CIRCUIT BOARD STRUCTURE HAVING ELECTRONIC COMPONENTS EMBEDDED THEREIN AND METHOD OF FABRICATING THE SAME

A circuit board structure having electronic components embedded therein and a method of fabricating the same are provided. The circuit board structure includes a substrate having a first circuit layer formed on at least one surface thereof, electronic components electrically connected to the first circuit through a metallic connector, a first dielectric layer formed on the first circuit layer of the substrate and having a plurality of dielectric layer cavities for the first circuit layer to be exposed therefrom and the electronic components to be received therein, a plurality of vias, a second dielectric layer formed on the first dielectric layer and the electronic components and having a plurality of dielectric layer vias for the electronic components to be exposed therefrom and the vias to be formed therein, and a second circuit layer formed on the second dielectric layer and electrically connected to the electronic components through the vias.

DETAILED DESCRIPTION OF THE INVENTION

Likewise, the drawings showing embodiments of the structure are semi-diagrammatic and not to scale and, particularly, some of the dimensions are for the clarity of presentation and are shown greatly exaggerated in the drawings. Similarly, although the views in the drawings for ease of description generally show similar orientations, this depiction in the drawings is arbitrary for the most part. Generally, the invention can be operated in any orientation.

FIRST EMBODIMENT

FIGS. 2A to 2Gare cross-sectional views illustrating a circuit board structure having electronic components embedded therein of a first embodiment according to the present invention, wherein FIG.2G′ is another embodiment ofFIG. 2G.

As shown inFIG. 2A, a substrate2is composed of a core carrier board20; a plurality of conductive through holes201penetrating two surfaces of the core carrier board20; and a first circuit layer21formed on two opposing surfaces of the core carrier board20and electrically connected to the conductive through holes201.

As shown inFIG. 2B, a first dielectric layer22is formed on two opposing surfaces of the substrate2. The first dielectric layer22is made of a prepreg material.

As shown inFIG. 2C, a portion of the first dielectric layer22is removed by a laser burning method to form a plurality of dielectric layer cavities220for the first circuit layer21to be exposed therefrom.

As shown inFIG. 2D, a metallic connector23is formed on the exposed portion of the first circuit layer21by a screen printing method. The metallic connector23is made of silver paste, copper paste or conductive metal adhesive.

As shown inFIG. 2E, a plurality of electronic components24are disposed in the dielectric layer cavities220, and electrically connected in series or parallel to the first circuit layer21through the metallic connector23. A first portion of the electronic components24are erectly disposed in the dielectric layer cavities220, while a second portion of the electronic components24are lain in the dielectric layer cavities220. And each of the dielectric layer cavities220has a length and a width corresponding to a corresponding one of the electronic components24received therein. In an embodiment, an electronic component24or a plurality of electronic components24can be used. In an embodiment, the electronic components24are capacitors such as multi-layer ceramic capacitor (MLCC).

As shown inFIG. 2F, a second dielectric layer25and a metallic layer26are formed on the first dielectric layer22and the electronic components24sequentially.

As shown inFIG. 2G, a plurality of vias251are formed in the second dielectric layer25, and the metallic layer26is patterned to form a second circuit layer261. The second circuit layer261is electrically connected to the electronic components24through the vias251in the second dielectric layer25. A first portion of the vias251corresponding to the first portion of erectly disposed electronic components24is less in depth than a second portion of the vias251corresponding to the second portion of the electronic components24. A circuit board structure having electronic components embedded therein is thus obtained.

Alternatively, as shown in FIG.2G′, only one side of the substrate2is formed with the metallic connector23and provided with the electronic components24, which can be understood by persons having ordinary skill in the art, further description thereof hereby omitted.

SECOND EMBODIMENT

FIGS. 3A to 3Gare cross-sectional views illustrating a method of fabricating a circuit board structure having electronic components embedded therein of a second embodiment according to the present invention, wherein FIG.3G′ is another embodiment ofFIG. 3G.

As shown inFIG. 3A, a substrate3is composed of a core carrier board30having cavities300penetrating two opposing surfaces thereof; embedded electronic components31disposed in the cavities300; a core dielectric layer32formed on the two surfaces of the core carrier board30and the embedded electronic components31; and a first circuit layer33formed on the core dielectric layer32and electrically connected to the embedded electronic components31. In an embodiment, the embedded electronic components31are capacitors such as multi-layer ceramic capacitors (MLCC).

As shown inFIG. 3B, a first dielectric layer34is formed on two opposing surfaces of the substrate3. The first dielectric layer34is made of a prepreg material.

As shown inFIG. 3C, a portion of the first dielectric layer34is removed by the laser burning method to form a plurality of dielectric layer cavities340for the first circuit layer33to be exposed therefrom.

As shown inFIG. 3D, a metallic connector35is formed on the exposed portion of the first circuit layer33by a screen printing method. In an embodiment, the metallic connector35is made of silver paste, copper paste or conductive metal adhesive.

As shown inFIG. 3E, a plurality of electronic components36are disposed in the dielectric layer cavities340, the electronic components36are electrically connected in series or parallel to the first circuit layer33through the metallic connector35, a first portion of the electronic components36are erectly disposed in the dielectric layer cavities340, a second portion of the electronic components36are lain in the dielectric layer cavities340, and each of the dielectric layer cavities340has a length and a width corresponding to a corresponding one of electronic components36received therein. In an embodiment, only an electronic component24or a plurality of the electronic components36can be used. In an embodiment, the electronic components36are capacitors such as multi-layer ceramic capacitor (MLCC).

As shown inFIG. 3F, a second dielectric layer37and a metallic layer38are formed on the first dielectric layer34and the electronic components36sequentially.

As shown inFIG. 3G, a plurality of vias371are formed in the second dielectric layer37, the metallic layer38is patterned to form a second circuit layer381, and the second circuit layer381is electrically connected to the electronic components36through the vias371in the second dielectric layer37. A circuit board structure having electronic components embedded therein is thus obtained.

Alternatively, as shown in FIG.3G′, only one side of the substrate3is formed with the metallic connector35and provided with the electronic components36, which can be understood by persons having ordinary skill in the art, further description thereof hereby omitted.

The present invention further provides a circuit board structure having electronic components embedded therein, having the substrate2,3having a first circuit layer21,33formed on at least one surface thereof; a first dielectric layer22,34formed on the surface of the substrate2,3and having a plurality of dielectric layer cavities220,340for the first circuit layer21,33to be exposed therefrom; a plurality of electronic components24,36disposed in the dielectric layer cavities220,340and electrically connected to the first circuit layer21,33through the metallic connector23,35, a first portion of the electronic components24,36being erectly disposed in the dielectric layer cavities220,340, and a second portion of the electronic components24,36are lain in the dielectric layer cavities220,340; a second dielectric layer25,37formed on the first dielectric layer22,34and the electronic components24,36and having a plurality of dielectric layer vias for the electronic components24,36to be exposed therefrom, a first portion of dielectric layer vias corresponding to the first portion of the electronic components24,36being less in depth than a second portion of the dielectric layer vias corresponding to the second portion of electronic components24,36; a plurality of vias251,371formed in the dielectric layer vias, a first portion of vias251,371corresponding to the first portion of the electronic components24,36being less in depth than a second portion of the vias251,371corresponding to the second portion of the electronic components24,36; and a second circuit layer261,381formed on the second dielectric layer25,37and electrically connected to the electronic components24,36through the vias251,371.

According to the circuit board structure having the electronic components embedded therein, the substrate2is composed of a core carrier board20; a plurality of conductive through holes201penetrating two opposing surfaces of the core carrier board20; and the first circuit layer21formed on at least one surface of the core carrier board20and electrically connected to the conductive through holes201. Alternatively, the substrate3may include: a core carrier board30having cavities300penetrating two opposing surfaces thereof; embedded electronic components31disposed in the cavities300; a core dielectric layer32formed on the two surfaces of the core carrier board30and the embedded electronic components31; and the first circuit layer33formed on the core dielectric layer32and electrically connected to the embedded electronic components31.

According to the circuit board structure having the electronic components embedded therein, the electronic components24,36is electrically connected in series or parallel to the first circuit layer21,33, the electronic components24,36are resistors, capacitors, inductors or chips, the metallic connector23,35are silver paste, copper paste or conductive metal adhesive, and each of the dielectric layer cavities220,340has a length and a width corresponding to one of electronic components24,36received therein.

Compared with the prior art, the present invention has a plurality of electronic components vertically or horizontally embedded in a circuit board, and the electronic components can be thus stacked on one another. Therefore, the present invention can achieve connecting the electronic components in series and in parallel. Therefore, the design flexibility of the circuit board is enhanced, and the high complexity, powerful functionalities, and custom-made requirements for product design are met.

The foregoing descriptions of the detailed embodiments are only illustrated to disclose the features and functions of the present invention and not restrictive of the scope of the present invention. It should be understood to those in the art that all modifications and variations according to the spirit and principle in the disclosure of the present invention should fall within the scope of the appended claims.