formed of an electrically insulating material;

a first reference electrode disposed at an edge of the upper portion of the insulating layer; and

a second reference electrode disposed to be spaced apart from the insulating layer.

18. The method of claim 17, further comprising applying a constant or different voltage to each of the first and second reference electrodes of the field effect transistor before providing the sample solution.

19. The method of claim 17, wherein the sample solution is provided to the first reference electrode and the second reference electrode of the field effect transistor, in addition to the insulating layer.

20. The method of claim 17, wherein an electric signal of the field effect transistor is one of source-drain current and voltage.

21. The method of claim 17, wherein the ionic material is a biomolecule.

22. The method of claim 21, wherein the biomolecule is one of nucleic acid and protein.

23. The method of claim 22, wherein the nucleic acid is selected from the group consisting of DNA, RNA, PNA, LNA and a hybrid thereof.

24. The method of claim 22, wherein the protein is selected from the group consisting of an enzyme, a substrate, an antigen, an antibody, a ligand, an aptamer, and a receptor.

25. The method of claim 22, wherein the nucleic acid is one of a PCR product and a refined product thereof.