KR20090053584A - Printed circuit board embedded with passive elements and manufacturing method thereof - Google Patents

Abstract

The present invention provides a multilayer printed circuit board formed by stacking a plurality of insulating layers and a plurality of conductor layers together, wherein a resistor is formed in a strip shape on a selected insulating layer among the plurality of insulating layers and connected to an input / output terminal through a through hole. A coil pattern is formed in a spiral shape in the conductor layer selected from the plurality of conductor layers, and an inductor formed to connect the input / output terminals of the coil through a through hole, and an upper portion of each of the two conductor layers selected from the plurality of conductor layers, respectively. A multi-layer printed circuit having a passive element circuit formed by combining a capacitor formed by patterning an electrode and a lower electrode to form an interlayer insulator therebetween, and the upper electrode and the lower electrode connected to an input / output terminal through a through hole. Provide a substrate.

Embedded Inductors, Embedded Capacitors, Embedded Resonators, Dielectric Boards, System-on-Packages, SOPs, Multilayer Printed Circuit Boards.

Description

Multi-layer printed circuit board with passive element and manufacturing method {PRINTED CIRCUIT BOARD EMBEDDED WITH PASSIVE ELEMENTS AND MANUFACTURING METHOD THEREOF}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to printed circuit board (PCB) design and manufacturing technology, and includes passive elements including resistors, inductors, or capacitors for implementing an organic system on package (SOP). Furthermore, it further relates to fabrication, structure, placement and application techniques for embedding passive element circuits such as resonators comprised therein into a substrate. The present invention relates to a technology for embedding an inductor and a capacitor in a printed circuit board, which can be applied to a module of a portable device that can secure reliability, mass production, and can be inexpensive and miniaturized.

As information communication systems become smaller and more versatile, the number of integrated circuit chips mounted on system boards increases, and passive devices increase for circuit implementation. Therefore, in order to reduce the size of the printed circuit board by increasing the degree of integration, research has been intensively embedded in the substrate along with the miniaturization, thinning, and integration of passive elements.

Typically, passive elements used in electronic circuit systems may be resistors, capacitors, inductors. Among them, inductors and capacitors occupy a considerable amount of space on the substrate, which can be a major factor in determining the size of electronic system products.

As a method of manufacturing an inductor used in the conventional printed circuit board manufacturing industry, a method of implementing a metal layer on a printed circuit board in a spiral is mainly used. However, in recent years, there has been a problem in using a spiral inductor that occupies a large area in an information communication system that has been miniaturized and complicated in function.

In addition, in the case of a conventional low temperature cofired ceramic inductor, a method of inserting the ceramic inductor into the substrate is applied, which has the advantage of reducing the substrate use area, but due to shrinkage of the ceramic material during the firing process There is a problem in the stability of the manufacturing process and the low yield has technical limitations in mass production.

Meanwhile, in the art, in order to mount a capacitor on a printed circuit board, a chip-type capacitor must be directly mounted on the surface of the substrate (SMT), or in the case of ceramic capacitors, electrodes must be formed in several layers. There is a technical problem. Moreover, in the case of the prior art, the implementation of the high capacity capacitor required for the power supply circuit is not easy.

Accordingly, a first object of the present invention is to provide a technique for embedding a passive element including an inductor and a capacitor in a printed circuit board.

Further, in addition to the first object, a second object of the present invention is to insert a passive element including an inductor and a capacitor into an inner layer of a printed circuit board to reduce the area occupied by the inductor and capacitor on the substrate surface, and relatively to the PCB substrate. It is to provide a technology for mounting a large amount of semiconductor chips.

Further, in addition to the first and second objects, the third object of the present invention is to combine an embedded inductor and a capacitor to form an embedded resonator or a filter, thereby forming an active element and a passive element. It is to provide a technique that can reduce the length of the connection between, reducing the parasitic component and thus improve the electrical performance.

Further, in addition to the first, second, and third objects, a fourth object of the present invention is to provide a printed circuit board manufacturing technology that enables a system on package (SOP).

In order to achieve the above object, in the passive element-embedded printed circuit board according to the present invention, the inductor layer is formed in a spiral pattern between the upper portion of the insulating layer, and the capacitor layer is inherently inserted into the substrate. It is characterized by consisting of a metal-insulator-metal (MIM) -shaped pattern having an upper electrode on the insulating layer having a conductivity and a lower electrode below the insulating layer. In addition, the resonant circuit is configured by connecting an inductor and a capacitor in series or in parallel.

The present invention provides a multilayer printed circuit board formed by stacking a plurality of insulating layers and a plurality of conductor layers together, wherein a resistor is formed in a strip shape on a selected insulating layer among the plurality of insulating layers and connected to an input / output terminal through a through hole. ; An inductor in which a coil pattern is formed in a spiral shape on a selected conductor layer among the plurality of conductor layers, and an input / output terminal of the coil is connected through a through hole; And forming an upper electrode and a lower electrode on each of the two selected conductor layers among the plurality of conductor layers to form an interlayer insulator therebetween, and the upper electrode and the lower electrode are formed to be connected to the input / output terminal through a through hole. A passive element embedded multilayer printed circuit board comprising any one or a combination of capacitors is provided.

The passive element embedded printed circuit manufacturing technology according to the present invention can significantly reduce the area occupied by passive components such as resistors, inductors, and capacitors mounted on the packaging substrate surface by embedding passive elements including inductors and capacitors in the printed circuit board. And, when applied to the production line has the effect of ensuring high reliability and mass production.

In addition, the present invention can mount a large amount of semiconductor chips on a printed circuit board to reduce the size and cost of the multifunctional system. Also. Reduced parasitics to printed circuit boards can improve characteristics and significantly reduce assembly and packaging costs.

Hereinafter, a preferred embodiment of a passive element embedded printed circuit board according to the present invention will be described in detail with reference to the accompanying drawings.

According to the present invention, a printed circuit board including a plurality of insulating layers and a conductor layer does not merely connect signal lines, but passive elements such as an inductor, a capacitor, and a resistor are formed in the printed circuit board to function. Characterized in the functional printed circuit board to perform.

1 is a cross-sectional view of a passive element-embedded printed circuit board according to a preferred embodiment of the present invention.

Referring to FIG. 1, it can be seen that an embedded capacitor 20 is formed using a high dielectric film 10 in a multilayer printed circuit board, and an embedded inductor may be formed by using a conductive hole in one or more layers. 40 and form a resistor 30 using a resistive material.

In addition, as an exemplary embodiment of the present invention, an inductor and a capacitor may be embedded using a film type single device or a micro electromechanical system (MEMS) technology having high capacity and quality factor. Each element is connected through signal lines and performs a function of a band pass filter and a resonator as necessary.

2A, 2B and 2C are diagrams each showing a preferred embodiment of the substrate structure according to the present invention. In the present specification, representative structures of three types of substrates are exemplarily illustrated, but are not necessarily limited thereto.

FIG. 2A shows a structure in which the copper foil layer has eight layers (L1 to L8), wherein a high-k dielectric film 10 for a high frequency capacitor is formed between the L2 layer and the L3 layer and between the L6 layer and the L7 layer.

FIG. 2B is a structure in which the copper foil layer has eight layers (L1 to L8), wherein a high-k dielectric film 10 for high frequency capacitors is formed between the L2 and L3 layers, and a high-capacity capacitor for low-frequency capacitors between the L6 and L7 layers. It is a structure in which the dielectric constant film 15 is formed. FIG. 2C shows a structure in which the copper foil layer has six layers (L1 to L6), and a high dielectric constant film 10 for a high frequency capacitor is formed between the L2 layer and the L3 layer.

3 is a cross-sectional view of a substrate in which a capacitor is embedded in a printed circuit board including a plurality of insulating layers and a conductor layer according to a preferred embodiment of the present invention. Referring to FIG. 3, a high dielectric constant film 10 for a high frequency capacitor is formed between the L2 layer and the L3 layer, an upper electrode 101 is formed on the L2 layer, and a lower electrode 102 is formed on the L3 layer.

The upper electrode 101 and the lower electrode 102 formed as described above have an input terminal and an output terminal through a through hole 301 connecting the L1 layer and the L2 layer, and a through hole 302 connecting the L1 layer and the L3 layer. Will be connected with the In the same manner, using a high-k dielectric film for high frequency or low frequency capacitors formed in the L6 and L7 layers, an upper electrode is formed in the L6 layer and a lower electrode is formed in the L7 layer to connect the L1 and L3 layers. The through hole connecting the L3 layer and the L6 layer and the through hole connecting the L1 layer and the L8 layer are connected to the input terminal and the output terminals.

In a preferred embodiment of the present invention, in order to implement the capacitor as a low frequency high capacity capacitor, the interlayer insulator is manufactured by using a dielectric film having a high dielectric constant, and the capacitor is disposed close to a ground plane conductor layer, In order to implement a high frequency capacitor, it is manufactured using a low loss dielectric, but it is characterized in that it is disposed far from the ground plane conductor layer. The capacitor according to the preferred embodiment of the present invention may be in the form of a metal-insulator-metal (MIM) or a comb finger.

4A, 4B, 4C, and 4D are cross-sectional views of a substrate on which an embedded inductor is formed according to a preferred embodiment of the present invention. Referring to FIG. 4A, a spiral coil 201 is formed in the L1 layer to embed an inductor in the L1 layer, and a signal line 401 is formed in the L3 layer to connect the input terminal and the output terminal. It is connected to the input terminal and the output terminals by using a conductive hole 302 to connect. The inductor according to the present invention includes a vertically stacked inductor that forms a spiral coil inductor in each of the different conductor layers and connects using a through hole.

Referring to FIG. 4B, in order to embed an inductor in the L3 layer, a spiral coil 202 is formed in the L3 layer and connected to the input terminal and the output terminals using a through hole 302 connecting the L1 layer and the L3 layer. do.

Referring to FIG. 4C, in order to embed an inductor in the L5 layer, a conductive coil 203 is formed in the L5 layer, and a through hole 302 connecting the L1 and L3 layers and a through hole connecting the L3 and L6 layers ( 304 is connected to the signal lines, and the other side is connected to the input terminal and the output terminals by using a through hole 303 connecting the L1 layer and the L8 layer.

Referring to FIG. 4D, a spiral coil 201 is formed in the L1 layer and another spiral coil 202 is formed in the L3 layer in order to embed a larger inductor in multiple stages over the L1 and L3 layers. In order to connect two spiral coils in series, a conductive hole 302 connecting the L1 layer and the L3 layer is connected to the input terminal and the output terminals.

According to a preferred embodiment of the present invention, the above-described embedded passive elements may be combined to form a resonator circuit in a printed circuit board.

Fig. 5A shows a cross section of a substrate on which a resonant circuit is formed in accordance with a preferred embodiment of the present invention. Referring to FIG. 5A, a series resonator circuit is implemented by connecting an embedded inductor and a capacitor in series. First, the spiral coil 201 is formed in the L1 layer, two upper electrodes 101 of the capacitor are formed in the L2 layer, and the lower electrode 102 of the capacitor is formed in common in the L3 layer to be used as a connection signal line. In addition, a connection hole 301 connecting the L1 layer and the L2 layer is connected to the input terminal and the output terminal.

5B is a cross-sectional view of a substrate on which a resonant circuit is formed in accordance with another preferred embodiment of the present invention. Referring to FIG. 5B, the conductive electrode 301 is connected to the upper electrode 101 of the capacitor formed in the L2 layer under the input terminal, and the lower electrode 102 of the capacitor formed in the L3 layer is a spiral coil formed in the L3 layer. 202 is connected to form a through hole 302 connecting the L1 layer and the L3 layer.

5C is a cross-sectional view of a substrate on which a resonant circuit is formed in accordance with another preferred embodiment of the present invention. Referring to FIG. 5C, the upper electrode 101 of the capacitor formed in the L2 layer is connected to the upper electrode 101 of the capacitor formed using the through hole 301 under the input terminal, and the capacitor lower electrode 102 formed in the L3 layer connects the L3 layer and the L6 layer. The through hole 304 is connected to the spiral coil 203 formed in the L5 layer, and the through hole 303 connecting the L1 layer and the L8 layer is connected to the output terminal.

6 illustrates an equivalent circuit of a resonant circuit implemented with an embedded capacitor and an inductor according to a preferred embodiment of the present invention. As described above, a circuit consisting of an inductor L and a capacitor C is implemented.

7A is a diagram illustrating a structure in which an LC series connected resonator is configured by connecting an inductor formed in the L1 layer and a capacitor formed over the L2 and L3 layers according to the preferred embodiment of the present invention. FIG. 7B is a diagram illustrating a structure in which an LC series connected resonator is configured by connecting an inductor formed in multiple stages in the L1 and L3 layers and a capacitor formed over the L2 and L3 layers. FIG. 7C shows a three-dimensional structure in which an LC series-connected resonator is formed by connecting an inductor formed in the L5 layer and a capacitor formed over the L2 and L3 layers.

8 shows an equivalent circuit of an LC parallel connected resonator embedded in a substrate according to the present invention. FIG. 9A illustrates a structure in which an LC parallel connected resonator is formed by using an inductor formed in the L1 layer and two capacitors formed in the L2 and L3 layers. FIG. 9B is a diagram illustrating a structure in which an LC parallel connection resonator is configured by connecting an inductor formed in multiple stages in the L1 and L3 layers and a capacitor formed in the L2 and L3 layers.

10A and 10B illustrate equivalent circuits and structures of a diplexer incorporating a passive element in a substrate according to a preferred embodiment of the present invention. An example of configuring a diplexer that performs a function using a passive element and a resonator type formed by the above-described method is shown. Fig. 10B is an exemplary view in which a device having a special purpose function is formed on a printed circuit board using the technique of the present invention. A plurality of embedded inductors and a plurality of embedded capacitors are formed inside the printed circuit board to form a diplexer that filters two frequency bands.

11A is a block diagram showing the configuration of a transmitting and receiving end of a wireless communication device. In the prior art, the configuration of the components of the transmitting and receiving end forms a signal line on an upper portion of a printed circuit board, and mounts passive and active elements on a surface to produce a module that exhibits a function. However, referring to FIG. 11B, in the case of the present invention, the passive elements are all embedded in the printed circuit board according to the technique proposed by the present invention, and only active elements are mounted on the upper portion, thereby effectively reducing the size of the circuit. There is this. As a preferred embodiment of the present invention, a passive element embedded type including a resonator, a filter, a coupler, and a balloon implemented using a capacitor and an inductor may be implemented.

The foregoing has outlined rather broadly the features and technical advantages of the present invention to better understand the claims of the invention which will be described later. Additional features and advantages that make up the claims of the present invention will be described below. It should be appreciated by those skilled in the art that the conception and specific embodiments of the invention disclosed may be readily used as a basis for designing or modifying other structures for carrying out similar purposes to the invention.

In addition, the inventive concepts and embodiments disclosed herein may be used by those skilled in the art as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. In addition, such modifications or altered equivalent structures by those skilled in the art may be variously changed, substituted, and changed without departing from the spirit or scope of the invention described in the claims.

The passive element substrate embedding technology according to the present invention can be applied to system on chip implementation by integrating an inductor or a capacitor into the substrate, thereby increasing the integration density of the substrate, reducing parasitic components and improving high frequency noise characteristics. In addition, the passive element embedded technology according to the present invention can be implemented by applying a series or parallel resonant circuit, thereby enabling the next-generation packaging to enable the low cost, miniaturization, and multifunction of highly reliable information communication components and modules.

1 is a cross-sectional view of a passive element embedded printed circuit board according to a preferred embodiment of the present invention.

2A, 2B and 2C each show a preferred embodiment of the substrate structure according to the present invention.

3 is a cross-sectional view of a substrate incorporating a capacitor in a printed circuit board including a plurality of insulating and conductor layers in accordance with a preferred embodiment of the present invention.

4A, 4B, 4C and 4D are cross-sectional views of a substrate on which an embedded inductor is formed in accordance with a preferred embodiment of the present invention.

5A is a cross-sectional view of a substrate on which a resonant circuit is formed in accordance with a preferred embodiment of the present invention.

5B is a cross-sectional view of a substrate on which a resonant circuit is formed in accordance with another preferred embodiment of the present invention.

5C is a cross-sectional view of a substrate on which a resonant circuit is formed in accordance with another preferred embodiment of the present invention.

6 is an equivalent circuit diagram of a resonant circuit implemented with a built-in capacitor and an inductor according to a preferred embodiment of the present invention.

FIG. 7A illustrates a structure in which an LC series-connected resonator is formed by connecting an inductor formed in the L1 layer and a capacitor formed over the L2 and L3 layers according to the preferred embodiment of the present invention. FIG.

7B is a view showing a structure in which an LC series-connected resonator is constructed by connecting inductors formed in multiple stages in the L1 and L3 layers, and capacitors formed in the L2 and L3 layers.

FIG. 7C illustrates a three-dimensional structure in which an LC series-connected resonator is formed by connecting an inductor formed in the L5 layer and a capacitor formed over the L2 and L3 layers. FIG.

8 illustrates an equivalent circuit of an LC parallel connected resonator embedded in a substrate according to the present invention.

FIG. 9A shows a structure in which an LC parallel-connected resonator is constructed using an inductor formed in the L1 layer and two capacitors formed in the L2 and L3 layers. FIG.

9B is a view showing a structure in which an LC inductor connected resonator is formed by connecting inductors formed in multiple stages in the L1 and L3 layers and capacitors formed in the L2 and L3 layers.

10A and 10B show an equivalent circuit and structure of a diplexer incorporating a passive element in a substrate according to a preferred embodiment of the present invention.

Fig. 11A is a block diagram showing the configuration of a transmitting and receiving end of a wireless communication device.

Fig. 11B is a view showing that the passive elements are all embedded in the printed circuit board, and only active elements are mounted on the upper portion, thereby actually reducing the size of the circuit.

<Explanation of symbols for the main parts of the drawings>

                10: high dielectric constant film

                20: built-in capacitor

                40: built-in inductor

               101: upper electrode

               102: lower electrode

          201, 202: spiral coil

301, 302, 303, 304: through hole

Claims (5)

In a multilayer printed circuit board formed by laminating a plurality of insulating layers and a plurality of conductor layers with each other, A resistor formed in a strip shape on a selected insulating layer among the plurality of insulating layers and connected to an input / output terminal through a through hole; An inductor in which a coil pattern is formed in a spiral shape on a selected conductor layer among the plurality of conductor layers, and an input / output terminal of the coil is connected through a through hole; And A capacitor formed to form an interlayer insulator between the upper electrode and the lower electrode in each of the two selected conductor layers among the plurality of conductor layers, and the upper electrode and the lower electrode connected to the input / output terminal through the through hole. ; Passive device embedded multilayer printed circuit board comprising any one or a combination thereof. The passive printed circuit board of claim 1, wherein the capacitor is in the form of a metal-insulator-metal (MIM) or a comb finger. The method of claim 1, wherein to implement the capacitor as a low-capacity high-capacitance capacitor, the interlayer insulator is fabricated using a dielectric film having a high dielectric constant, and the capacitor is disposed close to a ground plane conductor layer. In order to implement a high-frequency capacitor, a passive element-embedded multilayer printed circuit board, which is manufactured using a low loss dielectric but disposed far from the ground plane conductor layer. The multilayer printed circuit board of claim 1, wherein the inductor includes a vertically stacked inductor that forms spiral coil inductors in different conductor layers and connects through the through holes. 5. The passive printed circuit board of claim 1, further comprising a resonator, a filter, a coupler, and a balloon implemented by using the capacitor and the inductor.

Images