Field-effect transistor, single-electron transistor and sensor using the same
A sensor capable of detecting detection targets that are necessary to be detected with high sensitivity is provided. It comprises a field-effect transistor 1 A having a substrate 2 , a source electrode 4 and a drain electrode 5 provided on said substrate 2 , and a channel 6 forming a current path between said source electrode 4 and said drain electrode 5; wherein said field-effect transistor 1 A comprises: an interaction-sensing gate 9 for immobilizing thereon a specific substance 10 that is capable of selectively interacting with the detection targets; and a gate 7 applied a voltage thereto so as to detect the interaction by the change of the characteristic of said field-effect transistor 1 A.
1. A sensor for detecting a detection target, the sensor comprising:
a field effect transistor having
a substrate,
a source electrode overlying the substrate and a drain electrode overlying the substrate, and
a channel forming a current path between the source electrode and the drain electrode;
an insulator overlying the substrate and covering a portion of the channel;
an interaction-sensing gate overlying the insulator, the interaction-sensing gate having a specific substance that is capable of selectively interacting with the detection target;
a gate for applying a gate voltage to adjust a characteristic of the field-effect transistor;
wherein the detection target changes the characteristic of the field-effect transistor when interacting with the specific substance;
wherein the interaction-sensing gate is not in direct contact with the source electrode and is not in direct contact with the drain electrode.
2. The sensor of claim 1 , wherein the interaction-sensing gate is spaced from the substrate by the insulator.
3. The sensor of claim 1 , wherein the channel comprises a carbon nano tube, the carbon nano tube being bent between the source electrode and the drain electrode at room temperature.
4. The sensor of claim 1 , further comprising an insulator layer having a low-permittivity insulating material.
5. The sensor of claim 1 , wherein the specific substance is disposed on a same side of the sensor as the source electrode and drain electrode.
6. The sensor of claim 1 , wherein the characteristic is a threshold of a Coulomb Oscillation, a Coulomb Oscillation period, a threshold of a Coulomb Diamond, or a Coulomb Diamond period.
7. A field-effect transistor used for a sensor to detect a detection target, the field effect transistor comprising:
a substrate;
a source electrode overlying the substrate and a drain electrode overlying the substrate;
a channel forming a current path between the source electrode and the drain electrode;
an insulator overlying the substrate and covering a portion of the channel;
an interaction-sensing gate overlying the insulator, the interaction-sensing gate having a specific substance that is capable of selectively interacting with the detection target;
a gate for applying a gate voltage to adjust a characteristic of the field-effect transistor;
wherein the detection target changes the characteristic of the field-effect transistor when interacting with the specific substance;
wherein the interaction-sensing gate is not in direct contact with the source electrode and is not in direct contact with the drain electrode.
8. The field effect transistor of claim 7 , wherein the interaction-sensing gate is spaced from the substrate by the insulator.
9. The field effect transistor of claim 7 , wherein the channel comprises a carbon nano tube, the carbon nano tube being bent between the source electrode and the drain electrode at room temperature.
10. The field effect transistor of claim 7 , further comprising an insulator layer having a low-permittivity insulating material.
11. The field effect transistor of claim 7 , wherein the specific substance is disposed on a same side of the sensor as the source electrode and drain electrode.
12. The field effect transistor of claim 7 , wherein the characteristic is a threshold of a Coulomb Oscillation, a Coulomb Oscillation period, a threshold of a Coulomb Diamond, or a Coulomb Diamond period.
13. A sensor for detecting a detection target, the sensor comprising:
a single-electron transistor having
a substrate,
a source electrode overlying the substrate and a drain electrode overlying the substrate, and
a channel forming a current path between the source electrode and the drain electrode;
an insulator overlying the substrate and covering a portion of the channel;
an interaction-sensing gate overlying the insulator, the interaction-sensing gate having a specific substance that is capable of selectively interacting with the detection target;
a gate for applying a gate voltage to adjust a characteristic of the field-effect transistor;
wherein the detection target changes the characteristic of the field-effect transistor when interacting with the specific substance;
wherein the interaction-sensing gate is not in direct contact with the source electrode and is not in direct contact with the drain electrode.
14. The sensor of claim 13 , wherein the interaction-sensing gate is spaced from the substrate by the insulator.
15. The sensor of claim 13 , wherein the channel comprises a carbon nano tube, the carbon nano tube being bent between the source electrode and the drain electrode at room temperature.
16. The sensor of claim 13 , further comprising an insulator layer having a low-permittivity insulating material.
17. The sensor of claim 13 , wherein the specific substance is disposed on a same side of the sensor as the source electrode and drain electrode.
18. The sensor of claim 13 , wherein the characteristic is a threshold of a Coulomb Oscillation, a Coulomb Oscillation period, a threshold of a Coulomb Diamond, or a Coulomb Diamond period.
19. A single-electron transistor for a sensor to detect a detection target, the single-electron transistor comprising:
a substrate;
a source electrode overlying the substrate and a drain electrode overlying the substrate;
a channel forming a current path between the source electrode and the drain electrode;
an insulator overlying the substrate and covering a portion of the channel;
an interaction-sensing gate overlying the insulator, the interaction-sensing gate having a specific substance that is capable of selectively interacting with the detection target;
a gate for applying a gate voltage to adjust a characteristic of the field-effect transistor;
wherein the detection target changes the characteristic of the field-effect transistor when interacting with the specific substance;
wherein the interaction-sensing gate is not in direct contact with the source electrode and is not in direct contact with the drain electrode.
20. The single-electron transistor of claim 7 , wherein the interaction-sensing gate is spaced from the substrate by the insulator.
21. The single-electron transistor of 19 , wherein the channel comprises a carbon nano tube, the carbon nano tube being bent between the source electrode and the drain electrode at room temperature.
22. The single-electron transistor of claim 19 , further comprising an insulator layer having a low-permittivity insulating material.
23. The single-electron transistor of claim 19 , wherein the specific substance is disposed on a same side of the sensor as the source electrode and drain electrode.
24. The single-electron transistor of claim 19 , wherein the characteristic is a threshold of a Coulomb Oscillation, a Coulomb Oscillation period, a threshold of a Coulomb Diamond, or a Coulomb Diamond period.