ELECTRO-MECHANICAL MINIATURIZED DEVICE FOR PRESSURE MEASUREMENTS

• US 20160341622A1
• Filed: 01/29/2015
• Published: 11/24/2016
• Est. Priority Date: 01/31/2014
• Status: Active Grant

• Current Assignee: Nanotech Analysis S.R.L.S.
• Original Assignee: Nanotech Analysis S.R.L.S.
• Inventors: MENSA, Gianpiero
• Granted Patent: US 10,578,508 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81B 3/0021 Transducers for transforming electrical into mechanical energy or vice versa dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00
• CPC Class Codes: C07F 9/65586 at least one of the hetero rings does not contain nitrogen as ring hetero atom
• CPC Class Codes: G01L 15/00 Devices or apparatus for measuring two or more fluid pressure values simultaneously
• CPC Class Codes: G01L 27/002 Calibrating, i.e. establishing true relation between transducer output value and value to be measured, zeroing, linearising or span error determination
• CPC Class Codes: G01L 27/007 Malfunction diagnosis, i.e. diagnosing a sensor defect
• CPC Class Codes: G01L 9/0008 using vibrations

Abstract

An electro-mechanical miniaturized device 1 for pressure measurements is described, the device comprising at least one first electro-mechanical miniaturized pressure sensor member 11, configured to detect a respective first pressure value P₁ and to generate a first electrical signal S₁ representative of the first pressure value P₁, and further comprising at least one second electro-mechanical miniaturized pressure sensor member 12, configured to detect a respective second pressure value P₂ and to generate a second electrical signal S₂ representative of said second pressure value P₂. The second sensor member 12 is arranged within a casing 13 suitable to seal it. The device 1 further comprises electronic processing means 10, operatively connected to the first 11 and the second 12 sensor members, and configured to determine a measured pressure value P based on said first S₁ and second S₂ electrical signals; and finally comprises interface means 15, operatively connected to the electronic processing means 10 and configured to provide in output said measured pressure value P. The first 11 and second 12 sensor members, the electronic processing means 10 and the interface means 15 are comprised in a single integrated device.

Claims

1. An electro-mechanical miniaturized device for pressure measurements, comprising:

at least one first electro-mechanical miniaturized pressure sensor member configured to detect a respective first pressure value (P1) and to generate a first electrical signal (S1) representative of said first pressure value (P1);

at least one second electro-mechanical miniaturized pressure sensor member, arranged within a respective casing that is suitable to seal the second sensor member, and configured to detect a respective second pressure value (P2) and to generate a second electrical signal (S2) representative of said second pressure value (P2);

electronic processing means, operatively connected to the first and the second sensor members, configured to determine a measured pressure value (P) based on said first (S1) and second (S2) electrical signals;

interface means, operatively connected to the electronic processing means and configured to provide in output said measured pressure value (P),

wherein said first and second sensor members, electronic processing means, and interface means are comprised in a single integrated device.

2. The device according to claim 1, wherein said first and second sensor members, electronic processing means and interface means are comprised in a single chip of the integrated device.

3. The device according to claim 1, wherein each of said first and second sensor members is configured to have a mechanical or electro-mechanical behaviour, related to at least one respective first or second mechanical or electro-mechanical variable, depending on the pressure or on fluid-dynamics to which it is subjected,

and wherein each of said first (S1) or second (S2) electrical signals is generated based on said at least one respective first or second mechanical or electro-mechanical variable, respectively.

4. The device according to claim 1, wherein each of said first and second sensor members comprises a respective MEMS/NEMS-type oscillating member.

5. The device according to claim 4, wherein each of said MEMS/NEMS-type oscillating members comprises a micro-cantilever, configured to oscillate with a dynamic response that depends on the pressure to which it is subjected.

6. The device according to claim 1, comprising a plurality of second pressure sensor members, to detect a respective plurality of second pressure values (P2), and to generate a respective plurality of second electrical signals (S2) representative of said second pressure values (P2);

and wherein the electronic processing means are further configured to generate the measured pressure value (P) based on a processing of said second electrical signals (S2).

7. The device according to claim 1, wherein said casing is configured to take a closed state, in which it protects the at least one second sensor member against a direct exposure to the surrounding environment, keeping it at a reference pressure coincident with the second pressure value (P2),

wherein the electronic processing means comprise a memory, configured to store characterization data characterizing the second sensor member at the reference pressure (P2),

and wherein the electronic processing means are configured to calibrate the first and the second sensor members based on the second electrical signal (S2) and the stored characterization data.

8. The device according to claim 1, wherein the electronic processing means are configured to process data received by the first and the second sensor members, and to carry out a diagnostic procedure of the first sensor member, based on the received data, so as to identify possible hysteresis phenomena and/or imperfections and/or possible thermal and/or mechanical drifts to which the first sensor member may be subjected.

9. The device according to claim 8, wherein the electronic processing means are configured to carry out, in the case the diagnostic procedure yields a negative outcome, an adjustment and/or compensation and/or optimization procedure of the first sensor member to correct and/or compensate hysteresis phenomena and/or imperfections and/or drifts that are identified based on the results of said diagnostic procedure.

10. The device according to claim 9, further comprising controlled heating means, configured to carry out a degassing and/or a removal of gases adsorbed on surfaces of the micro-cantilever of the first sensor member, under the control of the electronic processing means, and wherein said adjustment procedure of the first sensor member comprises said degassing and/or removal of gases adsorbed on the surface of the micro-cantilever member.

11. The device according to claim 1, further comprising protection thin films, configured to reduce the adsorption of processing gases and to prevent corrosion phenomena, and arranged so as to cover at least the first sensor member,

or further comprising a package comprising micrometer frame filters, arranged so as to cover at least the sensor members comprised in the device.

12. The device according to claim 2, wherein said first and second sensor members and said electronic processing means are arranged on the same side of the chip composing the device,

or wherein said first sensor member is arranged on an opposite side of the chip, with respect to said second sensor member and electronic processing means,

or wherein said first and second sensor members and said electronic processing means are arranged so as to project as a relief, on different planes, with respect to the surface of the chip composing the device.

13. The device according to claim 1, configured to detect pressure values ranging between 10−

4 mbar and 104 mbar.

14. A method for measuring pressure, carried out by an electro-mechanical miniaturized device, the method comprising the steps of:

detecting a first pressure value (P1) and generating a first electrical signal (S1) representative of the first pressure value (P1), by at least one first electro-mechanical miniaturized pressure sensor member of the device;

detecting a second pressure value (P2) and generating a second electrical signal (S2) representative of the second pressure value (P2), by at least one second electro-mechanical miniaturized pressure sensor member of the device, arranged within a respective casing that is suitable to seal it;

determining a measured pressure value (P) based on said first (S1) and second (S2) electrical signals, by electronic processing means of the device;

providing in output the measured pressure value (P), by interface means of the device,

wherein said first and second sensor members, electronic processing means, and interface means are comprised in a single integrated device.

15. The method according to claim 14, further comprising the steps of:

storing, in the electronic processing means, characterization data of the second sensor member, at a reference pressure (P2);

keeping the second sensor member at the reference pressure (P2), within the casing;

calibrating the first sensor member and the second sensor member, by the electronic processing means based on the second electrical signal (S2) and on said characterization data.