KR20060099640A - Printed circuit board including heat transfer structure - Google Patents

Abstract

By providing a structure for heat transfer inside the printed circuit board itself, it is possible to efficiently dissipate the heat generated from the component to provide a new structure of the printed circuit board having a high cooling performance while maintaining a thin thickness .

The printed circuit board incorporating the heat transfer structure of the present invention has a conductive wiring pattern for wiring between electronic components formed in at least a portion on an outer surface thereof, and has a sealed inner space, wherein the inner space is provided with heat generated from the electronic component. A PCB body into which a refrigerant causing phase change is injected, and an inner wall surface inserted into an internal space of the PCB body to face an area where at least some of the electronic components are to be disposed, and having a refrigerant therein, and having a capillary force Thereby allowing the wick structure to be in close contact with the at least one wick structure in which fine channels are formed which can provide a passage for the movement of the refrigerant in a direction parallel to the inner wall face, and the inner wall face opposite to the area where at least some of the electronic components are to be placed. At least one support structure having a plurality of through openings for supporting the moving passages of the refrigerant and the vapor Wherein the refrigerant fills at least a portion of the interior space of the PCB body and moves along the wick structure by capillary forces generated in the microchannels inside the wick structure and by heat generated from the electronic component. After vaporizing and moving, it is condensed and circulated in the inner space to perform heat transfer.

Printed circuit board, PCB, heat dissipation, heat transfer, cooling, heat exchange, refrigerant, condensation, vaporization

Description

Printed Circuit Board with Integrated Heat Transfer Structure {PRINTED CIRCUIT BOARD INCLUDING HEAT TRANSFER STRUCTURE}

1 schematically illustrates a configuration and a partial cross section of a printed circuit board according to a first embodiment of the present invention.

2 schematically shows a partial cross-sectional structure of a second embodiment of the present invention.

3 schematically shows a partial cross-sectional structure of a third embodiment of the present invention.

Fig. 4 shows each component constituting the printed circuit board of the first embodiment of the present invention.

Fig. 5 schematically shows the configuration of the fourth embodiment of the present invention in the case where the upper and lower through structures, such as via holes, are formed.

6 schematically shows the configuration of the fifth embodiment of the present invention in the case where the upper and lower through structures, such as via holes, are formed.

7 schematically shows a configuration of a sixth embodiment of the present invention, which is a case where it is applied to a heat sink in a package.

8A to 8B are views illustrating types of wick structures of the present invention.

9A-9F illustrate various examples of support structures of the present invention.

10 shows a seventh embodiment of the invention, in which case the support structure is omitted.

FIG. 11 shows an eighth embodiment of the present invention in the case where protrusions are additionally configured on the inner wall surface of the upper plate or the lower plate.

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

110: top plate 120: bottom plate

112, 113 wick structure 114: support structure

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board incorporating a heat transfer structure, and more particularly, to a structure for heat transfer inside a printed circuit board (PCB) for mounting electric and electronic circuits in various devices and devices. It is for providing a printed circuit board incorporating a heat transfer structure, which is capable of efficiently cooling heat generated from a component mounted on a printed circuit board.

In recent years, with the high integration of semiconductor chips such as memory, central processing unit (CPU), and embedded chips, smooth cooling of chips is becoming more important. In addition, ultra-light weight of mobile electronic products such as notebooks, PDAs, mobile phones, Slimming is in progress. Therefore, printed circuit boards (PCBs) mounted inside such electronic devices and for mounting electronic circuits are gradually miniaturized, and the degree of component integration on the surface thereof is very high.

A typical prior art printed circuit board is provided with a conductor layer on one or both sides of the insulating plate. The conductor layer may be first formed on the entire surface by a method such as deposition and plating to be etched by an appropriate pattern, or may be formed to have a predetermined pattern by a technique such as silk screen printing from the beginning. In the case of a double-sided PCB, a via hole penetrating through an insulating plate is formed to connect a required portion of the conductor pattern on the front side and a required portion of the conductor pattern on the back side.

Such prior art PCBs are made of rigid materials, and some of them are made of flexible materials. Various materials such as resins and ceramics are used for the insulation plate, and resins are also used in many cases including reinforcing base materials such as paper, glass fiber, and glass nonwoven fabric.

As described above, with the recent trend of increasing the integration of electronic components due to the high integration of semiconductor chips and the miniaturization of PCBs, cooling, which has conventionally been sufficient by natural cooling or fan installation, has become a problem. Moreover, installation of a cooling fan is not easy in a small mobile device, and since there is not enough space to circulate air inside, it becomes a problem further. Inadequate cooling of the electronic components resulting from this can shorten the life of the components and lead to malfunction of the equipment.

Therefore, various improvements have been made such as improving the PCB structure itself or adding a separate cooling structure to the PCB for smooth cooling of electronic components mounted on the PCB. In order to improve cooling characteristics by improving the structure of the PCB itself, Korean Patent Laid-Open Publication No. 2002-13920 discloses that a plurality of via holes for heat transfer are provided on a PCB instead of via holes for electrical connection. A PCB structure with a good metal fill configuration is proposed. In addition, Utility Model Registration No. 20-207243 embeds a metal plate inside an insulator plate of a PCB, exposes the place where the electronic component is mounted, and transmits heat generated from the electronic component through the metal plate inside the insulator plate. A PCB structure has been proposed to improve heat transfer efficiency.

In addition, conventional techniques for attaching additional devices such as chassis and thermoelectric elements to the PCB to perform cooling of the PCB, Korean Patent Publication Nos. 10-1985-6302 and 20-1998-54275 And Unexamined Patent Publication No. 1997-53682.

However, the above-described prior art PCB structure has a problem in that there is a limit in heat transfer performance that can be achieved even if the structure of the PCB itself is improved according to the above prior arts, and when an additional structure is added to the PCB, There is a problem that it is difficult to reduce the total volume of components and PCB assemblies.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and includes a structure for heat transfer inside the printed circuit board itself, and the printed circuit board which can efficiently dissipate heat generated from the components mounted on the printed circuit board It is to provide.

In addition, the present invention is to provide a printed circuit board that can maintain a thin thickness while having high cooling performance by efficient heat transfer.

Furthermore, the present invention is intended to enable the formation of a heat transfer structure inside the printed circuit board which can be configured so as not to interfere with the wiring design on the printed circuit board.

In addition, the present invention does not increase the overall volume of a printed circuit board on which various electronic components are mounted, and heat transfer without increasing the area of the printed circuit board or complicated structure for installation of additional components for cooling. The purpose of the present invention is to provide a printed circuit board having a new structure in which a structure is built to obtain high heat transfer efficiency at a low manufacturing cost.

According to the first aspect of the present invention, in order to achieve the above object, in a printed circuit board having a heat transfer structure, a conductive wiring pattern for wiring between electronic components is formed in at least a partial region on the outer surface, and the sealed inner space A PCB body having a refrigerant injected into the internal space causing a phase change by heat generated from the electronic component; A direction inserted in the inner space of the PCB body and in contact with an inner wall surface opposite to an area where at least some of the electronic components are to be disposed, and retaining the refrigerant therein and parallel to the inner wall surface by capillary forces One or more wick structures in which fine channels are formed that can provide a passage for movement of the refrigerant to the reactor; And at least one support structure supporting the wick structure to be in close contact with an inner wall surface facing at least a portion of the electronic components, and having a plurality of through openings for providing a movement passage of the refrigerant and the vapor. Wherein the refrigerant fills at least a portion of the interior space of the PCB body, moves along the wick structure by capillary force generated in the microchannels inside the wick structure and vaporizes by heat generated from the electronic component. After the movement is condensed, it is characterized in that the heat transfer by circulating in the inner space.

By embedding such a heat transfer structure in a printed circuit board, the heat transfer efficiency can be maximized even at a thin thickness, and there is no need to increase the volume by adding another structure on the PCB.

Here, the PCB body, at least the lower portion of the conductive pattern on the surface on which the conductive pattern is formed is preferably made of an insulator material, and consists of an upper plate made of an insulator material, and a lower plate opposite thereto, the upper plate and the lower plate May be implemented by a structure that is sealingly coupled at regular intervals to form the internal space.

In the case of a double-sided PCB, the PCB body is composed of an upper plate made of an insulator material, and a lower plate opposite thereto and made of an insulator material, and the upper plate and the lower plate are sealingly coupled at regular intervals to form the inner space. The conductive pattern may be formed on predetermined surfaces of the outer surface of the upper plate and the outer surface of the lower plate, respectively.

In addition, the PCB body may be made of a material having a predetermined degree or more in order to be used as a flexible PCB.

In the case where a through structure such as a via hole is to be formed, the internal space may be formed within the PCB body such that the internal space is partially present only in a predetermined area required under the outer surface including the area where the electronic component is to be disposed. It may be formed in the shape. In this case, the PCB body may further include at least one via hole penetrating the upper outer surface and the lower outer surface, and the inner space is formed to avoid an area in which the via hole is to be formed.

In addition, the wick structure may be one or more thin plates formed with a plurality of fine parallel patterns penetrating up and down, or may be manufactured by aggregating a plurality of unit fibers to absorb the refrigerant, and a movement passage of the refrigerant by capillary force. In the latter case, the unit fiber is any selected from the group consisting of -OH, -COOH, = O, -NH2, -NH- and = N-. It is characterized in that one hydrophilic group is included in its molecular structure so that it can bind well with water. If necessary, in order to further improve the water retention capacity, the unit fiber may have a non-circular cross-sectional shape, and may have a self-repairing ability. Alternatively, one or more hollows may be formed on the cross section of the unit fiber so that It is also possible to use those having a water-retaining ability, and when water-retaining fine pores, grooves are formed or roughened on the surface of the unit fibers, water-retaining ability can be further increased.

Here, the support structure is preferably a porous structure having vertical and horizontal through-holes for moving the vapor up and down and the liquid refrigerant in the horizontal direction, for example, a square defined on the plate It may be a panel having a plurality of through and embossing patterns in which two opposite sides of the incision are cut and extended and protruded about the other opposite two sides. As another example, as the support structure, a screen mesh may be used, and the number of meshes is about 50 or less based on ASTM specification E-11-95. As another example, the support structure may be any one of a woven fabric, a knit fabric, a fabric, a lace, and a net woven by a fiber bundle formed by aggregating a plurality of unit fibers. In this case, the unit fiber constituting the support structure may be of a structure capable of absorbing the refrigerant itself, the support structure may be to provide a movement passage of the refrigerant therein.

In addition, the PCB body may further include a plurality of groove patterns serving as a movement channel of the refrigerant in at least a portion of a wall surface of the internal space, thereby further promoting circulation of the refrigerant.

According to a second aspect of the present invention, in a printed circuit board having a heat transfer structure, a conductive wiring pattern for wiring between electronic components is formed in at least a partial region on an outer surface thereof, and has a sealed inner space, wherein A PCB body into which a refrigerant causing a phase change is injected by heat generated from an electronic component; A direction inserted in the inner space of the PCB body and in contact with an inner wall surface opposite to an area where at least some of the electronic components are to be disposed, and retaining the refrigerant therein and parallel to the inner wall surface by capillary forces One or more wick structures in which fine channels are formed that can provide a passage for movement of the refrigerant to the reactor; And a wick structure protruding from a portion of an inner wall of the inner space of the PCB body so that the wick structure is in close contact with an inner wall surface opposite to a region where at least some of the electronic components on the opposite side are to be disposed, and moving the refrigerant and the steam. A plurality of protrusions forming a passage therebetween, wherein the refrigerant fills at least a portion of the space inside the PCB body, and the wick structure is formed by capillary force generated in a microchannel inside the wick structure. It moves along and is evaporated and moved by the heat generated from the electronic component and then condensed, it is characterized in that the heat transfer by circulating in the inner space.

By using such a structure, the support structure can be omitted and the manufacturing process can be simplified, wherein the protrusions are preferably circular or polygonal pillars, and are repeatedly formed at predetermined intervals.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 and 4 schematically illustrate a configuration of a printed circuit board according to the first embodiment of the present invention. The illustrated printed circuit board may be manufactured in various shapes and dimensions according to the type, characteristic, and specific circuit design of the circuit to be mounted, and the type and design of the electronic device on which the printed circuit board is to be mounted. In general, various types of heat generating electronic components (1, 2) and the like (1, 2) are mounted on a printed circuit board as illustrated. If necessary, a connection terminal portion or the like that can be mounted in a slot such as a computer may be appropriately disposed. A predetermined conductive wiring pattern 3 is formed on the surface of the PCB body 100, and the contents of the specific pattern vary in various ways depending on the design of the circuit. The conductive pattern may be formed only on the upper surface of the PCB body 100, formed on both upper and lower surfaces (both sides PCB), or may be formed by stacking several layers (multilayer PCB) inside the PCB body.

In this embodiment, as shown in the cross-sectional view of Figure 1, the heat transfer structure is embedded in the PCB body 100, for this purpose, a predetermined internal space 116 is formed in the PCB body 100. The inner space 116 is sealed from the outside air and is preferably maintained at a lower pressure than the atmospheric pressure for active vaporization of the refrigerant. The thickness of the portion of the upper plate 110 constituting the inner wall of the inner space 116 should be appropriately determined in consideration of insulation, mechanical strength, and smooth transfer of heat generated from the electronic component 1 mounted on the outer surface. When the upper plate 110 is made of synthetic resin, the thickness thereof is preferably 2 mm or less in order to obtain good heat transfer characteristics.

In order to form the inner space 116 and facilitate assembly of components inserted therein, the PCB body 100 may be configured by bonding the upper plate 110 and the lower plate 120. On the inner wall of the upper plate 110 of the inner space 116, the refrigerant is retained by using a plurality of microchannels formed therein, and the refrigerant is moved (L) in the direction of the heat source by capillary force. The wick structure 112 is continuously provided.

In order to obtain good cooling characteristics, the wick structure 112 must be in close contact with the inner wall of the upper plate 110, and also the movement of the refrigerant that has been vaporized and condensed back into the liquid phase so that vaporized vaporized by the heat source can move well. The passage (V) should be well formed. Thus, while the wick structure 112 is in close contact with the inner wall of the upper plate 110, the support structure 114 having a plurality of through openings to provide a moving passage of the refrigerant in the vaporized vapor state and the refrigerant condensed in the low temperature portion is The internal space 116 of the PCB body 100 is installed. In the structure illustrated in FIG. 1, a screen mesh is used as the support structure 114, but is not limited thereto. A support structure 114 having various structures to be described in detail below may be used.

As shown in the cross-sectional view, the refrigerant is supplied in the direction of the heat source (L) by the capillary force of the microchannel formed inside the wick structure 112, and vaporized (V) near the heat source to support the structure in the vapor state Through the through-holes formed in the 114 to the low temperature portion, it is condensed back to the liquid phase in the low temperature portion is circulated through the wick structure 112. Therefore, the heat transfer structure formed inside the PCB body 100 of the present invention will release heat by the self-circulation of the refrigerant even if a separate heat exchange device or the like does not exist.

The PCB body 100 having the upper plate 110, the lower plate 120, the wick structure 112, and the support structure 114 may be formed to have a very thin thickness. When adopting the structure of the present invention, the PCB body 100 can be formed to a total thickness of 5mm or less (preferably 2mm or less), so that the thickness is greatly increased compared to the conventional PCB substrate having no such heat transfer structure at all. It is possible to obtain high cooling performance without work.

In addition, in the present invention, the PCB itself serves as a kind of heat sink, and the electronic components such as the IC 1 mounted on the PCB of the present invention do not need to attach a structure such as a heat sink separately. The entire PCB with components mounted can be further reduced in volume. If necessary, a thermally conductive paste, an adhesive, or the like may be applied to improve contact between the electronic component such as the IC 1 and the PCB to facilitate heat transfer.

2 schematically shows a cross-sectional structure of a second embodiment of a PCB of the present invention. In the illustrated embodiment, the insulating layer 105 is formed on the upper surface of the upper plate separately, and the electronic component 1 is mounted on the insulating layer 105. Therefore, it is possible to further improve the heat transfer characteristics by configuring the upper plate 110 of the PCB body 100 made of a metal having a high heat transfer coefficient. At this time, in some cases, a pattern is formed in the insulating layer 105 so that the insulating layer 105 does not exist in the region where the electronic component 1 such as the IC is to be mounted, whereby the lower end of the electronic component 1 such as the IC and the The upper end of the upper body 110 of the PCB body 100 may be configured to be in direct contact, thereby further improving heat transfer characteristics. Since other configurations are the same as those in the first embodiment described above, further description thereof will be omitted.

3 schematically shows the cross-sectional structure of a third embodiment of a PCB of the present invention. The illustrated embodiment is a double-sided PCB, in which predetermined conductive wiring patterns 3 and 13 are formed on both the upper and lower surfaces of the PCB body 100, and the electronic components 1, 11, and 15 are connected to each other. The configuration is shown. In this case, the wick structures 112 and 113 are in close contact with the inner walls of the upper plate 110 and the lower plate 120 of the PCB body 100 to supply the refrigerant to the heat sources respectively present on the upper and lower surfaces through the respective wall surfaces. It can be done. Here, too, the refrigerant is supplied by capillary forces in the microchannels formed in the wick structures 112 and 113. The support structure 114 provided between the wick structures 112 and 113 on both sides adheres the two wick structures 112 and 113 to the respective walls, thereby providing a plurality of through openings present on the support structure 114. Through the vaporized refrigerant and the condensed refrigerant to communicate and circulate.

5 schematically shows a configuration of a fourth embodiment of the present invention. The drawing illustrates a planar structure of the internal space 116 of the PCB body 100 when the via hole P is formed. As illustrated, the inner space 116 may be appropriately disposed in the PCB body in a predetermined pattern to avoid portions in which the via hole P is to be formed. In the lower part of FIG. 5, a partial cross-sectional structure (cut line B-B ') of this internal space is shown. The wick structures 112 and 113 are arranged to correspond to the shape of the above pattern, so that the support structure 114 is also arranged between the wick structures and the support structure 114 is arranged to correspond to the shape of the above pattern. The upper and lower plates 112 and 113 are brought into close contact with the surfaces of the upper plate 110 and the lower plate 120, and vaporized refrigerant and condensed refrigerant circulate through the through openings in the support structure 114, and the wick structure 1120. 113) The refrigerant is supplied to the heat source by the microchannels present therein.

6 schematically shows a configuration of a fifth embodiment of the present invention. FIG. 6 is an embodiment corresponding to the case where the via holes P are present on the substrate body as in the case of FIG. 5, and also avoids an area in which the via holes P are disposed. 116 is formed, and the wick structures 112 and 113 and the support structure 114 corresponding to the internal space 116 pattern are mounted in the internal space 116. 6 is a partial cross-sectional view (cut line C-C ') at the bottom of FIG.

7 schematically shows a configuration of a sixth embodiment of the present invention. The illustrated embodiment shows a case in which the present invention is applied to the structure of the heat sink 210 in the semiconductor package. The semiconductor chip 201 integrated in the package may be an LED, a power semiconductor, a communication device, or an integrated circuit. The illustrated package structure is a general structure in which the semiconductor chip 201 is mounted on the heat sink 210 by the bonding layer 205 and connected to the lead terminal 204 by the wire 203, and the wire 203 is provided. There is a resin molding layer 206 that encapsulates a portion of the lead frame 204 and the semiconductor chip 201. At this time, the heat sink 210 forms a part of the entire package, and as shown therein, the wick structure 212 and the support structure 214 is present. The circulating action of the refrigerant by the wick structure 212 and the support structure 214 inside the heat sink 210 is the same as in the other embodiments described above.

8A-8B illustrate the wick structures 112, 113 of the present invention. The wick structures 112 and 113 may be made of any material or structure as long as the wick structures 112 and 113 are configured to move the refrigerant by capillary force generated in the fine channels existing therein.

The illustrated wick structure 112 of FIG. 8B forms a plurality of narrow parallel patterns and utilizes the gaps between the parallel patterns as microchannels through which capillary forces can be generated. To illustrate. The gap between the parallel patterns of the illustrated wick structure 112 is preferably between several tens of nanometers and several micrometers, and such narrow parallel patterns may be processed by a method such as machining or etching. In this case, the material of the wick structure 112 may be selected from a variety of materials, such as metal, synthetic resin, ceramics as needed.

In addition, the wick structure 112 illustrated in FIG. 8A is made of a material that itself has a water retention capability. For example, it refers to a structure such as pulp, paper, woven fabric or nonwoven fabric, which is composed of a collection of fine fibers and whose material itself is capable of absorbing and retaining a refrigerant such as water therein. In order to increase, the fine fibers themselves have a property of absorbing and repairing (the case of such a structure is defined as 'hydrophilic wick structure' in the present invention) may be used. When the hydrophilic wick structure is used, since the structure itself has absorption and repair characteristics, a refrigerant such as water quickly penetrates into the structure without any pretreatment such as hydrophilic treatment, and remains in the structure. Will be carried.

The fiber constituting the hydrophilic wick structure has a hydrophilic group, -OH, -COOH, = 0, -NH2, -NH-, = N-, etc., on the surface thereof, so that the fiber can be combined with water well. Or, there is a hole (H) in the cross section of the fiber by the capillary force through the hole to absorb moisture and repair the fiber itself, or the cross-section is not a simple circular structure, it is made of various shapes to repair It may have a possible structure, or grooves or fine grooves may be formed on the fiber surface to enhance absorption and repair ability. Furthermore, even in the case of carbon nanotubes, which have recently been expanded in their application range, the hydrophilic structure of the present invention is extremely high because the surface area is extremely large, light weight, and a sufficient volume of hollows are formed therein. Can be used as the material of the wick.

With this high refrigerant absorption and repair capability, the hydrophilic wick structure of FIG. 8A enables supply of sufficient refrigerant to the heat source, no dry out, and gravity when the PCB is tilted. This can eliminate the possibility of dry out due to the effect. In addition, even when the wick structure is thin, a sufficient amount of refrigerant can be absorbed, thereby making it possible to make the entire PCB thinner. Furthermore, the wick structure itself has sufficient flexibility, and even if it is bent, the absorbency and water retention of the wick structure are less likely to be deteriorated, so that high heat transfer performance can be maintained even if the PCB length is increased (eg, For example, a copper wick structure: Young's ratio is about 12,200kg / mm2; Hydrophilic wick structure: Young's ratio is about 100-3000kg / mm2).

At the bottom of FIG. 8A is a partially enlarged electron micrograph of the illustrated wick structure 112. As described above, the illustrated wick structure 112 is composed of a collection of fine fibers (F), preferably, each fine fiber (F) has a structure capable of self-absorption and repair, such as hollow, gaps, grooves, etc. It may be provided with fibers. In addition, a microchannel is formed between the fiber and the fiber to maximize the capillary force which is the driving force of the refrigerant movement through it, and when the wick structure 112 is pressed by the support structure 114, the fiber and the fiber becomes more dense The capillary force is further increased. In addition, when the wick structure is wet with water, the upper wall and the lower plate is in close contact with the inner wall surface is very excellent heat transfer characteristics.

In addition, the hydrophilic wick structure 112 is much cheaper than the micro-channel thin plate structure or screen mesh of FIG. 8a in terms of manufacturing cost, so that the manufacturing cost can be significantly lowered, and is a very light material. It is possible to reduce the weight of the electronic product mounted with the PCB.

9A-9F illustrate various examples of support structures of the present invention.

9A illustrates a support structure 610 in which a straight pattern is formed parallel to the longitudinal axis of the support structure. In addition, FIG. 9B shows an example in which two support structures 710 and 712 are formed in which a straight line pattern parallel to the longitudinal axis is formed on one side and a straight line pattern parallel to the main axis direction is formed on the other side. .

9C illustrates a case in which a screen mesh having an edge at the edge is used as the support structure 810. Figure 9d also shows a screen structure with no edges at the edges and woven so that the wires in the longitudinal and principal axes cross each other, or the wires in the upper layer are arranged in the axial direction and the wires in the lower layer in the longitudinal axis. The case used at 910 is shown.

FIG. 9E illustrates a case of using a porous structure having a plurality of horizontal through openings 1013 and vertical through openings 1012 as the supporting structure 1010. In such a structure, the vapor or condensed refrigerant generated by the heat source is moved between the upper and lower portions by the vertical through openings 1012, and is moved left and right by the horizontal through openings 1013. It is possible to provide both a path of movement of the vapor and the refrigerant. The diameter of the through-holes in the vertical direction for the movement of steam is 0.5 to 4 mm, and the diameter of the through-holes in the horizontal direction for the movement of the refrigerant is 10 to 300 um. A relatively large one is desirable to prevent clogging.

9F illustrates a support structure 1110 in the form of an embossing pattern on the plate. The support structure 1110 of this type is arranged by arranging fine embossing structures in which two opposite sides in a fine rectangular region on the plate are cut and the other opposite sides are extended to protrude in one direction. Each of the fine embossed structures includes an opening 1113 providing a passage for moving the steam and a protrusion 1112 for securing a horizontal movement space of the steam between the upper plate while receiving the pressure applied by the upper plate. )

10 shows a seventh embodiment of the present invention. In the illustrated embodiment, the wick structure 112 is in close contact with the inner wall surface of the PCB upper plate 110, the same as the case of the second embodiment described above, but does not use a separate support structure, There is a difference in that the plurality of protrusions 122 are formed on the upper surface so that the plurality of protrusions 122 support the wick structure 112 to be in close contact with the inner wall surface of the upper plate 110. The shape of the plurality of protrusions may be used in any geometric shape, and may be a movement and circulation of the vaporized refrigerant and the condensed refrigerant through the space between the protrusion and the projection. In addition, the wick structure 112 may also be any of those listed above.

11 shows an eighth embodiment of the present invention. As shown in the eighth embodiment, as necessary, fine grooves 118 may be further formed on the inner wall surface of the upper plate 110 or the lower plate 120 to which the wick structure 112 is in close contact. As such, when the fine groove 118 is formed on the inner wall surface of the upper plate 110 or the lower plate 120, the refrigerant can be supplied by capillary force even through the fine groove 118 together with the wick structure 112. It is possible to increase the reliability of heat transfer.

In order to implement a flexible PCB with flexibility, the upper plate 110 and the lower plate 120 may be made of a flexible polymer material. In this case, the wick structures 112 and 113 and the support structure 114 are also preferably made of a flexible material.

The printed circuit board incorporating the heat transfer structure according to the present invention can be modified and applied in various forms within the scope of the technical idea of the present invention and is not limited to the above preferred embodiment. For example, the planar shape of the device may be embodied in various polygonal or free-formed shapes as well as those of the illustrated rectangle, and the wick structure or the supporting structure may be used by overlapping several sheets.

In addition, the embodiments and drawings are merely for the purpose of describing the contents of the invention in detail, and are not intended to limit the scope of the technical idea of the invention, the present invention described above is common knowledge in the technical field to which the present invention belongs As those skilled in the art can have various substitutions, modifications, and changes without departing from the spirit and scope of the present invention, it is not limited to the embodiments and the accompanying drawings. And should be judged to include equality.

According to the present invention, a structure for heat transfer is provided within the printed circuit board itself, so that heat generated from a component mounted on the printed circuit board can be efficiently dispersed.

In addition, according to the present invention, it is possible to provide a printed circuit board having a new structure capable of maintaining a thin thickness while having high cooling performance by efficient heat transfer.

Further, according to the present invention, it is possible to form a heat transfer structure inside the printed circuit board without disturbing the wiring design on the printed circuit board.

In addition, according to the present invention, without increasing the total volume of the printed circuit board mounted with various electronic components, without increasing the area of the printed circuit board or complicated structure for the installation of additional components for cooling, By using a printed circuit board incorporating a heat transfer structure, it is possible to obtain high heat transfer efficiency at a low manufacturing cost.

Claims (21)

A PCB body having a conductive wiring pattern for wiring between electronic components formed in at least a portion of an outer surface thereof, having a sealed inner space, and into which the refrigerant causing a phase change by heat generated from the electronic component is injected; A direction inserted in the inner space of the PCB body and in contact with an inner wall surface opposite to an area where at least some of the electronic components are to be disposed, and retaining the refrigerant therein and parallel to the inner wall surface by capillary forces One or more wick structures in which fine channels are formed that can provide a passage for movement of the refrigerant to the reactor; And The wick structure supports the wick structure to be in close contact with an inner wall surface facing at least a portion of the electronic components, and includes at least one support structure having a plurality of through openings for providing a passage of the refrigerant and the vapor; , The refrigerant fills at least a portion of the interior space of the PCB body, moves along the wick structure by capillary force generated in the microchannels inside the wick structure, and is vaporized and moved by heat generated from the electronic component. And then condensed to circulate in the interior space to perform heat transfer. The method of claim 1, The PCB body is A printed circuit board incorporating a heat transfer structure, characterized in that the lower portion of the conductive pattern on the surface on which the conductive pattern is formed is made of an insulator material. The method of claim 2, The PCB body is And a top plate made of an insulator material and a bottom plate opposite thereto, wherein the top plate and the bottom plate are sealed at regular intervals so that the inner space can be formed. The method of claim 2, The PCB body is It consists of an upper plate made of an insulator material, and a lower plate opposed to the lower plate made of an insulator material, and the upper plate and the lower plate are sealed at regular intervals so that the inner space can be formed, and the outer surface of the upper plate and the outer surface of the lower plate. The printed circuit board incorporating a heat transfer structure, characterized in that the conductive pattern is formed in each of predetermined regions. The method of claim 1, The PCB body is A printed circuit board with a built-in heat transfer structure, characterized by being made of a material having a predetermined degree or more of flexibility in order to be used as a flexible PCB. The method of claim 1, The inner space is formed in an arbitrary shape in the PCB body so that it partially exists only in a predetermined region required under the outer surface including the region where the electronic component is to be disposed, Built-in printed circuit board. The method of claim 6, The PCB body further includes one or more via holes penetrating the upper outer surface and the lower outer surface, And the inner space is formed to avoid an area in which the via hole is to be formed. The method of claim 1, The wick structure, A printed circuit board incorporating a heat transfer structure, characterized in that at least one thin plate formed with a plurality of fine parallel patterns penetrating up and down. The method of claim 1, The wick structure, It is manufactured by aggregating a plurality of unit fibers, can absorb the refrigerant, and has a plurality of fine channels therein for providing a movement passage of the refrigerant by capillary force, printing with a built-in heat transfer structure Circuit board. The method of claim 9, The unit fiber may include any one hydrophilic group selected from the group consisting of -OH, -COOH, = O, -NH2, -NH-, and = N- in its molecular structure to be able to bind with water well. Printed circuit board with built-in heat transfer structure. The method of claim 9, The unit fiber has a non-circular cross-sectional shape and has a self-maintenance capability. The printed circuit board having a heat transfer structure. The method of claim 9, The unit fiber is a printed circuit board having a heat transfer structure, characterized in that one or more hollows are formed on the cross section has a self-maintenance capacity. The method of claim 9, The unit fiber is a printed circuit board with a heat transfer structure, characterized in that the fine pores, grooves (groove) formed on the surface or roughened. The method of claim 1, And the supporting structure is a porous structure having vertical and horizontal through openings for moving the vapor up and down and moving the liquid refrigerant in the horizontal direction. The method of claim 1, The support structure is a printed-embedded heat transfer structure, characterized in that the panel having a plurality of through and embossed patterns in which two opposite sides of a square defined on the plate are cut and extended and protruded about the other opposite two sides. Circuit board. The method of claim 1, The support structure is a screen mesh (screen mesh), the number of mesh is 50 or less based on ASTM specification E-11-95, The printed circuit board with a heat transfer structure. The method of claim 1, The support structure is a printed circuit board with a heat transfer structure, characterized in that any one of a woven fabric, knitted, fabric, lace and net woven by a bundle of a plurality of unit fibers. The method of claim 17, The unit fiber constituting the support structure is a structure that can itself absorb the refrigerant, the support structure is to provide a movement passage of the refrigerant therein, the built-in heat transfer structure Printed circuit board. The method of claim 1, The PCB body further comprises a plurality of groove patterns serving as a movement channel of the refrigerant in at least a portion of the wall surface of the inner space, the printed circuit board with a heat transfer structure. A PCB body having a conductive wiring pattern for wiring between electronic components formed in at least a partial region on an outer surface thereof, and having a sealed inner space, into which the refrigerant causing a phase change by heat generated from the electronic component is injected; A direction inserted in the inner space of the PCB body and in contact with an inner wall surface opposite to an area where at least some of the electronic components are to be disposed, and retaining the refrigerant therein and parallel to the inner wall surface by capillary forces One or more wick structures in which fine channels are formed that can provide a passage for movement of the refrigerant to the reactor; And Protrudes from a portion of an inner wall of the inner space of the PCB body to support the wick structure to be in close contact with an inner wall surface opposite to a region where at least some of the electronic components on the opposite side are to be disposed, and to support the movement path of the refrigerant and the vapor; It includes a plurality of projections formed between each, The refrigerant fills at least a portion of the interior space of the PCB body, moves along the wick structure by capillary force generated in the microchannels inside the wick structure, and is vaporized and moved by heat generated from the electronic component. And then condensed to circulate in the interior space to perform heat transfer. The method of claim 20, The protrusions are circular or polygonal pillar-shaped, it characterized in that formed repeatedly at a predetermined interval, the printed circuit board with a heat transfer structure.

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