DE4304654A1 - Method and arrangement for the temperature regulation of a component - Google Patents

Abstract

The invention relates to a method and an arrangement for the temperature regulation of a component, in particular a component arranged on a populated printed circuit board. In this case, there is fitted in the substrate (printed circuit board), underneath said component, a (semiconductor) cooling element, which is preferably designed as a Peltier element and effects a control and/or regulation of the temperature of the component when a direct current flows. This makes possible, by way of advantage, a specific, discrete temperature regulation of components.

Description

The invention relates to a method and an arrangement for tempering a component according to the generic terms of claims 1 and 5.

The invention particularly relates to the cooling of construction elements used in electrical engineering to manufacture Circuit arrangements are used. Such circuit arrangements contain active and / or passive electrical Components generally attached to a substrate be classified. With increasing shrinkage of the components the possible packing density (number of Components per unit area) on the substrate. With too  increasing packing density generally also increases the annoying heat loss when operating the scarf arrangement arises. Often are on the substrate individual components attached, which a lot Heat loss and / or a particularly high annoying temperature generate ratur.

For cooling, that is, for dissipative loss heat, such circuit arrangements are a variety of methods and / or arrangements known. For example is cooling with the help of an air and / or gas flow possible. Such a procedure has in particular the after part that generally only a large-scale cooling is possible. Individual components that do a lot Generate heat loss and / or a particularly high temperature Generate ratur are with such a method everyone if with a high technical effort, e.g. B. a spe central nozzle system, coolable.

Alternatively and / or as a supplement to this procedure it is possible to connect individual components in a thermal contact to bring a heat sink. The latter generally have mean a relatively large surface for deriving the Heat loss, are therefore large-volume and therefore cause a reduction from the electrical point of view is possible pack density.

It is also possible to use a substrate that good thermal conductivity and high electrical Insulation ability. Such substrates exist e.g. B. from a metallic core, for. B. a metallic Sheet metal with an electrically iso on one or both sides  lier layer, z. B. plastic or glass or ceramic, is applied. Such coating materials are disadvantageous liger inexpensive, have a high spec cal weight and are particularly unsuitable when le only individual components must be cooled.

The invention has for its object a genus suit and a generic arrangement ben, which in particular an inexpensive and reliable cooling of individual components, which almost bige substrates can be arranged, allow.

This problem is solved by the in the characterizing Parts of claims 1 and 5 specified features. Advantageous refinements and / or further developments are the dependent claims.

A first advantage of the invention is that a simple mechanical separation of a heat sink from the cooling component is possible.

A second advantage is that the substrate with known methods and arrangements with components can be equipped, so that it is neglected at most visible changes are required.

Further advantages can be found in the description below acceptable.

The invention is based on an embodiment example and with reference to a schematic associated figure explained in more detail.  

The figure shows a substrate 1 , e.g. B. a so-called Lei terplatte, which contains several interconnect levels. Such a plate-shaped substrate z. B. a thickness from egg nem range from about 1.5 mm to about 2.5 mm. It is an alternative layer structure of metallic Lei terbahnebenen and electrically insulating layers, for. B. plastic layers available. Such electrically insulating layers generally have poor thermal conductivity, so that the substrate 1 as a whole has poor thermal conductivity in the direction of its surface normal. Such a substrate 1 has two mutually parallel surfaces, the so-called B-side (component side), on which the number of electronic active and / or passive components 3 are arranged, for. B. by soldering and / or electrically conductive adhesive connections, and the so-called L-side, which is the side facing away from the B-side and on which electrical conductor tracks can be arranged in the form of a printed circuit. In many cases, conductor tracks are also arranged on the B side. The components 3 , z. B. so-called SMD components ("Surface mounted devi ces") are either only connected to the conductor tracks on the B side and / or with the help of so-called through contacts alternatively and / or additionally with conductor tracks within the substrate and / or on the L side. The figure shows a heat-generating active and / or passive component 3 , for. B. a semiconductor component or a so-called hybrid circuit, which itself consists of active and / or passive components. In the figure, the electrical connections of the component 3 , for. B. SMD connectors or metallic pins, not Darge provides. Below the component 3 , preferably at those locations that generate the majority of the heat, there is an opening 2 , z. B. a through hole with a diameter of about 1.3 mm in the substrate. 1 The diameter of the bore can be chosen almost arbitrarily over a wide range and can therefore be adapted to the diameter of the cooling element 4 . In this breakthrough 2 , an electrothermal cooling element 4 is now inserted and electrically conductive, for. B. via solder and / or adhesive connections 5 , with the associated conductor rail connections 6 , 7 connected. The cooling element 4 is preferably a semiconductor device formed as a Peltier element with at least one PN junction. As a semi-conductor material z. B. selenium telluride, which is doped with antimony (p-doping) and bismuth (n-doping). The length and the arrangement of the cooling element 4 in the substrate 1 are preferably chosen so that the cooling element 4 touches the component 3 to be cooled. A particularly good heat transfer occurs when a heat-conducting paste or a similar heat-conducting medium is inserted between the cooling element 4 and the component 3 . On the underside (L side), the cooling element 4 has good thermal contact, e.g. B. also with the help of thermal paste, to a heat sink 8th This can e.g. B. from a heat conductive metal, z. B. copper, exist or z. B. be a so-called heat pipe.

The cooling element 4 designed as a Peltier element is now connected via the connections 6 , 7 to a direct voltage or direct current source such that heat transfer from the component 3 to the cooling body 8 takes place. It can be seen that the choice of the DC voltage applied to the cooling element 4 and / or the direct current flowing through advantageously controls and / or regulates the heat transport and thus the temperature of the component 3 . If required, the direction of the direct current can be changed and / or the cooling element 4 can be turned over. In this case, heat is transported from the heat sink 8 to the component 3 , which is heated thereby. In this way, a regulation of the temperature of the Bauelemen tes 3 , z. B. a quartz crystal possible.

For large-area components 3 and / or for transporting larger amounts of heat, it is expedient to arrange several such cooling elements 4 spatially and electrically in parallel. It can be seen that with such arrangements of cooling elements a very selective cooling of components can be made. For example, only those components and / or locations that heat up particularly strongly can be cooled. These spots are also called "hot spots".

The invention is not limited to the described embodiment, for example, but can be used in many other ways. For example, the substrate 1 z. B. a ceramic substrate of a so-called hybrid circuit. Furthermore, the substrate can also be a housing, e.g. B. a plastic housing of an integrated circuit and / or a high-performance semiconductor device.

It is advantageous that cooling elements of this type can be inserted into the substrate 1 using methods and / or methods customary in circuit and / or semiconductor technology.

When using such cooling elements in printed circuit boards It is advantageously possible to use electrical components elements, e.g. B. integrated circuits, in housings with poss as thin as possible to use pins. Because one of the then usual heat dissipation via these pins no longer needed, so that a further increase in the pack and / or Conductor density is possible. A high Packing density generally means using the SMD technology.

In this, the SMD components have no connection and / or Solder pins that go through the circuit board perform and which a heat transfer to the L-side can effect.

Such substrates equipped with cooling elements, for. B. Head plates, are advantageously mechanically robust, light and have a small volume, so that in particular a inexpensive warehousing is possible.

Claims (8)

1. A method for tempering a component which is attached to an electrically insulating substrate and in which thermal contact with a heat sink is made possible, characterized in that

• - That in the substrate ( 1 ) an opening ( 2 ) is generated, which is in the region of the heat-generating construction element ( 3 ),
• - That in the breakthrough ( 2 ) a thermoelectrically ar working cooling element ( 4 ), which allows heat transfer from the component ( 3 ) to the heat sink when an electrical current flows through the cooling element ( 4 ), is attached and
• - That between the component ( 3 ) and the Kühlele element ( 4 ) a thermal contact is made.

2. The method according to claim 1, characterized in that the cooling element is designed as a semiconductor component. 3. The method according to claim 1 or claim 2, characterized in that the opening ( 2 ) is formed as a through the substrate ( 1 ) passing bore. 4. The method according to any one of the preceding claims, characterized in that the electrical current flowing through the cooling element ( 4 ) is controlled and / or regulated depending on the temperature and / or amount of heat generated in the component ( 3 ). 5. Arrangement for the temperature control of a component which is attached to an electrically insulating substrate and in which a thermal contact with a heat sink is present, characterized in that

• - That in the substrate ( 1 ) is designed as a Peltier element cooling element ( 4 ) and
• - That between the component to be tempered ( 3 ) and the cooling element ( 4 ) a heat-conducting medium is arranged.

6. Arrangement according to claim 5, characterized in that the heat-conducting medium is a thermal paste.   7. Arrangement according to claim 5 or claim 6, characterized in that the substrate ( 1 ) consists of a material suitable for electrical cal printed circuit boards. 8. Arrangement according to one of claims 6 to 6, characterized in that the substrate ( 1 ) is part of a housing to be tempered component.