Thin-film element with a positive resistance coefficient

Abstract

Thin-film element with positive resistance coefficient (100, 100a), comprising: a substrate plate (110); a thin-film circuit (120) provided on the aforementioned substrate plate (110) and comprising two circuit solder pads (122); and two conductors (130) cut from a conductor frame (24) and comprising two front-end solder pads (132), wherein the two aforementioned front-end solder pads (132) are each soldered to the two aforementioned circuit solder pads (122), wherein the two aforementioned conductors (130) extend outside the aforementioned substrate plate (110) and wherein the thickness of each of the two aforementioned front-end solder pads (132) is identical to the thickness of the part extending outside the aforementioned substrate plate (110).

Description

Technical field

[0001] The present application relates to an element, in particular an element in thin-film form with a positive resistance coefficient. State of the art

[0002] Electronic components are increasingly used in various industrial sectors, such as temperature measurement, overheating protection for motors, temperature control for electric vehicle batteries, overheating protection for high-speed train drive motors, overheating protection for AI servers, etc. Application temperatures are also increasing, from typical operating temperatures of up to 85 °C to approximately 600-700 °C. Conventional thermal resistance thermocouples (NTCs, negative temperature coefficient thermocouples) for temperature measurement are no longer sufficient for these applications, and other thermocouples with resistance wires made of metal alloys are gradually being replaced by thin-film thermocouples with a positive temperature coefficient thermocouple (PTC) due to the enormous increase in precious metal prices.

[0003] Thin-film elements with a positive resistance coefficient can be used in internationally interchangeable circuits due to their stable resistance coefficient (TCR). The specifications of thin films from different manufacturers are interchangeable, which significantly increases their market acceptance, with platinum metal thin-film elements with a positive resistance coefficient being the most popular. The physical and chemical stability of platinum is optimal, and the corresponding stable resistance coefficient (TCR) remains unchanged over a lifetime of 20-30 years without being affected by oxidation with acids, bases, or corrosive gases.Platinum costs approximately one-third the price of gold, making platinum thin-film resistors widely used in industrial development, particularly for temperature control in AI heat dissipation modules, due to their stability. The demand for platinum temperature sensors is expected to increase dramatically, especially due to their use in immersion cooling of AI servers with high heat dissipation requirements, representing enormous market potential. Currently, over 170 million units are deployed annually, dominating the market for positive resistivity (PTC) temperature measurement and control elements.

[0004] To meet the requirements for electrical insulation and high-temperature applications, thin-film elements with a positive resistance coefficient and platinum as the thin film must have this thin film applied to an insulating ceramic substrate. Simultaneously, the ceramic substrate must be resistant to the corrosive effects of corrosive gases during the manufacturing process. Furthermore, the commonly used surface-mount (SMT) pads are not suitable for high temperatures such as 600–700 °C. Therefore, high-temperature-resistant conductors, such as nickel wire, palladium wire, or platinum-coated nickel wire, are used for the conductors of thin-film elements with a positive resistance coefficient to prevent oxidation and degradation during high-temperature use.

[0005] Because the conductors and the thin-film circuit are located on the same side of the ceramic substrate plate, the connection between the conductors and the thin-film circuit can only be established using a parallel gate welding technique. The positive and negative electrode heads of the parallel electrodes are located on the same side of the conductors, and the power supply delivers high current and high voltage to melt and solder the conductors and the thin-film metal pad together. The soldering process typically takes only a few microseconds, allowing the conductors, with a melting point above 1200 °C, to melt instantly and be connected to the solder pad (made of gold) to form a continuous circuit.

[0006] Because the dimensions of the conductors are up to ten times those of the solder pads, human error (inaccurate focusing, imprecise alignment, insufficient soldering time, etc.) leads to problems such as cold soldering and soldering failures, meaning the quality of manually manufactured products cannot be guaranteed. The reliability of current thin-film elements with a positive resistance coefficient is relatively low. Particularly when used for automotive temperature measurement and battery overheating protection, vibrations from electric vehicles during continuous driving can easily cause manually manufactured parallel electrode solder pads to fail and become disconnected, resulting in significant losses.

[0007] Even more serious, however, is the fact that automating the parallel electrode soldering technique is virtually impossible. In practice, the soldering and alignment processes cannot be automated. Technicians must switch on the power supply after focusing under the microscope and apply a high current continuously for several milliseconds. For example, in parallel electrode soldering, a solder pad can be soldered with 0.7V, 135A, and a total power of 95W for 6 milliseconds, or a solder pad can be soldered with 0.6V, 282.3A, and a total power of 170W for 6 milliseconds. These two examples illustrate that parallel electrode soldering requires experienced technicians with excellent eyesight.

[0008] Therefore, research in this field focuses on how to simplify the production of thin-film elements with a positive resistance coefficient, how to reduce manufacturing costs, and how to increase quality and reliability. Subject of the utility model

[0009] The present application provides for the provision of a thin-film element with a positive resistance coefficient, which offers an optimal quality rate and reliability, while being easy to manufacture.

[0010] The present application provides a manufacturing process for the element in thin-film form with a positive resistance coefficient, with which the described element can be produced in thin-film form with a positive resistance coefficient.

[0011] The thin-film element with a positive resistance coefficient according to the present application comprises a substrate plate, a thin-film circuit, and two conductors. The thin-film circuit is provided on the substrate plate and comprises two circuit solder pads, wherein the two conductors are cut from a conductor frame and comprise two front-end solder pads, each of which is soldered to the two circuit solder pads, the two conductors extending outside the substrate plate, and the thickness of each of the two front-end solder pads being identical to the thickness of the portion extending outside the substrate plate.

[0012] In an exemplary embodiment of the present application, it is provided that the thickness of each of the two conductors mentioned is between 0.05 millimeters and 4 millimeters.

[0013] In an exemplary embodiment of the present application, it is provided that the thickness of each of the two conductors mentioned is between 0.1 millimeters and 0.2 millimeters.

[0014] In an exemplary embodiment of the present application, it is provided that the two said front-end solder pads are each soldered to the two said circuit solder pads by means of two solder plates, wherein the material of each of the two said solder plates comprises a nickel alloy.

[0015] In an exemplary embodiment of the present application, it is provided that the material of each of the two solder plates mentioned comprises a nickel-phosphorus alloy, nickel-silicon alloy, nickel-copper alloy, nickel-zinc alloy, nickel-copper-silicon alloy or nickel-titanium alloy.

[0016] In an exemplary embodiment of the present application, it is provided that the thickness of the soldering plate is between 0.1 micrometers and 50 micrometers.

[0017] In an exemplary embodiment of the present application, it is provided that the substrate plate comprises a first surface and a second surface opposite each other, wherein the two circuit solder pads are located on the first surface, and wherein each of the two conductors also comprises a clamping section located at its front end, the front-end solder pad being provided on the first surface of the substrate plate, while the clamping section clamps the second surface of the substrate plate.

[0018] In an exemplary embodiment of the present application, it is provided that the two conductors mentioned comprise two opposing, concave surfaces.

[0019] In an exemplary embodiment of the present application, it is provided that the material of said conductor comprises nickel metal or a nickel alloy.

[0020] Manufacturing method for a thin-film element with a positive resistance coefficient according to the present application, comprising: providing a substrate plate having several thin-film circuits, wherein the thin-film circuits are arranged in a series and wherein the thin-film circuits each comprise several circuit solder pads; Performing the forming process of the conductor frame to form a conductor frame board material into a conductor frame, wherein the conductor frame comprises multiple conductors and a connecting section linking the conductors, each conductor comprising multiple front-end solder pads located away from the connecting section; aligning the conductor frames onto the substrate board such that the front-end solder pads of the conductor frames are aligned with the circuit solder pads of the thin-film circuits; soldering the front-end solder pads of the conductor frames to the circuit solder pads of the thin-film circuits; cutting the substrate board and the connecting section to form the single thin-film element with a positive resistance coefficient, wherein the thin-film element with a positive resistance coefficient comprises the corresponding thin-film circuit and two of the conductors.

[0021] In an exemplary embodiment of the present application, prior to the aforementioned step of carrying out the forming process of the conductor frame, the following is further included: providing solder plate material on the conductor frame plate material, wherein the step of carrying out the forming process of the conductor frame further includes: jointly forming the solder plate material and the conductor frame plate material and forming several solder pads on the front-end solder pads.

[0022] In an exemplary embodiment of the present application, the said step of carrying out the forming process of the conductor frame further comprises: punching the conductor frame plate material to form the conductors and a connecting section, wherein each of the conductors comprises a front-end solder pad and a bending section located away from the connecting section; and bending the bending section to form a clamping section, wherein the clamping section and the front-end solder pad are located on different planes.

[0023] In an exemplary embodiment of the present application, in the aforementioned step of aligning the conductor frames onto the substrate plate, the substrate plate comprises a first surface and a second surface opposite each other, wherein the two circuit solder pads are located on the first surface, wherein the front-end solder pad is provided on the first surface of the substrate plate, while the clamping section clamps the second surface of the substrate plate.

[0024] Based on the above explanations, the two conductors of the thin-film element with a positive resistance coefficient according to the present application are cut from the conductor frame such that the thickness of the front-end solder pad is identical to the thickness of the portion of the respective conductor extending outside the substrate plate. Manufacturing the thin-film element with a positive resistance coefficient according to the present application requires only aligning the conductor frame with the substrate plate. After aligning the front-end solder pads of the conductor frame with the circuit solder pads of the thin-film circuits, the described thin-film element with a positive resistance coefficient is obtained by soldering and cutting. In contrast to the known state of the art, which requires individual soldering of the solder pads by technicians, the thin-film element with a positive resistance coefficient according to the present application allows for mass production, resulting in an effective saving of working time and effort. Explanation of the figures Fig. Figure 1 shows a three-dimensional schematic view of the element in thin-film form with a positive resistance coefficient according to an exemplary embodiment of the present application. Fig. Figure 2 shows a schematic representation of the manufacturing process for the element in thin-film form with a positive resistance coefficient according to an exemplary embodiment of the present application. Fig. Figure 3 shows a three-dimensional schematic view of the unpunched conductor frame board material. Fig. Figure 4 shows a three-dimensional schematic view of the conductor frame not aligned with the substrate plate. Fig. Figure 5 shows a schematic side view of the guide frame located above the substrate plate. Fig. Figure 6 shows a schematic view of the aligned conductor frame connected to the substrate plate. Fig. 2. Fig. Figure 7 shows a three-dimensional schematic view of the element in thin-film form with a positive resistance coefficient according to a further exemplary embodiment of the present application, wherein the conductor frame is partially bent to clamp the second surface of the substrate plate. Fig. Figure 8 shows a three-dimensional schematic view of the unpunched conductor frame board material. Fig. Figure 9 shows a three-dimensional schematic view of the conductor made of Fig. 8 after punching and bending. Exemplary embodiments

[0025] The following is a description of the element in thin-film form with a positive resistance coefficient, which can be manufactured simply and with a comparatively optimal quality rate without using the parallel electrode soldering technique according to the state of the art.

[0026] Fig. Figure 1 shows a three-dimensional schematic view of the element in thin-film form with a positive resistance coefficient according to an exemplary embodiment of the present application. As can be seen from Fig. As shown in Figure 1 for reference, the thin-film element with a positive resistance coefficient 100 in the present exemplary embodiment comprises a substrate plate 110, a thin-film circuit 120, and two conductors 130. The thin-film circuit 120 is provided on the substrate plate 110 and comprises two circuit solder pads 122. The material of the thin-film circuit 120 is, for example, platinum, although no such restriction is specified.

[0027] In the present exemplary embodiment, the two conductors 130 are made from a conductor frame 24 ( Fig. 4) cut. The two conductors 130 comprise two front-end solder pads 132, each of which is soldered to the two circuit solder pads 122. The two conductors 130 extend outside the substrate plate 110 and comprise two opposing, convex surfaces 136, the design of which reduces the probability of conduction by the two conductors 130 due to the relatively small distance between them.

[0028] Because in the present exemplary embodiment the two conductors 130 are cut from a conductor frame 24, mass production of the element in thin-film form with a positive resistance coefficient 100 is possible in this exemplary embodiment compared to the known prior art which requires individual soldering of the solder pads by technicians. This results in an effective saving of working time and effort. The manufacturing process for the element in thin-film form with a positive resistance coefficient 100 is described below.

[0029] Fig. Figure 2 shows a schematic representation of the manufacturing process for the element in thin-film form with a positive resistance coefficient according to an exemplary embodiment of the present application. As shown in Figure 2, the manufacturing process for the element in thin-film form with a positive resistance coefficient is shown in Figure 2. Fig. As shown in Figure 2 for reference, the manufacturing process 200 for the thin-film element with a positive resistance coefficient 100 in the present exemplary embodiment comprises the following steps: First, in step 210, a substrate plate 110 having several thin-film circuits 120 (of a construction as shown on the left in Figure 2) is provided. Fig. 4 shown), wherein the thin-film circuits 120 are arranged in a series and wherein each thin-film circuit 120 comprises several circuit solder pads 122. Specifically, in the present exemplary embodiment, the thin-film circuits 120 are produced on the substrate plate 110 and each thin-film circuit 120 comprises two circuit solder pads 122.

[0030] Fig. Figure 3 shows a three-dimensional schematic view of the unpunched conductor frame board material.

[0031] Fig. Figure 4 shows a three-dimensional schematic view of the conductor frame not aligned with the substrate plate.

[0032] Fig. Figure 5 shows a schematic side view of the guide frame located above the substrate plate. As shown in the diagram... Fig. 2, Fig. 3 and Fig. As shown in step 5 as a reference, the execution of step 220 then follows. Fig. 2 by carrying out the forming process of the conductor frame, wherein a conductor frame plate material 20 ( Fig. 3) to a ladder frame 24 ( Fig. 4) is formed.

[0033] As in Fig. As shown in Figure 3, in the present exemplary embodiment, the conductor frame plate material 20 consists of plate material from a complete plate, which is placed on the lower die 10, wherein the lower die 10 comprises several die holes 12, wherein the conductor frame plate material 20, after being transported over the die holes 12, is punched downwards through the upper die to create the Fig. The 4 shown guide frame 24 is formed. The punched guide frame 24 emerges through the through-opening 14.

[0034] As in Fig. As shown in Figure 4, the conductor frame 24 comprises several conductors 130 and a connecting section 22 connecting the conductors 130. Each conductor 130 comprises several front-end solder pads 132 located away from the connecting section 22.

[0035] Because the conductors 130 are cut from the conductor frame 24 in the present exemplary embodiment, the conductors 130, as shown in Fig. Figure 5 shows a flat cross-section compared to the circular cross-section of the known prior art. The thickness of each of the two front-end solder pads 132 is identical to the thickness of the portion extending outside the substrate plate 110.

[0036] In one exemplary embodiment, the thickness of each of the two conductors 130 is between 0.05 millimeters and 4 millimeters. In another exemplary embodiment, the thickness of each of the two conductors 130 is between 0.15 millimeters and 0.35 millimeters. In another exemplary embodiment, the thickness of each of the two conductors 130 is between 0.1 millimeters and 0.2 millimeters. Furthermore, in the present exemplary embodiment, the material of the conductors 130 comprises nickel metal or a nickel alloy.

[0037] It should be noted, however, that in the present exemplary embodiment, before the execution of step 220 of carrying out the forming process of the conductor frame, the following is further included: step 215, as in Fig. Figure 3 shows the provision of a solder plate material 30 on the circuit board material 20. The solder plate material 30 is attached to the circuit board material 20, for example, by gluing.

[0038] In the present exemplary embodiment, step 220 of carrying out the forming process of the conductor frame 24 further includes: step 222, forming the solder plate material 30 together with the conductor frame plate material 20 and forming several solder plates 140 ( Fig. 5) on the front-end solder pads 132. In other words, this means that a corresponding solder plate 140 is provided on each front-end solder pad 132, the front-end solder pads 132 having a shape identical to the solder plates 140.

[0039] In the present exemplary embodiment, solder plates 140 are used to replace the gold paste known from the prior art. With conventional thin-film elements with a positive resistance coefficient, expensive gold paste must be printed onto the thin-film circuit using steel plate printing to enable the soldering of subsequent conductors, resulting in a complicated and costly manufacturing process. In the present exemplary embodiment, solder plates 140 are used to replace the gold paste, with the conductor frame 24 being manufactured using a combined stamping and forming process.The solder pads 140 are formed on the front-end solder pads 132, whereby this design provides the compressive stress required for brazing, thereby not only resulting in a huge reduction in the cost of the solder material, but also enabling the use of the compressive stress for brazing, which improves the adhesion of the front-end solder pads 132.

[0040] In one exemplary embodiment, the material of the solder plate 140 consists mainly of a base metal or a base metal alloy, thereby significantly reducing material costs. The material of each of the two solder plates 140 can comprise a nickel alloy. Specifically, the material of each of the two solder plates 140 can comprise a nickel-phosphorus alloy, a nickel-silicon alloy, a nickel-copper alloy, a nickel-zinc alloy, a nickel-copper-silicon alloy, or a nickel-titanium alloy.

[0041] In one exemplary embodiment, the thickness of the solder plates 140 is between 0.1 micrometers and 50 micrometers. In a particularly advantageous exemplary embodiment, the thickness of the solder plates 140 is between 2 micrometers and 10 micrometers.

[0042] It is understood that in further exemplary embodiments the element in thin-film form with a positive resistance coefficient 100 can also be printed onto the thin-film circuit 120 using zinc paste or gold paste by steel plate printing, so that there is no limitation with regard to the embodiments shown in the figures.

[0043] Fig. Figure 6 shows a schematic view of the aligned conductor frame connected to the substrate plate. Fig. 2. As from Fig. 2, Fig. 5 and Fig. As shown in Figure 6 as a reference, step 230 is then carried out by aligning the conductor frames 24 onto the substrate plate 110, so that the front-end solder pads 132 of the conductor frames 24 are each aligned with the circuit solder pads 122 of the thin-film circuits 120. Step 240 is then carried out by soldering the front-end solder pads 132 of the conductor frames 24 to the circuit solder pads 122 of the thin-film circuits 120. In an exemplary embodiment, the two front-end solder pads 132 are each soldered to the two circuit solder pads 122 by means of two solder plates 140.

[0044] Finally, in step 250, the substrate plate 110 and the connecting section 22 are cut to produce the individual element in thin-film form with a positive resistance coefficient 100 (as in Fig. 1 shown) to form, wherein the thin-film element with positive resistance coefficient 100 comprises the corresponding thin-film circuit 120 and two of the conductors 130.

[0045] The conductors 130 of the thin-film element with a positive resistance coefficient 100 according to the present exemplary embodiment are manufactured using a technique involving a conductor frame 24. Based on the dimensions of the thin-film element with a positive resistance coefficient 100 and the size and spacing of the circuit solder pads 122, a series of conductors 130 is produced. The solder material can be applied to the circuit solder pads 122 by steel plate printing or attached (glued) to the conductor frame plate material 20 using solder plate material 30, whereby the conductor frame 24, comprising several solder plates 140, is formed by a common stamping process.The front-end solder pads 132 of the circuit frame 24 (together with the solder plates 140) are attached to the circuit solder pads 122 of the uncut substrate plate 110 using an alignment tool (not shown) and then soldered. After reflow soldering or brazing (hard soldering) with pressure applied to an alignment mold, the temperature is reduced and the assembly is demolded, so that a structure with a significantly increased solder joint strength can be formed. The soldering temperature must not fall below the melting point of the solder material, and the holding time at this temperature must be sufficient for the solder material to melt completely in order to achieve optimal solder joint strength.

[0046] In an exemplary embodiment, the manufacturing process begins with the provision of a complete series of wafers (substrate plate 110 and 35 thin-film circuits 120, totaling 70 solder pads) and a conductor frame 24. The thickness of the conductor frame 24 is approximately 200 to 250 micrometers, and 70 conductors 130 are produced by punching or laser cutting, with the spacing of the conductors 130 being identical to that of the wafers (1.5 to 1.6 millimeters). Nickel wire is used as the material for the conductors 130, while thin nickel-silicon alloy plates with a thickness between 1 and 25 micrometers, preferably 10 micrometers, are used for the solder pads 140.

[0047] The entire array of wafers (substrate plate 110 and 35 thin-film circuits 120) is then aligned on the conductor frame 24, which has 70 conductors 130, using a metal or graphite alignment tool to ensure that the circuit solder pads 122 are aligned with the front-end solder pads 132 of the conductor frame 24. The temperature can then be gradually increased to 850 °C to 950 °C and maintained for approximately 30 minutes, with a reducing protective gas of nitrogen and a small amount of hydrogen ideally being introduced into the soldering oven to prevent oxidation of the conductors 130. This process replaces the conventional manual method of parallel electrode soldering and enables automated production while simultaneously reducing labor.

[0048] After soldering, the individual thin-film element with a positive resistance coefficient of 100 can be obtained by cutting. In an exemplary embodiment, the thin-film element with a positive resistance coefficient of 100 is a wafer 2 millimeters long and 2.4 millimeters wide. The spacing of the circuit solder pads 122 is 1.5 to 1.6 millimeters. The length and width of the circuit solder pads are approximately 0.4 millimeters and 0.4 millimeters, respectively.

[0049] The solder joint force between the circuit solder pads 122 and the front-end solder pads 132 of the thin-film element with a positive resistance coefficient 100 formed by the manufacturing process according to the present exemplary embodiment can be increased from 800 grams per solder pad in conventional parallel electrode soldering to over 5,000 grams without any impairment due to vibrations during use, thus extending the product's service life.

[0050] Fig. Figure 7 shows a three-dimensional schematic view of the element in thin-film form with a positive resistance coefficient according to a further exemplary embodiment of the present application. As can be seen from Fig. As shown in Figure 7 for reference, in the present exemplary embodiment, the substrate plate 110 comprises a first surface 112 and a second surface 114 opposite each other, with the two circuit solder pads 122 located on the first surface 112. Each of the two conductors 130 of the thin-film element with a positive resistance coefficient 100a further comprises a clamping section 134 located at its front end, wherein the front-end solder pad 132 is provided on the first surface 112 of the substrate plate 110, while the clamping section 134 clamps the second surface 114 of the substrate plate 110.

[0051] The clamping action of the front-end solder pad 132 and the clamping section 134 on the first surface 112 and the second surface 114 of the substrate plate 110 generates a holding force, thereby improving the stability of the conductors 130 attached to the substrate plate 110.

[0052] Fig. Figure 8 shows a three-dimensional schematic view of the unpunched conductor frame board material made of Fig. 7. Fig. Figure 9 shows a three-dimensional schematic view of the conductor made of Fig. 8 after punching and bending. It should be noted that in Fig. Figure 9 shows only a ladder frame area with one conductor, while in actual application the ladder frame has multiple conductors.

[0053] As from Fig. 2 as well as Fig. 8 to Fig. As can be seen in Figure 9 as a reference, the manufacture of the conductor 130 according to the present exemplary embodiment, as shown in Fig. Figure 2 shows that step 220 of carrying out the forming process of the conductor frame 24 further comprises: Step 224, punching the conductor frame sheet material 20 to form the conductors 130 and a connecting section 22, each conductor 130 comprising a front-end solder pad 132 located away from the connecting section 22 and a bending section. Subsequently, as shown in Fig. 9 and Fig. 2 shown, step 226, bending the bending section to form the clamping section 134, wherein the clamping section 134 and the front end solder pad 132 are on different planes.

[0054] In an exemplary embodiment, a conductor frame 24 with a thickness of approximately 200 to 250 micrometers can optionally be used in the manufacturing process to form 70 conductors 130 by cutting or laser cutting. The spacing of the conductors 130 is identical to that of the circuit solder pads 122, which is 1.5 to 1.6 millimeters. The conductors 130 are first bent into a bending section 134, the distance between the bending section 134 and the front-end solder pads 132 being determined by the thickness of the substrate plate 110. For example, if the substrate plate 110 is a ceramic substrate plate with a thickness of 500 micrometers, the distance between the bending section 134 and the front-end solder pads 132 is approximately 530 to 560 micrometers to clamp around the substrate plate 110.

[0055] Nickel wire is used as the material for the conductors 130, while thin nickel-silicon alloy plates with a thickness between 1 micrometer and 25 micrometers, preferably 10 micrometers, are used for the solder pads 140. During manufacturing, the entire series of wafers (substrate plate 110 and 35 thin-film circuits 120) is aligned on the conductor frame 24, which has 70 conductors 130, using a metal or graphite alignment tool to ensure that the circuit solder pads 122 are aligned with the front-end solder pads 132 of the conductor frame 24. The temperature can then be gradually increased to 850 °C to 950 °C and held for approximately 30 minutes, ideally with a reducing protective gas of nitrogen and a small amount of hydrogen introduced into the soldering furnace to prevent oxidation of the conductors 130.After soldering, a single element in thin-film form with a positive resistance coefficient of 100Ω can be obtained by cutting.

[0056] The thin-film element with a positive resistance coefficient of 100a, produced according to the manufacturing process of the present exemplary embodiment, achieves a soldering tensile force between the circuit solder pad 122 and the front-end solder pad 132 that is higher than that of a 7,000-gram solder pad. Such a design can be used in environments with vibrations during vehicle operation and engine operation and is characterized by excellent vibration resistance and resistance to high loads, while simultaneously significantly reducing costs.

[0057] In summary, the two conductors of the thin-film element with a positive resistance coefficient according to the present application are cut from a conductor frame such that the thickness of the front-end solder pad is identical to the thickness of the portion of the respective conductor extending outside the substrate plate. Manufacturing the thin-film element with a positive resistance coefficient according to the present application requires only aligning the conductor frames on the substrate plate. After aligning the respective front-end solder pads of the conductor frames with the circuit solder pads of the thin-film circuits, the described thin-film element with a positive resistance coefficient is obtained by soldering and cutting.In contrast to the known state of the art, which requires individual soldering of the solder pads by technicians, the thin-film element with a positive resistance coefficient according to the present application allows for mass production, resulting in an effective saving of working time and effort.

Claims

[1] Thin-film element with positive resistance coefficient (100, 100a), comprising: a substrate plate (110); a thin-film circuit (120) provided on the aforementioned substrate plate (110) and comprising two circuit solder pads (122); and two conductors (130) cut from a conductor frame (24) and comprising two front-end solder pads (132), wherein the two aforementioned front-end solder pads (132) are each soldered to the two aforementioned circuit solder pads (122), wherein the two aforementioned conductors (130) extend outside the aforementioned substrate plate (110) and wherein the thickness of each of the two aforementioned front-end solder pads (132) is identical to the thickness of the part extending outside the aforementioned substrate plate (110). [2] Thin-film element with positive resistance coefficient (100, 100a) according to claim 1, wherein the thickness of each of the two conductors (130) is between 0.05 millimeters and 4 millimeters. [3] Thin-film element with positive resistance coefficient (100, 100a) according to claim 1 or 2, wherein the thickness of each of the two conductors (130) is between 0.1 millimeters and 0.2 millimeters. [4] Thin-film element with positive resistance coefficient (100, 100a) according to any one of claims 1 to 3, wherein the two said front-end solder pads (132) are each soldered to the two said circuit solder pads (122) by means of two solder plates (140), wherein the material of each of the two said solder plates (140) comprises a nickel alloy. [5] Thin-film element with a positive resistance coefficient (100, 100a) according to claim 4, wherein the material of each of the two solder plates (140) comprises a nickel-phosphorus alloy, nickel-silicon alloy, nickel-copper alloy, nickel-zinc alloy, nickel-copper-silicon alloy or nickel-titanium alloy. [6] Thin-film element with positive resistance coefficient (100, 100a) according to claim 4, wherein the thickness of said solder plate (140) is between 0.1 micrometers and 50 micrometers. [7] Thin-film element with a positive resistance coefficient (100, 100a) according to any one of claims 1 to 6, wherein said substrate plate (110) comprises a first surface (112) and a second surface (114) opposite each other, wherein the two said circuit solder pads (122) are located on said first surface (112), wherein each of the two said conductors (130) further comprises a clamping section (134) located at the front end, wherein said front-end solder pad (132) is provided on said first surface (112) of said substrate plate (110), while said clamping section (134) clamps said second surface (114) of said substrate plate (110). [8] Thin-film element with positive resistance coefficient (100, 100a) according to any one of claims 1 to 7, wherein the two conductors (130) comprise two opposing, concave surfaces (136). [9] Thin-film element with a positive resistance coefficient (100, 100a) according to any one of claims 1 to 8, wherein the material of said conductor (130) comprises nickel metal or a nickel alloy.

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