Biosensor
A biosensor system includes an array of biosensors with a plurality of electrodes situated proximate the biosensor. A controller is configured to selectively energize the plurality of electrodes to generate a DEP force to selectively position a test sample relative to the array of biosensors.
1. A biosensor system, comprising:
a handling substrate;
an interconnect layer over the handling substrate;
a device substrate over the interconnect layer, the device substrate including a biosensor array electrically connected to the interconnect layer;
an isolation layer over the device substrate;
a plurality of electrodes formed over the isolation layer and extending through the isolation layer and the device substrate to the interconnect layer, the plurality of electrodes configured to receive an AC signal to establish a DEP force to selectively position a test sample relative to the biosensor array, wherein the plurality of electrodes include first, second, third and fourth electrodes positioned on a common plane on respective first, second, third and fourth sides of the biosensor array, and fifth, sixth, seventh and eighth electrodes positioned on the common plane on the respective first, second, third and fourth sides of the biosensor array; and
a reference electrode positioned above the plurality of electrodes and the biosensor array.
2. The biosensor system of claim 1 , further comprising:
a controller electrically connected to the plurality of electrodes, wherein the controller is configured to selectively energize the plurality of electrodes.
3. The biosensor system of claim 2 , wherein the AC signal includes a first AC signal having a first predetermined frequency and a second AC signal having a second predetermined frequency, wherein the reference electrode is configured to receive the first AC signal to establish a positive DEP to trap the test sample on the biosensor array, and the reference electrode is configured to receive the second AC signal to establish a negative DEP to separate the test sample from the biosensor array.
4. The biosensor system of claim 2 , wherein the AC signal includes a first AC signal having a 0 degree phase angle, a second AC signal having a 90 degree phase angle, a third AC signal having a 180 degree phase angle, and a fourth AC signal having a 270 degree phase angle, and wherein the first electrode is configured to receive the first AC signal, the second electrode is configured to receive the second AC signal, the third electrode is configured to receive the third AC signal, and the fourth electrode is configured to receive the fourth AC signal to establish a DEP force to rotate the test sample about a first axis.
5. The biosensor system of claim 4 , wherein the AC signal has a predetermined frequency.
6. The biosensor system of claim 4 , wherein the sixth electrode is configured to receive a fifth AC signal having a first phase angle, and the eighth electrode is configured to receive a sixth AC signal having a second phase angle to establish a DEP force to rotate the test sample about a second axis perpendicular to the first axis.
7. The biosensor system of claim 1 , wherein the biosensor array includes a plurality of backside sensing bioFETs.
8. A method, comprising:
providing a biosensor array;
providing a three-dimensional (3D) test sample;
collecting data regarding a first segment of the 3D test sample by the biosensor array;
generating a DEP force to reposition the 3D test sample relative to the biosensor array, including applying a first AC signal having a 0 degree phase angle to a first electrode positioned on a first side of the biosensor array; applying a second AC signal having a 90 degree phase angle to a second electrode positioned on a second side of the biosensor array; applying a third AC signal having a 180 degree phase angle to a third electrode positioned on a third side of the biosensor array, and applying a fourth AC signal having a 270 degree phase angle to a fourth electrode positioned on a fourth side of the biosensor array;
providing fifth, sixth, seventh and eighth electrodes positioned on the respective first, second, third and fourth sides of the biosensor array;
providing a reference electrode positioned above the first, second, third and fourth electrodes;
collecting data regarding a second segment of the 3D test sample by the biosensor array; and
combining the data regarding the first and second segments of the 3D test sample.
9. The method of claim 8 , wherein generating the DEP force includes generating a positive DEP force to trap the 3D test sample on the biosensor array.
10. The method of claim 8 , wherein generating the DEP force includes generating a negative DEP force to lift the 3D test sample off the biosensor array.
11. The method of claim 8 , wherein generating the DEP force includes generating a rotating DEP force to rotate the 3D test sample about a predetermined axis.
12. The method of claim 8 , wherein generating the DEP force includes generating a rotating DEP force to rotate the 3D test sample about at least one of a first axis, a second axis extending perpendicularly to the first axis, or a third axis extending perpendicularly to the first axis and the second axis.
13. The method of claim 8 , wherein generating the DEP force includes applying a signal having a first predetermined frequency to the reference electrode to establish a positive DEP to trap the 3D test sample on the biosensor array.
14. The method of claim 13 , wherein generating the DEP force includes, applying a signal having a second predetermined frequency to the reference electrode to establish a negative DEP to separate the 3D test sample from the biosensor array.
15. The method of claim 8 , wherein the fifth, sixth, seventh and eighth electrodes are electrically floating.
16. A biosensor system, comprising:
a handling substrate;
an interconnect layer over the handling substrate;
a device substrate over the interconnect layer, the device substrate including a biosensor array electrically connected to the interconnect layer;
an isolation layer over the device substrate; and
a plurality of electrodes formed over the isolation layer and extending through the isolation layer and the device substrate to the interconnect layer, the plurality of electrodes including:
first, second, third and fourth electrodes positioned on a common plane on respective first, second, third and fourth sides of the biosensor array;
fifth, sixth, seventh and eighth electrodes positioned on the common plane on the respective first, second, third and fourth sides of the biosensor array; and
a reference electrode positioned above the first, second, third, fourth, fifth, sixth, seventh and eighth electrodes, and the biosensor array.
17. The biosensor system of claim 16 , wherein the plurality of electrodes configured to receive an AC signal to establish a dielectrophoresis (DEP) force to selectively position a test sample relative to the biosensor array.
18. The biosensor system of claim 17 , further comprising a controller configured to selectively energize the plurality of electrodes to generate the DEP force to selectively position the test sample relative to the biosensor array.
19. The biosensor system of claim 18 , wherein the controller is configured to apply a first AC signal having a first predetermined frequency to the reference electrode, and to apply a second AC signal having a second predetermined frequency to the reference electrode.
20. The biosensor system of claim 16 , wherein the biosensor array includes a plurality of backside sensing bioFETs.