Conductive structure for a fluid cooling system for a semiconductor chip and vehicle

Abstract

A conductive structure for fluid cooling of a semiconductor chip is proposed. The conductive structure comprises a housing for conducting a fluid and a semiconductor chip arranged in the housing. Furthermore, the conductive structure comprises a conductive grid arranged in the housing and an electrical contact for electrically contacting the conductive grid. The conductive structure further comprises two capacitor plates.

Description

[0001] The present invention relates to a conductive structure for fluid cooling for a semiconductor chip and a vehicle.

[0002] The power dissipation density of modern semiconductors is constantly increasing in many applications, and with it the requirements for heat dissipation. A low thermal resistance to a heat sink is desirable, as this positively influences the maximum current, the bulk resistance, and the component's service life. Direct flow of a suitable fluid around a semiconductor offers significantly better heat dissipation. Therefore, there is a need to provide a conductive structure for fluid cooling of a semiconductor chip.

[0003] The object of the invention is achieved by a conductive structure for fluid cooling for a semiconductor chip and a vehicle according to the independent claims.

[0004] According to a first aspect, a conductive structure for fluid cooling for a semiconductor chip is proposed. The conductive structure comprises a housing for conducting a fluid and a semiconductor chip arranged in the housing. Furthermore, the conductive structure comprises a conductive grid arranged in the housing and an electrical contact for electrically contacting the conductive grid. The conductive structure further comprises two capacitor plates. The two capacitor plates comprise an electrical contact for applying an electrical voltage. By arranging the conductive grid within the housing, conductive particles that may be located within the fluid can be electrostatically charged. This means that conductive particles can be electrostatically charged by the conductive grid, thus enabling separation by means of the two capacitor plates.The interaction between the conductive grid and the two capacitor plates allows for the filtering or separation of conductive particles. This can reduce fluid contamination. In particular, it can reduce the likelihood of damage to the semiconductor chip caused by particles within the fluid.

[0005] In one embodiment, the conductive grid can comprise a plurality of conductive grid elements. Individual grid elements of the plurality of conductive grid elements can be arranged one behind the other in a flow direction. By using a plurality of conductive grid elements, the number of electrostatically charged particles after passing through the conductive grid can be increased. This means that the probability that an uncharged, conductive particle is electrostatically charged after passing through the conductive grid can be increased by the plurality of conductive grid elements.

[0006] In one embodiment, the conductive grid may include openings with a width of at least 50 µm and a maximum of 3 mm. This allows the conductive grid to electrostatically charge non-charged conductive particles without becoming clogged by them.

[0007] In one embodiment, the conductive structure may further comprise a third capacitor plate. A longitudinal extension of the third capacitor plate may be parallel to a longitudinal extension of the housing. Furthermore, the third capacitor plate may be arranged centrally within the housing.

[0008] In one embodiment, the conductive structure may comprise a sieve. The openings of the sieve may be larger than the openings of the conductive grid. The sieve can filter out particles that could clog the conductive grid. This can improve the operation of the conductive structure.

[0009] According to a second aspect, a fluid cooling system is proposed. The fluid cooling system comprises a conductive structure as described above and a device comprising a data processing circuit and an interface. The device can be configured to apply a first voltage to the conductive grid and a second voltage to the two capacitor plates. Accordingly, the device can enable operation of the fluid cooling system.

[0010] In one embodiment, the device can be configured to obtain voltage data indicative of a voltage drop across the electrical grid and to determine a particle concentration within the conductive structure based on the voltage data. This allows for a simplified determination of fluid contamination.

[0011] In one embodiment, the fluid cooling may be connected to a radiator, an electric motor, a battery, and / or a transmission for cooling.

[0012] According to a third aspect of the invention, a vehicle is proposed. The vehicle comprises a guide structure as described above or a fluid cooling system as described above.

[0013] The present invention will be described below by way of example only, with reference to the accompanying figures. They show: Fig. 1a and Fig. 1b shows schematic cross-sectional views of various conductive structures for fluid cooling for a semiconductor chip; Fig. 2 shows a view of a fluid cooling system; and Fig. 3 shows an embodiment of a vehicle.

[0014] Fig. 1a and Fig. 1b shows schematic cross-sectional views of various conductive structures 100, 100b for fluid cooling for a semiconductor chip. Fig. 1a shows a conductive structure 100 for fluid cooling of a semiconductor chip. The conductive structure 100 comprises a housing 110 for conducting a fluid and a semiconductor chip 120 arranged in the housing 110. The semiconductor chip 120 can be arranged, for example, on a printed circuit board 122. The printed circuit board 122 is only an example. For example, the semiconductor chip 120 can also be arranged on an interposer, a leadframe, etc.

[0015] The semiconductor chip 120 may heat up during operation. This means that the semiconductor chip 120 may represent a heat source. Accordingly, it may be necessary to enable cooling of the semiconductor chip 120. A fluid can be guided past the semiconductor chip 120 through the conductive structure 100. For example, the fluid can be Fig. 1a from left to right (indicated by the arrows 160, which represent the volume flow 160) past the semiconductor chip 120. This allows the fluid to actively cool the semiconductor chip 120.

[0016] Particles dissolved in the fluid, for example, particles torn off from the circuit board 122, can lead to damage to the semiconductor chip 120. Since the fluid can be conducted in an at least partially closed circuit, it may therefore be necessary to filter out dissolved particles from the fluid.

[0017] Accordingly, the conductive structure 100 comprises a conductive grid 130 arranged in the housing 110 and an electrical contact (not shown) for electrically contacting the conductive grid 130. The conductive grid 130 can electrostatically charge non-charged conductive particles 150 dissolved in the fluid. The electrostatic charging of the non-charged conductive particles 150 allows the electrostatically charged particles 152 to be separated from the fluid in a simplified manner. For example, an electric field 142 can exert a force on the electrostatically charged particles 152, which can lead to a desired deflection of the electrostatically charged particles 152, for example, to a particle sink. This can reduce the number of conductive particles dissolved in the fluid.

[0018] Accordingly, the conductive structure 100 further comprises two capacitor plates 140. The two capacitor plates 140 comprise an electrical contact for applying an electrical voltage. The two capacitor plates 140 can form an electric field 142, which can lead to a force transfer to the electrostatically charged particles 152. Accordingly, the electrostatically charged particles can be deflected from a positive pole (the upper capacitor plate 140) toward a negative pole (the lower capacitor plate 140). As a result, the electrostatically charged particles 152 can be collected in a region of the conductive structure 100. This can, in particular, facilitate the separation of the electrostatically charged particles 152. As a result, a concentration of conductive particles dissolved in the fluid can be reduced.

[0019] The conductive structure 100 can therefore enable direct fluid cooling, particularly in power electronics. Due to the high voltages (>1000V), the insulating properties of the coolant can be particularly important. Particles, such as small metal particles, that can become detached from the system (e.g., through piping, from a metal-core circuit board, or from direct bonded copper, etc.) can lead to short circuits. This can be particularly problematic if only one cooling circuit is used, for example, in a vehicle (e.g., together with an electric motor). Conventional mechanical sieves and / or filters cause a pressure drop, have only a certain filtering capacity before they need to be replaced, and offer no way to monitor the fluid quality.

[0020] The inventors have discovered that a filter effect can be improved by a conductive structure 100. Uncharged, conductive particles 150 can pass through an electrically charged structure (i.e., the conductive grid 130, such as a sieve, a sponge, etc.). By passing through the conductive grid 130, the uncharged, conductive particles 150 can become electrostatically charged. The electrostatic charging can create electrostatically charged particles 152. Furthermore, the electrostatic charging can cause a current to drop across the conductive grid 130. This current can be indicative of a number of uncharged, conductive particles 150. Accordingly, a concentration of particles dissolved in the fluid can optionally be determined based on the current flowing across the conductive grid 130. That is, the current can be measured.The measured current can be related to the particle density, particle size, and / or number of particles. Thus, fluid contamination can be determined from the measured current. The current drop across the conductive grid 130 can thus represent a measure of fluid contamination. Based on the fluid contamination, a risk of short circuit can be determined. The electrostatically charged particles 152 can then be deflected by an electric field 142 (formed, for example, by the two capacitor plates 140) as they flow through this electric field 142. The electrostatically charged particles can be redirected or collected by the deflection. For example, the deflected electrostatically charged particles 152 can disappear into a “particle sump” or be collected in a separate filter 146 (see ). Fig. 1b) are filtered out.

[0021] By arranging the conductive grid 130 within the housing 110, non-charged, conductive particles 150, which may be present within the fluid, can be electrostatically charged. This means that non-charged, conductive particles 150 can be electrostatically charged by the conductive grid 130, so that after passing through the conductive grid 130, electrostatically charged particles 152 are present. These particles can be suitably influenced by the two capacitor plates 140. The conductive structure 100 can therefore be an electrostatic device that can electrostatically charge small metallic contaminants, i.e., non-charged, conductive particles 150, and separate them from the volume flow 160.

[0022] The proposed conductive structure 100 can prevent additional pressure drop caused by filters. Furthermore, maintenance effort can be reduced. Furthermore, measuring the current drop across the conductive grid 130 provides an opportunity to check for fluid contamination. This can increase reliability.

[0023] In one embodiment, the conductive grid 130 may comprise a plurality of conductive grid elements. Individual grid elements of the plurality of conductive grid elements may be arranged one behind the other in a flow direction. The plurality of conductive grid elements 130 is Fig. 1a indicated by the dashed lines. In Fig. For example, four conductive grid elements are shown in Figure 1b, forming the conductive grid 130b. The plurality of conductive grid elements can be arranged one after the other in the direction of the volume flow 160. This can increase the probability that a non-charged, conductive particle 150 passing through the conductive grid 130 will become electrostatically charged.

[0024] In one embodiment, the conductive grid 130 may comprise openings with a width of at least 50 µm, or at least 100 µm, or at least 200 µm, or at least 400 µm, and / or a maximum of 3 mm, or a maximum of 2 mm, or a maximum of 1 mm, or a maximum of 500 µm. The width of the openings of the conductive grid 130 may, in particular, enable effective electrostatic charging of the uncharged, conductive particles 150 and prevent clogging of the conductive grid 130.

[0025] In one embodiment, the conductive structure 100b may further comprise a third capacitor plate 144b. This embodiment is shown in Fig. 1b. A longitudinal extension of the third capacitor plate 144 can be parallel to a longitudinal extension of the housing 110. Furthermore, the third capacitor plate 144 can be arranged centrally within the housing 110. A negative voltage can be applied to the third capacitor plate 144 and a positive voltage to the other two capacitor plates 140. Features that can be described with reference to Fig. 1a for the lead structure 100 can be combined with features related to Fig. 1b for the lead structure 100b, are combined and / or exchanged.

[0026] The third capacitor plate 144 can focus the electrostatically charged particles 152 centrally within the housing 110 of the guide structure 100b. To sort out the deflected (in this case focused) electrostatically charged particles 152, a separation filter 146 can be arranged centrally within the housing 110. This allows the electrostatically charged particles 152 to be separated from the fluid in a simplified manner.

[0027] In one embodiment, the conductive structure 100 can comprise a sieve. The openings of the sieve can be larger than the openings of the conductive grid 130. The sieve can filter out particles that could lead to clogging of the conductive grid. This can prevent clogging of the conductive grid 130. Since the sieve can be designed only to filter large particles, maintenance effort can be reduced compared to using a sieve without a conductive grid 130.

[0028] Fig. 2 shows a view of a fluid cooling 202. The fluid cooling 202 comprises a guide structure 100 as described with reference to Fig. 1. The conductive structure 100 comprises a housing 110, a semiconductor chip 120, an electrically conductive grid 130, and a plurality of capacitor plates 140. The fluid cooling system 202 is configured to cool the semiconductor chip 120. Within the fluid cooling system 202, a fluid can spread at a volume flow rate 160. Dissolved in the fluid can be uncharged, conductive particles 150 and electrostatically charged particles 152.

[0029] The fluid cooling system 202 includes a device 230 comprising a data processing circuit and an interface. The device can be configured to apply a first voltage to the conductive grid 130 and a second voltage to the two capacitor plates 140. The device 130 is designed to control various aspects of the fluid cooling system 202. Consequently, the device 130 can be implemented as a computer system connected to the various components of the conductive structure 100, for example, the electrically conductive grid 130.

[0030] In one embodiment, device 230 may be configured to obtain voltage data indicative of a voltage drop across electrical grid 130 and, based on the voltage data, to determine a particle concentration within conductive structure 110. This allows fluid contamination to be determined in a simplified manner.

[0031] As described above, the electrostatic charging of the uncharged, conductive particles 150 can cause a current to drop across the conductive grid 130. The voltage data can be indicative of the current drop across the conductive grid 130. This means that the device 230 can obtain information about the current caused by the electrostatic charging of the uncharged, conductive particles 150 as they pass through the electrically conductive grid 130. For example, the device 230 can read a voltage directly at an electrical contact of the conductive grid 130. Alternatively, the device 230 can receive information about the voltage, i.e., the device 230 can receive the voltage data.

[0032] Based on the voltage data, device 230 can determine a particle concentration within conductive structure 110. This allows fluid cooling system 202 to simplify the determination of a particle concentration within the fluid. This can improve the operation of fluid cooling system 202.

[0033] In one embodiment, the fluid cooling system 202 can be connected to cool a radiator, an electric motor, a battery, and / or a transmission. Particularly when the fluid cooling system 202 is operated in combination with other components, contamination of the fluid can be increased. In this case, separation of conductive particles by the conductive structure 110 can be particularly advantageous.

[0034] As in Fig. 2, the interface 232 may be coupled to the respective data processing circuitry 234 of the device 230. In examples, the device 230 may be implemented by one or more processing units, one or more processing devices, any means of processing, such as a processor, a computer, or a programmable hardware component operable with appropriately adapted software. Likewise, the described functions of the data processing circuitry 234 may also be implemented in software, which is then executed on one or more programmable hardware components. Such hardware components may be a general-purpose processor, a digital signal processor (DSP), a microcontroller, etc.The data processing circuitry 234 may be capable of controlling the interface 232 such that any data transfer that occurs over the interface 232 and / or any interaction that the interface 232 may be involved in may be controlled by the data processing circuitry 234.

[0035] In one embodiment, the device 230 may include a memory 236 and at least one data processing circuit 234 operatively coupled to the memory 236 and configured to perform the method described below.

[0036] In examples, interface 232 may correspond to any means for obtaining, receiving, transmitting, or providing analog or digital signals or information, e.g., any terminal, contact, pin, register, input terminal, output terminal, conductor, trace, etc., that enables the provision or receipt of a signal or information. Interface 232 may be wireless or wired and may be configured to communicate with other internal or external components, e.g., to send or receive signals or information.

[0037] The device 230 may be a computer, a processor, a controller, a field-programmable logic array (FPLA), a field-programmable gate array (FPGA), a graphics processing unit (GPU), an application-specific integrated circuit (ASIC), an integrated circuit (IC), or a system-on-a-chip (SoC).

[0038] Fig. 3 shows an embodiment of a vehicle 300. The vehicle 300 includes a guide structure 320 as described above, for example with reference to Fig. 1, or a fluid cooling 310 as described above, for example with reference to Fig. 2. For example, the conductive structure 320 can be part of the fluid cooling 310. Reference symbol 100 Lead Structure 110 housings 120 semiconductor chips 122 circuit boards 130 conductive grid 140 capacitor plate 142 electric field 144 Capacitor plate 146 separation filters 150 uncharged, conductive particles 152 electrostatically charged particles 160 volume flow 230 device 232 Data processing circuit 234 Interface 236 memory 300 vehicles 310 fluid cooling 320 Lead structure

Claims

[1] A conductive structure (100; 100b) for fluid cooling for a semiconductor chip, comprising: a housing (110) for conducting a fluid; a semiconductor chip (120) arranged in the housing (110); a conductive grid (130) arranged in the housing (110); an electrical contact for electrically contacting the conductive grid (130); and two capacitor plates (140), wherein the two capacitor plates (140) comprise an electrical contact for applying an electrical voltage. [2] The conductive structure (100; 100b) according to claim 1, wherein the conductive grid (130) comprises a plurality of conductive grid elements, wherein individual grid elements of the plurality of conductive grid elements are arranged one behind the other in a flow direction. [3] The conductive structure (100; 100b) according to any one of the preceding claims, wherein the conductive grid (130) comprises openings with a width of at least 50 µm and a maximum of 3 mm. [4] The conductive structure (100; 100b) according to any one of the preceding claims, further comprising a third capacitor plate, wherein a longitudinal extent of the third capacitor plate is parallel to a longitudinal extent of the housing (110) and the third capacitor plate is arranged centrally within the housing (110). [5] The conductive structure (100; 100b) according to any one of the preceding claims, further comprising a screen, wherein openings of the screen are larger than openings of the conductive grid (130). [6] The conductive structure (100; 100b) according to any one of the preceding claims, wherein the conductive grid (130) comprises or consists of copper. [7] A fluid cooling system comprising a conductive structure (100; 100b) according to any one of the preceding claims; and a device (230) comprising a data processing circuit (234) and an interface (232), wherein the device (230) is configured to apply a first voltage to the conductive grid (130) and a second voltage to the two capacitor plates (140). [8] The fluid cooling, wherein the device (230) is further configured to obtain voltage data indicative of a voltage drop across the electrically conductive grid (130); and to determine a particle concentration within the conductive structure (100; 100b) based on the voltage data. [9] The fluid cooling, wherein the fluid cooling is connected to at least one of a radiator, an electric motor, a battery and a transmission for cooling. [10] A vehicle (300) comprising: a guide structure (320) according to any one of claims 1-6 or a fluid cooling (310) according to any one of claims 7-9.

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