Power semiconductor module with a printing device

Abstract

A power semiconductor module is presented, comprising a substrate with a normal direction, a plurality of conductor tracks arranged on a substrate base body of the substrate, a power semiconductor component arranged on a conductor track, an internal connection device, a pressure device formed with a rigid base body with a main surface facing the substrate and an insulating material body, formed with an insulating material base body and knob bodies projecting away from it in the direction of the substrate, said knob bodies being arranged in associated recesses in the base body, an insulating material being arranged between the main surface of the base body and the substrate including the connection device,wherein a first surface of a first knob body designed as a pressure body, facing the substrate, is in direct contact with the connecting device or with the substrate, and wherein a second surface of a second knob body designed as an additional body, facing the substrate, is in direct contact exclusively with the insulating material, but not with the connecting device and also not with the substrate,

Description

The invention describes a power semiconductor module having a substrate with a plurality of conductor tracks arranged on a substrate base body of the substrate, having a power semiconductor component arranged on a conductor track, having an internal connecting device, having a printing device.DE 10 2021 115 926 B3 discloses a printing device for the indirect or direct introduction of pressure onto power semiconductor components of a power semiconductor module, having a pressure plate, having a pressure nub element which is formed from an elastic material and has a pressure nub plate and pressure nubs projecting therefrom, and having a receptacle device for receiving the pressure nub element, which receptacle device has a base plate provided with recesses, the recesses running through the base plate, the pressure nub plate being arranged on the base plate and the pressure nubes running through the recesses and projecting beyond this main side of the base plate on the main side of the base plate facing away from the pressure nub plate, the pressure nub plate being arranged between the pressure plate and the base plate.DE 10 2016 123 113 B3 discloses a printing device, formed with a base body, which has a plurality of receiving devices for printing bodies, wherein the respective printing body is formed with a first, rigid partial body and a second, spring-elastic partial body, wherein the printing bodies are arranged in the receiving devices of the base body by means of a reversible connection and the respective second partial body protrudes from the associated first partial body in the direction away from the base body. In this case, one or more first sub-bodies can also each have more than one second sub-body.Furthermore, a power electronic switching device with such a printing device and an arrangement with such a switching device are disclosed.DE 10 2014 115 565 B3 discloses a method for producing a power electronic switching device having a substrate, a power semiconductor component arranged thereon, having a connecting device, and having connection devices, has the following steps: A) providing the substrate with an insulation layer and having conductor tracks electrically insulated from one another, wherein a power semiconductor component is arranged on a conductor track and is connected to the conductor track in a materially bonded manner; B) arranging the connecting device in the form of a film stack; C) arranging a thin insulation layer, which follows a surface contour of the connecting device and is resistant to pressure and temperature and also prevents moisture, having a covering section on the connecting device and having an overlapping section which overlaps the connecting device peripherally on all sides and covers the substrate in a peripheral contact region; D) Materially bonding the connecting device to the substrate, whereby the switching device is connected internally in the correct circuit by means of the connecting device; E) Connecting the covering section of the insulation layer to the connecting device; F) Connecting the overlapping section of the insulation layer to the contact region of the substrate.Proceeding from the prior art and the need to arrange an insulating material suitably between the printing device and the substrate of a power semiconductor module, the object of the invention is to configure the printing device in an improved manner.This object is achieved according to the invention by a power semiconductor module having a substrate with a normal direction, having a plurality of conductor tracks arranged on a substrate base body of the substrate, having a power semiconductor component arranged on a conductor track, having an internal connecting device, having a pressure device formed with a rigid base body having a main surface facing the substrate and having an insulating body formed with an insulating base body and knob bodies protruding away from the latter in the direction of the substrate, wherein these knob bodies are arranged in associated recesses of the base body, wherein an insulating material is arranged between the main surface of the base body and the substrate together with the connecting device, wherein a first surface, facing the substrate, of a first knob body configured as a pressure body is in direct contact with the connecting device or with the substrate, and wherein a second surface, facing the substrate, of a second knob body configured as an additional body is in direct contact exclusively with the insulating material, but not with the connecting device and also not with the substrate.The term "direct contact" is understood here and below to mean that there is no further object and also no gap or empty space between the two contact partners.It can of course be advantageous if, upon introduction of pressure by means of the pressure device, i.e. in particular naturally during operation, the first knob body is deformed and the second knob body is formed to be undeformed.It can be preferred if the insulating material base body is arranged in a main recess of the base body.It can be advantageous if the connecting device is formed from a first electrically conductive foil and a first electrically insulating foil, wherein the electrically conductive foil preferably forms a plurality of foil conductor tracks. In this case, it can be particularly advantageous if the connecting device has an upper side, as viewed in the normal direction, on which the first knob body presses and is deformed in the process. As an alternative to this, other connecting devices customary in the art, such as wire or tape bond connections, can also be used. This is usually accompanied by the pressure on the substrate, not on the connecting device.It can be preferred if the surface of a first knob body protrudes from the associated recess in the negative normal direction.It can likewise be preferred if the surface of a second knob body does not protrude from the associated recess in the negative normal direction, but is arranged set back in the normal direction with respect to the main surface of the main body.It can also be preferred if the knob body is arranged in alignment with an intermediate space between two adjacent conductor tracks in the normal direction.In addition, it can be advantageous if a metal body is arranged on the side of the insulating material base body facing away from the substrate.In principle, it may be preferred if the insulating body is formed from the material group of the elastomers, in particular that of the silicone rubbers, having a first Shore A hardness of between 30 and 90 and in particular between 60 and 70, or from the material group of the plastic foams, in particular from silicone foam having a compressive force according to ASTM D1056 of between 25 kPa and 250 kPa and in particular between 100 kPa and 150 kPa.It is understood that the features and configurations of the power semiconductor module mentioned above and below can be realized individually or in any combinations in order to achieve improvements. In particular, the features mentioned above and explained here or in the following can be used not only in the combinations indicated, but also in other non-exclusive combinations or alone, without departing from the scope of the present invention.Further explanations of the invention, advantageous details and features will become apparent from the following description of the exemplary embodiments of the invention schematically illustrated in FIGS. 1 to 6 or of respective parts thereof. FIG. 1 schematically shows a first configuration of a power semiconductor module according to the invention in an exploded illustration. FIG. 2 shows this power semiconductor module in the mounted state. FIG. 3 shows selected components of this power semiconductor module. FIG. 4 shows the second configuration of a power semiconductor module according to the invention in a three-dimensional exploded illustration. FIG. 5 shows the pressure element of the second embodiment of a power semiconductor module according to the invention in a three-dimensional sectional view. FIG. 6 schematically shows a third configuration of a power semiconductor module according to the invention.FIG. 1 schematically shows a first configuration of a power semiconductor module 1 according to the invention in an exploded illustration in a side view arranged on a cooling device, in this case configured as a liquid cooling device 14. FIG. 2 shows this power semiconductor module in the mounted state, while FIG. 3 shows selected components of this power semiconductor module.A substrate 2 is shown which is generally customary in the art and has a ceramic body 20 and conductor tracks 22, 24, 26 which are arranged thereon and are each electrically insulated from one another and which have different potentials, in particular load potentials, but also auxiliary, in particular control and measurement potentials, of the power semiconductor module during operation of the power semiconductor module. Three conductor tracks 22, 24, 26 for load potentials, as are typical for a power semiconductor module in half-bridge topology, are specifically shown here.A power semiconductor component 5 is arranged on a first and a second conductor track 22, 26, purely by way of example, which can be embodied as an individual switch, by way of example as a MOS-FET, or as an IGBT with a power diode connected in antiparallel, in each case in a customary manner in the art. The power semiconductor components 5, more precisely their first contact surface, are electrically conductively connected to the first conductor tracks 22 in a materially bonded manner, preferably by means of a pressure sintering connection 4.The internal connections of the power semiconductor module 1 are formed by means of a connecting device 3 from a foil composite as a flexible foil stack which alternately has electrically conductive foils 30, 34 and electrically insulating foils 32. Here, the film composite has exactly two conductive films and an insulating film arranged therebetween. In particular, the conductive foils 30, 34 of the connecting device 3 are structured in themselves and thus form foil conductor tracks which are electrically insulated from one another. These foil conductor tracks connect in particular the respective power semiconductor component 5, more precisely its second contact surface on the side facing away from the substrate 2, to a conductor track of the substrate 2.For external electrical connection, the power-electronic power semiconductor module 1 has load and auxiliary connection elements, not shown.The described power semiconductor module, more precisely its substrate 2, is arranged on a liquid cooling device 14, the surface of which is covered with a heat-conducting layer 140. Power semiconductor modules according to the invention can of course have further components according to the prior art which are not explicitly described.Furthermore, the pressure device 6 of the power semiconductor module is shown. This pressure device 6 has a rigid base body 7 and an insulating body 60, the insulating body 60 being formed from a silicone rubber having a first Shore A hardness of 60. The base body itself has a main surface 700 facing the substrate 2 and a main recess 768 on the side facing away from the substrate 2.The insulating body 60 has an insulating body 68 and knob bodies 62, 64, 66 protruding away from the latter in the direction of the substrate 2. The base body itself is arranged in this main recess 768. The knob bodies are arranged in associated recesses 762, 764, 766 of the base body 7. These recesses extend from the main recess of the base body through it and through the main surface 700. Three embodiments of knob bodies 62, 64, 66 are shown here. Two first knob bodies 62, which are designed as pressure bodies, cf. FIGS. 2 and 3, are designed and provided after the complete formation and in particular during operation of the power semiconductor module for their respective first surface 620 facing the substrate 2 to be in direct mechanical contact with the connecting device 3, more precisely with its upper side 340.Two second knob bodies 64, 66, which are designed as additional bodies, cf. FIGS. 2 and 3, are designed and provided for this purpose, after the complete formation and in particular during operation of the power semiconductor module, for their respective second surface 640, 660 facing the substrate 2 to be in direct mechanical contact neither with the connecting device 3 nor with the substrate 2.Furthermore, explicitly illustrated in FIG. 2, an insulating material 8 is arranged in the interspace between the main surface 700 of the base body 7 and the substrate 2 together with the connecting device 3. The second surfaces 640, 660 of the two second knob bodies 64, 66, i.e. the additional body, facing the substrate 2, are in direct contact exclusively with the insulating material 8.The power semiconductor module furthermore has a pressure introduction device which is customary in the art and is supported against the liquid cooling device 14, not illustrated, and introduces pressure 70 onto the insulating material base body 68. This pressure 70 is transmitted directly to the film composite as partial pressure 74 by means of the first knob bodies, cf. also FIG. 2.As a result of this described pressure introduction and illustrated in FIG. 2, the first knob body 62 is deformed with respect to the state illustrated in FIG. 1 without pressure introduction. In contrast, the second knob bodies 64, 66 are formed in an unformed manner even when pressure is introduced.One of the two second knob bodies 64, shown on the left, protrudes beyond the main surface 700 of the main body 7 in the negative normal direction, i.e. toward the substrate 2. This second knob body 64 is arranged in the normal direction N in alignment with an intermediate space 224 between two conductor tracks of the substrate 2.The second knob body 66, shown on the right, does not protrude from the base body 7, but is set back in the normal direction N with respect to the main surface 700.FIG. 4 shows the second configuration of a power semiconductor module 1 according to the invention in a three-dimensional exploded illustration, while FIG. 5 shows the pressure element of this second configuration in a three-dimensional sectional view. The power semiconductor module has a frame-like housing 10 with two load connection elements on one narrow side of the housing and a further load connection element on the opposite narrow side. The auxiliary connection elements are arranged on a longitudinal side and are designed as press pin elements.The frame-like housing 10 encloses the substrate 2 of the power semiconductor module 1, wherein the substrate has the components already described with reference to FIG. 1. Also shown in FIG. 4 is the printing device which has a further recess aligned with a substrate recess. This substrate recess and the further recess are provided and designed to accommodate a pressure introduction device which is customary in the art and is not illustrated.FIG. 5 shows the first and second knob bodies of this embodiment, which functionally correspond to those described with reference to FIGS. 1 to 3. In addition, a metal body 9 is arranged here on the side of the insulating material base body 60 facing away from the substrate 2, said metal body serving for the pressure distribution onto the insulating material base body 60 and thereby onto the first knob bodies 62.FIG. 6 schematically shows a third configuration of a power semiconductor module 1 according to the invention. Consequently, the first surface of the first knob body presses on the substrate, in this embodiment on a conductor track of the substrate 2. in addition, purely by way of example, the two second knob bodies 64 protrude from the main surface 700 to different extents.

Claims

Power semiconductor module (1) having a substrate (2) with a normal direction (N), having a plurality of insulated conductor tracks (22, 24, 26) arranged on a substrate base body (20) of the substrate (2), having a power semiconductor component (5) arranged on a conductor track (22), having an internal connecting device (3), having a pressure device (6) formed with a rigid base body (7) with a main surface (700) facing the substrate (2), and having an insulating body (60) formed with an insulating base body (68) and knob bodies (62, 64, 66) projecting away from the latter in the direction of the substrate (2), wherein these knob bodies are arranged in associated recesses (762, 764, 766) of the base body (7), wherein an insulating material (8) is arranged between the main surface (700) of the base body (7) and the substrate (2) together with the connecting device (3), wherein a first surface (620), facing the substrate (2), of a first knob body (62), configured as a pressure body, is in direct contact with the connecting device (3) or with the substrate (2), and wherein a second surface (640, 660), facing the substrate (2), of a second knob body (64, 66), configured as an additional body, is in direct contact exclusively with the insulating material (8), but not with the connecting device (3) and also not with the substrate (2).Power semiconductor module according to Claim 1, wherein, when pressure is introduced by means of the pressure device (6), the first knob body (62) is deformed and the second knob body (64, 66) is formed in an undeformed manner.Power semiconductor module according to one of the preceding claims, wherein the insulating material base body (68) is arranged in a main recess (768) of the base body (7).Power semiconductor module according to one of the preceding claims, wherein the connecting device (3) is formed from a first electrically conductive foil (30) and a first electrically insulating foil (32), wherein the electrically conductive foil (30) preferably forms a plurality of foil conductor tracks.Power semiconductor module according to Claim 4, wherein the connecting device (3) has an upper side (340), as viewed in the normal direction (N), on which the first knob body (62) presses and is deformed in the process.Power semiconductor module according to one of the preceding claims, wherein the surface (620, 640) of a first knob body (62, 64) protrudes from the associated recess (762, 764) in the negative normal direction (N).Power semiconductor module according to one of the preceding claims, wherein the surface (660) of a second knob body (66) does not protrude from the associated recess (766) in the negative normal direction (N), but is arranged set back in the normal direction (N) with respect to the main surface (700) of the main body (7).Power semiconductor module according to one of the preceding claims, wherein the second knob body (64) is arranged in alignment in the normal direction (N) with an intermediate space (224) between two adjacent conductor tracks (22, 24).Power semiconductor module according to one of the preceding claims, wherein a metal body (9) is arranged on the side of the insulating material base body (60) facing away from the substrate (2).Power semiconductor module according to one of the preceding claims, wherein the insulating body (60) is formed from the material group of the elastomers, in particular that of the silicone rubbers, having a first Shore A hardness of between 30 and 90 and in particular between 60 and 70, or from the material group of the plastic foams, in particular from silicone foam having a compressive force according to ASTM D1056 of between 25 kPa and 250 kPa and in particular between 100 kPa and 150 kPa.

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