Electronic device and method for manufacturing the same

Abstract

Electronic device and method for manufacturing the same According to one embodiment, an electronic device (100) comprises a sensor element (1) for measuring a physical quantity in the electronic device and a contact element (2) configured to be mechanically biased. The electronic device further comprises a measurement surface (30, 60, 90) on which the physical quantity is measured with the help of the sensor element. The sensor element is disposed on the measurement surface. The contact element is electrically connected to the sensor element. At least one of the connections between the sensor element and the contact element and the connection between the sensor element and the measurement surface is a dry connection. The contact element is mechanically biased to prevent loosening of at least one dry connection.

Description

[Technical Field]

[0001] The present disclosure relates to electronic devices and methods for manufacturing electronic devices. Summary of the Invention [Problem to be solved by the invention]

[0002] It is an object to provide improved electronic devices, for example, electronic devices that are easily manufactured and / or have a compact design. Another object is to provide improved methods for manufacturing such electronic devices. [Means for solving the problem]

[0003] SUMMARY OF THE INVENTION Embodiments of the present disclosure relate to improved electronic devices and improved methods for manufacturing electronic devices.

[0004] First, identify the electronic device: The electronic device described herein may be, for example, a power semiconductor module or an assembly including a power semiconductor module.

[0005] According to one embodiment, an electronic device comprises a sensor element for measuring a physical quantity within the electronic device and a contact element configured to be mechanically biased. The electronic device further comprises a measurement surface on which the physical quantity is measured with the aid of the sensor element. The sensor element is disposed on the measurement surface. The contact element is electrically connected to the sensor element. At least one of the connection between the sensor element and the contact element and the connection between the sensor element and the measurement surface is a dry connection. The contact element is mechanically biased to prevent loosening of the at least one dry connection.

[0006] The described electronic device, on the one hand, improves the quality of determination of physical quantities during operation of the electronic device. On the other hand, it also allows the implementation of sensor elements with relatively little modification of the electronic device, even in electronic devices for which sensor elements were not originally intended. This is due to the use of energizable contact elements. For example, the energized contact elements press two elements of the electronic device between which dry contact is formed against each other, ensuring that the dry contact is maintained. Thus, at least one connection can be achieved without soldering, gluing, sintering, welding, or other joining methods.

[0007] The sensor element is, for example, a transducer (measurand transducer) and is therefore part of a measuring device that responds directly to the measurand. The sensor element may therefore be the first element of a measurement chain. The sensor element is configured to detect a physical quantity, such as temperature, humidity, pressure, acceleration, etc., and in response generates or manipulates an electrical signal that can be read out via a contact element.

[0008] The contact element is at least partially electrically conductive. The contact element comprises a contact area, which is a region remote from the sensor element, in particular opposite the sensor element, and to which the contact element can be electrically connected. The contact element provides a conductive path from the sensor element to the contact area. In this way, it may be possible with the help of the contact element to read out the sensor element, in particular to receive an electrical signal from the sensor element via the contact element and / or to supply an electrical signal to the sensor element via the contact element. The contact element may therefore also be used to supply a voltage and / or a current to the sensor element.

[0009] The contact element may be integrally formed or may consist of several parts. For example, the contact element may be made of or include metal. That the contact element is configured to be mechanically biased means that at least a portion / section of the contact element is resilient and deformable to bring the contact element from its relaxed state to its biased state. In the biased state, the contact element tends to automatically return to its relaxed state. At least one resilient portion of the contact element may, for example, be reversibly deformable. The contact element may comprise one or more deformable, resilient portions / sections, such as a spring. When bringing the contact element from its relaxed state to its biased state, the at least one resilient or deformable portion is, for example, compressed and / or bent and / or deflected. Mechanically biased and mechanically stressed are used synonymously.

[0010] The sensor elements are arranged, for example, between the measuring surface and the contact element or at least a part of the contact element, in particular vertically. In this specification, vertically means a direction perpendicular to the main extension plane of the electronic device or measuring surface. Lateral is a direction parallel to the electronic device or measuring surface.

[0011] The sensor element and the contact element may be adjacent to each other, and the sensor element and the measuring surface may be adjacent to each other.

[0012] The sensor element is mechanically connected to the measuring surface and the contact element. A thermal contact may also be established between the sensor element and the measuring surface. At least one of the (mechanical) connections of the sensor element to the contact element and the measuring surface is a dry connection. A dry connection is a non-material locking connection, i.e. no material locking connection (bond) is formed between the two connected elements / partners. A dry connection is, for example, a pure press-fit and / or form-fit connection. A dry connection can be loosened non-destructively.

[0013] The connection between the sensor element and the contact element is also an electrical connection. Similarly, the connection between the sensor element and the measuring surface may be an electrical connection. Electrical contact between two elements established without a material locking connection, i.e., by a dry connection, is referred to herein as a "dry electrical contact."

[0014] The contact elements are mechanically biased, i.e., in a biased state. In particular, the contact elements are fixed in the electronic device so that transition of the contact elements to their relaxed state is prevented. However, biased contact elements tend to automatically switch to the relaxed state, thereby generating a force in the electronic device. The force can be transmitted to further components of the electronic device, such as a sensor element.

[0015] The mechanically biased contact elements are arranged to prevent loosening of at least one dry connection. This may mean that the force generated by the biased contact elements presses the two elements / partners forming the dry connection together. In this way, the dry connection is maintained.

[0016] For example, the force exerted by a biased contact element in an electronic device is at least 0.01N or at least 0.1N.

[0017] According to a further embodiment, the sensor element is a temperature sensor. For example, the sensor element is a temperature-sensitive resistor, also known as a "thermistor." The sensor element may be a platinum resistor, such as an NTC, PTC, PT100, or PT1000, or a thermocouple. Alternatively, the sensor element may be a humidity sensor, an acceleration sensor, or a pressure sensor.

[0018] Indeed, there is a high level of customer interest in temperature monitoring of, for example, power semiconductor devices (herein also referred to as "power semiconductor chips" or simply "chips") or power semiconductor modules during operation. Temperature monitoring is typically used to protect against overheating of the chip, for example in overcurrent situations, or to monitor the degradation state of the power semiconductor module, for example with regard to aging of bonding connections, which affects the thermal resistance and thus the chip temperature.

[0019] According to at least one embodiment, the contact element comprises or is one of a spring contact element or a pressure contact pin. The spring contact element has, for example, a serpentine-shaped region, a V-shaped region, a U-shaped region, a spring washer region, and / or a spring region that can be compressed to place the contact element in a biased state. Additionally or alternatively, the spring contact element can have a cantilever-shaped portion that can be bent to place the spring contact element in a biased state. The spring contact element can be formed in one piece or from several parts.

[0020] The crimping pin comprises a body, e.g., a barrel or tubular body / sleeve, a tip element, e.g., a plunger, and one or more springs, e.g., spiral springs, that can be compressed to bias the contact element. The tip element is movably mounted relative to the body and can be moved further towards or into the body by compressing the spring. The crimping pin is, for example, an elongated element. The tip element of the crimping pin may be connected to or in contact with the sensor element.

[0021] According to a further embodiment, the connection between the sensor element and the contact element and / or the connection between the sensor element and the measuring surface is realized as a material-locking connection, which may be a soldered, sintered, glued or welded connection or may be realized by any other applicable joining method.

[0022] According to a further embodiment, the sensor element is connected to the measuring surface by a material locking connection. The material locking connection may be of the same nature as that specified in the last paragraph. Also, the electrical connection between the sensor element and the contact element may be provided by the material locking connection, for example exclusively by the material locking connection. Thus, the connection between the sensor element and the contact element is a dry connection, and the electrical contact therebetween may be a dry contact.

[0023] According to a further embodiment, the sensor element can be electrically connected externally via the contact element. For example, the electronic device comprises a terminal area, which is exposed and / or freely accessible and electrically connected to the contact element and thus also to the sensor element. The terminal area may be an area of ​​the contact element, such as the contact area mentioned above. Alternatively, the terminal area may be an area of ​​an auxiliary terminal structure to which the contact element is electrically connected.

[0024] According to a further embodiment, a terminal area for externally electrically connecting the sensor element via a contact element overlaps the sensor element in at least one lateral direction. The terminal area and the sensor element may overlap in two perpendicular lateral directions. In other words, the terminal area at least partially covers the sensor element in a top view of the electronic device, i.e., when viewed along the vertical direction. In this case, the terminal area is, for example, part of the contact element. In this case, the terminal area is offset from the sensor element in the vertical direction. "Offset" in this specification means that there is no overlap between the two respective elements, but rather a gap.

[0025] According to a further embodiment, the terminal area for externally electrically connecting the sensor element via the contact element is offset from the sensor element in at least one lateral direction, for example in two perpendicular lateral directions. In a top view of the electronic device, the terminal area is offset from the sensor element. In the vertical direction, the terminal area may also be offset from the sensor element or overlap the sensor element.

[0026] According to a further embodiment, the sensor element comprises an upper electrode on a top surface of the sensor element. Additionally, the sensor element may comprise a lower electrode on a bottom surface of the sensor element, the bottom surface being opposite the top surface.

[0027] The top and bottom electrodes are, for example, metal regions of the sensor element, which may be configured to electrically connect the sensor element for readout and / or to supply current and / or voltage to the sensor element.

[0028] According to a further embodiment, the contact element is connected to the upper electrode of the sensor element. The contact element and the upper electrode may be in direct contact, i.e., adjacent to each other. The electrical contact may be realized by a connection between the upper electrode and the contact element. For example, a dry connection is formed between the contact element and the upper electrode. Thus, the electrical contact between the sensor element and the contact element may be a dry electrical contact. Alternatively, a material-locked connection may be formed between the sensor element and the contact element.

[0029] According to a further embodiment, the measuring surface is connected to the lower electrode of the sensor element. The measuring surface and the lower electrode may be in direct contact, i.e., adjacent to each other. An electrical contact may be established between the lower electrode and the measuring surface. A material-locked connection may be formed between the measuring surface and the lower electrode. Alternatively, a dry connection may be formed between them.

[0030] According to a further embodiment, the electronic device comprises a power semiconductor device. As an example, the power semiconductor device is a switching device. The power semiconductor device may be an IGBT, a MOSFET, a HEMT, a diode, or a thyristor. In this case, the electronic device is, for example, a power semiconductor module having one or more power semiconductor devices or comprises such a module.

[0031] The power semiconductor module may include a substrate having an upper metallization and, optionally, an lower metallization. At least one power semiconductor device may be attached to a top surface of the substrate where the upper metallization is located, e.g., mounted on the upper metallization. The substrate may be, for example, a direct bonded copper (DBC) substrate, a direct bonded aluminum (DBA) substrate, an active metal bracing (AMB) substrate with an insulating ceramic layer, or an isolated metal substrate (IMS) with an insulating resin layer.

[0032] Furthermore, the power semiconductor module may comprise terminals (main terminals and optionally auxiliary terminals) for external electrical connection. The terminals may be realized, for example, by sheet-like and / or metallic and / or integrally formed terminal structures. Other shapes of the terminals are also possible, such as hollow cylinders with nut-like threads. To enable electrical contact with the outside, the terminal areas of the terminal structures are exposed. The terminal structures may be bonded to or realized by the top metallization. The terminals may directly connect the chips, but may also control electronic devices.

[0033] The power semiconductor module may further include a housing body. The housing body may be formed of an electrically insulating material such as a resin and / or a gel. The power semiconductor device may be embedded in the housing body. The terminal structure may be at least partially embedded in the housing body. A terminal region of the terminal structure may protrude from the housing body, for example, from a side surface of the housing body. The housing body may include a housing frame surrounding a cavity. The cavity may be filled with a gel.

[0034] The power semiconductor module may further include a base plate. The base plate may be, for example, for cooling. The substrate may be attached to the base plate, for example, with the lower metallization facing the base plate. The base plate may be made of a metal such as Cu or Al or an alloy thereof, or a composite material such as aluminum silicon carbide or magnesium silicon carbide. The base plate may include cooling structures, such as pin fins or ribs, on the side facing away from the substrate.

[0035] In this specification, the lateral direction is, for example, a direction parallel to the main extension plane of the substrate, and the vertical direction is a direction perpendicular to the main extension plane of the substrate.

[0036] According to a further embodiment, the sensor element is arranged on the power semiconductor device. According to a further embodiment, the sensor element is arranged in an area adjacent to the power semiconductor device. For example, the sensor element is arranged on an upper metallization of the substrate next to the power semiconductor device and / or between two adjacent power semiconductor devices. The upper metallization can then form the measurement surface.

[0037] Placing the sensor element on the power semiconductor device has several advantages over placing the sensor element on a substrate adjacent to the power semiconductor device or on a separate substrate of the electronic device adjacent to the substrate on which the power semiconductor device is mounted. For example, the quality of the chip temperature determination improves as the distance between the chip and the temperature sensor decreases. In fact, in this case, the true chip temperature can be more accurately derived from the sensor readings using a thermal model. Furthermore, when the sensor element is placed directly on the chip, the temperature change and the corresponding measurement time delay caused by the long distance can be significantly reduced.

[0038] An additional benefit of placing the sensor element on the power semiconductor device is that if two or more heat-generating chips are mounted on the board, the sensor reading will refer primarily to one chip, not the average of the chips. If the sensor element is placed between chips on the board, the measured temperature may not refer to the temperature of the most thermally unfavorable or most degraded chip. In the worst case scenario, severe degradation of the junctions under one chip or the chip itself may go undetected.

[0039] Furthermore, if the sensor element is located on the chip, it is possible to prevent excessively high temperatures of the chip from going undetected due to a deteriorated die bond that does not conduct heat.

[0040] Also, placing the sensor element on the top metallization next to the power semiconductor device consumes space on the substrate surface, reducing the available space for the chip, which can also negatively impact thermal resistance and therefore the rated cost per ampere.

[0041] Additionally, many products are originally developed without a built-in sensor element. As a result, there may not be any available board space for the placement of a sensor element. However, there is a strong trend for customers to request the implementation of a thermal sensor.

[0042] An electronic device may include several of the above-mentioned specific pairs of sensor element and contact element. For example, several power semiconductor devices may each be assigned such a pair, with its sensor element attached to the respective power semiconductor device. It is also possible that one or more sensor elements of one or more such pairs are attached to an upper metallization of one or more substrates next to or between the power semiconductor devices, and one or more sensor elements of one or more such pairs are attached to one or more power semiconductor devices. For example, there may be one such pair per substrate.

[0043] According to a further embodiment, the measurement surface is formed by an upper electrode of the power semiconductor device, which may be, for example, a source / emitter electrode or a drain / collector electrode, and may be made of a metal such as Cu or Al, or a corresponding alloy.

[0044] The sensor reading of the sensor element is, for example, between the contact element and an output terminal (e.g., an AC terminal) of the electronic device. Alternatively, the sensor reading may be between the contact element and an input terminal (e.g., a DC+ or DC- terminal) of the electronic device.

[0045] According to a further embodiment, the contact element is electrically and mechanically connected, in particular fixed, to an auxiliary terminal of the electronic device. The auxiliary terminal is, for example, formed by an auxiliary terminal structure of the electronic device. The auxiliary terminal structure is, for example, a sheet metal element, a nut, or a hollow (metal) cylinder. The auxiliary terminal is different from the main terminal or power terminal of the electronic device. The main terminal may be an AC, DC-, or DC+ terminal. In particular, the auxiliary terminal is configured to carry less current than the main terminal. The auxiliary terminal may be partially embedded in the housing body of the electronic device. The auxiliary terminal may be a terminal for controlling a power semiconductor device, such as for measurement / detection. They may be an auxiliary emitter or collector terminal, a gate terminal, or a terminal for connecting a sensor.

[0046] According to a further embodiment, the contact element is electrically and mechanically connected to the auxiliary terminal by a screw connection. Alternatively, other connections are possible, such as soldering, welding, crimping or adhesive bonding. It is also possible for the contact element to be formed integrally with the auxiliary terminal.

[0047] The auxiliary terminal is, for example, a terminal of an electronic device that can be electrically connected from the outside. That is, the terminal area of ​​the auxiliary terminal is exposed and freely accessible. For example, the terminal area of ​​the auxiliary terminal is exposed and / or protrudes from the side of the housing body. Alternatively, the auxiliary terminal may be exposed and / or protrude vertically from the top surface of the housing body, for example, when the auxiliary terminal is a nut, a vertical pin, or a hollow sleeve.

[0048] In addition to connecting the contact elements to auxiliary terminals, other methods of securing the contact elements within the electronic device are also contemplated.

[0049] According to a further embodiment, the contact element is fixed to an electrical insulating element of the electronic device, such as a housing body and / or a plastic body. This means, in particular, that there is a direct connection between the contact element and the electrical insulating element. Fixation to the electrical insulating element can maintain the contact element in a mechanically biased state. For example, the contact element may be assembled to the housing body and surrounded thereby in a form-fitting manner. Alternatively, a nut (e.g., metal) may be embedded in the housing body, and the contact element may be screwed onto the nut.

[0050] According to a further embodiment, a portion of the contact element is exposed, for example at a top surface of the electronic device. The exposed portion may constitute a terminal area of ​​the contact element for an external electrical connection of the contact element. The sensor element may be electrically supplied and / or read out via the exposed portion.

[0051] According to a further embodiment, a thermally conductive material is arranged between the measurement surface and the sensor element. The thermally conductive material may be a paste filled with fine particles, for example, conductive particles. The thermally conductive material may be electrically conductive or electrically insulating. The paste may be liquid and / or viscous. Alternatively, the thermally conductive material may be a thermally conductive sheet (e.g., an elastic sheet).

[0052] According to a further embodiment, an electronic device comprises at least one, i.e., one or more, power semiconductor modules and a cooler for the power semiconductor modules. The cooler may be a carrier for the power semiconductor modules. The cooler is configured, for example, to guide a coolant therethrough. The cooler may comprise cooling channels for the coolant. The cooler may be made of a metal such as copper or aluminum or a corresponding alloy. The power semiconductor modules may be mounted on the cooler such that the lower metallization and / or the base plate face the cooler.

[0053] According to a further embodiment, the measurement surface is formed by the cooler, for example by its upper surface. The temperature of the cooler may then be measured using the sensor element.

[0054] According to a further embodiment, the measurement surface is formed by the surface of the base plate. The sensor element may then be arranged next to the substrate or between two adjacent substrates attached to the base plate.

[0055] According to a further embodiment, at least one of the surfaces of the two elements where dry contact is formed is roughened, particularly to increase the contact area. The roughened surface may imprint on the adjacent surface, thus increasing the contact area. Furthermore, in this way, a form-fit connection may be established. Furthermore, in this way, undesirable oxide layers may be destroyed and impurities / contaminants on the adjacent surface may be penetrated.

[0056] According to further embodiments, the roughened surface has an average roughness of at least 1 μm, or at least 1.6 μm, or at least 2 μm.

[0057] Next, a method for manufacturing an electronic device is identified. An electronic device according to any of the embodiments described herein can be manufactured with the help of this method. Thus, all features disclosed for the electronic device are also disclosed for the method, and vice versa.

[0058] According to one embodiment, a method for manufacturing an electronic device includes providing a sensor element, providing a contact element configured to be mechanically biased, and providing a member for the electronic device, the member having a measurement surface on which a physical quantity of the electronic device is measured with the help of the sensor element. In a further step, the sensor element is disposed on the measurement surface, and the contact element is electrically connected to the sensor element. At least one of the connection between the contact element and the sensor element and the connection between the sensor element and the measurement surface is a dry connection. In a further step, the contact element is mechanically biased, and at least a portion of the mechanically biased contact element is fixed relative to the member so that the contact element remains in a mechanically biased state to prevent loosening of the at least one dry connection.

[0059] The method steps may be performed in a specified order. That is, after providing the different elements, the sensor element may first be placed on the measurement surface. The contact element may then be electrically connected to the sensor element. The connection between the sensor element and the measurement surface is, for example, a dry connection. The contact element may then be biased and fixed in this biased state. The contact element may also be fixed relative to the member and then biased.

[0060] However, it is alternatively possible to first electrically connect the sensor element and the contact element, for example by a material locking connection, and then attach this composite, also called a sensor unit, to the component by placing the sensor element on the measurement surface, then energizing the contact element, and then fixing the contact element to maintain it in the energized state.

[0061] The component may be, for example, a power semiconductor device, a substrate or an upper metallization of the substrate, a base plate, or a cooler. Thus, the measurement surface may be the upper electrode of the power semiconductor device, or the upper metallization of the substrate, or the surface of the base plate, or the surface of the cooler.

[0062] According to a further embodiment, a material locking connection is formed between the contact element and the sensor element, which material locking connection may also provide an electrical connection between the sensor element and the contact element.

[0063] According to a further embodiment, a material locking connection is formed between the sensor element and the measuring surface, which material locking connection may also provide an electrical connection between the sensor element and the measuring surface.

[0064] According to a further embodiment, a portion of the contact element is fixed relative to the member by means of a threaded connection.

[0065] Hereinafter, an electronic device and a method for manufacturing an electronic device will be described in more detail based on exemplary embodiments with reference to the drawings. The accompanying drawings are included to provide a further understanding. In the drawings, elements of the same structure and / or function may be referred to by the same reference numerals. It should be understood that the embodiments shown in the drawings are illustrative representations and are not necessarily drawn to scale. To the extent that elements or components correspond to each other in terms of their functions in different drawings, the description will not be repeated for each of the following drawings. For clarity, elements may not be labeled with corresponding reference numerals in all drawings. [Brief explanation of the drawings]

[0066] [Figure 1] 1A-1C illustrate different positions in an exemplary embodiment of a method for manufacturing an electronic device and an exemplary embodiment of an electronic device. [Figure 2] 1A-1C illustrate different positions in an exemplary embodiment of a method for manufacturing an electronic device and an exemplary embodiment of an electronic device. [Figure 3] 1A-1C illustrate different positions in an exemplary embodiment of a method for manufacturing an electronic device and an exemplary embodiment of an electronic device. [Figure 4] 1A-1C illustrate different positions in an exemplary embodiment of a method for manufacturing an electronic device and an exemplary embodiment of an electronic device. [Figure 5]5A-5C illustrate different positions in a further exemplary embodiment of a method for manufacturing an electronic device. [Figure 6] 5A-5C illustrate different positions in a further exemplary embodiment of a method for manufacturing an electronic device. [Figure 7] 5A-5C illustrate different positions in a further exemplary embodiment of a method for manufacturing an electronic device. [Figure 8] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 9] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 10] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 11] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 12] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 13] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 14] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 15] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 16] FIG. 1 illustrates a further exemplary embodiment of an electronic device. [Figure 17] FIG. 1 illustrates a further exemplary embodiment of an electronic device. [Figure 18]10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 19] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 20] 10A-10C illustrate different positions in a further exemplary embodiment of the method and a further exemplary embodiment of the electronic device. [Figure 21] FIG. 1 illustrates a further exemplary embodiment of an electronic device. [Figure 22] FIG. 1 illustrates a further exemplary embodiment of an electronic device. DETAILED DESCRIPTION OF THE INVENTION

[0067] 1 shows a location where an exemplary embodiment of a sensor unit 10 for an electronic device 100 is provided. The sensor unit 10 comprises a contact element 2 and a sensor element 1. The contact element 2 is a spring contact element that can be mechanically biased by compressing or bending it. The contact element 2 is formed of a metal such as Cu, Al, or steel, for example.

[0068] The sensor element 1 is, for example, a temperature sensor such as a thermistor. The sensor element may be an NTC, PTC or platinum resistor (e.g. PT100 or PT1000) or a thermocouple. The sensor element 1 comprises an upper electrode 1a and a lower electrode 1b. Both electrodes 1a, 1b may be electrically conductive, in particular made of metal. The electrodes 1a, 1b are arranged to read out the sensor element 1, but may also serve to supply current and / or voltage to the sensor element 1.

[0069] The contact element 2 is fixed to and electrically connected with the sensor element 1, i.e., its upper electrode 1a. The mechanical and electrical connection between the contact element 2 and the sensor element 1 is realized, for example, by a material-locking connection, such as soldering, sintering, welding or adhesive connection. Since the contact element 2 is electrically conductive, the sensor element 1 can be read out with the help of the contact element 2.

[0070] FIG. 2 shows a further location where an assembly of different components 3, 6 for an electronic device is provided. One component is a substrate 6 with an upper metallization 6a. The substrate 6 is, for example, a DBC substrate. A further component is a power semiconductor device 3, also called a power semiconductor chip, which is attached to the upper surface of the substrate 6 and electrically connected thereto via wire bonds. The power semiconductor device 3 has an upper electrode 3a, which constitutes a measuring surface 30, at which a physical quantity is measured with the aid of the sensor element 1 of FIG. 1. By way of example, the power semiconductor device 3 is an IGBT or a power MOSFET, and the upper electrode 3a is the source electrode or emitter electrode, respectively.

[0071] 3 shows the position where the sensor unit 10 of FIG. 1, having the composite of the sensor element 1 and the contact element 2, is placed on the power semiconductor device 3 so that the sensor element 1 is adjacent to the measuring surface 30. No additional connecting material is used between the sensor element 1 and the measuring surface 30 to form a material-locking connection. Therefore, there is a dry connection between the sensor element 1 and the measuring surface 30.

[0072] In the position of Fig. 4, an exemplary embodiment of an electronic device 100 is shown. The electronic device 100 is a power semiconductor module 100. To obtain this power semiconductor module 100 from the arrangement of Fig. 3, the contact elements 2 are compressed or bent, thus assuming their biased state. In this biased state, the contact elements 2 exert a force on the sensor element 1 in a direction towards the measuring surface 30, thereby pressing the sensor element 1 against the measuring surface 30. In this way, the sensor element 1 is firmly held on and connected to the measuring surface 30 due to the increased frictional force (dry connection) and a secure and reliable electrical connection between the measuring surface 30 and the sensor element 1 (dry electrical contact).

[0073] 4 may be manufactured as follows: in the biased state of the contact element 2, a resin 61 is applied onto the substrate 6, encapsulating a part of the contact element 2. After drying the resin 61, the contact element 2 is fixed in its biased state, so that the force that the biased contact element 2 exerts on the sensor element 1 acts against loosening of the dry connection / dry contact. The resulting resin body 61 forms the housing frame 61 of the power semiconductor module 100. The cavity enclosed by the housing frame may be filled, for example with a gel.

[0074] 4 may alternatively be manufactured as follows: a pre-manufactured housing frame 61 may be attached to the substrate 6, and then the contact elements 2 may be clamped to the housing frame 61 to keep them in a biased state. Alternatively, the contact elements may be at least partially embedded in the housing frame as an integral part.

[0075] A portion of the contact element 2 on the top surface of the power semiconductor module 100 is not covered by the resin body 61 and is exposed. This portion constitutes a terminal area of ​​the contact element 2 for external electrical connection of the contact element 2. The sensor element 1 can therefore be read out, for example, via the contact element 2 and a DC or AC terminal of the power semiconductor module 100.

[0076] A power semiconductor module 100 similar to the one described in relation to FIG. 4 can be obtained with another exemplary embodiment of the method described in relation to FIGS.

[0077] In the position of Figure 5, the contact element 2 is provided as described in connection with Figure 1. In contrast to Figure 1, the contact element 2 is not yet connected to the sensor element 1.

[0078] In the position of Figure 6, a sensor element 1, e.g. the same as that described in connection with Figure 1, is positioned on a measuring surface 30 which is realized by a power semiconductor device 3 which is again mounted on a substrate 6. The sensor element 1 is electrically connected and fixed to the power semiconductor device 3 by means of a material-locking connection, e.g. soldering, welding, adhesive or sintering connection.

[0079] In the position of FIG. 7, the contact element 2 of FIG. 5 is placed on the upper electrode 1 a of the sensor element 1 and a dry electrical contact is made between the contact element 2 and the sensor element 1 .

[0080] Here, the contact elements 2 can be biased by compressing or bending and can be partially encapsulated with resin 61 to fix the contact elements 2 in their biased state (see the description in relation to FIG. 4). The resulting power semiconductor module differs from that of FIG. 4 in that a dry connection is formed between the contact elements 2 and the sensor element 1, but not between the sensor element 1 and the measuring surface 30. However, here too, the biased contact elements generate a force in the power semiconductor module 100 that acts against loosening of the dry connection.

[0081] 8 shows a different position of the contact element 2 from the previous exemplary embodiment. In this case, the contact element 2 is formed by a pressure pin. The pressure pin is provided with a spring 22 for urging the tip element or plunger of the pressure pin away from the barrel or hollow sleeve of the pressure pin, respectively.

[0082] The contact element 2 further comprises means 21 for a screw connection, namely an external thread 21 . 9 shows a location where an assembly of different components for an electronic device is provided. This assembly also comprises a substrate 6 and a power semiconductor device 3 mounted thereon. Furthermore, the assembly comprises a resin body 61 in which an auxiliary terminal (structure) 4 is partially embedded. The auxiliary terminal structure 4 protrudes from the right side of the resin body 61, and this protruding part forms a terminal area for the external electrical connection of the auxiliary terminal 4.

[0083] The further exposed part of the auxiliary terminal structure 4 is provided with means 41 for a screw connection, i.e. a through-hole with an internal thread, which is located vertically above the measuring surface 30 of the power semiconductor device 3.

[0084] Below the through-hole, the sensor element 1 is arranged on the measuring surface 30. The sensor element 1 is again fixed to the measuring surface 30 by means of, for example, a material locking connection and is electrically connected.

[0085] A further exemplary embodiment of an electronic device 100 is shown in Figure 10. The electronic device 100 is a power semiconductor module 100 obtained by screwing the contact element 2 of Figure 8 into the through-hole of the auxiliary terminal structure 7 of Figure 9. This brings the tip element of the contact element 2 into mechanical and electrical contact with the sensor element 1, i.e., its upper electrode, forming a dry contact.

[0086] The screwing also compresses the spring 22 of the contact element 2 so that the contact element 2 is biased. As a result, the tip element of the contact element 2 is pressed against the measuring surface 30 by the biased contact element 2, thus forming a reliable dry connection and a reliable dry electrical contact between the contact element 2 and the sensor element 1.

[0087] The screw connection between the auxiliary terminal structure 4 and the contact element 2 fixes the contact element 2 in place and in its biased state. A molding material 7, for example in the form of a gel, is then applied. The molding material 7 and the resin body 61 form the housing body of the power semiconductor module 100. The sensor element 1 can be read out, for example, with the help of the contact element 2 and the auxiliary terminal 4, as well as with the help of further terminals (e.g., main terminals electrically connected to the measuring surface of the chip).

[0088] In the position of FIG. 11, two contact elements 2 are provided, each realized as a pressure contact pin.

[0089] 12 shows a position where an assembly of several components 3, 6, 61, 62 is provided. Here, one component 62 is a circuit board, for example a PCB, attached to the resin body 61 and laterally overlapping the power semiconductor device 3. The component 62 may be a control board and may include a control device. The sensor element 1 is arranged on the power semiconductor device 3 and, for example, fixedly connected thereto.

[0090] 13, the two contact elements 2 of FIG. 11 are attached by screwing them through threaded holes in a circuit board 62 so that they make electrical contact with the sensor element 1. By screwing, the contact elements 2 are mechanically fixed to the circuit board 62 and at the same time mechanically biased, so that the tip elements of the contact elements 2 are pressed against the sensor element 1 to form a reliable dry electrical contact.

[0091] 13, one contact element 2 is in dry electrical contact with the top electrode 1a of the sensor element 1, and the other contact element 2 is in dry electrical contact with the bottom electrode 1b. The sensor element 1 can therefore be read out with the help of both contact elements 2.

[0092] As shown in FIG. 13, the lower electrode 1b projects laterally beyond the upper electrode 1a to allow contact of both the upper electrode 1a and the lower electrode 1b with the contact element 2 from the top surface.

[0093] Alternatively, the sensor element 1 can be provided with two electrodes 1a and 1b on its top surface, so that the sensor element 1 can also be contacted with two contact elements 2 from the top surface.

[0094] 13 shows a further exemplary embodiment of an electronic device 100 in the form of a power semiconductor module 100. In this case, both contact elements 2 of the sensor unit 10 project vertically from the circuit board, with terminal areas of both contact elements 2 being exposed on the top side of the power semiconductor module 100. These terminal areas of the two contact elements 2 can be electrically connected for readout of the sensor element 1.

[0095] 14 shows the position where the assembly of the substrate 6, the power semiconductor device 3 and the resin body 61 is provided. A hole is formed in the resin body 61 above the upper metallization 6a. In this case, the upper metallization 6a forms a measurement surface 60 on which a physical quantity, for example temperature, is measured. The sensor element 1 is arranged on this upper surface in the region of the hole in the resin body 61.

[0096] In the position of Figure 15, the contact element 2 of Figure 8 is attached by screwing it into a hole in the resin body 61 so that the contact element 2 comes into contact with the sensor element 1. To enable screwing, the hole in the resin body 61 may be provided with an internal thread. Alternatively, an internally threaded nut may be embedded in the resin body (not shown).

[0097] 16 shows an exemplary embodiment of an electronic device 100 that is a power semiconductor module 100. In this case, a thermally conductive material 5, e.g. in the form of a paste filled with electrically and / or thermally conductive particles, such as metal particles, or a flexible material sheet, is arranged between the sensor element 1 and the measuring surface 30. Dry electrical contact can be made between the material 5 and the sensor element 1 and between the material 5 and the measuring surface 30. The sensor element 1 can be fixed to the contact element 2 by a material locking connection.

[0098] 16, the thermally conductive material 5 is also electrically conductive to establish electrical contact between the upper electrode 3a and the sensor element 1. When such a thermally conductive material 5 is used in the exemplary embodiment of FIG. 13, the material 5 can be, for example, electrically insulating.

[0099] In the exemplary embodiment of the electronic device 100 of FIG. 17, the tip element of the contact element 2 includes a roughening having a plurality of protrusions and recesses. The roughening has an average roughness of, for example, 1.6 μm or more. When the contact element 2 is pressed against the upper electrode of the sensor element 1 by the energized contact element 2, the protrusions imprint on the upper electrode, thereby improving the dry connection, for example, by penetrating and / or locally destroying the oxide layer that develops. For this purpose, the upper electrode may be relatively soft compared to the material of the roughened surface.

[0100] 18 shows a position where a further exemplary embodiment of a contact element 2 for an electronic device is provided. In this case, the contact element 2 comprises an insulation displacement pin as described above and further a terminal structure 24 mechanically and electrically connected to the insulation displacement pin. This connection can be established in various ways, for example by screwing, soldering, gluing, sintering, welding, etc. The terminal structure 24 is a sheet-like element and may be made of a metal, for example Cu or a Cu alloy.

[0101] 19, an assembly of different components for an electronic device 100 is again provided, comprising a substrate 6, a power semiconductor device 3 and a resin body 61. The sensor element 1 is placed and fixed on a measurement surface 30 formed by the upper electrode 3a of the power semiconductor device 3.

[0102] Figure 20 shows an exemplary embodiment of an electronic device 100 in the form of a power semiconductor module 100, which is manufactured, inter alia, by attaching the contact element 2 of Figure 18 to the assembly of Figure 19. The auxiliary terminal structures 24 are, for example, glued to the resin body 61 so that the insulation displacement pins are maintained in their biased state. In Figure 20, the power semiconductor device 3 and parts of the contact elements 2 are embedded in the casting 7, for example in the form of a gel. The terminal structures 24 constitute auxiliary terminals of the power semiconductor module 100.

[0103] 21 shows an exemplary embodiment of an electronic device 100 in a top view on a measurement surface 30. As can be seen, the sensor element 1 is positioned on the measurement surface 30 laterally between two adjacent bond wires, which are electrically and mechanically connected to the top electrode 3 a of the power semiconductor device 3.

[0104] FIG. 22 shows an exemplary embodiment of an electronic device 100 in the form of an assembly of two power semiconductor modules 8 mounted on a cooler 9. The cooler 9 is configured to cool the power semiconductor modules 8. For example, the cooler 9 comprises channels for guiding a coolant through the cooler 9. The cooler 9 is formed of a metal, such as Cu or Al. The exposed surface of the cooler 9 serves as a measuring surface 90. A nut 91 having an internal thread is attached to the measuring surface 90. The sensor element 1 is arranged on the measuring surface 90 in the region of the hole in the nut 91. The contact element 2 of FIG. 8 is screwed into the nut 91, so that a dry electrical contact is formed between the sensor element 1 and the contact element 2. The contact element 2 is fixed to the nut 91 in its biased state by a threaded connection.

[0105] Instead of the cooler 9 forming the measurement surface, the base plate of the power semiconductor module may also form the measurement surface.

[0106] The embodiments shown in Figures 1-22 above represent exemplary embodiments. As such, they do not constitute an exhaustive list of all embodiments of the improved electronic devices and improved methods. Actual electronic devices and methods may differ from the illustrated embodiments, for example, in terms of arrangement, devices, and elements. [Explanation of symbols]

[0107] Reference sign 1. Sensor element 1a Upper electrode 1b Lower electrode 2 Contact Elements 3 Power semiconductor devices 3a Upper electrode 4 Auxiliary terminal (structure) 5. Thermally conductive materials 6 PCB 6a Top Metallization 7 Casting / Gel 8 Power Semiconductor Modules 9 Cooler 10. Sensor unit for electronic devices 21 Threaded connection means 22 Spring 24 Auxiliary terminal structure 30 Measurement surface 41 Threaded connection means 60 Measurement Surface 61 Resin / Resin body / Housing frame 62 Circuit Board 90 Measuring surface 91 Nut 100 Electronic Devices

Claims

1. An electronic device (100), comprising: a sensor element (1) for measuring a physical quantity in said electronic device (100); a contact element (2) configured to be mechanically biased; a measuring surface (30, 60, 90) on which the physical quantity is measured with the help of the sensor element (1); Equipped with The sensor element (1) is arranged on the measuring surface (30), The contact element (2) is electrically connected to the sensor element (1), at least one of the connection between the sensor element (1) and the contact element (2) and the connection between the sensor element (1) and the measuring surface (30, 60, 90) is a dry connection; the contact element (2) is mechanically biased to prevent loosening of the at least one dry connection; the sensor element (1) is connected to the measuring surface (30, 40, 50) by a material-locking connection, An electronic device (100) in which a dry electrical contact is formed between said contact element (2) and said sensor element (1).

2. The sensor element (1) is a temperature sensor. The electronic device (100) of claim 1.

3. The contact element (2) comprises a spring contact or a pressure contact pin, 3. An electronic device (100) according to claim 1 or 2.

4. a terminal area for externally electrically connecting the sensor element (1) via the contact element (2) overlaps the sensor element (1) in at least one lateral direction; An electronic device (100) according to any one of the preceding claims.

5. a terminal area for externally electrically connecting the sensor element (1) via the contact element (2) is offset from the sensor element (1) in at least one lateral direction; An electronic device (100) according to any of the preceding claims.

6. The sensor element (1) comprises an upper electrode (1a) on an upper surface of the sensor element (1) and a lower electrode (1b) on a lower surface of the sensor element (1) opposite to the upper surface, the contact element (2) is connected to the upper electrode (1 a) of the sensor element (1), The measuring surface (30, 60, 90) is connected to the lower electrode (1b) of the sensor element (1). An electronic device (100) according to any of the preceding claims.

7. Further comprising a power semiconductor device (3), The sensor element (1) is arranged on the power semiconductor device (3). An electronic device (100) according to any one of the preceding claims.

8. The measurement surface (30) is formed by the upper electrode (3a) of the power semiconductor device (3). The electronic device (100) of claim 7.

9. The contact element (2) is electrically and mechanically connected to an auxiliary terminal (4) of the electronic device (100) by a screw connection; The auxiliary terminal (4) can be electrically connected from the outside. An electronic device (100) according to any one of the preceding claims.

10. The contact element (2) is fixed to an electrically insulating element of the electronic device (100), An electronic device (100) according to any one of the preceding claims.

11. A portion of the contact element (2) is exposed and constitutes a terminal area of ​​the contact element (2) for external electrical connection of the contact element (2). An electronic device (100) according to any one of the preceding claims.

12. A method for manufacturing an electronic device (100), comprising: Providing a sensor element (1); Providing a contact element (2) configured to be mechanically biased; providing an element (3, 6, 9) for an electronic device (100), the electronic device (100) having a measuring surface (30, 60, 90) on which a physical quantity of the electronic device (100) is measured with the help of the sensor element (1); placing the sensor element (1) on the measuring surface (30, 60, 90); electrically connecting the contact element (2) and the sensor element (1), at least one of the connection between the contact element (2) and the sensor element (1) and the connection between the sensor element (1) and the measuring surface (30, 60, 90) is a dry connection; Mechanically biasing said contact element (2); fixing at least a portion of the mechanically biased contact element (2) relative to the member (3, 6, 9) so that the contact element (2) remains in a mechanically biased state to prevent loosening of at least one of the dry connections; Including, the sensor element (1) is connected to the measuring surface (30, 40, 50) by a material-locking connection, A method in which a dry electrical contact is formed between the contact element (2) and the sensor element (1).

13. a part of the contact element (2) is fixed to the member (3, 6, 9) by a screw connection; The method of claim 12.

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