Heat-conductive package structure

A heat-conductive package structure includes a carrier board having a first surface and an opposing second surface and formed with a through opening passing the carrier board; a first heat-conductive structure including a heat-conductive hole in the through opening, a first heat-conductive sheet on the carrier board, and a second heat-conductive sheet on the carrier board, wherein the first and second heat-conductive sheets are conductively connected by the heat-conductive hole; a first dielectric layer formed on the first surface of the carrier board and formed with a first opening for exposing the first heat-conductive sheet; a second dielectric layer formed on the second surface of the carrier board and formed with at least a second opening for exposing a portion of the second heat-conductive sheet; and a second heat-conductive structure formed in the second opening and mounted on the second heat-conductive sheet.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to package structures, and more particularly, to a heat-conductive package structure.

2. Description of Related Art

Owing to advances in semiconductor package technology, there are various packages for semiconductor devices nowadays. Ball Grid Array (BGA) is an advanced semiconductor package technique, characterized by mounting a semiconductor chip on a package substrate, and having a plurality of solder balls arranged in a grid array and formed on the back of the package substrate, thereby increasing the number of I/O connections in unit area. Ball Grid Array not only meets the high integration requirements for a semiconductor chip but also enables the semiconductor chip to be electrically connected to an external device via solder balls.

With the electronic industry booming, electronic products are becoming more multi-function and high-performance. To meet the packaging requirements for high integration and miniaturization of semiconductor packages, semiconductor chips nowadays generate an increasingly great amount of heat during operation. Failure to timely dissipate the heat generated by semiconductor chips can deteriorate the performance of the semiconductor chips and shorten the life of the semiconductor chips.

FIG. 1is a cross-sectional view showing a semiconductor component mounted on a conventional circuit board. The carrier board100has a first surface100aand a second surface100b. The carrier board100is a circuit board with a circuit. The first surface100aand the second surface100bare formed with a first dielectric layer11aand a second dielectric layer11bthereon respectively. The first and second dielectric layers11a,11bare formed with first and second circuit layers12a,12bthereon respectively. The first circuit layer12ahas first electrically connecting pads121aand second electrically connecting pads122athereon. The second circuit layer12bhas third electrically connecting pads121bthereon. At least a plated through hole (PTH)13is formed in the carrier board100and the first and second dielectric layers11a,11bto electrically connect the first and second circuit layers12a,12b. An insulating protective layer14is formed on the first and second dielectric layers11a,11band first and second circuit layers12a,12b. Insulating protective layer openings140,141are formed in the insulating protective layer14to expose the first and second electrically connecting pads121a,122aand third electrically connecting pads121b. A metal protective layer16made of nickel/gold (by nickel-plating and then gold-plating) is formed on the surfaces of the first, second and third electrically connecting pads121a,122aand121b. A conductive element15, such as a solder ball, is formed on the metal protective layer16on the first and third electrically connecting pads121a,121bfor electrical connection with another electronic device. A semiconductor component17is mounted on the insulating protective layer14on the first surface100aof the carrier board100. The semiconductor component17has an active surface17aand an inactive surface17bopposing to the active surface17a. A plurality of electrode pads171are formed on the active surface17aof the semiconductor component17. The semiconductor component17is mounted on the first surface100aof the carrier board100via the inactive surface17b. The second electrically connecting pads122acovered with the metal protective layer16are exposed from the insulating protective layer opening141of the insulating protective layer14. A second conductive element18, such as a metal wire, is formed on the metal protective layer16to electrically connect the electrode pads171on the semiconductor component17and the second electrically connecting pads122a. Afterward, an encapsulant19encapsulates and thereby protects the wire-bonded second conductive element18and semiconductor component17.

Nevertheless, heat generated by the packaged semiconductor component17on the first dielectric layer11ais unlikely to be dissipated efficiently. Also, the inactive surface17bof the semiconductor component17is in contact with the insulating protective layer14, but the insulating protective layer14is almost incapable of heat dissipation. As a result, the semiconductor component17is likely to be overheated and damaged.

FIG. 2Ais a cross-sectional view showing a semiconductor component mounted on another conventional circuit board, in which a carrier board100(like the one shown inFIG. 1) with a first surface100ais provided. An opening110ais formed in a first dielectric layer11adisposed on the first surface100ato expose the carrier board100. An insulating protective layer opening142is formed in the insulating protective layer14disposed on the first dielectric layer11ato expose the second electrically connecting pads122aon the first circuit layer12aformed on the first dielectric layer11aand the opening110aof the first dielectric layer11a. The metal protective layer16is formed on the second electrically connecting pads122a. The inactive surface17bof the semiconductor component17is in contact with a portion of the carrier board100exposed from the opening110a. The second conductive element18electrically connects the electrode pads171on the active surface17aof the semiconductor component17and the metal protective layer16on the second electrically connecting pads122a. The encapsulant19encapsulates and thereby protects the wire-bonded second conductive element18and semiconductor component17. The semiconductor component17is received in the opening110a, so as to reduce the total thickness of the semiconductor package.

The semiconductor component17is embedded in the opening110aof the first dielectric layer11ato shorten an electrical conduction path, lessen signal loss and distortion, enhance high-speed performance, and downsize a wire-bonded and encapsulated semiconductor package. But little heat conduction or heat dissipation takes place through the contact between the carrier board100and the inactive surface17bof the semiconductor component17. As a result, heat generated by the semiconductor component17in operation cannot be efficiently dissipated.

FIG. 2Bis a cross-sectional view showing semiconductor components stacked up and mounted on another conventional circuit board. The semiconductor component17includes a first semiconductor chip17′ and a second semiconductor chip17″ stacked on the first semiconductor chip17′. The first semiconductor chip17′ is mounted on a portion of the carrier board100exposed from the opening110a, via the inactive surface17bof the first semiconductor chip17′. The electrode pads171′,171″ on the first semiconductor chip17′ and the second semiconductor chip17″ are electrically connected to the metal protective layer16on the second electrically connecting pads122a, via the second conductive element18.

The second semiconductor chip17″ is stacked on the first semiconductor chip17′, wherein the inactive surface17b″ of the second semiconductor chip17″ in connected to the active surface17a′ of the first semiconductor chip17′. The first semiconductor chip17′ is mounted on the carrier board100via the inactive surface17b′, but the carrier board100is unfit for heat conductive and heat dissipation. Hence, heat generated by the semiconductor component in operation cannot be efficiently dissipated.

It is an urgent issue to develop a heat-conductive package structure in order to enhance heat dissipation of a semiconductor component in operation, downsize a semiconductor package, and overcome the drawbacks of the prior art.

SUMMARY OF THE INVENTION

In the light of foregoing drawbacks of the prior art, a primary objective of the present invention is to provide a heat-conductive package structure, to enable a semiconductor component to dissipate heat via a heat-conductive structure.

Another objective of the present invention is to provide a heat-conductive package structure, to downsize a semiconductor package and thereby achieve miniaturization of the semiconductor package.

A further objective of the present invention is to provide a heat-conductive package structure, to enhance heat dissipation of the semiconductor component, prevent the semiconductor component and the circuit board from damage, enhance electrical performance of the semiconductor component and the circuit board, and prolong the life of the semiconductor component.

To attain the above and other objectives, the present invention provides a heat-conductive package structure, including: a carrier board with a first surface, a second surface opposing to the first surface, and at least a through opening passing the first and second surfaces; a first heat-conductive structure having a heat-conductive hole in the through opening, a first heat-conductive sheet on the first surface of the carrier board, and a second heat-conductive sheet on the second surface of the carrier board, wherein the first and second heat-conductive sheets are conductively connected by the heat-conductive hole; a first dielectric layer disposed on the first surface of the carrier board and formed with a first opening for exposing the first heat-conductive sheet; a semiconductor component having an active surface and an inactive surface opposing to the active surface, wherein the semiconductor component is mounted on the first heat-conductive sheet via the inactive surface; a second dielectric layer disposed on the second surface of the carrier board and formed with at least a second opening for exposing a portion of the second heat-conductive sheet; and a second heat-conductive structure disposed in the second opening and mounted on the second heat-conductive sheet.

The carrier board is a circuit board with a circuit or an insulated board. The first and second heat-conductive sheets respectively have a metal layer thereon. The heat-conductive hole is one selected from the group consisting of a non-fully plated metal through hole, fully plated metal through hole, solid metal heat-conductive via, and hollow heat-conductive via. The second heat-conductive structure is a hollow heat-conductive via or a solid heat-conductive via.

First and second circuit layers are disposed on the first and second dielectric layers respectively. The first circuit layer has a plurality of first and second electrically connecting pads thereon. The second circuit layer has a plurality of first electrically connecting pads thereon.

An insulating protective layer is disposed on the first and second dielectric layers. An insulating protective layer opening is disposed in the insulating protective layer to expose the first heat-conductive structure in the first opening of the first dielectric layer and expose the first and second electrically connecting pads. A first conductive element, such as a solder ball or a metal pin, is disposed on the first electrically connecting pads in the insulating protective layer opening.

A heat-dissipating element, such as a solder ball or a metal pin, is disposed on the exposed surface of the second heat-conductive structure. The heat-conductive package structure of the present invention further includes a second conductive element for electrically connecting the electrode pads on the semiconductor component and the second electrically connecting pads on the first circuit layer.

The semiconductor component is a chipset having a first semiconductor chip and a second semiconductor chip. The first and second semiconductor chips are active chips or passive chips. A plurality of electrode pads are disposed on the active surfaces of the first and second semiconductor chips. The second conductive element electrically connects the electrode pads on the first and second semiconductor chips and the second electrically connecting pads on the first circuit layer. The second conductive element is a metal wire.

First and second heat-conductive structures are provided for the carrier board and the second dielectric layer. A heat-dissipating element, such as a solder ball or a metal pin, is disposed on the exposed surface of the second heat-conductive structure. A first opening is formed in the carrier board to receive the semiconductor component and enable the semiconductor component to be mounted on the heat-conductive structure. Hence, heat generated by the semiconductor component in operation is transferred to a heat-dissipating element outside the carrier board, via the heat-conductive structure, for heat dissipation. Accordingly, the heat-conductive package structure of the present invention prevents a semiconductor component and a circuit board from being overheated and damaged, and prolongs the life of the semiconductor component and the circuit board.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following illustrative embodiments are provided to illustrate the disclosure of the present invention, these and other advantages and effects can be apparent to those skilled in the art after reading the disclosure of this specification.

FIGS. 3A to 3Fare cross-sectional views showing a method for fabricating a heat-conductive package structure according to the first embodiment of the present invention.

Referring to FIGS.3A and3A′, a carrier board is provided. The carrier board is a circuit board20with a circuit201or an insulated board. The first embodiment is exemplified by a circuit board20with a circuit201. The circuit board20includes a first surface20a, a second surface20bopposing to the first surface20a, and at least a through opening200passing the first surface20aand the second surface20b. In the through opening200, a first heat-conductive structure21ais formed. The first heat-conductive structure21ais not electrically connected to the circuit201and can be a non-fully plated metal through hole, as shown inFIG. 3A. Alternatively, a first heat-conductive structure21a′ is formed in the through opening200, and the heat-conductive structure21a′ can be a fully plated metal through hole, as shown in3A′. The first heat-conductive structure21a,21a′ includes a heat-conductive hole210a,210a′ in the through opening200, a first heat-conductive sheet211a,211a′ on the first surface20aof the carrier board, and a second heat-conductive sheet212a,212a′ on the second surface20bof the carrier board. The first heat-conductive sheet211a,211a′ and the second heat-conductive sheet212a,212a′ are conductively connected by the heat-conductive hole210a,210a′. Hereinafter the first embodiment is exemplified by the first heat-conductive structure21awhich is a plated through hole.

Referring toFIG. 3B, the first surface20aand the second surface20bof the circuit board20are formed with a first dielectric layer22aand a second dielectric layer22brespectively. In the first dielectric layer22a, at least a first opening220ais formed to expose the first heat-conductive sheet211aof the first heat-conductive structure21a. In the second dielectric layer22b, at least a second opening220bis formed to expose a portion of the second heat-conductive sheet212aof the first heat-conductive structure21a.

Referring toFIG. 3C, first and second circuit layers23a,23bare formed on the first and second dielectric layers22a,22brespectively. The first circuit layer23ais formed with a plurality of first electrically connecting pads231aand second electrically connecting pads232a. The second circuit layer23bis formed with a plurality of third electrically connecting pads231b. A second heat-conductive structure21b, such as a heat-conductive via, is formed in the second opening220bof the second dielectric layer22b. The second heat-conductive structure21bis not electrically connected to the second circuit layer23b, but is in contact with the second heat-conductive sheet212aof the first heat-conductive structure21a. A plated through hole233is formed in the circuit board20, first dielectric layer22a, second dielectric layer22b, and first and second circuit layers23a,23bso as to electrically connect the circuit201of the circuit board20and the first or second circuit layer23a,23b.

Referring toFIG. 3D, an insulating protective layer24is formed on the first dielectric layer22aand first circuit layer23a, as well as on the second dielectric layer22band second circuit layer23b, respectively. An insulating protective layer opening240is formed in the insulating protective layer24to expose the first heat-conductive sheet211aof the first heat-conductive structure21ain the first opening220aof the first dielectric layer22a, the surface of second heat-conductive structure21bin the second opening220bof the second dielectric layer22b, and surfaces of the first, second and third electrically connecting pads231a,232a,231b.

Referring toFIG. 3E, a metal protective layer234made of nickel/gold (by nickel-plating and then gold-plating) is formed on the surface of the second heat-conductive structure21band the surfaces of the first, second and third electrically connecting pads231a,232a,231b, and then a heat-dissipating element25, such as a solder ball, is formed on the metal protective layer234on the surface the second heat-conductive structure21b, thereby allowing the heat-dissipating element25to be connected to the second heat-conductive structure21band the first heat-conductive structure21a. A first conductive element26, such as a solder ball, may be formed on the metal protective layer234on the surfaces of the first and third electrically connecting pads231a,231b, wherein the first conductive elements26on the first electrically connecting pads231acan be mounted with one passive component or other package structure (FIG. not shown).

Referring toFIG. 3F, a semiconductor component27is received in the first opening220aof the first dielectric layer22ain which the semiconductor component27is an active chip or a passive chip and includes an active surface27aand an inactive surface27b. The semiconductor component27is mounted on the first heat-conductive sheet211aexposed from the first opening220aof the first dielectric layer22a, via the inactive surface27b. Heat generated by the semiconductor component27in operation is dissipated by the first heat-conductive sheet211a, the heat-conductive hole210a, the second heat-conductive sheet212a, the second heat-conductive structure21b, and the heat-dissipating element25.

The semiconductor component27has a plurality of electrode pads271on the active surface27a. A plurality of second conductive elements28are electrically connected to the metal protective layer234on the second electrically connecting pads232aof the first circuit layer23a. As a result, the semiconductor component27is electrically connected to the first circuit layer23a. An encapsulant29encapsulates and thereby protects the wire-bonded second conductive element28and semiconductor component27.

Referring to FIG.3F′, the semiconductor component27is a chipset having a first semiconductor chip27′ and a second semiconductor chip27″. The first semiconductor chip27′ and the second semiconductor chip27″ are active chips or passive chips. The first semiconductor chip27′ and the second semiconductor chip27″ have a plurality of electrode pads271′,271″ on the active surfaces27a′,27a″ respectively. The electrode pads271′,271″ of the first and second semiconductor chips27′,27″ are electrically connected to the second electrically connecting pads232aon the first circuit layer23avia the second conductive element28.

FIGS. 4A and 4Bare cross-sectional views showing another embodiment of the present invention. Referring toFIG. 4A, the first and second heat-conductive sheets are further formed with a metal layer thereon. Referring toFIG. 4A, the second heat-conductive structure21bis a hollow heat-conductive via. Referring toFIG. 4B, the second heat-conductive structure21b′ is a solid heat-conductive via.

As shown inFIG. 4A, a metal layer202is formed on the circuit201on the first surface20aand the second surface20bof the circuit board20, and the metal layer202covers the first and second heat-conductive sheets211a,212aof the first heat-conductive structure21a. As a result, the metal layer202covers the first and second heat-conductive sheets211a,212aat both ends of the heat-conductive hole210a(the heat-conductive hole210ais, for example, an non-fully plated metal through hole) so as to increase the area of contact between the first heat-conductive structure21aand the semiconductor component27, so as to enhance the efficiency of heat transfer.

Referring toFIG. 4B, the second heat-conductive structure21b′ in the second dielectric layer22bis a solid heat-conductive via, and the first and second heat-conductive sheets211a,212aof the first heat-conductive structure21aare covered with the metal layer202. Thus, the second heat-conductive structure21b′ is mounted on a central portion of the first heat-conductive structure21aso as to increase layout density.

Referring toFIGS. 5A to 5C, which are cross-sectional views of yet another embodiment of the present invention, the first heat-conductive structure is a solid heat-conductive via or a hollow heat-conductive via, and the second heat-conductive structure is a solid heat-conductive via or a hollow heat-conductive via.

Referring toFIG. 5A, a heat-conductive hole210a″ in the circuit board20is a hollow heat-conductive via, and the second heat-conductive structure21bis a hollow heat-conductive via as well. The structural similarity between the heat-conductive hole210a″ and the second heat-conductive structure21bmakes the fabrication process simpler.

Referring toFIG. 5B, the heat-conductive hole210a″ in the circuit board20is a hollow heat-conductive via, and the second heat-conductive structure21b′ is a solid heat-conductive via. Hence, the second heat-conductive structure21b′ enhances the efficiency of heat transfer.

Referring toFIG. 5C, a heat-conductive hole210a′ in the circuit board20is a solid heat-conductive via, and the second heat-conductive structure21b′ is a solid heat-conductive via as well. Thus, the heat-conductive hole210a′ and the second heat-conductive structure21b′ enhance the efficiency of heat transfer.

According to the present invention, a heat-conductive package structure includes a carrier board, a first heat-conductive structure21a, a first dielectric layer22a, a second dielectric layer22b, a first dielectric layer22a, a second dielectric layer22b, a first circuit layer23a, a second circuit layer23b, a semiconductor component27, an insulating protective layer24and a heat-dissipating element25. The carrier board is formed with a circuit201or an insulated board, and has a first surface20a, a second surface20bopposing to the first surface20a, and at least a through opening200passing the first surface20aand the second surface20b. The first heat-conductive structure21ahas a heat-conductive hole210ain the through opening200, a first heat-conductive sheet211aon the first surface20aof the carrier board, and a second heat-conductive sheet212aon the second surface20bof the carrier board, wherein the first and second heat-conductive sheets211a,212aare conductively connected by the heat-conductive hole210a. The first dielectric layer22aand a second dielectric layer22bare disposed on the first surface20aand the second surface20bof the circuit board20respectively, wherein a first opening220ais formed in the first dielectric layer22ato expose the first heat-conductive sheet211a, and at least a second opening220bis formed in the second dielectric layer22bto expose a portion of the second heat-conductive sheet212a. The second heat-conductive structure21bis formed in the second opening220b. The first circuit layer23aand a second circuit layer23bare formed on the first and second dielectric layers22a,22brespectively, wherein the first circuit layer23ais formed with a plurality of first electrically connecting pads231aand second electrically connecting pads232a, and the second circuit layer23bis formed with a plurality of third electrically connecting pads231b. The semiconductor component27is received in the first opening220aof the first dielectric layer22a. The semiconductor component27is an active chip or a passive chip, has an active surface27aand an inactive surface27b, and is mounted on the first heat-conductive structure21aexposed from the first opening220aof the first dielectric layer22avia the inactive surface27b. The insulating protective layer24is formed on the first and second dielectric layers22a,22band the first and second circuit layers23a,23b, and is formed with an insulating protective layer opening240for exposing the first heat-conductive structure21ain the first opening220aof the first dielectric layer22a, the second heat-conductive structure21bin the second dielectric layer22b, and the first, second and third electrically connecting pads231a,232a,231b. The heat-dissipating element25is formed on the second heat-conductive structure21bin the insulating protective layer opening240.

A metal protective layer234made of nickel/gold (by nickel-plating and then gold-plating) is formed on the surface of the second heat-conductive structure21bexposed from the insulating protective layer opening240and the surfaces of the first, second and third electrically connecting pads231a,232a,231b. A first conductive element26, such as a solder ball, is formed on the metal protective layer234on the first and third electrically connecting pads231a,231b. An encapsulant29encapsulates and thereby protects the wire-bonded second conductive element28and semiconductor component27.

The heat-conductive hole210aof the first heat-conductive structure21ais an non-fully plated metal through hole, a fully plated metal through hole, a solid metal heat-conductive via, or a hollow heat-conductive via. The second heat-conductive structure21bis a hollow heat-conductive via or a solid heat-conductive via. The heat-dissipating element25and the first conductive element26are solder balls or metal pins.

According to the present invention, a heat-conductive package structure further includes a metal layer202formed on the circuit201on the first surface20aand the second surface20bof the circuit board20and covering the first heat-conductive structure21a.

According to the present invention, a heat-conductive package structure includes a carrier board formed with first and second heat-conductive structures therein, wherein a semiconductor component is mounted on the first heat-conductive structure. Thus, the heat generated by the semiconductor component in operation is transferred to an external heat-dissipating element by means of the first and second heat-conductive structures. Hence, the present invention provides a heat transfer path for a semiconductor component to enhance heat dissipation of the semiconductor component, prevents the semiconductor component and the circuit board from damage, and enhances electrical performance of the circuit board.

The above embodiments only illustrate the principles of the present invention, and they should not be construed as to limit the present invention in any way. The above embodiments can be modified or altered by those with ordinary skills in the art without departing from the spirit and scope of the present invention as defined in the following appended claims.