Arrangement for measuring the temperature of at least one component

Abstract

Arrangement (1) for measuring the temperature of at least one component (2), comprising the at least one component (2) and at least one temperature sensor (10), wherein a thermal coupling from the at least one component (2) to the at least one temperature sensor (10) is effected by means of a bonding wire (11), wherein the bonding wire (11) is arranged on one side on or next to the component (2) and on the other side on or next to the temperature sensor (10), wherein the component (2) is designed as a power semiconductor (3) and the power semiconductor (2) is arranged on a metallically coated ceramic (4), wherein the temperature sensor (10) is arranged on the same metallically coated ceramic (4), characterized in that an insulation trench (12) is formed by a completely metal-free structure around the temperature sensor (10).

Description

[0001] The invention relates to at least one arrangement for measuring the temperature of at least one component.

[0002] Knowing the temperature of a component is often very important, for example, to initiate timely countermeasures to prevent thermal damage. Another reason is that properties such as operating parameters often change with temperature.

[0003] DE 196 30 902 B4 discloses a device for monitoring the temperature of a power semiconductor device, in particular a power semiconductor module, comprising an electrically insulating carrier plate having metallization surfaces on which at least one power semiconductor component is arranged. A temperature-dependent electrical resistance element is used as the temperature sensor. The resistance component is a silicon chip resistor with metallizations on its upper and lower main surfaces, which is mounted on a metallization surface on the carrier plate.

[0004] To improve accuracy, the temperature sensor should be positioned as close to the component as possible. For example, it is common practice to position a temperature sensor directly on a power semiconductor, but this is complex to manufacture. It is also often difficult to position a temperature sensor directly next to a power semiconductor due to the limited space required due to the high packing density. These problems frequently arise with other components as well.

[0005] A generic arrangement for temperature measurement is known from DE 10 2013 213 448 A1.

[0006] Similar arrangements are known from DE 10 2018 220 949 A1 and EP 3 926 679 A1.

[0007] The invention is based on the technical problem of creating an improved arrangement for measuring the temperature of a component.

[0008] The solution to the technical problem results from an arrangement having the features of claim 1. Further advantageous embodiments of the invention emerge from the subclaims.

[0009] The arrangement for measuring the temperature of at least one component comprises the at least one component and at least one temperature sensor, wherein a thermal coupling from the at least one component to the at least one temperature sensor is effected by means of a bonding wire, wherein the bonding wire is arranged on one side on or next to the component and on the other side on or next to the temperature sensor. The bonding wire has no electrical function but serves only as a thermal coupling element. The advantage of this arrangement is that the component and temperature sensor can be arranged spatially apart from one another. Due to its low mass, the bonding wire reacts very quickly to temperature changes, so that the temperature behavior or dynamics of the component can be observed. The bonding wire is preferably arranged on the component and on the temperature sensor so that interference is minimized.The bonding wire can be made of gold, copper, silver, or aluminum, for example. However, other highly thermally conductive materials are also conceivable, as long as they can be bonded well. The temperature sensor can be connected to an evaluation circuit that generates control signals based on the temperature values ​​(e.g., controlling a cooling device and / or a display device and / or the component).

[0010] Furthermore, the at least one component is designed as at least one power semiconductor arranged on a metallically coated ceramic. For example, the ceramic is made of aluminum oxide or aluminum nitride, with a copper coating applied using direct bonded copper (DBC). Alternatively, the ceramic can also be designed as silicon nitride, with the copper being applied using active metal brazing (AMB).

[0011] Furthermore, the temperature sensor is mounted on the same metallically coated ceramic, with an isolation trench formed by a completely metal-free structure surrounding the temperature sensor. This provides better thermal isolation of the temperature sensor from other sources, as heat from the other sources would otherwise be conducted to the temperature sensor via the copper.

[0012] In one embodiment, the temperature sensor has at least two electrical connections, wherein the temperature sensor has a further connection which is connected in a thermally conductive and electrically insulated manner to a housing and / or a sensor element of the temperature sensor.

[0013] In a further embodiment, the temperature sensor is designed as an SMD temperature sensor.

[0014] In a further embodiment, the further connection is designed as a solder ring, solder pin, QFN pin (Quad Flat No Leads pin) or pad connection, the latter in particular facilitating direct bonding.

[0015] In a further embodiment, the arrangement comprises at least four power semiconductors forming a half-bridge circuit, wherein at least two power semiconductors connected in parallel form the high-side switches and at least two power semiconductors connected in parallel form the low-side switches.

[0016] In one embodiment, two temperature sensors are then provided, one bonding wire being arranged between the high-side switches and the other bonding wire being arranged between the low-side switches, so that an average temperature of the power semiconductors is determined.

[0017] Alternatively, each high-side and low-side switch can be equipped with a bond wire connected to a temperature sensor. This allows the respective temperature of the individual power semiconductors to be measured very precisely and dynamically, allowing individual power semiconductors to be switched off if necessary. Furthermore, the temperature behavior can be used to determine the SOH (state of health) of the power semiconductors.

[0018] Alternatively, a temperature sensor can be assigned to only one high-side switch and one low-side switch.

[0019] The invention is explained in more detail below using preferred embodiments. The figures show: Fig. 1 a schematic plan view of an arrangement for temperature measurement and Fig. 2 a further schematic representation of an arrangement for temperature measurement.

[0020] In the Fig. 1 shows an arrangement 1 for measuring the temperature of components 2, wherein the components 2 are designed as power semiconductors 3. The power semiconductors 3 are, for example, MOSFETs or IGBTs. The four power semiconductors 3 are arranged on a ceramic 4 with a metallization 5. The four power semiconductors 3 together form a half-bridge. The two upper power semiconductors 3 and the two lower power semiconductors are connected in parallel so that the current is split. The two upper power semiconductors 3 are the high-side switches and the two lower power semiconductors 3 are the low-side switches. The upper power semiconductors 3 are connected to a positive potential of a voltage source via a terminal 6. The lower power semiconductors 3 are connected to a negative potential of the voltage source via a terminal 7. A terminal 8 is a center tap of the half-bridge.The upper power semiconductors 3 are electrically connected to the center tap and the lower power semiconductors 3 are electrically connected to the connection 7 via bond wires 9. The arrangement 1 also has two temperature sensors 10, each of which is connected to a power semiconductor 3 by means of a bond wire 11. The bond wire 11 is connected directly to the power semiconductor 3. An isolation trench 12 is arranged around the temperature sensors 10, in which metallization is completely absent, so that the temperature sensors 10 are better thermally decoupled from the other elements on the ceramic 4. The advantage of this arrangement 1 is that, on the one hand, the temperature sensor 10 is largely decoupled from the other thermal sources and, at the same time, the temperature directly above the bond wire 11 on the component 2 orPower semiconductor 3 is detected, whereby, due to the low mass of the bonding wire 11 and its good thermal conductivity, dynamic temperature changes are also detected very quickly. As an alternative to the representation in . Fig. 1, a temperature sensor 10 can also be assigned to each power semiconductor 3. It is also conceivable to arrange the bonding wire 11 between the two power semiconductors 3 of a half-bridge, so that an average temperature of the power semiconductors 3 is detected. The area within the insulation trench 12 can also be referred to as a temperature island.

[0021] In the Fig.Figure 2 shows an alternative representation of an arrangement 1 for temperature measurement, with the focus here being on the temperature sensor 10. The temperature sensor 10 has two electrical connections 13, which are designed as solder caps 14. The temperature sensor 10 is designed as an SMD temperature sensor, with the solder caps 14 being attached to connection pads 20. The temperature sensor 10 also has a further connection 15, which is designed as a solder ring 16 and is attached to a connection pad 17. The further connection 15 is connected in a thermally conductive and electrically insulated manner to a housing 19 and / or a sensor element of the temperature sensor 10. It is also shown how the bonding wire 11 is connected to the connection pad 17 and a pad 18 on the component 2. Also shown is an evaluation and control unit 21, which is electrically connected to the temperature sensor 10.The electrical connection 22 can be designed as a bonding wire or as a conductor track, depending on the embodiment. If, for example, the evaluation and control unit 21 is arranged together with the temperature sensor 10 on the temperature island, the electrical connection can be designed as a conductor track. If, on the other hand, the evaluation and control unit 21 is arranged spatially separately on the ceramic 4 or even outside the ceramic 4, the electrical connection 22 is preferably designed as a bonding wire. However, it is also conceivable for the connection between the temperature sensor 10 and the evaluation and control unit 21 to be wireless (e.g., optical or radio). Finally, it should be noted that the temperature sensor 10 can also be arranged outside the ceramic 4. List of reference symbols 1 arrangement 2 component 3 power semiconductors 4 Ceramics 5 Metallization 6 Connection 7 Connection 8 Connection 9 Bond wire 10 Temperature sensor 11 Bonding wire 12 Isolation trench 13 Connection 14 Soldering cap 15 Connection 16 solder ring 17 Connection pad 18 Pads 19 housings 20 connection pads 21 Evaluation and control unit 22 electrical connection

Claims

[1] Arrangement (1) for measuring the temperature of at least one component (2), comprising the at least one component (2) and at least one temperature sensor (10), wherein a thermal coupling from the at least one component (2) to the at least one temperature sensor (10) is effected by means of a bonding wire (11), wherein the bonding wire (11) is arranged on one side on or next to the component (2) and on the other side on or next to the temperature sensor (10), wherein the component (2) is designed as a power semiconductor (3) and the power semiconductor (2) is arranged on a metallically coated ceramic (4), wherein the temperature sensor (10) is arranged on the same metallically coated ceramic (4), characterized by that around the temperature sensor (10) there is an insulation trench (12) which is formed by a completely metal-free structure. [2] Arrangement according to claim 1, characterized bythat the temperature sensor (10) has at least two electrical connections (13), wherein the temperature sensor (10) has a further connection (15) which is connected in a thermally conductive and electrically insulated manner to a housing (19) and / or a sensor element of the temperature sensor (10). [3] Arrangement according to claim 2, characterized by that the further connection (15) is designed as a solder ring (16), solder pin, QFN pin or pad connection. [4] Arrangement according to one of the preceding claims, characterized by that the temperature sensor (10) is designed as an SMD temperature sensor. [5] Arrangement according to one of the preceding claims, characterized by that the arrangement (1) has at least four power semiconductors (3) which form a half-bridge circuit, wherein at least two power semiconductors (3) connected in parallel form the high-side switches and at least two power semiconductors (3) connected in parallel form the low-side switches. [6] Arrangement according to claim 5, characterized by that at least two temperature sensors (10) are provided, wherein a bonding wire (11) is arranged between the high-side switches and the first temperature sensor (10) and another bonding wire (11) is arranged between the low-side switches and the second temperature sensor. [7] Arrangement according to claim 5, characterized by that a bonding wire (11) is arranged on each high-side and low-side switch, which is connected to a temperature sensor (10).

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