Printed circuit board comprising an electronic component integrated therein

Abstract

A printed circuit board having two completed printed circuit board elements which consists of a plurality of interconnected plies or layers, wherein at least one printed circuit board element has a cutout or depression containing the component to be integrated on one of the printed circuit board elements or in the cutout of the at least one printed circuit board element, and the printed circuit board elements are connected with the component being accommodated in the cutout, as a result of which it is possible to obtain secure and reliable accommodation of the component in the printed circuit board. Furthermore, a printed circuit board of this type also contains an electronic component integrated therein.

Claims

1. A printed circuit board comprising an electronic component integrated therein, comprising: two completed printed circuit board elements, which more particularly consist of a plurality of interconnected layers or plies, wherein at least one printed circuit board element comprises a cutout or depression; and an electronic component arranged on one of the printed circuit board elements or in the cutout of the at least one printed circuit board element; wherein the printed circuit board elements are connected or connectable after the accommodation of the component in the cutout, wherein evaluation electronics for the component is integrated in the printed circuit board, that partial shielding of the component in its state accommodated in the cutout from the external environment and/or neighboring partial regions of the printed circuit board is provided and that, in the region of contact connections of the component to be integrated, a layer of a hermetically tight, non-conducting material is embedded in a printed circuit board element and a contact connection of the component is realized by blind holes formed through the hermetically sealing layer and filled with a conductive material, a plating or the like.

2. The printed circuit board according to claim 1, wherein the dimensions of the cutout for accommodating the electronic component exceed the dimensions of the component in at least one direction of extension thereof.

3. The printed circuit board according to claim 2, wherein the dimensions of the cutout exceed the dimensions of the component in at last one direction of extension by at least 5%, in particular at least 15%, of the dimension of the component.

4. The printed circuit board according to claim 2, wherein the dimensions of the cutout are selected to exceed the dimensions of the component in any direction of extension of the component.

5. The printed circuit board according to claim 1, wherein the electronic component wherein to be integrated is formed by a sensor, for instance for determining the temperature, moisture, pressure, sound, brightness, acceleration, spatial position, composition of gaseous or liquid media, a high-frequency element or the like.

6. The printed circuit board according to claim 1, wherein at least one passage opening running into the interior of the cutout for accommodating the component is provided.

7. The printed circuit board according to claim 1, wherein shielding is at least partially provided by substantially full-surface, conducting layers of the printed circuit board elements.

8. The printed circuit board according to claim 7, wherein conducting regions wherein of the printed circuit board elements used for shielding are additionally connected by conducting contact connections between the conducting regions of the printed circuit board elements.

9. The printed circuit board according to claim 1, wherein the evaluation electronics for the electronic component is integrated in the printed circuit board element on which the component is supported, or to which the electronic component is contact-connected.

10. The printed circuit board according to claim 1, wherein the connection of the printed circuit board elements in a manner known per se is formed by soldering, eutectic bonding, thermocompression bonding, diffusion soldering, using a conductive adhesive and/or conducting or conductive adhesive films or the like.

Description

SHORT DESCRIPTION OF THE DRAWINGS

(1) In the following, the invention will be explained in more detail by way of exemplary embodiments schematically illustrated in the accompanying drawing.

(2) Therein:

(3) FIG. 1 is a schematic illustration of a printed circuit board comprising an electronic component arranged thereon, according to the prior art;

(4) FIG. 2 is a schematic illustration of a first inventive embodiment of a printed circuit board comprising an electronic component integrated therein and produced by the method according to the invention;

(5) FIG. 3, in an illustration similar to that of FIG. 2, depicts a modified embodiment of a printed circuit board according to the invention, with an evaluation electronics being additionally provided in the immediate vicinity of the integrated electronic component;

(6) FIG. 4, again in an illustration similar to that of FIG. 2, depicts a further modified embodiment of a printed circuit board according to the invention, with the component being arranged in the cutout provided in a printed circuit board element; and

(7) FIG. 5 is a schematic illustration of a further modified embodiment of a printed circuit board according to the invention, wherein a hermetic seal is also provided in the region of contacts of the electronic component to be integrated.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

(8) From the configuration according to the prior art as is schematically indicated in FIG. 1, it is apparent that an electronic component 101 is arranged on a printed circuit board element 100, which may, for instance, consist of a plurality of different layers or plies, which are not shown in detail, wherein only two contacts 102 are schematically indicated. The electronic component 101 is, for instance, formed by a microphone, wherein a metallic cage 103 is indicated to achieve appropriate shielding of the electronic component arranged on the printed circuit board element 100, said cage being connected, via connections 104, to conducting elements not illustrated in detail. Further contact connections of the printed circuit board, or structured conducting elements of the same, are schematically indicated by 105 and 106.

(9) According to the prior art, an electronic component 101 to be additionally protected or shielded is thus arranged on a surface of a printed circuit board, wherein, in the present case, which uses the electronic component 101 as a microphone, a hole or passage opening 107 for the sound to be recorded by the microphone 101 is indicated. It is immediately apparent that this known embodiment not only involves considerable additional expenditures for the subsequent production of the shield 103, which is, for instance, formed by a metal cage, but also can by no means ensure an adequately protected or safe accommodation of the electronic component 101.

(10) In the embodiment according to the invention, which is represented in FIG. 2, an, in particular multilayer, printed circuit board element 1 is provided similarly as in the prior art according to FIG. 1, to which an electronic component 3 is again fixed via schematically indicated contacts 2.

(11) Via connections 5, which will be discussed in more detail below, a second printed circuit board elements 4 is connected to the previously completed printed circuit board element 1, wherein a plurality of different layers or plies 6, 7, 8 and 9 are to be seen or indicated in the second printed circuit board element 4. The likewise previously completed printed circuit board element 4 is, moreover, formed with a cutout or recess or depression 10, whose dimension in the embodiment illustrated in FIG. 2 exceeds the dimensions of the electronic component 3 in any direction of extension, wherein the distances, or the free space, between the component 3 and the boundary walls of the recess or depression 10 are shown not true to scale but extremely large, in particular to elucidate the illustration.

(12) When again using the component 3 as a microphone, a passage opening or sound hole 11 is also provided in the printed circuit board 1 similarly as in the embodiment according to FIG. 1.

(13) In order to achieve appropriate shielding against electromagnetic radiation of the component or microphone 3, a metallic cage substantially completely surrounding the component 3 is formed by a substantially full-surface layer 12 of conductive material directly constituting a separation layer or ply of the previously completed multilayer printed circuit board element 4, and by contact connections 13 in the region of the contact connections or connections 5. Such contact connections 13 are formed by passage openings, which are known in the production of printed circuit boards and are, for instance, likewise filled with conductive material or at least plated therewith. When providing a connection 5 likewise of conducting material, e.g. a solder connection 5, reliable shielding integrated in the printed circuit board elements 1 and 4 will be immediately achieved upon connection of the two printed circuit board elements 1 and 4 after the arrangement of the electronic component or sensor 3.

(14) When embedding a microphone 3 as a component to be integrated, achievement of sound qualities of the component will, for instance, also be possible by renouncing the metallic shield to be separately arranged as in the prior art according to FIG. 1, and embedding the component 3 into the prefabricated printed circuit board elements 1 and 4.

(15) Additional structures or contacts 14 and 15 as are provided in the embodiment according to the prior illustrated in FIG. 1 are also shown in the printed circuit board element 1.

(16) In the configuration according to FIG. 3, a previously completed printed circuit board element 21 is again provided as in the embodiment according to FIG. 2, on which an electronic component 23 is arranged so as to be supported by contacts 22.

(17) To the printed circuit board element 1 is connected a second previously completed printed circuit board element 24, which is again formed by a multilayer printed circuit board element, such multiple layers or plies known per se having been omitted from FIG. 3 for reasons of simplicity.

(18) Similarly as in the preceding embodiment, a connection 25 is again provided between the printed circuit board elements 21 and 24, wherein the electronic component 23 is arranged in a recess or depression 26 again provided in the printed circuit board element 24, whose dimensions, which are enlarged relative to the dimensions of the component 23, are again illustrated in an exaggerated manner for the sake of clarity.

(19) For an additional shielding to be again provided when, for instance, used as a microphone, a substantially full-surface layer of a conductive metallic material in the printed circuit board element 24 is denoted by 27, wherein passage openings 28 are again indicated to complete the shield similarly as in the preceding embodiment, which passage openings again provide shielding surrounding the electronic component 23 during or after filling or at least plating with a conducting material, and when providing a connection 25 of conducting material.

(20) A passage opening to the free space 29 defined by the recess 26, in which the component or sensor 23 is arranged or received or integrated, is denoted by 30.

(21) In the embodiment illustrated in FIG. 3, it is additionally provided that evaluation electronics 31 for the component 23 is provided in the immediate spatial vicinity and, in particular, integrated in the printed circuit board element 21 such that, in view of the miniaturization of such a modularly structured sensor directly integrated or integratable in a printed circuit board, the recording and/or evaluation of the measuring data or measured values determined by the sensor 23 will be enabled.

(22) In the further modified embodiment represented in FIG. 4, a printed circuit board element 41 again consisting of several layers is provided with a recess or depression 42, wherein an electronic component 43 is directly fixed in said recess 42 of the printed circuit board element 41 via contacts 44. Similarly as in the preceding embodiment, evaluation electronics 45 is again integrated in the printed circuit board element 41 in the immediate vicinity of the component 43, a contact connection between the component 43 and the evaluation electronics being schematically indicated by 46. Also the embodiment according to FIG. 4 comprises a passage opening 47 for connecting the sensor or component 43 to the external environment.

(23) Similarly as in the preceding embodiments, a further printed circuit board element 48 is connected or coupled to the printed circuit board element 41 via connections 49, wherein, in order to provide shielding, passage openings 51 are again provided with the appropriate metallic plating or the like beside a layer or ply 50 of conducting material, similarly as in the preceding embodiments.

(24) From the schematic illustration according to FIG. 5, it is apparent that, as known per se in the manufacture of printed circuit boards, a great plurality of similar elements are usually produced in a common carrier or an accordingly large format, wherein, after the completion of the individual printed circuit boards, the latter are subdivided into individual modules or elements.

(25) In the embodiment according to FIG. 5, it is, moreover, indicated that, unlike in the preceding embodiments according to FIGS. 2 to 4, a substantially hermetic seal of the electronic component to be accommodated is to be provided.

(26) To this end, a layer or ply 62 of hermetically sealing material such as glass, ceramic or the like is provided or integrated in an already completed printed circuit board element 61, which is again comprised of a plurality of layers or plies, which are not illustrated in detail for the sake of simplicity. Similarly as in the preceding embodiments, an electronic component or sensor 63 is arranged in the printed circuit board element 61 via schematic contacts 64, said electronic component 63 being arranged or integrated in a recess 65 of a further printed circuit board element 66. Connection between the printed circuit board elements 61 and 66 is effected via schematically indicated connections 67.

(27) In contrast to the preceding embodiments, the embodiment illustrated in FIG. 5 requires hermetic sealing of the component or sensor 63 against the external environment, wherein, in addition to the seal comprised of the hermetically sealing material 62, a plating 68 is provided in the printed circuit board element 66, which plating also extends into the respective passage holes or openings 69 in the region of the connections 67. By providing a continuous plating or full-surface material layer of a metallic material, adequate tightness will be provided, enabling a full-surface sheathing or shielding of the component 63 by the seal comprised of the material 62.

(28) In the region of the hermetically sealing material 62, feedthroughs 70 are provided by suitable bores or blind holes penetrating the hermetically tight material 62. In this manner, adequate hermetic sealing of the component 63 can also be provided in the region of the contacts to be mutually separated.

(29) The printed circuit board element 61, in addition to the feedthroughs 70, comprises slots or bores or passages 73 penetrating the material 62, which, similarly as the holes 69, are, for instance, galvanically plated to complete hermetic shielding in addition to electromagnetic shielding.

(30) In FIG. 5, a separation line 72 for separating adjacent modules is, moreover, provided after the completion of the individual modules, only the printed circuit board elements 61 and 66, respectively, being schematically indicated for the adjacent module.

(31) As opposed to the shown illustrations, it is known that such electronic components comprise an extremely large plurality of contacts or contact sites, wherein substantially only two contacts 2, 22, 44 and 64 are respectively indicated in the illustrations for the sake of simplicity.

(32) It is, moreover, not necessarily required, in particular as a function of the purpose of use or application of the electronic component 3, 23, 43 or 63, as is shown in the illustrations particularly for reasons of elucidation, that the free spaces formed by the respective recesses or depressions 10, 26, 42 or 65 exceed by the extent shown the dimensions of the electronic component 3, 23, 43 or 63 to be respectively accommodated.

(33) It may also be provided that the dimensions of the respective recess or depression 10, 26, 42 or 65 is substantially adapted to the dimensions of the component 3, 23, 43 or 63 to be accommodated or integrated such that the component will be received in the respective recess or depression in a substantially precisely fitting manner. What is essential is that by respectively providing completed printed circuit board elements 1, 4, 21, 24, 41, 48 or 61 and 66, the dimensions of the free space defined by the recesses 10, 26, 42 or 65 will be maintained unchanged.

(34) To provide a connection 5, 25, 49, 67 of the printed circuit board elements 1, 4, 21, 24, 41, 48 or 61 and 66 to be connected, it will also be possible, besides a solder connection as indicated above, to realize such a connection by eutectic bonding, thermocompression bonding, diffusion soldering, or a connection using a conductive adhesive and/or conducting or conductive adhesive films, if shielding of conducting materials is required. Unless such continuous shielding of the component of conducting material, for instance by forming a Faraday cage, is required, adhesive connections of non-conductive materials may, for instance, also be provided.

(35) Besides the configuration, for instance, as a microphone of the electronic component 3, 23 or 43 to be integrated or accommodated, to which end a passage opening 11, 30 or 47 in the form of a sound hole is respectively provided, such components can also be used to determine other physical values such as, e.g., the temperature, moisture, pressure, brightness or, in general, the composition of gaseous or liquid media. Alternatively, the electronic component may be comprised of a high-frequency element.

(36) In an embodiment according to FIG. 5, in which a substantially hermetic seal is provided, an acceleration sensor or position sensor or any other type of sensor for which shielding against environmental influences or influences from the external environment has to be safely provided may, for instance, be integrated in the free space provided by the cutout or recess.

(37) In addition to shielding the component or sensor 3, 23, 43 or 63 from environmental influences, shielding may also be used to protect further elements or components of a printed circuit board region not illustrated in detail in the drawings, if, for instance, the determination of the composition of aggressive media in the region of the electronic component 63 is to be performed.

(38) Overall, embedding of the components or sensors 3, 23, 43 or 63 is effected using method steps that are generally known in the manufacture of printed circuit boards.