TEMPERATURE-MEASURING DEVICE, METHOD FOR MANUFACTURING THE DEVICE, AND SYSTEM FOR MEASURING THE POINT OF IMPACT INCORPORATED IN THE DEVICE

Abstract

A temperature measuring device, a process for manufacturing the device, and a system for measuring an impact point incorporating the device. According to one aspect, a temperature measuring device includes a thin film sheet made of magneto-metallic material such that, in use and the presence of an applied magnetic field, a change of temperature in one region of the sheet generates an electric voltage in the region, the generated electric voltage being readable through means for reading electric voltage corresponding to the region. According to another aspect, there is a process for manufacturing the device. According to yet another aspect, there is a system for measuring an impact point, of radiation or particles, incorporating the device.

Claims

1-25. (canceled)

26. A temperature measuring device comprising: a thin film sheet of magneto-metallic material, the sheet being formed by a plurality of regions and comprising in each of these regions means for reading an electric voltage in the region, the means for reading electric voltage in the region comprising metallic material depositions; so that, in operation and in the presence of an applied magnetic field, a temperature variation in one of the regions generates an electrical voltage in the region, the generated electric voltage being readable through the means for reading electric voltage corresponding to the region.

27. The device, according to claim 26, wherein the sheet has a thickness in the range of 10 nm to 100 nm.

28. The device, according to claim 26, wherein the magneto-metallic material of the sheet is selected from: a semi-metallic and magnetic material; a perovskita-oxide material; a permalloy type alloy; a Ni—Cr alloy; and a metallic ferromagnetic element at room temperature.

29. The device, according to claim 28, wherein the semi-metallic and magnetic material is selected from La.sub.2/3Sr.sub.1/3MnO.sub.3, La.sub.2/3Ca.sub.1/3MnO.sub.3, and Fe.sub.3O.sub.4.

30. The device, according to claim 28, wherein the metallic ferromagnetic element is selected from Fe and Ni.

31. The device, according to claim 26, wherein the metallic material depositions are made of a material selected from platinum, gold, palladium, silver, copper, and aluminum.

32. The device, according to claim 26, further comprising a substrate upon which the thin film sheet of magneto-metallic material is settled.

33. A system for measuring an impact point, comprising: a temperature measuring device according to claim 26; a second sheet made of an absorbing material.

34. The system for measuring the impact point according to claim 33, wherein the impact point is a point of impact of a particle or a radiation beam, and wherein: the second sheet is made of a kinetic energy or a radiation absorbing material configured to transform a kinetic energy of the particle into a temperature variation, or an energy of the radiation beam into heat.

35. A process for manufacturing a temperature measuring device, comprising: providing an aqueous solution comprising precursor cations and a polymer; depositing by a deposition process the aqueous solution on a substrate; subjecting the substrate to a heating process; and generating a plurality of metallic depositions on the substrate.

36. The process according to claim 35, wherein the deposition process is a physical vacuum deposition process.

37. The process according to claim 36, wherein the physical vacuum deposition process is selected from: spin coating; sputtering; atomic layer deposition; and pulsed laser (PLD).

38. The process according to claim 35, wherein generating a plurality of metallic depositions in the substrate comprises: depositing metal on the substrate; applying a mask to the substrate; and applying a lithography process to obtain a plurality of punctual metallic depositions on the substrate.

39. The process according to claim 35, wherein the precursor cations are selected from La, Sr, Ca, Mn, Fe, Cr, and Ni.

40. The process according to claim 35, wherein the substrate is made of magneto-metallic material.

41. The process according to claim 40, wherein the magneto-metallic material is selected from: a semimetallic and magnetic material; a perovskita-oxide material; a permalloy type alloy; a Ni—Cr alloy; and a metallic ferromagnetic element at room temperature

42. The process according to claim 41, wherein the semimetallic and magnetic material is selected from La.sub.2/3Sr.sub.1/3MnO.sub.3, La.sub.2/3Ca.sub.1/3MnO.sub.3, and Fe.sub.3O.sub.4.

43. The process according to claim 41, wherein the metallic ferromagnetic element is selected from Fe and Ni.

44. The process according to claim 40, wherein the subjecting the substrate to a heating process comprises subjecting the substrate to a heating process in which the temperature is set in the range of 600° C. to 900° C.

45. The process according to claim 40, wherein the depositions are made of a material selected from platinum, gold, palladium, silver, copper, and aluminum.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0069] Particular embodiments of the present invention are described by way of non-limiting example, with reference to the accompanying drawings, in which

[0070] FIG. 1 shows examples of temperature measuring devices, according to the present description;

[0071] FIG. 2 shows a graphical representation of the variation of the voltage difference ∇V.sub.xy generated by a thermal gradient as a function of the magnitude of the magnetic field H;

[0072] FIG. 3 shows a graphical representation of the variation of the voltage V generated by a temperature gradient by varying the applied magnetic field H.

DETAILED DESCRIPTION OF THE INVENTION

[0073] As can be seen in FIG. 1, according to some examples, a temperature measuring device 1 may comprise a thin film sheet 2 of magnetic-metallic material. This thin film sheet 2 may be formed of a plurality of regions 3, comprising each of these regions means for reading electric voltage 4 in the region. Thus, when the device 1 is in operation and in the presence of an applied magnetic field, a variation of the temperature in one of the regions 3 generates an electrical voltage (that is, it causes a variation in the electric potential in the region), being this generated electric voltage readable through the means for reading electric voltage corresponding to the region.

[0074] The magnetic-metallic material of the thin film sheet 2 may be selected from: [0075] a semimetallic material; [0076] a perovskita-oxide material; [0077] a permalloy type alloy; [0078] a Ni—Cr alloy; [0079] a metallic ferromagnetic element at room temperature.

[0080] The magnetic semi-metallic material may be selected from La.sub.2/3Sr.sub.1/3MnO.sub.3, La.sub.2/3Ca.sub.1/3MnO.sub.3, Fe.sub.3O.sub.4, whereas the ferromagnetic metal element may be selected from Fe, Ni.

[0081] Furthermore, the thickness of the sheet 2 may be in the range of 10 nm to 100 nm.

[0082] According to some examples, the applied magnetic field may be parallel to the orientation of the device and may have a value greater than 1900 A/m.

[0083] The means for reading electric voltage 4 in the corresponding region may have the configuration of a plurality of electrical contacts (for example two), each of which may be connected to the end of a conductive (e.g. copper) wire. The other end of the wires may be connected to a nanovoltimeter or the like (not shown) in order to measure the voltage variation in the region.

[0084] Basically, FIG. 1 further shows the operation of the temperature measuring device 1 when forming part of a system for determining the impact point of a radiation beam or a particle, in which it is used a sheet 5 which transforms the kinetic energy of a particle in a temperature variation (in this case it may be a sheet of kinetic energy absorbing material) or the energy of radiation beam in heat (in this case it may be a sheet of radiation absorbing material), producing a gradient or a temperature variation 6. This temperature gradient 6 in the presence of a magnetic field 7 generates a voltage 8 which is measured and which allows to determine the point of impact of the radiation or the particle.

[0085] In some examples, a 35 nm thick layer of ferromagnetic and metallic oxide La.sub.2/3Sr.sub.1/3MnO.sub.3 (LSMO) is deposited with side dimensions of 5 mm×5 mm. This layer is deposited by pulsed laser deposition (PLD) on a 0.5 mm thick monocrystalline SrTiO.sub.3 (STO) substrate.

[0086] At one end of the LSMO film, a Pt line 4 mm long, 100 microns wide and 10 nm thick is deposited by evaporation. To determine or measure the voltage generated in response to the generation of a thermal gradient, the ends of the platinum line are connected by copper wires to a nanovoltimeter to determine the voltage variation, as described above.

[0087] The STO with the LSMO layer at its top is placed on a copper block with a ceramic electrical resistance inside it, which is used to vary the temperature and thus create a thermal gradient between the bottom and top of the LSMO film. In addition, the system is subjected to vacuum to a base pressure of 10−5 Torr, to avoid uncontrolled thermal gradients that can cause parasitic gradients which would contaminate the measurement.

[0088] A current is applied to the resistor in the copper block in order to increase the temperature of the base and create a thermal gradient through the LSMO film. When very small power is dissipated (a few mW), a GaAs diode stuck to the copper base is not able to detect any variation of the temperature. However, as can be seen in FIG. 3, performing a magnetic field scanning a transverse voltage between the ends of the platinum strip, due to the Anomalous Nernst Effect (ANE), appears. This voltage changes sign when changing the magnetic field, as expected according to the ANE equation. Once the saturation magnetization of the LSMO system is reached, the read voltage is stable with the field. In addition, the voltage increases linearly with the thermal gradient through the LSMO layer. For the example shown, the estimated temperature variation is 2 micro Kelvin between the top and bottom of the 35 nm LSMO layer.

[0089] For reasons of completeness, various aspects of the present disclosure are set out in the following numbered clauses: [0090] Clause 1. A temperature measuring device comprising: [0091] a thin film sheet of magneto-metallic material, being formed this sheet by a plurality of regions and comprising each of these regions means for reading electric voltage in the region, comprising this means metallic material depositions;
so that, in operation and in the presence of an applied magnetic field, a temperature variation in one of the regions generates an electric voltage in the region, being readable this generated electric voltage through the means for reading electric voltage corresponding to the region. [0092] Clause 2. The device, according to clause 1, wherein the sheet has a thickness comprised in the range 10 nm to 100 nm. [0093] Clause 3. The device, according to clause 1, wherein the magneto-metallic material of the sheet is selected from: [0094] a semi-metallic and magnetic material; [0095] a perovskita-oxide material; [0096] a permalloy type alloy; [0097] a Ni—Cr alloy; [0098] a metallic ferromagnetic element at room temperature. [0099] Clause 4. The device, according to clause 3, wherein the semi-metallic and magnetic material is selected from La.sub.2/3Sr.sub.1/3MnO.sub.3, La.sub.2/3Ca.sub.1/3MnO.sub.3, Fe.sub.3O.sub.4. [0100] Clause 5. The device, according to clause 3, wherein the metallic ferromagnetic element is selected from Fe, Ni. [0101] Clause 6. The device, according to clause 1, wherein the depositions are made of a material selected from platinum, gold, palladium, silver, cupper, aluminum. [0102] Clause 7. The device, according to clause 1, wherein the depositions are punctual depositions. [0103] Clause 8. The device, according to clause 6, wherein the separation between depositions of the same region is in the range from microns to millimeters. [0104] Clause 9. The device, according to clause 1, wherein also comprises a substrate on which the thin film sheet of magneto-metallic material is settled. [0105] Clause 10. A system for measuring an impact point comprising: [0106] a temperature measuring device according to clause 1; [0107] a sheet made of an absorbing material. [0108] Clause 11. The system for measuring the impact point according to clause 10, wherein the impact point is of a particle or a radiation beam, and wherein: [0109] the sheet is made of a kinetic energy or a radiation absorbing material, configured to transform such kinetic energy into a temperature variation or radiation beam energy into heat. [0110] Clause 12. A process for manufacturing a temperature measuring device wherein it comprises: [0111] providing an aqueous solution comprising precursor cations and a polymer; [0112] depositing by a deposition process the aqueous solution on a substrate; [0113] subjecting the substrate to a heating process; [0114] generating a plurality of metal depositions on the substrate. [0115] Clause 13. The process, according to clause 12, wherein the deposition process is a physical vacuum deposition process. [0116] Clause 14. The process, according to clause 13, wherein the physical vacuum deposition process is selected from: [0117] spin coating; [0118] sputtering; [0119] atomic layer deposition; [0120] pulsed laser (PLD). [0121] Clause 15. The process, according to clause 12, wherein generating a plurality of metallic depositions in the substrate comprises: [0122] depositing metal on the substrate; [0123] applying a mask to the substrate; [0124] applying a lithography process to obtain a plurality of punctual metallic depositions on the substrate [0125] Clause 16. The process, according to clause 12, wherein the precursor cations are selected from La, Sr, Ca, Mn, Fe, Cr, Ni. [0126] Clause 17. The process, according to clause 12, wherein the polymer is selected from water soluble polymers of PEI (polyethyleneimine) or chitosan type. [0127] Clause 18. The process, according to clause 12, wherein the cation concentration is in the millimolar range. [0128] Clause 19. The process, according to clause 12, wherein the polymer concentration is in the millimolar range. [0129] Clause 20. The process, according to clause 12, wherein the substrate is made of magneto-metallic material. [0130] Clause 21. The process, according to clause 20, wherein the magneto-metallic material is selected from: [0131] a semimetallic and magnetic material; [0132] a perovskita-oxide material; [0133] a permalloy type alloy; [0134] a Ni—Cr alloy; [0135] a metallic ferromagnetic element at room temperature [0136] Clause 22. The process, according to clause 21, wherein the semimetallic and magnetic material is selected from La.sub.2/3Sr.sub.1/3MnO.sub.3, La.sub.2/3Ca.sub.1/3MnO.sub.3, Fe.sub.3O.sub.4. [0137] Clause 23. The process, according to clause 21, wherein the metallic ferromagnetic element is selected from Fe, Ni. [0138] Clause 24. The process, according to clause 12, wherein subjecting the substrate to a heating process comprises subjecting the substrate to a heating process in which the temperature is set in the range of 600° C. to 900° C. [0139] Clause 25. The process, according to clause 12, wherein the depositions are made of a material selected from platinum, gold, palladium, silver, cupper, aluminum.

[0140] Although only some particular embodiments and examples have been described here, one skilled in the art will appreciate that other alternative embodiments and/or uses are possible, as well as obvious modifications and equivalent elements. In addition, the present disclosure encompasses all possible combinations of the particular embodiments which have been described. Numerical signs relating to the drawings and placed in parentheses in a claim are only intended to increase the understanding of the claim, and should not be construed as limiting the scope of the protection of the claim. The scope of the present disclosure should not be limited to particular embodiments, but should be determined only by an appropriate reading of the appended claims.