KR20070028309A - Electronic component on a supporting element - Google Patents

Abstract

The invention concerns a device comprising an electronic component (110) and a supporting element, particularly a printed circuit board, and to a method for producing a device of this type. The invention provides that the electronic component (110) and the supporting element have an electric contacting effected via at least one first material. In addition, at least one first region comprised of a second material (200) is provided between the electronic component and the supporting element. The second region functions as a spacer. The invention is characterized in that the first and second material (200) have a comparable mechanical behavior. ® KIPO & WIPO 2007

Description

ELECTRONIC COMPONENT ON A SUPPORTING ELEMENT}

The present invention relates to a device according to the preamble of the independent claim and a method for manufacturing the device.

Electronic components (SMDs) are typically soldered onto a support material, such as on a printed circuit board, using a lead cream in a thermal process. Over the service life of the components manufactured as described above, it can be observed that breakage occurs in the solder joint based on temperature changes. At this time, based on the thermal load, inside the solder material or the lead cream, fine cracks may occur that may cause the solder joint to break. Such solder joint failures continue to limit the service life of such electronic components.

The present invention relates to an electronic component and a support element, and above all, a device having a printed circuit board; and a method for manufacturing such a device. According to the proposal of the invention, the electronic component and the support element comprise an electrical contact, which electrical contact is formed by at least one first material. In addition, a first region of a second material is provided between the electronic component and the support element, and above all, the second region serves as a spacer. The key point of the present invention is that the first and second materials have a comparable mechanical behavior.

By using the first region between the electronic component and the support element, an extension of the service life of the device of the present application, more preferably consisting of the two members described above, is achieved. In this regard, it is desirable to use materials that are comparable in electrical properties and the first region at least in their mechanical properties in manufacturing. This is because it enables easy simultaneous processing during manufacturing. As a result, it is possible to generate the first region without increasing the processing time.

According to an improvement of the invention, the first material and / or the second material have a deformation dependent on the temperature. In addition, optionally, at least one of the two materials may include a solder joint. By using solder for both materials, simple processing in manufacturing can be achieved. In addition, the use of solder incurs only very minimal additional costs.

According to a particularly preferred embodiment of the invention, the electronic component has a mechanical contact to the support element at least partly irrespective of the electrical contact. In this case, such mechanical contact is more preferably made over the first area, and above all, the first area has at least one support point for the electronic component. For example, through such a support point, which can function as a spacer, the warpage of the electronic component is suppressed. However, alternatively, it is also conceivable that, through the support point, another electrical contact is made irrespective of the electrical contact between the electronic component and the support element. However, very generally the load on the electrical contact can be more preferably relaxed through the first region or the support point.

According to a particular embodiment of the invention, a sealing ring is mounted on the electronic component, which seal connects the electronic component with, for example, a casing. At this time, the sealing ring as described above may be in close contact with the electronic component using a pressure force. Particularly preferably in this regard the shape of the first region depends on the pressure ratio resulting from pressing the sealing ring, because in this way the transmission of forces on the electrical contact can be suppressed or reduced. By thus reducing the force transmitted on the solder joint that creates the electrical contact, the risk or sensitivity to solder joint failure is reduced.

In this regard, the shape of the first region according to the pressure ratio may be various. Therefore, it is also conceivable to adapt the number of first regions between the electronic component and the support element to match the pressure ratio. However, depending on the alternative method, at least one provided under the electronic component or the geometrical shape of each individual first region, in order to enable the best possible compensation of the pressure forces and thus the maximum global load mitigation of the electrical contacts, is possible. The location of one area may be changed. By suitably selecting the number and size of the first regions, the aging process of the electrical contact, more particularly the solder joint, can be significantly suppressed or delayed. In this regard, the pressure ratio can be determined in particular taking into account the magnitude of the pressure force, the starting point of the pressure force provided on the electronic component, and the direction of the pressure force.

Particularly preferably, the first region is designed as a soldering support point, as a supporting ball, and / or as a soldering support protrusion, in which a plurality of first regions can be arranged under the electronic component in clear fact. .

According to one embodiment of the invention, the electronic component comprises a sensor element. This sensor element supplies the critical measurement variable for the positional displacement. For this reason, through the first region, the positional displacement of the electronic component based on external pressure application can be reduced to a minimum value. In general, sensor elements for detecting pressure variables, air mass variables, oil state variables and / or temperature variables may be provided.

In order to manufacture the device according to the invention, a solder joint characterizing the first region can be glued onto a support material together with the solder joint for electrical contact, among other things, to assemble the electronic component.

Further advantages of the invention are described in more detail below in the description of the embodiments and from the independent patent claims.

Fig. 1A is a schematic diagram showing the configuration of a device composed of an electronic component and a support element.

1 (b) and 1 (c) are detailed views of parts showing solder breakage in the electrical contact portion.

2 is a schematic diagram illustrating mechanical load mitigation of electrical contacts in accordance with the present invention.

Figure 3 is a schematic diagram illustrating an embodiment in which support points are arranged in a pressure sensor in accordance with the present invention.

4 is a schematic diagram illustrating a possible implementation of a support element that can be implemented prior to assembly of an electronic component in accordance with an embodiment.

As is known from the prior art, a device consisting of electronic component 110 (SMD; surface mount element) and support element 100 is shown in FIG. 1A. In this regard, the electronic component 110 includes electrically conductive terminals 120, which form electrical contacts with the support element 100 using a solder joint 130. Preferably the terminals 120 are designed in such a way as to enable positioning on the support element 100. This is typically accomplished through terminals 120 having a longer length than the body of the electronic component 110. By doing so, on one side it is possible to position the electronic component 110 on the support element 100 via a terminal foot, and on the other side, the bottom of the electronic component 110 has the support element 100. The point where it adheres to) is suppressed. As a result, a (air) gap 190 is provided between the electronic component 110 and the support element 100.

If the solder joints 130 are exposed to frequent temperature changes over time, coarse particles or fine cracks may form inside the solder. Such cracks can, in extreme cases, lead to breakage of the solder joint. Such solder joint failures often occur at the end of the life of the device with such solder joints. If the electronic component 110 or solder joint is additionally exposed to a mechanical load, the solder joint 130 is destroyed at an earlier time and thus undergoes an earlier aging process. Corresponding mechanical loads may be generated, for example, by pressure forces 150 acting on the electronic component 110 continuously or sporadically.

1 (b) and (c) show a state in which a solder joint break occurred based on an external force action 150 on the electronic component 110 at a portion corresponding to the region 140. Since the component 110 may be bent by the pressure force 150 due to the gap 190, the mechanical load of the solder joint 130 shown in the divided form of the force in FIG. 1B is generated. . In addition to the vertical force component 160, from the resulting force 180 acting on the terminal 120 and the solder joint 130, the terminal 120 is directed outward, ie away from the electronic component. A horizontal force component 170 is created that is in close contact with the. As described above, the particles become coarse in the solder material of the solder joint 130, so that a crack is formed, and finally, the solder joint 130 is broken into one or more fragments as shown in FIG. 1C. do. Simultaneously with this breakdown of the solder joint 130, the electrical contact between the electronic component 110 and the support element 100 is also destroyed. For this reason, according to the soldering rate of solder engineering for SMD components, no pressure or any force should be applied on the solder joint.

Therefore, in order to suppress earlier solder joint failure, one or more support points 200 are glued onto the support element under the electronic component 110 in accordance with the present invention. Using the support points 200 as described above, the body of the electronic component 110 can be affected by the external force 150 only very limitedly. As a result, the force 180 that occurs and acts on the terminal 120 or the solder joint 130 is reduced. Thereby the horizontal force component 170 is likewise reduced or completely suppressed through the proper selection of the position of the support points 200.

In general, the support points may vary depending on the pressure ratio or load ratio acting on the electronic component 110. In this regard, the number, position and individual geometry of the individual supports can also be changed. More preferably, a plurality of support points 200 are provided between the electronic component 110 and the support element 100. Accordingly, the force 150 may be divided into a plurality of partial forces 155.

3 shows a particular embodiment. According to this embodiment, the electronic component 110 comprises a special micromechanical sensor element for pressure detection. However, it is also conceivable that the electronic component 110 is suitable for detecting air mass variables, oil state variables and / or temperature variables. Since the sensor element for pressure detection must be in contact with the surrounding medium, an opening 320 can be provided in the casing 310, through which the medium is attached to the sensor element inside the electronic component 110. Contact with. At this time, more preferably, a sealing ring 300 is mounted on the electronic component 110. This sealing ring 300 is pressed against the electronic component 110 by a constant force 330 by the casing 310. To compensate for such force 330, support points 200 may be adhered to the bottom of the electronic component 110 in such a way that the resulting horizontal force component of the force is avoided.

According to a particular embodiment of the invention, the support points are realized as solder joints, solder protrusions or as solder balls. Accordingly, the support points 200 may be manufactured at the same time as the solder joints 130 in the manufacturing process. Therefore, an additional, in some cases, increase in process time caused by complex process steps is not necessary. In addition, when using solder as the material for the support points, the additional cost, which is determined by the excessive excess consumption of the solder, is very minimal. Since the support points, or the support balls and the solder joints are made of the same material, the support points, the support balls and the solder joints likewise have the same mechanical properties, whereby an undesirable deformation of the electronic component, for example occurring on the support element, Restrained during manufacture or operation of the device. In addition, the supports extend the service life of solder joints by several times. This is because effects that may speed up the aging process of solder joints are blocked or delayed.

According to yet another embodiment, various contact surfaces are provided before assembling the electronic component on the support element. These contact surfaces are subsequently soldered to the terminals of the electronic component. Such support element 400 is shown in FIG. 4 in accordance with an embodiment. In this regard, various contact surfaces 410, 420, 430 can be identified, with which the electronic component can be aligned on the surface of the support element. To enable an efficient manufacturing process, the support points 440 are glued simultaneously with the contact surfaces before the electronic component is mounted on the support element. In this regard, FIG. 4 shows only one possible implementation of the positioning of the supports. Likewise, a triangular arrangement, pentagonal arrangement, or other symmetrical or asymmetrical arrangement of support points can be considered.

However, according to a particular embodiment of the invention, the support points may be glued directly to the back of the electronic component, ie to the bottom, before being assembled on the support element.

In addition to using solder as the support material as described above, it is conceivable to prepare support points with epoxide adhesive. In addition, the casing of the electronic component may be configured using a standoff. However, the use of standoffs can lead to new component types that can only be realized by new production lines during packaging manufacturing. In addition, when using the standoff, it is also necessary to take into account that the appropriate layout should be selected in order to prevent the standoff from being crushed by the temperature change.

According to yet another embodiment, the electronic component of FIG. 2 may not be initially supported on the supports. Therefore, it may be proposed, for example, that the electronic component must first overcome a small gap until mechanical contact with the support point is made when a force is applied. It may also be proposed that the gap should be overcome at at least one support point, whereas mechanical contact is created at the at least one support point without applying force.

Claims (15)

A device having an electronic component 110 and a support element 100, in particular a printed circuit board, The electronic component 110 and the support element 100 have an electrical contact 130 using at least one first material, In an apparatus provided with at least one first region 200 made of a second material between the electronic component 110 and the support element 100, And the second material has a mechanical behavior corresponding to the first material as broadly as possible. The method of claim 1, wherein the first material and / or the second material Deformations and / or temperature dependent And a solder joint. The electronic component 110 of claim 1, wherein the electronic component 110 forms a mechanical contact to the support element 100 at least partially over the first region 200 independently of the electrical contact 130. The region (200) comprises at least one support point (200) for the electronic component (110). The method of claim 1, wherein the first region 200 mechanically relieves the load of the electrical contact, and the first region 200 includes at least one support point 200 or a support ball. Device. A sealing ring 300 is mounted on the electronic component 110, the sealing ring 300 being fixed on the electronic component 110 under pressure force 330. The first region (200) is formed according to the pressure ratio. The method of claim 5, wherein according to the pressure ratio, Number and / or number of the first region The geometrical shape of the first region and / or The position of the first area is preset between the electronic component 110 and the support element 100, As the pressure ratio, the pressure force, the starting point of the pressure force and the direction of the pressure force are considered. The device of claim 1, wherein the electronic component comprises a sensor element, the sensor element detecting a pressure variable, an air mass variable, an oil state variable and / or a temperature variable. 2. The device of claim 1, wherein a plurality of solder joints are disposed as solder support protrusions under the electronic component. 10. A method for manufacturing an apparatus comprising an electronic component 110 and a support element 100, in particular a printed circuit board, more particularly an apparatus according to any one of the preceding claims, An electrical contact 130 is created between at least one first material between the electronic component 110 and the support element 100, In the method, at least one first region 200 made of a second material is created between the electronic component 110 and the support element 100. And the second material has a mechanical behavior corresponding to the first material as broadly as possible. The method of claim 9, wherein the first material and / or the second material, Deformations and / or temperature dependent And a solder joint. The method of claim 9, wherein the electronic component 110 forms a mechanical contact to the support element 100 over at least a portion of the first region 200 independently of the electrical contact 130. The first region (200) comprises at least one support point (200) for the electronic component (110). The method of claim 9, wherein the first region 200 mechanically relaxes the load of the electrical contact 130, and the first region 200 includes at least one support point 200 or a support ball. Characterized in that the method. The sealing ring 300 is mounted on the electronic component 110, wherein the sealing ring 300 is fixed on the electronic component 110 under a pressure force 330. Wherein the shape of the region 200 can be preset according to the pressure ratio. The method of claim 13, wherein, depending on the pressure ratio, Number and / or number of the first region The geometrical shape of the first region and / or The position of the first area can be preset between the electronic component 110 and the support element 100, Above all, as the pressure ratio, the pressure force, the starting point of the pressure force and the direction of the pressure force are considered. The method of claim 10, wherein a solder joint in the first region (200) is glued onto the support material (100) prior to assembly of the electronic component (110).

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