Methods and apparatus including array of reaction chambers over array of chemFET sensors for measuring analytes

1. A method for manufacturing a semiconductor device, comprising:

forming an array of chemically-sensitive field effect transistor (chemFET) sensors, each chemFET sensor in the array of chemFET sensors having a floating gate structure including a sensing surface formed on a top metal layer of the floating gate structure;

depositing a dielectric layer over the array of chemFET sensors;

etching the dielectric layer to define an array of reaction chambers; each reaction chamber in the array of reaction chambers exposing a corresponding sensing surface of a floating gate structure; and

depositing a sensing material within the array of reaction chambers and at least partially on each reaction chamber sidewall, wherein each reaction chamber in the array of reaction chambers includes a sensing layer comprising the sensing material in contact with the sensing surface of a floating gate structure.

2. The method of claim 1 , wherein the sensing layer in contact with the sensing surface is an electrically conductive layer.

3. The method of claim 2 , wherein the electrically conductive layer comprises a metal, a metal oxide, a metal nitride or a metal oxynitride.

4. The method of claim 3 , wherein the metal of the conductive layer comprises aluminum, zirconium, titanium, tantalum, molybdenum, hafnium or tungsten, and combinations thereof.

5. The method of claim 4 , wherein a native oxide is formed on the metal comprising the conductive layer.

6. The method of claim 1 , wherein the method further comprises applying a buffering inhibitor to the array of reaction chambers.

7. The method of claim 1 , wherein the array of chemFET sensors is configured to provide an output signal dependent on a threshold voltage.

8. The method of claim 7 , wherein the array of chemFET sensors is configured to provide a range of threshold voltage changes between approximately 0 to 2 volts.

9. The method of claim 1 , wherein the sensing surface is sensitive to hydrogen ions.

10. The method of claim 9 , wherein the sensing surface has a pH sensitivity of between about 30 mV/pH to about 60 mV/pH.

11. The method of claim 1 , wherein the sensing surface is sensitive to pyrophosphate or phosphate ions.

12. The method of claim 1 , wherein depositing the dielectric layer comprises depositing at least one of silicon oxide, silicon nitride and silicon oynitride.

13. The method of claim 1 , wherein forming the array of chemFET sensors comprises forming an array of chemFET sensors with a pitch of 10 μm or less.

14. The method of claim 1 , wherein forming the array of chemFET sensors comprises forming an array of at least 10{circumflex over ( )}6 chemFET sensors.

15. The method of claim 1 , wherein after depositing the layer of sensing material within the array of reaction chambers the method further comprises:

attaching a flow cell structure to the semiconductor device to form a semicondutor apparatus configured to provide a flow channel over the array of reaction chambers.

16. The method of claim 15 , wherein the flow cell structure of the semicondutor apparatus has an inlet and outlet port.

17. The method of claim 16 , wherein the inlet port and outlet port are configured to provide connection of the semiconductor apparatus to a fluid delivery system and a waste receptacle, respectively.

18. The method of claim 15 , wherein the flow cell structure is configured to provide uniform transit time of liquids through the flow channel of the semiconductor apparatus.

19. The method of claim 18 , the flow cell structure comprises a flow cross section including a curved wall providing a uniform fluid flow front over the semiconductor device.

20. The method of claim 15 , wherein the flow cell structure is configured to minimize dead volume within the semiconductor apparatus.