1. Field
The present invention relates to a substrate for a capacitor-embedded printed circuit board, a capacitor-embedded printed circuit board, and a manufacturing method thereof.
2. Description of the Related Art
For today's electronic appliances, including portable devices, an increasing number of consumers have been placing a wider variety of demands. In particular, the consumers are pressuring the designers and manufacturers for new devices that are more multifunctional, compact, light-weight, high-speed, inexpensive, mobile, internet-accessible wirelessly and fashionable. As a result of this intense competition, new models hit the market more quickly, and the shortened life cycle of new models adds more pressure to the designers and manufacturers.
Accordingly, the number of passive components is increased with the boosted number of ICs due to the diversified functions in a product, making a portable apparatus bulkier. An electronic appliance typically has a plurality of active components and passive components mounted on a printed circuit board. Particularly, a large number of passive components are mounted in the form of a discrete chip capacitor on the surface of a printed circuit board in order to allow signals to be smoothly transferred.
Many companies are developing an embedded printed circuit board to increase the density of an electronic system. The passive parts embedded in the board include L. R and C types. However, the separate-chip-type passive parts have not been successful in making a product compact, light and thin, space-efficient and cost-effective.
While there are various ways to realize an embedded capacitor, there has been much attention to realizing the embedded capacitor by use of an RCC-type material (Resin Coated Copper), for which the thickness can be easily adjusted. However, since the RCC-type material has a poor laminating property, it requires an additional process of smoothing the surface, on which the RCC-type material is laminated.
This type of structural problem of the RCC-type material causes a circuit pattern thickness of the laminated surface to be largely varied or a dielectric substance of the RCC-type material to be largely varied with respect to the thickness of resin, in spite of the additional process of smoothing the laminated surface. Sometimes, this results in defect such as delamination of the laminated surface.
The present invention provides a capacitor, a substrate for a capacitor-embedded printed circuit board, a capacitor-embedded printed circuit board, and a manufacturing method thereof that can simplify the manufacturing process and reduce the variation of capacitance (C) to improve the product reliability.
An aspect of the invention provides a substrate for a capacitor-embedded printed circuit board including a dielectric layer; and a first adhesive resin layer, configured to be stacked on a surface of the dielectric layer. Here, roughness can be formed on the first adhesive resin layer.
The substrate can further include a second adhesive resin layer, configured to be stacked on another surface of the dielectric layer. Here, roughness can be formed on the second adhesive resin layer. At this time, the substrate can further include a first metal layer, configured to be stacked on the first adhesive resin layer. The substrate can further include a second metal layer, configured to be stacked on the second adhesive resin layer.
Another aspect of the invention provides a capacitor-embedded printed circuit board including a core board; an insulation resin layer, configured to be stacked on the core board; a first electrode and a first circuit pattern, configured to be buried in the insulation resin layer; a dielectric layer, configured to be stacked on a surface of the insulation resin layer; a first adhesive resin layer, configured to be stacked on the dielectric layer; and a second electrode and a second circuit pattern, configured to be formed on a surface of the first adhesive resin layer to correspond with the first electrode.
The first adhesive resin layer can be desmeared. The printed circuit board can further include a second adhesive resin layer, configured to be interposed between the insulation resin layer and the dielectric layer. The second adhesive resin can be desmeared.
Also, the printed circuit board can further include an insulation board, configured to be stacked on the first adhesive resin layer to cover the second electrode; a third circuit pattern, configured to be formed on a surface of the insulation board; and a via, configured to pass through the insulation board.
Another aspect of the invention provides a method of manufacturing a capacitor-embedded printed circuit board including providing a substrate on which a first metal layer, a dielectric layer and an adhesive resin layer are stacked on the order thereof; etching a part of the first metal layer to form a first electrode and a first circuit pattern; compressing a surface of the substrate, on which the first electrode is formed, onto a core board by interposing an insulation resin layer; forming a second electrode and a second circuit pattern on the adhesive resin layer; stacking an insulation board on the substrate such that the second electrode and the second circuit pattern are covered; and forming a third circuit pattern on the insulation board
A second metal layer can be stacked on the adhesive resin layer, and in the forming the second electrode and the second circuit pattern, a part of the second metal layer can be etched.
Also, the method can further include desmearing the adhesive resin layer, prior to the stacking the insulation board. At this time, the forming the second electrode and the second circuit pattern can include forming a seed layer on the desmeared adhesive resin layer; forming a plating resist on the seed layer; forming a plating layer corresponding to the second electrode and the second circuit pattern through electroplating; removing the plating resist; and performing flash-etching such that a part of the seed layer is removed.
However, the forming the second electrode and the second circuit pattern can be performed before the compressing a surface of the substrate onto a core board.
Also, two substrates can be provided, and the compressing a surface of the substrate onto a core board can be performed on both surfaces of the core board.
Another aspect of the invention provides a method of manufacturing a capacitor-embedded printed circuit board including providing a substrate on which a first metal layer, a first adhesive resin layer, a dielectric layer and a second adhesive resin layer are stacked on the order thereof; etching a part of the first metal layer to form a first electrode and a first circuit pattern; desmearing the first adhesive resin layer; compressing a surface of the substrate, on which the first electrode is formed, onto a core board by interposing an insulation resin layer; forming a second electrode and a second circuit pattern on the second adhesive resin layer; stacking an insulation board on the substrate such that the second electrode and the second circuit pattern are covered; and forming a third circuit pattern on the insulation board.
A second metal layer can be stacked on the second adhesive resin layer, and in the forming the second electrode and the second circuit pattern, a part of the second metal layer can be etched.
The method can further include desmearing the second adhesive resin layer, prior to the stacking the insulation board. The forming the second electrode and the second circuit pattern can include forming a seed layer on the desmeared second adhesive resin layer; forming a plating resist on the seed layer; forming a plating layer corresponding to the second electrode and the second circuit pattern through electroplating; removing the plating resist; and performing flash-etching such that a part of the seed layer is removed.
The forming the second electrode and the second circuit pattern can be performed before the compressing a surface of the substrate onto a core board. Two substrates can be provided, and the compressing a surface of the substrate onto a core board can be performed on both surfaces of the core board.
Another aspect of the invention provides a method of manufacturing a capacitor-embedded printed circuit board including providing a substrate on which a first adhesive resin layer, a dielectric layer and a second adhesive resin layer are stacked on the order thereof; desmearing the first adhesive resin layer; forming a first electrode and a first circuit pattern on the desmeared first adhesive resin layer through a plating process; compressing a surface of the substrate, on which the first electrode is formed, onto a core board by interposing an insulation resin layer; forming a second electrode and a second circuit pattern on the second adhesive resin layer; stacking an insulation board on the substrate such that the second electrode and the second circuit pattern are covered; and forming a third circuit pattern on the insulation board.
The method can further include desmearing the second adhesive resin layer, prior to the stacking the insulation board. Here, the forming the second electrode and the second circuit pattern can be performed through a plating process.
Also, the forming the second electrode and the second circuit pattern can be performed before the compressing a surface of the substrate on to a core board. Two substrates can be provided, and the compressing a surface of the substrate can be performed on both surfaces of the core board.
Additional aspects and advantages of the present invention will be set forth in part in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention.
These and/or other aspects and advantages will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
Since there can be a variety of permutations and embodiments of the present invention, certain embodiments will be illustrated and described with reference to the accompanying drawings. This, however, is by no means to restrict the present invention to certain embodiments, and shall be construed as including all permutations, equivalents and substitutes covered by the spirit and scope of the present invention. Throughout the drawings, similar elements are given similar reference numerals. Throughout the description of the present invention, when describing a certain technology is determined to evade the point of the present invention, the pertinent detailed description will be omitted.
Terms such as “first” and “second” can be used in describing various elements, but the above elements shall not be restricted to the above terms. The above terms are used only to distinguish one element from the other.
The terms used in the description are intended to describe certain embodiments only, and shall by no means restrict the present invention. Unless clearly used otherwise, expressions in the singular number include a plural meaning. In the present description, an expression such as “comprising” is intended to designate a characteristic, a number, a step, an operation, an element, a part or combinations thereof, and shall not be construed to preclude any presence or possibility of one or more other characteristics, numbers, steps, operations, elements, parts or combinations thereof.
Hereinafter, some embodiments of a capacitor-embedded printed circuit board and a manufacturing method thereof in accordance with an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Those components that are the same or are in correspondence are rendered the same reference numeral regardless of the figure number, and redundant explanations are omitted.
Firstly, a substrate for a capacitor-embedded printed circuit board will be described in accordance with an aspect of the present invention.
The substrate according to the first embodiment can be formed by allowing the adhesive resin layer 12 to be stacked on a surface of the dielectric layer 11. Here, the adhesive resin layer 12 can made of a material capable of being formed with the roughness. At this time, the dielectric layer 11 can be in a semi-hardened status (B-stage) or a hardened status (C-stage).
The adhesive resin layer 12 can be stacked to have a couple of micrometers of thickness on the dielectric layer 11. As described above, the adhesive resin layer 12 suggested by the embodiment can be made of a material capable of being formed with the roughness through desmearing. For example, the material capable of being formed with the roughness can be an adhesive mentioned in the Korean patent publication No. 2007-0078086 (filed by Mitsubishi Gas Chemical Company). Of course, any material capable of being formed with the roughness is applicable.
The adhesive resin layers 12a and 12b, as shown in
This kind of metal layer can be formed on one side surface of the dielectric layer 11 as shown in
Then, a capacitor-embedded printed circuit board in accordance with another aspect of the present invention will be described.
Referring to
In the case of the printed circuit board as shown in
The capacitor-embedded printed circuit board of the above-described structure can minimize the possibility of the delamination that may happen at an area in which the insulation board 31 is stacked by the adhesive resin layer 12′ formed with the roughness, to thereby improve the reliability of products.
Also, forming the adhesive resin layer 12′ as a thin film (having a couple of micrometers of thickness or less) makes it possible to minimize the effect that the adhesive resin layer 12′ has on the performance of the capacitor.
Even though
Hereinafter, the manufacturing method of the capacitor-embedded printed circuit board of the above-described structure will be described in more detail.
Referring to
Firstly, as shown in
At this time, the adhesive resin layer 12 can be formed as a thin film to minimize the effect on the capacitance of the capacitor included in the board. For example, the adhesive resin layer 12 can be formed to have the thickness of 10 um or less.
Then, as shown in
After that, as shown in
Then, as shown in
After the desmearing is performed, the second electrode 14a and the second circuit pattern 14b can be formed on the adhesive resin layer 12′ in a step represented by S150. The second electrode 14a can form the capacitor of the printed circuit board together with the above described first electrode 13a. In other words, if the first electrode 13a acts as the lower electrode, the second electrode 14a can act as the upper electrode. Accordingly, the second electrode 14a can be formed in consideration of the position and size of the first electrode 13a. Below is more detailedly described the method of forming the second electrode 14a and the circuit pattern 14b.
Firstly, as shown in
Then, as shown in
After that, as shown in
As a result, using the plating method to form the second electrode 14a can make it possible to form the electrode having a more accurate size, to thereby arrange the capacity of the capacitor accurately.
After the above-described process forms the second electrode 14a and the second circuit pattern 14b, the insulation board 31 can be stacked on the substrate so as to cover the second electrode 14a and the second circuit pattern 14b in a step represented by S160 and the third circuit pattern 34 can be formed on the insulation board 31 in a step represented by S170.
In addition to the third circuit pattern 34, the via 32 and 33 can be formed to allow each layer to be electrically connected and the solder resist 35 can be formed in the outermost layer to protect the third circuit pattern 34.
Although this embodiment suggests the method of allowing the substrate in which the first electrode 13a and the second circuit pattern 13b are formed to be stacked on the core board 20 and then the second electrode 14a and the second 14b to be formed, as shown
Then, a second embodiment will be described.
Referring to
As compared with the above-described first embodiment, the difference is that the second electrode 14a and the second circuit pattern 14b can be formed by an etching method instead of the plating method in accordance with the second embodiment. The below description related to the embodiment focuses on the difference. The description related to identical or corresponding parts will be omitted.
Firstly, as shown in
Then, as shown in
Next, as shown in
Then, as shown in
After that, as shown in
Although this embodiment suggests the method of allowing the substrate in which the first electrode 13a and the second circuit pattern 13b are formed to be stacked on the core board 20 and then the second electrode 14a and the second 14b to be formed, as shown
Then, a third embodiment will be described.
Referring to
As compared with the above-described first embodiment, the difference is that the adhesive resin layer 12a and 12b can be formed on both surfaces of the dielectric layer 11 in accordance with the third embodiment. The below description related to the embodiment focuses on the difference. The description related to identical or corresponding parts will be omitted.
Firstly, as shown in
After that, as shown in
Some parts of the first metal layer 13 stacked on the first adhesive resin layer 12a can be etched to allow some surface of the first adhesive resin layer 12a to be exposed to the outside. The roughness can be formed on the exposed surface of the first adhesive resin layer 12a. As a result, the formed roughness can make it possible to improve the adhesiveness to the insulation board 31 to be stacked later. This can minimize the possibility of the delamination, to thereby improve the reliability of products.
Then, as shown in
Then, as shown in
After the desmearing is performed, the second electrode 14a and the second circuit pattern 14b can be formed on the second adhesive resin layer 12b in a step represented by S360. Herein, as shown in
Then, as shown in
Although this embodiment suggests the method of allowing the substrate in which the first electrode 13a and the second circuit pattern 13b are formed to be stacked on the core board 20 and then the second electrode 14a and the second 14b to be formed, as shown
Then, a fourth embodiment will be described.
Referring to
As compared with the above-described third embodiment, the difference is that the second electrode 14a and the second circuit pattern 14b can be formed by an etching method instead of the plating method in accordance with the second embodiment. The below description related to the embodiment focuses on the difference. The description related to identical or corresponding parts will be omitted.
Firstly, as shown in
Then, as shown in
Some parts of the first metal layer 13 can be etched to allow some surface of the first adhesive resin layer 12 to be exposed to the outside. The roughness can be formed on the exposed surface of the adhesive resin layer 12. As a result, the formed roughness can make it possible to improve the adhesiveness to the insulation board 31 to be stacked later. This can minimize the possibility of the delamination, to thereby improve the reliability of products.
Then, as shown in
After that, as shown in
Although this embodiment suggests the method of allowing the substrate in which the first electrode 13a and the second circuit pattern 13b are formed to be stacked on the core board 20 and then the second electrode 14a and the second 14b to be formed, as shown
Then, a fifth embodiment will be described
Referring to
As compared with the above-described embodiments, the difference is that the first electrode 13a, the first circuit pattern 13b, the second electrode 14a, the second circuit pattern 14b can be formed by the plating method. The below description related to the embodiment focuses on the difference. The description related to identical or corresponding parts will be omitted.
Firstly, as shown in
Then, as shown in
Then, as shown in
After that, as shown in
Next, as shown in
Although this embodiment suggests the method of allowing the substrate in which the first electrode 13a and the second circuit pattern 13b are formed to be stacked on the core board 20 and then the second electrode 14a and the second 14b to be formed, as shown
Hitherto, although some embodiments of the present invention have been shown and described for the above-described objects, it will be appreciated by any person of ordinary skill in the art that a large number of modifications, permutations and additions are possible within the principles and spirit of the invention, the scope of which shall be defined by the appended claims and their equivalents.
A lot of other embodiments are possible within the principles and spirit of the invention, the scope of which shall be defined by the appended claims and their equivalents.
Number | Date | Country | Kind |
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10-2008-0027551 | Mar 2008 | KR | national |
This application is a divisional of U.S. application Ser. No. 12/320,794, filed Feb. 4, 2009, which claims the benefit of Korean Patent Application No. 10-2008-0027551, filed with the Korean Intellectual Property Office on Mar. 25, 2008, the disclosures of which are incorporated herein by reference in their entirety.
Number | Date | Country | |
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Parent | 12320794 | Feb 2009 | US |
Child | 13403211 | US |