Sensor element and method of manufacturing a sensor element

Abstract

Sensor element and method of manufacturing a sensor element The present invention concerns a sensor element (1) for measuring a temperature comprising a carrier (2), a temperature dependent resistor (10) arranged on a top side (2a) of the carrier (2), and a shunt resistor (20) arranged on the top side (2a) of the carrier (2), wherein the temperature dependent resistor (10) comprises a first electrode (12), a second electrode (13) and a functional layer (11) comprising a material having a temperature dependent electrical resistance, wherein the first and the second electrodes (12, 13) are thin film electrodes and the functional layer (11) is a thin film, wherein the shunt resistor (20) is electrically connected to at least one of the electrodes (12, 13) of the temperature dependent resistor (10), and wherein the shunt resistor (20) is formed by a thin film. Another aspect concerns a method of manufacturing the sensor element.

Description

[0001] P2024, 1206 WO N December 3, 2025

[0002] 1

[0003] Description

[0004] SENSOR ELEMENT AND METHOD OF MANUFACTURING A SENSOR ELEMENT

[0005] The present invention relates to a sensor element, preferably a temperature sensor, and to a method of manufacturing a sensor element.

[0006] To integrate passive components, such as sensors, capacitors, heaters, etc., the dimensions for modern packaging solutions must be adapted to the micrometer, or even nanometer, scale. To achieve such miniaturization, thin film technologies must be used. For processing, thin film NTC structures are deposited on a substrate, e.g. Si-wafers.

[0007] However, an output voltage provided by a NTC thermistor often has to be linearized to further process the output signal provided by the NTC thermistor.

[0008] It is an object of the present invention to describe a sensor element with improved properties. For example, a sensor element may be provided which has a small form factor. A small form factor is often necessary for modern packaging solutions. Another object concerns a method for manufacturing a sensor element with improved properties.

[0009] This object is solved by a sensor element and by a method of manufacturing a sensor element according to the independent claims .

[0010] According to one aspect, a sensor element is described. The sensor element is adapted for measuring a temperature. The sensor element is a temperature sensor element. P2024 , 1206 WO N December 3 , 2025

[0011] The sensor element comprises a carrier . The carrier has a top side and a bottom side . The carrier may comprise silicon, silicon carbide or glass ( silicates or borosilicates ) . Alternatively, the carrier may comprise AIN, AI2O3 or SiaN4 , for example .

[0012] The top side of the carrier may be electrically insulating . This implies , for example , that a carrier comprising silicon needs one or more insulating layers comprising e . g . SiCt , AIN or SiaN4 . The one or more insulating layers may have thickness of less than 1 . 5 pm . The carrier may comprise a rectangle or quadratic shape .

[0013] The sensor element comprises a temperature dependent resistor . The temperature dependent resistor may be an NTC (negative temperature coef ficient ) thermistor . The temperature dependent resistor is arranged on the top side of the carrier . Preferably, the temperature dependent resistor is arranged directly on the top side of the carrier . In other words , at least one electrode of the temperature dependent resistor and / or a functional layer of the temperature dependent resistor directly abuts the top side of the carrier .

[0014] The temperature dependent resistor comprises at least two electrodes and a functional layer . The functional layer comprises a material having a temperature dependent electrical resistance . The functional layer may be a thin film with NTC properties . The functional layer may have a thickness in the range of 1 nm and 1 pm, preferably between 100 nm and 500 nm and ideally between 250 nm and 400 nm . P2024, 1206 WO N December 3, 2025

[0015] A material of the functional layer may comprise; : a) Oxides: For example Perowskites (based on mixed crystals of the CaMnOs material system where Ca is fully or partially substituted with either Or, Y, Al or La) or Spinell (based on mixed crystals of the NiMn2O4 material system where Ni and / or Mn are partially substituted with Fe, Co, Al) or a Vanadium oxide ; b) Carbides, for example (Si,Ti)C, 2H, 4H or 6H, cubic SiC; c) Nitrides for example (Al,Ti)N, CrN.

[0016] Each of the two electrodes is a thin film electrode. Each of the two electrodes may comprise single or multiple layers of thin film metals, with materials comprising Cu, Au, Ni, Cr, Ag, Ti, W, Pd, Al or Pt, for example. Each of the two electrodes may consist of a single layer or of multiple layers of thin film metals, in particular of one or more of the above cited metals.

[0017] The temperature dependent resistor may comprise a specific nominal electrical resistance. The functional layer and the electrodes are designed and / or arranged and / or connected such that a specific nominal electrical resistance of the temperature dependent resistor can be achieved. In other words, the functional layer and the electrodes comprise a specific material, specific contact area and / or a specific position relative to one another to control the resistance of the temperature dependent resistor.

[0018] The sensor element comprises a shunt resistor which is arranged on the top side of the carrier. Preferably, the shunt resistor is arranged directly on the top side of the carrier. The shunt resistor may comprise a metal structure which may comprise single or multiple layers of thin film P2024 , 1206 WO N December 3 , 2025

[0019] 4 metals , with materials comprising Cu, Au, Ni , Or, Ag, Ti , W, Pd, Al or Pt , for example . The metal structure may consist of a single layer or of multiple layers of thin film metals , in particular of one or more of the above cited metals .

[0020] The shunt resistor is electrically connected to at least one of the electrodes of the temperature dependent resistor . The shunt resistor is formed by a thin film .

[0021] The shunt resistor may be a precision resistor . The resistance of the shunt resistor may be low compared to the resistance of the temperature dependent resistor at a nominal temperature or the resistance of the shunt resistor may be high compared to the resistance of the temperature dependent resistor at the nominal temperature . The shunt resistor is chosen depending on the intended use case of the sensor element .

[0022] The shunt resistor may act as a voltage divider . By acting as a voltage divider the shunt resistor may be configured to lineari ze the output voltage of the sensor element at a speci fic temperature range .

[0023] The resistance of the shunt resistor is not temperature dependent . Other characteristics of the shunt resistor may also not be temperature dependent .

[0024] The temperature dependent resistor and the shunt resistor are both manufactured by thin film technology . The temperature dependent resistor and the shunt resistor are arranged on a common carrier . Accordingly, a sensor element is provided which is configured to provide a lineari zed output signal .

[0025] For further processing of an output signal provided by the P2024 , 1206 WO N December 3 , 2025 sensor element , additional discrete elements for lineari zing the output signal can be omitted .

[0026] When the sensor element is used in an electrical circuit , no extra shunt resistor has to be mounted adj acent to the sensor element as the shunt resistor is already integrated in the sensor element . The output signal provided by the sensor element is already lineari zed . Due to the use of thin film technology, the sensor element has a very small si ze . For example , the sensor element may have width and a length which are both in the range of 200 pm to 2000 pm . The sensor element may have a thickness in the range of 20 pm to 200 pm, preferably of 50 pm to 100 pm .

[0027] According to an embodiment , the shunt resistor is electrically connected in series to the temperature dependent resistor . Accordingly, a second electrode of the temperature dependent resistor may be connected to a first electrode of the shunt resistor . The second electrode of the temperature dependent resistor and the first electrode of the shunt resistor may coincide . In other words , the second electrode of the temperature dependent resistor and the first electrode of the shunt resistor may be unitarily formed in one piece .

[0028] In particular, a single , continuous thin film metal structure may form both of the second electrode of the temperature dependent resistor and the first electrode of the shunt resistor . Said metalli zation may, for example , be a rectangle without any interruptions or holes .

[0029] A first electrode of the temperature dependent resistor may form a first terminal of the sensor element . A second electrode of the shunt resistor may form a second terminal of the sensor element . The second electrode of the temperature P2024 , 1206 WO N December 3 , 2025 dependent resistor and the first electrode of the shunt resistor may together form a third terminal of the sensor element . The sensor element may be configured such that a resistance change of the temperature dependent resistor can be measured between the first terminal and the third terminal . An output voltage and an output signal of the sensor element is lineari zed by the addition of the shunt resistor . The sensor element may be configured such that an electrical connection to an external circuit may be possible via each of the first terminal , the second terminal and the third terminal .

[0030] Alternatively, the first electrode of the temperature dependent resistor may be connected to the first terminal of the sensor element . The second electrode of the shunt resistor may be connected to the second terminal of the sensor element . One of the second electrode of the temperature dependent resistor and the first electrode of the shunt resistor may be connected to the third terminal . For example , contact pads forming the terminals may be arranged above the respective electrode .

[0031] According to an embodiment , the shunt resistor may comprise two electrodes being connected to each other by a structured metalli zation . Each of the electrodes may have a comparatively large area which may enable an easy integration in the sensor element and may allow a stable , low resistance connection to the temperature dependent resistor or to a terminal . The structured metalli zation may form a structure which comprises locally thin parts to generate a high resistivity . The structured metalli zation may substantially define the resistance of the shunt resistor . P2024 , 1206 WO N December 3 , 2025

[0032] According to an embodiment , the structured metalli zation may form a meandering path connecting the electrodes . By using a meandering path instead of a straight path, the length of the path connecting the electrodes can be increased such that the resistance of the shunt resistor is increased compared to a straight connection .

[0033] According to an embodiment , the structured metalli zation may form a spiraling path connecting the electrodes . A spiraling path may provide the advantage of a homogenous distribution of heat generated in the path . Moreover, a spiraling path allows a small form factor and a high resistance to be provided .

[0034] According to an embodiment , the structured metalli zation may form multiple paths , each connecting the electrodes . The multiple paths may be parallel to each other . By providing more than one path connecting the electrodes of the shunt resistor, it becomes possible to fine-tune the resistance of the shunt resistor by cutting one or more paths before finishing the sensor element .

[0035] The structured metalli zation may comprise one or more trimmable sections which are configured to be removed for fine-tuning the resistance of the final shunt resistor . This may allow to change the resistance of the shunt resistor to better match a rated resistance .

[0036] According to an embodiment , the shunt resistor comprises a first metalli zation of a first metal and a second metalli zation of a second metal which is di f ferent from the first metal . Each of these metalli zations may be formed by thin films . P2024 , 1206 WO N December 3 , 2025

[0037] - 8 -

[0038] The shunt resistor may have a resistance which is in the range of 0 . 1 to two times the resistance of the temperature dependent resistor . The resistances may be considered at the rated temperature of the temperature dependent resistors , for example at room temperature .

[0039] The shunt resistor may comprise one or more layers of at least one of the following materials : Pt , Ni , Or, Al , Au, Cu, Ag, W, Pd and Ti . These materials provide a low temperature coef ficient of resistance . Preferably, but not exclusively, metals or alloys are used for the shunt resistor . To match the relatively high resistances of the temperature dependent resistor, a metal with a relatively high resistivity is preferred for the shunt resistor, for example NiCr . The electrodes and the structured metalli zation of the shunt resistor may consist of the same material as the electrodes of the temperature dependent resistor .

[0040] According to an embodiment , the sensor element comprises a second shunt resistor which is arranged on the carrier . The second shunt resistor may be formed by a thin film . The first shunt resistor is connected in series to the temperature dependent resistor and the second shunt resistor is electrically connected parallel to the temperature dependent resistor .

[0041] Connecting a second shunt resistor in parallel to the temperature dependent resistor may further improve the lineari zation of an output signal provided by the sensor element . P2024 , 1206 WO N December 3 , 2025

[0042] According to an embodiment , the second shunt resistor has a resistance which is in the range of 0 . 01 to 50 times the resistance of the temperature dependent resistor . The resistances may be considered at the rated temperature of the temperature dependent resistors , for example at room temperature .

[0043] According to an embodiment , the sensor element has a thickness in the range of 20 pm to 200 pm . The use of the thin film technology enables to construct a sensor element of such a small thickness .

[0044] Another aspect concerns a method of manufacturing a sensor element . The method is particularly suited for manufacturing the above-described sensor element . Accordingly, each functional and structural feature disclosed with respect to the sensor element can also apply to the method and vice versa .

[0045] The method of manufacturing a sensor element for measuring a temperature comprises the following steps : step S I : providing a carrier material , step S2 : forming a temperature dependent resistor and a shunt resistor on a top side of the carrier by thin film technology, wherein the temperature dependent resistor comprises a first electrode , a second electrode and a functional layer comprising a material having a temperature dependent electrical resistance , wherein each of the first electrode , the second electrode and the functional layer is a thin film structure , wherein the shunt resistor is electrically connected to at least one of the electrodes ( of the temperature dependent resistor, and wherein the shunt resistor is formed as a thin film structure . P2024, 1206 WO N December 3, 2025

[0046] Step S2 may comprise multiple sub-steps. The electrodes of the temperature dependent resistor, the electrodes of the shunt resistor and the structured metallization of the shunt resistor may be formed in a single process step. Alternatively, at least some of said elements may be formed in a separate process step.

[0047] Each of steps SI and S2 may be carried our on a wafer level, i.e. before singulating the wafer into multiple sensor elements, e.g. by cutting.

[0048] In a step S3 which is carried out after step S2, the terminals of the sensor element are formed. In a subsequent step S4, the carrier material is singulated into single sensor elements 1, i.e. by dicing and grinding. Step S4 may also be performed on wafer level.

[0049] Further advantages, features and further developments are set out by the following exemplary embodiments which are explained in conjunction with the figures.

[0050] The drawings described below are not intended to be to scale. Rather, individual dimensions may be enlarged, reduced or even distorted for better representation.

[0051] The same or similar elements or elements acting in the same way are provided with the same reference numerals in the figures, wherein:

[0052] Figure 1 shows a sensor element 1 according to a first embodiment . P2024 , 1206 WO N December 3 , 2025

[0053] Figure 2 shows a sensor element 1 according to a second embodiment .

[0054] Figure 3 shows a sensor element 1 according to a third embodiment .

[0055] Figure 4 shows a sensor element 1 according to a fourth embodiment .

[0056] Figure 5 shows a sensor element 1 according to a fi fth embodiment .

[0057] Figure 6 shows a sensor element 1 according to a sixth embodiment .

[0058] Figure 7 shows a sensor element 1 according to a seventh embodiment .

[0059] Figure 8 shows a flow chart of a method of manufacturing a sensor element .

[0060] Figure 1 shows a sensor element 1 according to a first embodiment . The sensor element 1 is a temperature sensor . The sensor element 1 comprises a temperature dependent resistor 10 and a shunt resistor 20 . The temperature dependent resistor 10 is a thermistor, in particular an NTC thermistor .

[0061] The sensor element 1 has a top side and a bottom side . A thickness of the sensor element 1 is < 200 pm, preferably < 100 pm and ideally < 60 pm . The thickness of the sensor element may be in the range of 100 pm to 20 pm, preferably in the range of 80 pm to 40 pm or in the range of 80 pm to 50 pm . In this regard, the thickness denotes an extension of the P2024 , 1206 WO N December 3 , 2025

[0062] - 12 - sensor element 1 in a stacking direction, i . e . the extension perpendicular to a main direction of extension of the sensor element 1 .

[0063] The sensor element 1 comprises a carrier 2 having a top side 2a and a bottom side . The carrier 2 preferably comprises silicon, silicon carbide or glass ( silicates or borosilicates ) . Alternatively, AIN, AI2O3 or SiaN4 are also possible materials of the carrier 2 . Both of the temperature dependent resistor 10 and the shunt resistor 20 are arranged on the carrier 2 .

[0064] The top side 2a of the carrier 2 is electrically insulating . This implies , for example , that a carrier 2 comprising silicon needs an insulating layer comprising e . g . SiCt . A thickness of the insulating layer arranged on the top side 2a of the carrier 2 may be between 50 nm and 1 pm, preferably between 250 nm and 600 nm . Ideally, the thickness is 500 nm . The sensor element 1 is preferably a rectangle and may be quadratic . An edge length of the sensor element 1 is < 2000 pm, preferably < 800 pm and ideally < 500 pm .

[0065] The carrier 2 is formed by singulating a wafer comprising a carrier material . On the singulated carrier 2 , one temperature dependent resistor 10 and one shunt resistor 20 are arranged .

[0066] The temperature dependent resistor 10 comprises a functional layer 11 . The functional layer 11 comprises a material with special electrical characteristics ( temperature dependent electrical resistance ) . The functional layer 11 is a thin film with NTC properties . P2024, 1206 WO N December 3, 2025

[0067] Possible materials for the functional layer 11 are: a) Oxides: For example Perowskites (based on mixed crystals of the CaMnOs material system where Ca is fully or partially substituted with either Y, Or, Al or La) or Spinell (based on mixed crystals of the NiMn2O4 material system where Ni and / or Mn are partially substituted with Fe, Co, Al) or a Vanadium oxide ; b) Carbides, for example (Si,Ti)C, 2H, 4H or 6H, cubic SiC; c) Nitrides for example (Al,Ti)N, CrN.

[0068] A layer thickness of the functional layer 11 is between 1 nm and 1 pm, preferably between 100 nm and 500 nm and ideally between 250 nm and 400 nm.

[0069] The temperature dependent resistor 10 comprises a first electrode 12 and a second electrode 13. In the embodiment shown in Figure 1, both electrodes 12, 13 are arranged directly on the carrier 2. Both electrodes are spaced apart from each other. The two electrodes 12, 13 comprise interdigitated fingers. In an alternative embodiment, one of the two electrodes 12 is a bottom electrode, which is arranged directly on the carrier 2, and the other of the two electrodes 13 is a top electrode which is arranged above the functional layer 11, wherein the functional layer 11 is arranged above the bottom electrode.

[0070] Of course, the temperature dependent resistor 10 can comprise more than two electrodes. For example, the temperature dependent resistor 10 may comprise multiple top electrodes and / or multiple bottom electrodes. The temperature dependent resistor 10 may also comprise more than two electrodes arranged directly on the carrier 2. P2024 , 1206 WO N December 3 , 2025

[0071] 14

[0072] Each electrode 12 , 13 may comprise single or multiple layers of thin film metals , with materials being Cu, Au, Ni , Cr, Ag, Ti , W, Pd, Al or Pt . Each electrode 12 , 13 may consist of single or multiple layers of these thin film metals .

[0073] In the first embodiment , both electrodes 12 , 13 of the temperature dependent resistor 10 are arranged directly on the top side 2a of the carrier 2 . In an alternative embodiment , in which a conductive material is used for the carrier 2 , both electrodes 12 , 13 are arranged directly on the insulating layer 6 disposed on the top side 2a of the carrier 2 .

[0074] Both electrodes 12 , 13 are arranged directly under the functional layer 11 . In other words , both electrodes 12 , 13 are at least partly in direct electrical and mechanical contact with the functional layer 11 . The first electrode 12 is electrically connected to the second electrode 13 via the functional layer 11 . In an alternative embodiment , the functional layer 11 is arranged directly on the carrier 2 or on an insulating layer covering the carrier 2 . In the alternative embodiment , the electrodes 12 , 13 are arranged on the functional layer 11 on a side of the functional layer 11 facing away from the carrier 2 .

[0075] The shunt resistor 20 comprises a first electrode 21 , a second electrode 22 and a structured metalli zation 23 which electrically connects the two electrodes 21 , 22 . The structured metalli zation 23 forms a path connecting the two electrodes 21 , 22 . The path comprises multiple stripes 24 . The stripes 24 have a width which is very small compared to the length of the stripes 24 , wherein the length is defined as the longest extension of each stripe 24 and the width is P2024 , 1206 WO N December 3 , 2025

[0076] 15 defined as the extension in a direction perpendicular to the length . For example , the length of each stripe may be larger than four times the width of the stripe .

[0077] The small width of the stripes 24 results in the structured metalli zation 23 having a large resistance . Overall , the shunt resistor 20 has a precisely defined resistance . The materials used for the shunt resistor 20 may have a relatively low resistivity . However, by forming a path with stripes having a well-defined length and a well-defined width, a desired resistance can be achieved .

[0078] The first electrode 21 of the shunt resistor 20 is electrically connected to the second electrode 13 of the temperature dependent resistor 10 . The first electrode 21 of the shunt resistor 20 and the second electrode 13 of the temperature dependent resistor 10 may also coincide . In other words , the two electrodes 21 , 13 may be formed in one piece , for example by a single continuous metal area .

[0079] The shunt resistor 20 and the temperature dependent resistor 10 are connected in series . The shunt resistor 20 is configured to lineari ze an output signal of the temperature dependent resistor 10 . Accordingly, it is not necessary to combine the temperature dependent resistor 10 with a discrete element for lineari zing the output signal .

[0080] The two electrodes 21 , 22 and the structured metalli zation 23 of the shunt resistor 20 are arranged directly on the top surface 2a of the carrier 2 . Both electrodes 21 , 22 and the structured metalli zation 23 may be deposited in the same process step which is preferred when the same materials are used for the electrodes 21 , 22 and the structured P2024, 1206 WO N December 3, 2025

[0081] 16 metallization 23. Alternatively, both electrodes 21, 22 and the structured metallization 23 may be deposited in different process steps which is preferred when different materials are used for the electrodes 21, 22 and the structured metallization 23.

[0082] In an alternative embodiment in which the top surface 2a is covered by an insulating layer, the two electrodes 21, 22 and the structured metallization 23 are arranged directly on the insulating layer. In another alternative embodiment, the two electrodes 21, 22 may be arranged in two different layers, for example, the first electrode 21 of the shunt resistor 20 may be arranged in the same layer as the top electrode of the temperature dependent resistor 10 and the second electrode 22 of the shunt resistor 20 may be arranged in the same layer as the bottom electrode of the temperature dependent resistor 10.

[0083] Each of the electrodes 21, 22 and the structured metallization 23 of the shunt resistor 20 may comprise single or multiple layers of thin film metals, with materials being Cu, Au, Ni, Cr, Ag, Ti, W, Pd, Al or Pt. The electrodes 21, 22 and the structured metallization 23 of the shunt resistor 20 may consist of single or multiple layers of these thin film metals. The electrodes 21, 22 of the shunt resistor 20 and the structured metallization 23 of the shunt resistor 20 may be made from the same material or materials as the electrodes of the temperature dependent resistor.

[0084] Accordingly, both the shunt resistor 20 and the temperature dependent resistor 10 are manufactured in thin film technology. The electrodes 21, 22 and the structured metallization 23 of the shunt resistor 20 can be integrally P2024 , 1206 WO N December 3 , 2025 formed in one piece . It is also possible that the electrodes 21 , 22 and the structured metalli zation 23 of the shunt resistor 20 and the second electrode 13 of the temperature dependent resistor 10 are integrally formed in one piece . Accordingly, the electrodes 21 , 22 and the structured metalli zation 23 - and possibly also the second electrode of the temperature dependent resistor 10 - are formed in one process step . In an alternative embodiment , the formation of the electrodes 21 , 22 , the structured metalli zation 23 and the second electrode of the temperature dependent resistor 10 is split into multiple steps . For example , the electrodes 21 , 22 may be formed first and in a subsequent step, the structured metalli zation 23 is formed . Afterwards , the terminal can be formed . In another alternative embodiment , at least one electrode may be formed in another layer compared to the other electrodes .

[0085] The temperature dependent resistor 10 and the shunt resistor 20 are placed on the same carrier 2 . They form a single sensor element 1 wherein a first terminal 3 of the sensor element 1 is connected to the first electrode 12 of the temperature dependent resistor 10 and a second terminal 4 of the sensor element 1 is connected to the second electrode 22 of the shunt resistor 20 . A third terminal 5 of the sensor element 1 is connected to the second electrode 13 of the temperature dependent resistor 10 and / or to the first electrode 21 of the shunt resistor 20 . The first terminal 3 is formed by a contact pad which is arranged above the first electrode 12 of the temperature dependent resistor 10 , i . e . , on a side of the electrode 12 facing away from the carrier 2 .

[0086] The second terminal 4 is formed by a contact pad which is arranged above the second electrode 22 of the shunt resistor 20 , i . e . , on a side of the electrode 22 facing away from the P2024 , 1206 WO N December 3 , 2025

[0087] 18 carrier 2 . The third terminal 5 is formed by a contact pad which is arranged above the second electrode 13 of the temperature dependent resistor 10 , i . e . , on a side of the electrode 13 facing away from the carrier 2 .

[0088] The sensor element 1 is configured to be electrically connected via the first terminal 3 , the second terminal 4 and the third terminal 5 . The resistance of the temperature dependent resistor 10 is measured between the first terminal 3 and the third terminal 5 . An output voltage provided by the sensor element 1 is lineari zed by the integration of the shunt resistor 20 .

[0089] In the first embodiment , the structured metalli zation 20 forms a meandering path . By structuring the structured metalli zation into a meandering path, it is possible to precisely define the resistance of the shunt resistor 20 , especially for higher resistance values .

[0090] Figure 2 shows a second embodiment of the sensor element 1 .

[0091] The second embodiment di f fers from the first embodiment in the shape of the structured metalli zation 23 . In the second embodiment , the structured metalli zation 23 forms a spiraling path which connects the first electrode 21 of the shunt resistor 20 to the second electrode 22 of the shunt resistor 20 .

[0092] The spiraling path has a small form factor for a high resistance . The spiraling path provides a homogenous distribution of Joule heat generated in the shunt resistor 20 during the operation of the sensor element 1 . P2024 , 1206 WO N December 3 , 2025

[0093] 19

[0094] Figure 3 shows a third embodiment of the sensor element 1 . In the third embodiment , the structured metalli zation 23 forms multiple paths which connect the first electrode 21 of the shunt resistor 20 to the second electrode 22 of the shunt resistor 20 . In particular, the structured metalli zation 23 forms multiple stripes 24 which are parallel to each other, each stripe 24 connecting the two electrodes 21 , 22 to each other .

[0095] The design shown in Figure 3 is particularly suitable for high resistivity materials . For the design of the third embodiment , trimming is possible . For example , one or more paths formed by the structured metalli zation 23 may be cut to trim the resistance of the shunt resistor 20 in the finished sensor element 1 . The paths may be cut e . g . by laser trimming . Trimming can be used for fine-tuning of the resistance of the finished sensor element 1 .

[0096] In a variation of the third embodiment , some of the stripes 24 may be formed by a first metal and some of the stripes 24 may be formed by a second metal which is di f ferent from the first metal . The use of two di f ferent metals increases the trimming possibilities , thereby allowing an easy trimming for fine-tuning of the resistance .

[0097] Figure 4 shows a fourth embodiment of the sensor element 1 . In the fourth embodiment , the structured metalli zation 23 of the shunt resistor 20 forms a meandering path connecting the two electrodes 21 , 22 of the shunt resistor 20 . Additionally, the structured metalli zation 23 forms a trimmable section 25 which forms a shortcut in the meandering path . The trimmable section 25 shortens the length of the meandering path . The trimmable section 25 is configured to be removed for fine- P2024 , 1206 WO N December 3 , 2025

[0098] 20 tuning the resistance of the final shunt resistor 20 . The trimmable section 25 is in particular configured to be cut of f by means of a laser, by sawing or by grinding . Removing the trimmable section 25 increases the resistance of the structured metalli zation 23 . This allows for a very good fine-tuning towards a rated resistance of the shunt resistor 20 .

[0099] In a modi fication of the fourth embodiment , the structured metalli zation 23 may comprise multiple trimmable sections 25 , each being configured to be removed independently of the other trimmable sections 25 and each providing a shortcut in the path formed by the structured metalli zation 23 .

[0100] Figure 5 shows a fi fth embodiment of the sensor element 1 . The fi fth embodiment is substantially based on the second embodiment in which the structured metalli zation 23 forms a spiraling path . In the fi fth embodiment , a trimmable section 25 is formed by a second metalli zation 26 shortcutting parts of the path formed by the structured metalli zation 23 . Some or all of the shortcuts in the path generated by the trimmable section 25 may be cut for fine-tuning the resistance of the shunt resistor 20 . Each cut allows the resistance of the shunt resistor 20 to be increased, thereby enabling a fine-tuning of the resistance .

[0101] The second metalli zation 26 forming the trimmable sections 25 may either consist of the same material as the structured metalli zation or comprise a di f ferent material from the structured metalli zation 23 .

[0102] Figure 6 shows a sixth embodiment of the sensor element 1 . P2024 , 1206 WO N December 3 , 2025

[0103] 21

[0104] In the sixth embodiment , the structured metalli zation 23 comprises two di f ferent metals . A first group of stripes 24a is formed by the first metal and a second group of stripes 24b is formed by the second metal . The two electrodes 21 , 22 are connected to each other by a meandering path formed by alternating stripes 24a, 24b of the first metal and of the second metal . The stripes 24a, 24b of the two di f ferent metals are connected in series .

[0105] In each of the embodiments shown in Figures 1 to 6 , the same temperature dependent resistor 10 is used which comprises the interdigital electrodes 12 , 13 and the functional layer 11 connecting the two electrodes 12 , 13 . However, each of these embodiments may also be combined with a di f ferent temperature dependent resistor 10 , for example , with a temperature dependent resistor 10 , wherein a bottom electrode is arranged directly on the carrier 2 or on an insulating layer covering the carrier 2 and wherein a functional layer 11 and a top electrode are stacked on the bottom electrode . Moreover, in each of the embodiments , the electrodes 12 , 13 of the temperature dependent resistor 10 may also comprise trimmable sections which allow the resistance of the temperature dependent resistor to be fine-tuned .

[0106] In each of the embodiments shown in Figure 1 to 6 , the shunt resistor 20 is arranged lateral of the temperature dependent resistor 10 wherein the first electrode 12 of the temperature dependent resistor 10 is arranged in line with the second electrode 22 of the shunt resistor 20 and wherein the second electrode 13 of the temperature dependent resistor 10 is arranged in line with the first electrode 21 of the shunt resistor 20 . P2024 , 1206 WO N December 3 , 2025

[0107] 22

[0108] However, the temperature dependent resistor 10 and the shunt resistor 20 may also be arranged in a di f ferent arrangement . For example , the shunt resistor 20 may be arranged on the left side or on the right side of the temperature dependent resistor 10 when seen in a top view . Accordingly, a straight line can be drawn from the first electrode 12 of the temperature dependent resistor 10 through each of the functional layer 11 , the second electrode 13 of the temperature dependent resistor 10 , the first electrode 21 of the shunt resistor 20 , the structured metalli zation 23 and the second electrode 22 of the shunt resistor 20 in this order .

[0109] Figure 7 shows a seventh embodiment of the sensor element . In the seventh embodiment , a second shunt resistor 120 is connected in parallel to the temperature dependent resistor 10 . A first electrode 121 of the second shunt resistor 120 is connected to the first electrode 12 of the temperature dependent resistor 10 and a second electrode 122 of the second shunt resistor 120 is connected to the second electrode 13 of the temperature dependent resistor 10 .

[0110] The second shunt resistor 120 is formed by thin film technology . The second shunt resistor 120 comprises a single or multiple layers of thin film metals . The second shunt resistor 120 is also arranged on the top side 2a of the carrier 2 . The design options disclosed above with respect to the first shunt resistor 20 can also be used for the second shunt resistor 120 . For example , the structured metalli zation of the second shunt resistor may form a meandering path, a spiraling path, multiple paths parallel to each other or may have a di f ferent shape . The structured metalli zation of the P2024 , 1206 WO N December 3 , 2025

[0111] 23 second shunt resistor may comprise trimmable sections and / or may be composed of more than one metal .

[0112] In the example shown in Figure 7 , the shunt resistor 20 is arranged on the right side of the temperature dependent resistor 10 in a top view of the sensor element 1 . The second shunt resistor 120 is arranged below the temperature dependent resistor 10 in a top view of the sensor element 1 . However, other arrangements of each of the shunt resistor 20 and the second shunt resistor 120 with respect to the temperature dependent resistor 10 and with respect to each other are also possible .

[0113] In the following, a method for manufacturing the sensor element 1 is disclosed . Figure 8 shows a flow chart of the method .

[0114] In a first step S I , a carrier material is provided . The carrier material is provided on a wafer level .

[0115] In a subsequent step S2 , the temperature dependent resistor 10 , the shunt resistor 20 and possibly the second shunt resistor 120 is formed on the carrier material in thin film technology . Multiple temperature dependent resistors 10 , shunt resistors 20 and possibly second shunt resistors 120 are formed on the carrier material on wafer level .

[0116] Step S2 comprises multiple sub-steps . For example , in one sub-step of S2 , each of the electrodes 12 , 13 of the temperature dependent resistor 10 , the electrodes 21 , 22 of the shunt resistor 20 and the structured metalli zation 23 of the shunt resistor 20 - and possibly also the electrodes and the structured metalli zation of the second shunt resistor 120 P2024, 1206 WO N December 3, 2025

[0117] 24

[0118] - may be formed in a single process step. Alternatively, some or all of these elements may be formed in separate process steps. In another sub-step of S2 the functional layer is formed by thin film technology. This sub-step may be carried out before or after forming the metal structures. In another sub-step, insulating layers of the temperature dependent resistor 10, the shunt resistor 20 and possibly the second shunt resistor 120 are formed by thin film technology. In a step S3 which is carried out after step S2, the terminals 3, 4, 5 of the sensor element 1 are formed. In a subsequent step S4, the carrier material is singulated into single sensor elements 1, i.e. by dicing and grinding.

[0119] P2024 , 1206 WO N December 3 , 2025

[0120] 25

[0121] Reference numbers

[0122] 1 sensor element

[0123] 2 carrier

[0124] 2a top side of the carrier

[0125] 3 first terminal

[0126] 4 second terminal

[0127] 5 third terminal

[0128] 10 temperature dependent resistor

[0129] 11 functional layer

[0130] 12 first electrode

[0131] 13 second electrode

[0132] 20 shunt resistor

[0133] 21 first electrode

[0134] 22 second electrode

[0135] 23 structured metalli zation

[0136] 24 stripe

[0137] 24a stripe

[0138] 24b stripe

[0139] 25 trimmable section

[0140] 26 second metalli zation

[0141] 120 second shunt resistor

[0142] 121 first electrode of the second shunt resistor

[0143] 122 second electrode of the second shunt resistor

Claims

1. P2024, 1206 WO N December 3, 2025Claims (We claim)1. Sensor element (1) for measuring a temperature comprising- a carrier ( 2 ) ,- a temperature dependent resistor (10) arranged on a top side (2a) of the carrier (2) , and- a shunt resistor (20) arranged on the top side (2a) of the carrier ( 2 ) , wherein the temperature dependent resistor (10) comprises a first electrode (12) , a second electrode (13) and a functional layer (11) comprising a material having a temperature dependent electrical resistance, wherein each of the first electrode (12) , the second electrode (12, 13) and the functional layer (11) is a thin film structure, wherein the shunt resistor (20) is electrically connected to at least one of the electrodes (12, 13) of the temperature dependent resistor (10) , and wherein the shunt resistor (20) is formed as a thin film structure .

2. Sensor element (1) according to claim 1, wherein the shunt resistor (20) is electrically connected in series to the temperature dependent resistor (10) .

3. Sensor element (1) according to one of the preceding claims , wherein the shunt resistor (20) comprises a first electrode (21) and a second electrode (22) being connected to each other by a structured metallization (23) .P2024, 1206 WO N December 3, 2025- 27 -4. Sensor element (1) according to the preceding claim, wherein the sensor element (1) comprises a first terminal (3) , a second terminal (4) and a third terminal (5) for connecting the sensor element (1) to an external circuit, wherein the first terminal (3) of the sensor element (1) is connected to the first electrode (12) of the temperature dependent resistor (10) , wherein the second terminal (4) of the sensor element (1) is connected to the second electrode (22) of the shunt resistor (20) , and wherein the third terminal (5) of the sensor element (1) is connected to the second electrode (13) of the temperature dependent resistor (10) and / or to the first electrode (21) of the shunt resistor (20) .

5. Sensor element (1) according to one of claims 3 or 4, wherein the structured metallization (23) forms a meandering path connecting the electrodes (21, 22) of the shunt resistor (20) .

6. Sensor element (1) according to one of claims 3 or 4, wherein the structured metallization (23) forms a spiraling path connecting the electrodes (21, 22) of the shunt resistor (20) .

7. Sensor element (1) according to one of claims 3 or 4, wherein the structured metallization (23) forms multiple paths connecting the electrodes (21, 22) of the shunt resistor (20) .

8. Sensor element (1) according to one of claims 3 to 7,P2024, 1206 WO N December 3, 2025 wherein the structured metallization (23) comprises a trimmable section (25) which is configured to be removed for fine-tuning the resistance of the final shunt resistor (20) .

9. Sensor element (1) according to one of the preceding claims , wherein the shunt resistor (20) comprises a first metallization of a first metal and a second metallization (26) of a second metal which is different from the first metal.

10. Sensor element (1) according to one of the preceding claims , wherein the shunt resistor (20) has a resistance which is in the range of 0.1 to 2 times the resistance of the temperature dependent resistor (10) .

11. Sensor element (1) according to one of the preceding claims , wherein the shunt resistor (20) comprises at least one of Pt, Ni, Cr, Al, Au, Cu, Ag, W, Pd and Ti.

12. Sensor element (1) according to one of the preceding claims , comprising a second shunt resistor (120) which is arranged on the carrier (2) , wherein the second shunt resistor (120) is formed by a thin film, wherein the second shunt resistor (120) is electrically connected to at least one of the electrodes (12, 13) of the temperature dependent resistor (10) .

13. Sensor element (1) according to the preceding claim,P2024, 1206 WO N December 3, 2025 wherein the second shunt resistor (120) is electrically connected parallel to the temperature dependent resistor (10) .

14. Sensor element (1) according to claim 12 or claim 13, wherein the second shunt resistor (120) has a resistance which is in the range of 0.01 to 50 times the resistance of the temperature dependent resistor (10) .

15. Sensor element (1) according to one of the preceding claims , wherein the sensor element (1) has a thickness in the range of 20 pm to 200 pm.

16. Sensor element (1) according to one of the preceding claims , wherein the shunt resistor (20) is arranged lateral of the temperature dependent resistor (10) , wherein the first electrode (12) of the temperature dependent resistor (10) is arranged in line with a second electrode (22) of the shunt resistor (20) and wherein the second electrode (13) of the temperature dependent resistor (10) is arranged in line with a first electrode (21) of the shunt resistor (20) .

17. Method of manufacturing a sensor element (1) for measuring a temperature comprising the steps of- providing a carrier material,- forming a temperature dependent resistor (10) and a shunt resistor (20) on a top side (2a) of the carrier material by thin film technology, wherein the temperature dependent resistor (10) comprises a first electrode (12) , a second electrode (13) and a functionalP2024, 1206 WO N December 3, 2025 layer (11) comprising a material having a temperature dependent electrical resistance, wherein each of the first electrode (12) , the second electrode (12, 13) and the functional layer (11) is a thin film structure, wherein the shunt resistor (20) is electrically connected to at least one of the electrodes (12, 13) of the temperature dependent resistor (10) , and wherein the shunt resistor (20) is formed as a thin film structure .

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