Micromachined thermistor

Patent metadata

Field	Value
Publication number	US-9945734-B1
Application number	US-201715601431-A
Country	US
Kind code	B1
Filing date	May 22, 2017
Priority date	Sep 9, 2011
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

A micromachined apparatus includes micromachined thermistor having first and second ends physically and thermally coupled to a substrate via first and second anchor structures to enable a temperature-dependent resistance of the micromachined thermistor to vary according to a time-varying temperature of the substrate. The micromachined thermistor has a length, from the first end to the second end, greater than a linear distance between the first and second anchor structures.

First claim

What is claimed is:

1. A micromachined apparatus comprising:
a substrate having first and second anchor structures; and
a micromachined thermistor having (i) first and second ends physically and thermally coupled to the substrate via the first and second anchor structures, respectively, to enable a temperature-dependent resistance of the micromachined thermistor to vary according to a time-varying temperature of the substrate, and (ii) a length, from the first end to the second end, greater than a linear distance between the first and second anchor structures.

2. The micromachined apparatus of claim 1 wherein the micromachined thermistor comprises a loop shape.

3. The micromachined thermistor of claim 1 wherein the micromachined thermistor comprises a beam that extends, from the first anchor structure to the second anchor structure, along a path that deviates from an axis between the first and second anchor structures.

4. The micromachined apparatus of claim 1 further comprising an encapsulation structure secured to the substrate and forming a cavity in which the micromachined thermistor is disposed.

5. The micromachined apparatus of claim 4 wherein the encapsulation structure forms a vacuum cavity in which the micromachined thermistor is disposed.

6. The micromachined apparatus of claim 1 further comprising measurement circuitry, electrically coupled to the micromachined thermistor, to generate information indicative of temperature based at least in part on the temperature-dependent resistance of the micromachined thermistor.

7. The micromachined apparatus of claim 6 wherein the measurement circuitry is electrically coupled to the micromachined thermistor via the first and second anchor structures.

8. The micromachined apparatus of claim 1 further comprising a microelectromechanical structure thermally coupled to the micromachined thermistor via the substrate such that the time-varying temperature of the substrate and temperature-dependent resistance of the micromachined thermistor is indicative of a time-varying temperature of the microelectromechanical structure.

9. The micromachined apparatus of claim 8 wherein the microelectromechanical structure is anchored to the substrate by at least one of the first and second anchor structures and thermally coupled to the micromachined thermistor via the substrate by virtue of sharing the at least one of the first and second anchor structures with the micromachined thermistor.

10. The micromachined apparatus of claim 8 further comprising circuitry electrically coupled to the micromachined thermistor and microelectromechanical structure, the circuitry including (i) measurement circuitry to generate temperature information based at least in part on the temperature-dependent resistance of the micromachined thermistor and (ii) output-generating circuitry to generate an output signal in accordance with a signal indicative of mechanical motion of the microelectromechanical structure and dependent, at least in part, on the temperature information.

Assignees

• Sitime Corp

Inventors

• Arft Carl
• Partridge Aaron
• Hagelin Paul M

Classifications

• H03L1/00

  Stabilisation of generator output against variations of physical values, e.g. power supply · CPC title

• G01K13/02

  for measuring temperature of moving fluids or granular materials capable of flow · CPC title

• G01K7/226 Primary

  using microstructures, e.g. silicon spreading resistance · CPC title