Granted Patent B2

US 8,776,274 · App. 13/665,840 · Granted Jul 15, 2014

Abstract

Claims (31)

1. An integrated circuit package for sensing fluid properties, comprising:

a substrate comprising semiconductor material;

a fluid property measurement circuit formed on the substrate;

a sensor circuit coupled to the fluid property measurement circuit within a same integrated circuit package;

wherein the sensor circuit is configured to generate a field that interacts with the fluid;

wherein the fluid property measurement circuit is configured to determine a change in a property of the sensor circuit as results from the field interacting with the fluid and is further configured to determine a property of the fluid based on the change in the property of the sensor circuit.

2. The integrated circuit package of claim 1 further comprising packaging material configured to prevent direct physical contact of the fluid with the substrate, the fluid property measurement circuit, and the sensor circuit.

3. The integrated circuit package of claim 1 , wherein the sensor circuit comprises at least one inductor component.

4. The integrated circuit package of claim 3 , wherein the at least one inductor component comprises a first inductor component having a first geometry and a second inductor component having a second geometry that is different than the first geometry of the first inductor component.

5. The integrated circuit package of claim 1 , wherein the sensor circuit comprises at least one capacitor component.

6. The integrated circuit package of claim 5 , wherein the at least one capacitor component comprises a first capacitor component having a first geometry and a second capacitor component having a second geometry that is different than the first geometry of the first capacitor component.

7. The integrated circuit package of claim 5 , wherein the at least one capacitor component comprises at least one interdigitated comb capacitor.

8. The integrated circuit package of claim 1 , wherein the sensor circuit comprises at least one inductor component and at least one capacitor component.

9. The integrated circuit package of claim 1 , wherein the sensor circuit and the fluid property measurement circuit are formed on a same integrated circuit chip.

10. The integrated circuit package of claim 9 , wherein the sensor circuit is formed in at least a top metal layer of the integrated circuit chip.

11. The integrated circuit of claim 10 , wherein the integrated circuit chip further comprises a passivation layer covering the top metal layer.

12. The integrated circuit of claim 11 , wherein the passivation layer comprises at least one of silicon oxide, silicon nitride, or silicon oxi-nitride.

13. The integrated circuit package of claim 1 further comprising a reference circuit formed on the substrate and coupled to the fluid property measurement circuit, wherein the reference circuit is configured to generate a field that matches the field generated by the sensor circuit in a known calibration state.

14. The integrated circuit package of claim 1 further comprising a passivation layer and a metal layer between the sensor circuit and the fluid property measurement circuit, wherein the sensor circuit is formed on the passivation layer.

15. The integrated circuit package of claim 1 further comprising a metal layer formed on the substrate and a passivation layer covering the metal layer, wherein the sensor circuit is formed in at least the metal layer, and wherein the passivation layer is fabricated with at least one groove to receive the liquid.

16. A method of fabricating an integrated circuit package for sensing fluid properties, the method comprising:

forming a fluid property measurement circuit on a substrate;

forming a sensor circuit that is configured to generate a field that interacts with a fluid and covering the sensor circuit with a passivation layer, wherein the sensor circuit and the fluid property measurement circuit are electrically coupled together and formed within a same integrated circuit package, wherein the fluid property measurement circuit is configured to determine a change in a property of the sensor circuit as results from the field interacting with the fluid and is further configured to determine a property of the fluid based on the change in the property of the sensor circuit;

enclosing the substrate, the fluid property measurement circuit, the sensor circuit, the reference circuit and the passivation layer in packaging material that is impenetrable by the fluid.

17. A method performed by an integrated circuit package for determining fluid properties, the method comprising:

sensing a property of a fluid using a first field that is generated by a sensor circuit and that interacts with the fluid;

determining, by a fluid property measurement circuit formed on a substrate and coupled to the sensor circuit within a same integrated circuit package, a change in a property of the sensor circuit associated with the first field interacting with the fluid;

determining, by the fluid property measurement circuit, the sensed property of the fluid using the determined change in the property of the sensor circuit.

18. The method of claim 17 , wherein determining the change in the property of the sensor circuit comprises determining a change in resonant frequency of the sensor circuit.

19. The method of claim 18 , wherein determining the change in resonant frequency of the sensor circuit comprises comparing a first resonant frequency measured for the sensor circuit while the first field interacts with the fluid to a second resonant frequency of a reference circuit within the same integrated circuit package and positioned to prevent a second field generated by the reference circuit from interacting with the fluid.

20. The method of claim 17 , wherein the sensing is performed without the fluid physically contacting the substrate, the fluid property measurement circuit, or the sensor circuit.

Assignments (30)