The invention relates to a method for producing an electrical component, in particular, for producing an electrical component having a temperature-dependent resistance characteristic. The invention furthermore relates to an electrical component, in particular an electrical component having a temperature-dependent resistance characteristic.
Electrical components having a temperature-dependent resistance behavior can be used for measuring temperatures. In the case of NTC components, the electrical resistance decreases, for example, as the temperature rises. Such electrical components comprise a material whose resistance value is dependent on the ambient temperature. The temperature-sensitive resistance material is usually arranged in a housing of the component, for example, an SMD housing. In order to measure a temperature of a body, the components are usually arranged by their housing on the surface of the body.
The disadvantage of such an arrangement is that the thermal coupling of the material having the temperature-dependent resistance characteristic to the body whose temperature is intended to be determined is not optimal on account of the surrounding housing of the component. By way of example, an air gap is present between the temperature-sensitive material and the housing of the component, said air gap influencing the heat transfer from the surface of the body to the temperature-sensitive material and ultimately corrupting the temperature measurement.
Embodiments provide a method for producing an electrical component in which the coupling of a material that is temperature-sensitive with regard to its resistance to a surface of a body whose temperature is intended to be determined is improved. Furthermore, embodiments provide an electrical component in which the coupling of the material that is temperature-sensitive with respect to its resistance to the surface of a body whose temperature is intended to be determined is improved.
Embodiments provide a carrier element and a material having a temperature-dependent resistance. The material is arranged on a surface of the carrier element for producing a resistance layer. For linking the resistance layer to the carrier element, the resistance layer is subsequently sintered.
If the surface temperature of a body, for example, the surface temperature of a container, is intended to be measured, it is necessary for an electrical insulation to be present between the body and the temperature-dependent resistance layer of the component. Furthermore, a good thermal conductivity ought to be present between the surface of the body whose temperature is intended to be measured and the temperature-sensitive material of the resistance layer. Therefore, a non-electrically conductive material is preferably used for the carrier element. An electrically conductive ceramic, for example, an NTC thermistor material in the case of an NTC component, can be used for the resistance layer.
By combining a non-electrically conductive carrier material with an electrically conductive ceramic, the specified method provides a novel method for producing temperature-sensitive electrical components which can be used to fabricate components whose resistance layer can be coupled well to a support via the carrier element.
A non-sintered material is preferably used for the resistance layer. By way of example, a calcined metal oxide powder can be used. A screen-printable ceramic paste is produced from this starting material. The paste can be applied onto the carrier element in the form of arbitrary structures. The structures can be printed, for example, onto the material of the carrier element. At the time of printing, the temperature-sensitive material of the resistance layer does not yet have its final properties. The material assumes the final properties only after the sintering process.
The stability of such an arrangement composed of a non-sintered material having a temperature-dependent resistance and a carrier element to which the material is fixedly linked by a sintering process only after the printing of the paste has a significantly higher stability than if pastes, in particular sintered pastes, were used which already had their final properties upon being applied onto the carrier element. By printing the material having the temperature-dependent resistance onto the carrier element, it is possible realize complex resistance structures. Furthermore, the method affords the advantage of miniaturization.
By means of the specified production method, it is thus possible to realize a temperature sensor element whose sensitive ceramic layer is fixedly linked to the electrically nonconductive, but thermally highly conductive material of the carrier element by means of a sintering process. It is thus possible to satisfy the requirements of temperature measuring applications in which a temperature sensor element is coupled via planar surfaces, wherein a maximum thermal coupling is affected and the thermal mass can be minimized.
One embodiment of such an electrical component is specified in patent claim 11. The electrical component comprises a carrier element and a resistance layer composed of a material having a temperature-dependent resistance. The resistance layer is arranged on a surface of the carrier element and is linked to the carrier element by a sintering process.
Further embodiments of the method for producing the electrical component and of the electrical component can be gathered from the dependent claims.
The invention is explained in greater detail below with reference to figures showing exemplary embodiments of the method for producing the electrical component and embodiments of the electrical component. In the figures:
In a method step A, firstly a carrier element 10 is provided. In a method step B, a material having a temperature-dependent resistance is furthermore provided. In a method step C, the material is applied on a surface O10 of the carrier element 10 for producing a resistance layer 20 on the carrier element. Afterward, in a method step D, the resistance layer 20 is sintered for linking the resistance layer 20 to the carrier element 10. In a method step E, electrodes 30a, 30b are applied to the electrical component produced until then, for applying a voltage to the resistance layer 20 of the component. At least one of the electrodes 30a and 30b can be arranged on a surface O20 of the resistance layer 20 or on a further surface U10 of the carrier element 10.
For applying a voltage to the resistance layer 20, the temperature-sensitive electrical component in
In method step A, the carrier element 10 is preferably provided from a non-electrically conductive material. The carrier layer 10 of the electrical component shown in
In method step A, the carrier element 10 can be provided, for example, from a material composed of aluminum oxide or aluminum nitride or combinations thereof. In a manner corresponding to method step A, the electrical component shown in
In method step B, the material of the resistance layer 20 is provided before applying the resistance layer on the carrier element 10, for example, as a material which is not sintered. The material of the resistance layer 20 can be provided as a calcined metal oxide which is not sintered. In particular, in method step B, the resistance layer 20 can be provided from a material composed of nickel oxide, manganese oxide, copper oxide, zinc oxide or composed of combinations thereof.
In a manner corresponding to method step B, the temperature-sensitive electrical component 1 shown in
In accordance with one possible embodiment of the method, firstly, in method step B, before applying the resistance layer 20 onto the carrier element 10, the material of the resistance layer 20 can be provided as a screen-printable ceramic paste which is not yet sintered and therefore does not yet have its final properties. In the subsequent method step C, before the actual sintering of the resistance layer 20, a structure of the resistance layer 20 can be printed onto the carrier element 10. The structure of the resistance layer 20 can be printed onto the carrier element 10 by means of a screen printing method, in particular, before the resistance layer is sintered and thereby fixedly linked to the carrier element.
The printable paste can be embodied as a metal oxide-ceramic powder mixture having an NTC characteristic. Since the paste is not yet sintered when it is applied onto the carrier element, the material of the resistance layer 20 does not yet have its final properties at the time of printing, and it assumes said final properties only after the sintering process. The stability of the temperature-sensitive electrical component is therefore higher than if pastes were used which already had their final properties upon being applied onto the carrier element 10, for example, pastes containing a sintered material. The production of the screen-printable ceramic paste makes it possible to print arbitrary structures onto the material of the carrier element 10 and to link them thermally and mechanically to the material of the carrier element 10.
Owing to the use of the carrier element as a substrate onto which the temperature-dependent resistance layer is applied, the temperature-sensitive electrical component has a high mechanical stability. Furthermore, the electrical component has a high thermal conductivity and at the same time ensures an electrical insulation between the material of the resistance layer 20 and a support onto which the carrier element 10 is applied.
In the embodiment of the electrical component as shown in
Number | Date | Country | Kind |
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10 2015 110 607.8 | Jul 2015 | DE | national |
This patent application is a national phase filing under section 371 of PCT/EP2016/065038, filed Jun. 28, 2016, which claims the priority of German patent application 10 2015 110 607.8, filed Jul. 1, 2015, each of which is incorporated herein by reference in its entirety.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2016/065038 | 6/28/2016 | WO | 00 |