DE102004062635A1 - Electrical assembly with spacers between multiple circuit carriers - Google Patents

Abstract

The invention relates to an electrical assembly (1), comprising a circuit carrier (2, 23) with at least one electrical circuit (21) having at least one electrical component (22, 221) arranged on a surface section (237) of the circuit carrier, and at least a further circuit carrier (3, 33) with at least one further electrical circuit (31), wherein the circuit carrier and the further circuit carrier are arranged in such a way that the circuit and the further circuit via at least one electrical connection line (5) are electrically connected to each other in that the component arranged on the surface section of the circuit carrier is arranged opposite the further circuit carrier and the component and the further circuit carrier are spaced apart from one another by means of at least one spacer (4). The result is an electrical assembly with a compact, space-saving design. Particularly, the invention is suitable for the electrical contacting of a power semiconductor module, in which the on the circuit carrier, for. B. DCB substrate, arranged power semiconductor devices are contacted planar and large area. Electrical connection points (235) can easily be realized on the DCB substrate, which are soldered to electrical connection points (331) of the further circuit carrier, for example a PCB substrate, via the spacers. The ...

Description

The The invention relates to an electrical assembly with a plurality of circuit carriers, the spaced apart by means of spacers.

The electrical assembly has, for example, a circuit carrier (substrate) on, with the help of a power semiconductor module is realized. On the circuit carrier of the power semiconductor module are power semiconductor components applied and electrically connected together to form an electrical circuit connected. For electrically contacting the contacts of the power semiconductor components become common Bond wires used. For electrical insulation, the bonding wires and the Power semiconductor components poured into a potting compound. The potting compound is for example silicone. The potted power semiconductor module is in a housing arranged.

A Alternative for contacting via bonding wires is For example, from WO 03/030247 A2 known. Here are the contact surfaces the on a circuit carrier arranged power semiconductor devices contacted over a large area and planar. For contacting, an insulating film is applied to the power semiconductor components laminated. The insulating film is for example a plastic film based on polyimide or epoxy. By creating windows in the Insulation foil become the contact surfaces of the power semiconductor components exposed. Subsequently, the contact surfaces by deposition of metal on the contact surfaces and electrically contacted on areas of the insulating film.

In both cases described are for electrical contacting of the respective circuit from the outside forth or to the outside towards the respective circuit boards electrical connection points present, which contacted by means of a s so-called "lead frame" electrically are. about a "lead Frame "becomes the Circuit of the power semiconductor module with at least one further, external circuit electrically connected

task The present invention is to provide a compact structure of a specify electrical assembly with at least two circuit carriers.

to solution The object is an electrical assembly specified, comprising a circuit carrier with at least one electrical circuit, the at least one on a surface section of the circuit board arranged electrical component, and at least one further circuit carrier with at least one further electrical circuit, wherein the circuit carrier and the other circuit carrier such are arranged together, that the circuit and the other Circuit over at least one electrical connection line electrically conductive with each other are connected, arranged on the surface portion of the circuit substrate component the further circuit carrier opposite is arranged and the device and the other circuit carrier with Help at least one spacer are spaced from each other.

Of the Circuit and the other circuit are via the connecting line interconnected to a complete circuit. The circuit carrier and the additional circuit carrier have corresponding connection points to form a complete circuit on. By arranging the circuit carrier to each other the circuits at the connection points electrically conductive with each other connected.

With this measure can be on "Lead Frames "to the electric Connection of the circuit with an external circuit omitted become. At the same time is for it ensured that the component and the other circuit carrier from each other are spaced, so do not touch each other. By the arrangement results itself from the circuit board and from the other circuit carrier limited space in which the device is arranged. It results in an assembly with a compact and space-saving design. In addition, the device is protected in the space.

According to one special embodiment is the component of the electrical circuit against at least one component (further electrical component) the further electrical circuit of the further circuit carrier electrically isolated. The electrical connection of the circuits to each other takes place only via the intended electrical connection points. An uncontrolled Short circuit between the component and the component of the other Circuit is excluded.

For electrical insulation, it may be sufficient if the component and the further circuit or the component of the further circuit do not touch each other. For electrical insulation, a potting compound may be present, with which the gap between the circuit carriers is at least partially filled, in which the device is located. The potting compound has, for example, silicone. In a particular embodiment, however, at least one of the component and / or mindes for electrical insulation least one on the component of the further electrical circuit laminated insulating film available. It can be dispensed with the potting compound. It is also conceivable that the insulation film and the potting compound are used together. It is particularly elegant to use a circuit carrier in which, as described above, the electrical contacting of the applied components is produced by means of an insulating film. The insulating film is configured (film thickness, film material, etc.) and laminates that the electrical insulation is ensured to components of the other circuit substrate.

In In a particular embodiment, the spacer has the electrical Connection line on. For example, the spacer consists from an electrically conductive Material. The spacer comes with an electrical connection point of the circuit board and a further electrical connection point of the further circuit carrier electrically and mechanically contacted. For this purpose, the electrical connection line according to a particular embodiment one from the group solder and / or conductive adhesive selected electrically conductive Connecting means on. By the electrically conductive connection means become the circuit carriers mechanically fixed to each other. At the same time creates an electrical Connection between the circuits. It results in a compact and mechanically stable construction.

Of the Spacer can be arbitrarily shaped. For example, points the spacer is a pillar shape on. It is also conceivable, in particular, for the spacer to be curved or is angled. The spacer has a curvature. Preferably the spacer is arranged such that a possible greater Interspace between the circuit carriers for receiving the electrical Component is present. This is achieved, for example, by that part of the curved one Spacer away from the electrical component.

The Assembly may have a single spacer between the circuit carriers. In a particular embodiment is a plurality of spacers available. This results in a particularly robust construction.

Furthermore can by several spacers several electrical connection lines be realized. This results in an electrical assembly with a very high integration density.

When circuit support and further circuit carriers come any inorganic or organic circuit carriers in question. The circuit carrier can be single-layered or multi-layered. In particular, the circuit carrier and / or the further circuit carriers a DCB (Direct Copper Bonding) substrate or a PCB (Printed Circuit Board) substrate. For example the circuit is realized on a DCB substrate. The further circuit on the other hand, on a PCB substrate.

The electrical component of the circuit carrier can be any active or passive electrical component. According to a particular embodiment the device is a semiconductor device. The semiconductor device For example, an SMD (Surface Mounted Device) device of the Circuit carrier. In a particular embodiment, the semiconductor device is a Power semiconductor device is. The power semiconductor device may be a MOSFET, IGBT, bipolar transistor or a diode. Of the circuit support is part of a power semiconductor module. It is suitable in particular the planar and large-area contacting described above the power semiconductor devices. By laminating the Insulating foil used for electrical contacting can in a simple way for an efficient electrical insulation of the components and the components the further circuit of the further circuit carrier provided become.

Preferably is the insulating film on the power semiconductor device and the circuit carrier applied that a surface contour of the power semiconductor component and / or a surface contour of the circuit board in a surface contour the insulating film are shown, the power semiconductor device and / or the circuit carrier has turned away. The insulation film can be glued on. Preferably is the insulating film on the power semiconductor device and on the circuit carrier laminated. The lamination preferably takes place without adhesive. The insulation film is not glued on. For this purpose, the lamination takes place for example, applying a vacuum, with a particular intimate and firm contact between the power semiconductor device and the insulating film or the circuit carrier and the insulating film arises.

Around an efficient electrical insulation with the help of the insulating foil to achieve this is necessary film thickness (Film thickness) of the insulation film selected. The necessary film thickness depends on different ones Factors from, for example, the insulating material of the insulation film or the conditions under which the assembly is operated. It has proved to be advantageous if the insulation film one in the range of from 50 microns up to and including 500 microns and in particular has a film thickness selected from the range of 100 μm to 300 μm inclusive.

Around to achieve a necessary insulating effect of the insulating film, can be a single, as possible thick insulation film are laminated. A corresponding insulation effect but also with several, one above the other stacked, thinner Insulation films are achieved.

• – Mit der Erfindung ist eine kompakte Baugruppe aus mit zwei Schaltungsträgern zugänglich.
• – Auf die Verwendung eines „Lead Frames" zur elektrischen Verbindung des Stromkreises mit einem externen Stromkreis kann verzichtet werden.
• – Bei Verwendung von mehreren Abstandshaltern, die auch als Verbindungsleitungen fungieren, resultiert eine hohe Integrationsdichte.
• – Durch die Verwendung einer auflaminierten Isolationsfolie zur elektrischen Isolierung des Bauteils des Schaltungsträgers kann für eine einfache und effiziente elektrische Isolierung des Bauelements gesorgt werden. Auf eine zusätzliche Isolierung durch Silikonverguss kann verzichtet werden.

In summary, the invention provides the following essential advantages:

• - With the invention, a compact assembly is accessible from two circuit carriers.
• - The use of a "lead frame" for electrical connection of the circuit to an external circuit can be dispensed with.
• - When using several spacers, which also act as connecting lines, results in a high integration density.
• - By using a laminated insulation film for electrical insulation of the component of the circuit substrate can be ensured for a simple and efficient electrical insulation of the device. An additional insulation by Silikonverguss can be dispensed with.

Based an exemplary embodiments and the associated Figures, the invention is described in more detail below. The figures are schematic and do not represent true to scale illustrations represents.

1 shows an assembly in a lateral cross-section.

2 shows the assembly in supervision.

3 shows a section of the assembly in a lateral cross-section.

According to the embodiment, the assembly 1 a circuit carrier 2 with a circuit 21 and another circuit carrier 3 with another circuit 31 on ( 1 and 2 ).

The circuit carrier 2 is a DCB substrate 23 , The DCB substrate 23 has a carrier layer 231 made of aluminum oxide and applied on both sides electrical power layers 232 and 233 on. The conductor layer 232 is part of the circuit 21 of the circuit board 2 ( 3 ).

On a surface section 237 of the DCB substrate 23 passing through the conductor layer 232 is given, is an electrical component 22 in the form of a power semiconductor device 221 soldered. The result is the solder layer 224 , The power semiconductor device 221 is soldered such that one from the DCB substrate 23 groundbreaking contact surface 222 of the line semiconductor device 221 results. For large-area, planar electrical contacting of the contact surface 222 of the power semiconductor device 221 is an insulation film 24 auflaminert under vacuum. The insulation film 24 is doing so on the DCB substrate 23 and the power semiconductor devices 221 laminated that a surface contour 223 of the power semiconductor device 221 and a surface contour 234 of the substrate 23 in a surface contour 241 the insulation film 24 Pictured is the DCB substrate 23 and the power semiconductor device 221 has turned away.

Through a window 242 the insulation film 24 is the contact or the contact surface 222 of the power semiconductor device 221 electrically contacted. This will be the window 242 in the insulation film 24 opened by laser ablation. The planar electrical contacting of the contact surface 222 is through a multi-layered deposition 225 generated by electrically conductive materials.

The additional circuit carrier 3 is a PCB substrate 33 , On the PCB substrate 33 is the other circuit 31 realized, consisting of various, not shown electrical components 32 consists.

The circuit carrier 2 and the other circuit carrier 3 are about a variety of curved spacers 4 interconnected and spaced apart. The circuit carrier 2 and 3 are arranged in such a way to each other that on the surface portion of the circuit substrate 2 arranged power semiconductor device 221 the other circuit carrier 3 is opposite. It is a gap 6 between the circuit boards 2 and 3 present in which the power semiconductor device 221 located.

At least one of the spacers 4 is as an electrical connection line 5 between the circuits 21 and 31 the circuit carrier is formed. For electrical connection is the connecting line 5 at the connection points 235 of the circuit board 2 and at the other connection points 331 the further circuit carrier 3 soldered. It is always a layer of solder 41 between the respective connecting line 5 and the corresponding connection point 235 of the circuit board 2 or the corresponding connection point 331 the further circuit carrier 3 available.

Claims (9)

Electrical assembly ( 1 ), comprising - a circuit carrier ( 2 . 23 ) with at least one electrical circuit ( 21 ) that at least a on a surface section ( 237 ) of the circuit carrier ( 2 . 23 ) arranged electrical component ( 22 . 221 ), and - at least one further circuit carrier ( 3 . 33 ) with at least one further electrical circuit ( 31 ), wherein - the circuit carrier ( 2 . 23 ) and the further circuit carrier ( 3 . 33 ) are arranged in such a way that - the circuit ( 21 ) and the further circuit ( 31 ) via at least one electrical connection line ( 5 ) are electrically conductively connected to each other, - that on the surface portion ( 237 ) of the circuit carrier ( 2 . 21 ) arranged component ( 22 . 21 ) the further circuit carrier ( 3 . 33 ) is arranged opposite and - the component ( 22 . 221 ) and the further circuit carrier ( 3 . 33 ) by means of at least one spacer ( 4 ) are spaced from each other. An assembly according to claim 1, wherein the component ( 22 . 221 ) of the electrical circuit ( 21 ) against at least one component ( 32 ) of the further electrical circuit ( 31 ) of the further circuit carrier ( 3 . 33 ) is electrically isolated. An assembly according to claim 2, wherein for electrical insulation at least one on the component ( 22 . 221 ) and / or on the component ( 32 ) of the further electrical circuit ( 31 ) laminated insulation film ( 24 ) is available. Assembly according to one of claims 1 to 3, wherein the spacer ( 4 ) the electrical connection line ( 5 ) having. An assembly according to any one of claims 1 to 4, wherein a plurality of spacers ( 4 ) is available. Assembly according to one of claims 1 to 5, wherein the electrical connection line ( 5 ) has an electrically conductive connecting means selected from the group solder and / or conductive adhesive. Assembly according to one of claims 1 to 6, wherein the circuit carrier and / or the additional circuit carrier a DCB substrate or a PCB substrate. Assembly according to one of claims 1 to 7, wherein the component of the circuit is a semiconductor device. An assembly according to claim 8, wherein the semiconductor device is a power semiconductor device ( 221 ).