MICROSENSOR WITH INTEGRATED TEMPERATURE CONTROL

• US 20130010826A1
• Filed: 07/05/2011
• Published: 01/10/2013
• Est. Priority Date: 07/05/2011
• Status: Active Grant

• Current Assignee: Stmicroelectronics Pte Limited (STMicroelectronics NV)
• Original Assignee: Stmicroelectronics Pte Limited (STMicroelectronics NV)
• Inventors: Le Neel, Olivier, Cherian, Suman, Shankar, Ravi
• Granted Patent: US 9,448,198 B2
• Time in Patent Office: Days
• US Class Current: 374/142
• CPC Class Codes: G01N 27/3272 Test elements therefor, i.e. disposable laminated substrates with electrodes, reagent and channels optical biosensors G01N33/52
• CPC Class Codes: G01N 33/49 Blood chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80

Abstract

Microsensors that include an integrated thermal energy source and an integrated temperature sensor are capable of providing localized heating and temperature control of individual sensing regions within the microsensor. Localized temperature control allows analyte detection to be carried out at the same temperatures or substantially the same temperatures at which the sensor is calibrated. By carrying out the sensing near the calibration temperature, more accurate results can be obtained. In addition, the temperature of the sensing region can be controlled so that chemical reactions involving the analyte in the sensing region occur near their peak reaction rate. Carrying out the sensing near the peak reaction rate improves the sensitivity of the sensor which is important as sensor dimensions decrease and the magnitude of the generated signals decreases.

Claims

1. A semiconductor device for detecting an analyte in a sample, the semiconductor device including a sensor comprising:

a sensing region formed over a semiconductor substrate, the sensing region including a transducer configured to detect an interaction between the sensing region and the analyte;

an integrated thermal energy source underlying the sensing region, the thermal energy source configured to produce thermal energy; and

an integrated temperature sensor adjacent the sensing region, the integrated temperature sensor configured to sense temperature of the sensing region.

2. The semiconductor device of claim 1, wherein the transducer is selected from electrochemical transducers, optical transducers, calorimetric transducers, acoustic transducers, and gravimetric transducers.

3. The semiconductor device of claim 1, wherein the transducer is an electrochemical transducer.

4. The semiconductor device of claim 1, wherein the temperature sensor is above the thermal energy source.

5. The semiconductor device of claim 1, wherein the temperature sensor is below the transducer.

6. The semiconductor device of claim 1, further comprising a thermal conducting layer between the thermal energy source and the sensing region.

7. The semiconductor device of claim 1, wherein the transducer includes a working electrode and a counter electrode and the interaction occurs between the analyte, working electrode and counter electrode.

8. A system for detecting an analyte in a sample, the system comprising:

a semiconductor device component including a sensor for detecting the analyte in the sample, the sensor including;

a sensing region formed over a semiconductor substrate, the sensing region including a transducer configured to detect an interaction between the analyte and the sensing region;

an integrated thermal energy source underlying the sensing region, the thermal energy source configured to produce thermal energy; and

an integrated temperature sensor adjacent the sensing region, the integrated temperature sensor configured to sense temperature of the sensing region; and

a control component configured to receive a signal from the integrated temperature sensor and provide a signal to the thermal energy source in response to the signal received from the integrated temperature sensor.

9. A method for forming a semiconductor device used for detecting an analyte in a sample, the method comprising:

forming a thermal insulation layer over a silicon substrate;

forming a thermal energy source layer over the thermal insulation layer, the thermal energy source layer being a refractory material;

patterning the thermal energy source layer to form a thermal energy source;

forming a thermal conducting layer over the thermal energy source;

forming a temperature sensor over the thermal conducting layer;

forming a working electrode and a counter electrode over the thermal conducting layer;

forming a passivation layer over the temperature sensor; and

patterning the passivation layer to expose at least a portion of the working electrode and counter electrode.

10. The method of claim 9, wherein the refractory material is tantalum aluminum or tantalum nitride.

11. The method of claim 9, wherein the temperature sensor, working electrode, and counter electrode are formed of the same metal.

12. The method of claim 11, wherein the metal is selected from platinum and chromium silicide.

13. A semiconductor device for detecting an analyte in a sample, the semiconductor device including a sensor comprising:

a sensing region formed over a semiconductor substrate, the sensing region including a transducer configured to detect an interaction between the sensing region and the analyte;

an integrated thermal energy source adjacent the sensing region, the integrated thermal energy source configured to produce thermal energy and provide localized heating to the sensing region; and

an integrated temperature sensor adjacent the sensing region, the integrated temperature sensor configured to sense temperature of the sensing region.

14. The semiconductor device of claim 13, wherein the temperature sensor is below the thermal energy source.

15. The semiconductor device of claim 13, wherein the thermal energy source is below the temperature sensor.

16. The semiconductor device of claim 13, wherein the transducer is selected from electrochemical transducers, optical transducers, calorimetric transducers, acoustic transducers, and gravimetric transducers.

17. The semiconductor device of claim 16, wherein the transducer is an electrochemical transducer.

18. The semiconductor device of claim 17, wherein the transducer comprises a working electrode, a counter electrode and the interaction occurs between the analyte, the working electrode and the counter electrode.

19. The semiconductor device of claim 18, wherein the working electrode, counter electrode, and temperature sensor are formed of the same metal.

20. The semiconductor device of claim 13, wherein the thermal energy source and the temperature sensor are below the transducer.