Patent Application
20100006260
This application claims priority under 35 USC §119 to Korean Patent Application No. 2008-67409, filed on Jul. 11, 2008 in the Korean Intellectual Property Office (KIPO), the contents of which are herein incorporated by reference in their entirety.
1. Field of the Invention
Example embodiments relate to a heat sink, a method of manufacturing a heat sink and a memory module including a heat sink. More particularly, example embodiments relate to a heat sink to dissipate a heat generated from a heat generator, a method of manufacturing the heat sink and a memory module including the heat sink.
2. Description of the Related Art
Generally, a memory module includes a printed circuit board, a semiconductor chip provided on the printed circuit board and a heat sink disposed on the semiconductor chip. The heat sink usually has a fin-shaped structure. The weight of the memory module increases because of the heat sink.
When the memory module falls on a ground, cracks may be generated at a joining portion between the printed circuit board and the semiconductor chip because the memory module has a relatively high weight due to the heat sink. Thus, the memory module may be easily damaged or broken.
Meanwhile, the fin-shaped heat sink usually has a relatively low heat dissipating efficiency because this heat sink has a small heat dissipating area although the fin-shaped heat sink has a relatively large size. When the heat sink does not sufficiently dissipate the heat generated from the semiconductor chip, the temperature of the memory module may increase, thereby causing the abnormal operation of the memory module.
Example embodiments provide a heat sink for preventing damage to a memory module including the heat sink while increasing a heat dissipating efficiency thereof.
Example embodiments provide a method of manufacturing a heat sink having an improved heat dissipating efficiency and preventing damage to a memory module including the heat sink.
Example embodiments provide a memory module including a heat sink having an improved heat dissipating efficiency and preventing damage to the memory module.
Additional aspects and utilities of the present general inventive concept will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the general inventive concept
According to the foregoing and other aspects and utilities of the present general inventive concept, there is provided a heat sink including a base plate and at least one elastic plate. The base plate may be connected to a heat generator. The elastic plate may dissipate the heat generated from the heat generator and transmitted through the base plate. One end portion of the elastic plate may be connected to the base plate. The elastic plate may have a zigzag shape to ensure desired elasticity.
The heat generator may include at least one semiconductor chip.
Two elastic plates may be connected to end portions of the base plate, respectively.
The heat sink may further include at least one supporting plate for connecting an end portion of the elastic plate with the base plate.
The elastic plate may include a bent portion having an angulated shape or a round shape.
At least one incision groove may be provided between adjacent elastic plates.
A fixing member may be provided to fix the elastic plate with the heat generator. The fixing member may include at least one clip or at least one adhesion layer.
According to the foregoing and other aspects and utilities of the present general inventive concept, there may also be provided a method of manufacturing a heat sink. In the method of manufacturing the heat sink, a flat plate is prepared. A base plate and at least one elastic plate may be formed by bending the flat plate. The base plate may be connected to a heat generator. The elastic plate may dissipate the heat generated from the heat generator and transmitted through the base plate. One end portion of the elastic plate may be connected to the base plate. The elastic plate may have a zigzag structure.
Two elastic plates may be connected to end portions of the base plate, respectively.
At least one supporting plate may be additionally formed to connecting an end portion of the elastic plates with the base plate.
At least one incision groove may be formed between adjacent elastic plates.
According to the foregoing and/or other aspects and utilities of the present general inventive concept, there may also be provided a memory module. The memory module includes a printed circuit board, at least one semiconductor chip, a heat sink and a fixing member. The printed circuit board may include a connecting pin. The semiconductor chips may be provided on the printed circuit board and may be electrically connected to the printed circuit board. The heat sink may include a base plate and at least one elastic plate. The base plate may cover the semiconductor chip and the elastic plate may dissipate the heat generated from the semiconductor chip and transferred through the base plate. One end portion of the elastic plate may be connected to the base plate. The elastic plate may have a zigzag shape to ensure elasticity. The fixing member may fix the heat sink to the semiconductor chip.
The fixing member may include at least one clip for fixing the heat sink with the semiconductor chip.
The fixing member may include at least one adhesion layer provided between the semiconductor chip and the heat sink.
The memory module may further include at least one supporting plate for connecting an end portion of the elastic plate to the base plate.
The heat sink may include the base plate and the at least one elastic plate having the zigzag structure. When the memory module includes the heat sink, the elastic plate of the heal sink may relieve external impact to prevent the memory module from being damaged. Further, the heat sink includes the elastic plate ensuring a large heat dissipating area, so that the heat sink may have a high heat dissipating efficiency. Accordingly, the malfunction of the memory module due to the increase of temperature may be prevented. Additionally, the base plate and the elastic plate may be simultaneously formed by bending the flat plate, so that a productivity of the heat sink may be enhanced. Furthermore, the memory module including the heat sink may have relatively small dimensions because the heat sink may have a considerably reduced height.
According to still another aspect the foregoing and/or other aspects and utilities of example embodiments the present general inventive concept, there is may also be provided a heat sink including a base plate to be connected to a semiconductor chip, and one or more elastic plates extending from the base plate, having a zigzag structure between end portions of the base plate to dissipate heat generated from the semiconductor chip, and having elasticity in and between the plates to reduce a force exerted on the elastic plates.
The heat sink may further include one or more second elastic plates extending from the base plate and having a zigzag structure between second end portions of the base plate to dissipate heat generated from the semiconductor chip and having elasticity in and between the plates to reduce a force exerted on the elastic plates. One of the one or more elastic plates may be connected to one of the end portions of the base plate, one of the one or more elastic plates may be connected to one of the second end portions of the base plate, and the one or more elastic plates, and the one or more second elastic plates may be spaced apart by a gap formed between the other one of the end portions and the other one of the second end portions of the base plate.
The one or more elastic plates may include a first elastic plate connected to one of the end portions of the base plate and disposed toward the other one of the end portions of the base plate, a second elastic plate extended from the first elastic plate at an angle with the first elastic plate and disposed toward the one of the end portions of the base plate, and a third elastic plate extending from the second elastic plate at another angle with the second elastic plate and disposed toward the other end of the end portions of the base plate. The first, the second, and the third elastic plates may be disposed between the gap and the one of the end portions of the base plate.
According to still another aspect the foregoing and/or other aspects and utilities of example embodiments the present general inventive concept, there is may also be provided a memory module including a printed circuit a board, at least one semiconductor chip disposed on the printed circuit board, a heat sink having a base plate disposed to receive the heat from the at least one semiconductor chip, and one or more elastic plates extended from the base plate, having a zigzag structure between end portions of the base plate to dissipate a heat generated from the semiconductor chip, and having elasticity in and between the plates to reduce a force exerted on the elastic plates, and a fixing member to fix the heat sink with the semiconductor chip.
According to still another aspect the foregoing and/or other aspects and utilities of example embodiments the present general inventive concept, there is may also be provided an electronic apparatus including a main board, and a memory module having a printed circuit board connected to the main board, at least one semiconductor chip disposed on the printed circuit board, a heat sink including a base plate connected to the semiconductor chip, and at least one elastic plate extending from the base plate, having a zigzag structure between end portions of the base plate to dissipate a heat generated from the semiconductor chip, and having elasticity in and between the plates to reduce a force exerted on the elastic plates, and a fixing member to fix the heat sink with the semiconductor chip.
These and/or other aspects and utilities of the present general inventive concept will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
Example embodiments are described more fully hereinafter with reference to the accompanying drawings, in which example embodiments are illustrated. The general inventive concept may, however, be embodied in many different forms and should not be construed as limited to the example embodiments set forth herein. Rather, these example embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the general inventive concept to those skilled in the art. In the drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity.
Reference will now be made in detail to the embodiments of the present general inventive concept, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present general inventive concept by referring to the figures.
It will be understood that when an element or layer is referred to as being “on,” “connected to” or “coupled to” another element or layer, it may be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. Like reference numerals may refer to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
It will be understood that, although the terms first, second, third etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the invention.
Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” may encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Referring to
The printed circuit board 110 includes a connecting pin 112 and a socket latch connecting portion 114. The connecting pin 112 may be provided at one peripheral portion of the printed circuit board 110. For example, the connecting pin 112 may be disposed on one side of the printed circuit board 110. The connecting pin 112 may be electrically connected to a RAM bank 191 on a main board 190 of an electronic apparatus 200. In example embodiments, the connecting pin 112 may include various kinds of controlling pins, address pins, data pins, power pins, etc. The main board 190 of the electronic apparatus 200 may include a circuit to communicate with the one or more semiconductor chips 120 through the connecting pin 112 and the RAM bank 191. The electronic apparatus 200 may have one or more units to perform its function using data stored in the semiconductor chip 120. The memory module 100 may be installed in an inside of the electronic apparatus 200 or may be installed on a housing of the electronic apparatus 200 to be connected to the main board 190. The electronic apparatus 200 may be a computer system, a portable electronic apparatus, a mobile communication apparatus, etc. Since the electronic apparatus 200 is well known, detailed descriptions thereof will be omitted.
The socket latch connecting portion 114 may be coupled to a connector 192 of the main board 190 to prevent the printed circuit board 110 including the connecting pins 112 from being separated from the main board. That is, the socket latch connecting portion 114 may prevent the separation of the printed circuit board 110 relative to the main board having the RAM bank. The socket latch connecting portion 114 may have a hemi circular shape, an elliptical shape, a circular shape, etc., to correspond to the connector 192. The connector 192 may be formed on a housing of the electronic apparatus 200 such the connector 192 and the socket latch connecting portion 114 may be connected when the memory module 100 is installed to the main board 190 in the electronic apparatus 200.
In example embodiments, at least one semiconductor chip 120 may be provided on the printed circuit board 110. For example, one semiconductor chip 120 may be located on one surface of the printed circuit board 110. Alternatively, two semiconductor chips 120 may be disposed on both surfaces of the printed circuit board 120. For example, a first semiconductor chip may be positioned on a first surface of the printed circuit board 120 and a second semiconductor chip may be disposed on a second surface of the printed circuit board 120. Here, the first surface may be disposed opposite to the second surface with respect to the printed circuit board 110, so that the first semiconductor chip may correspond to the second semiconductor chip. Further, more than two semiconductor chips may be provided on one surface of the printed circuit board 110 or both surfaces of the printed circuit board 110.
The connecting member 130 is disposed between the semiconductor chip 120 and the printed circuit board 110. The connecting member 130 may electrically connect the semiconductor chip 120 to the printed circuit board 110. In example embodiments, the connecting member 130 may include a solder ball, a conductive bump, or the like. When two semiconductor chips are positioned on both faces of the printed circuit board 110, two connecting members may be positioned between the semiconductor chips and both faces of the printed circuit board 110, respectively as illustrated in
The heat sink 140 is disposed on the printed circuit board 120 to cover the semiconductor chip 120. For example, when the semiconductor chip 120 is provided on the first surface of the printed circuit board 110, the heat sink 140 may also be disposed on the first surface of the printed circuit board 110 on which the semiconductor chip 120 is positioned. Alternatively, more than two heat sinks 140 may be disposed on both faces of the printed circuit board 110 when more than two semiconductor chips are installed on both faces of the printed circuit board 110. The heat sink 140 may dissipate the heat generated from the semiconductor chip 120 toward an outside.
In example embodiments, the heat sink 140 includes a base plate 142 and an elastic plate 144. The base plate 142 is disposed on the printed circuit board 110 to make contact with the semiconductor chip 120. One end of the elastic plate 144 may be connected to an end portion of the base plate 142. For example, the elastic plate 144 may be integrally formed with the base plate 142. Alternatively, two elastic plates 144-1 and 144-2 may be connected to both end portions of the base plate 142, respectively. Here, the heat sink 140 may be obtained by bending one flat plate to form the base plate 142 and the elastic plates 144 as illustrated in
The elastic plate 144 may include a middle elastic portion 144e1 and an end elastic portion 144e2 disposed in a Z direction, and may also include a first portion 144-1 and a second portion 144-2 disposed in a Y direction. A gap 114g may be formed between the first portion 144-1 and the second portion 144-2 in the Y direction and may be formed in an X direction. The first portion 144-1 and the second portion 144-2 may be spaced apart from each other by a distance corresponding to the gap 114g such that a portion of the fixing member 150 may be inserted into the heat sink 140 through the gap 144g. The portion of the fixing member 150 may not contact the elastic plate 144. However, the present general inventive concept is not limited thereto. It is possible that a portion of fixing member 150 may contact a portion of the heat sink. In this case, heat transfer from the heat sink 140 to the fixing member 150 may be a minimum value not to affect a connecting force of the fixing member 150.
The elastic plates 144e1 and 144e2 may have a plurality of plates connected to have a zigzag structure as illustrated in
In some example embodiments, a plurality of elastic plates may be disposed on the base plate 142. For example, more than two elastic plates may be provided on the base plate 142. Here, the elastic plates may be connected to end portions of the base plate 142 as illustrated in
In example embodiments, the elastic plate 144 may have a zigzag structure. For example, two elastic plates may be formed by bending the flat plate in opposite directions at least two times as illustrated in
The elastic plate 144 may have a relatively large surface area. Accordingly, the heat transferred from the semiconductor chip 120 to the base plate 142 may be effectively dissipated through the elastic plate 144. In addition, the temperature of the semiconductor chip 120 may be maintained to a desirable degree, so that the memory module 100 having the semiconductor chip 120 may properly operate.
In example embodiments, the heat sink 140 may include a material having thermal conductivity. Examples of the material in the heat sink 140 may include metal or plastic. For example, the heat sink 140 may include metal such as copper (Cu), aluminum (Al), platinum (Pt), etc.
The base plate 142 of the heat sink 140 may have a surface area in a plane disposed on the X and Y directions to contact a surface area of the semiconductor chip 120. The surface area of the base plate 132 may be larger than the surface area of the semiconductor chip 120 as illustrated in
Referring to
The fixing member 150 may include a first portion 150a disposed in the Z direction, one or more second portions 150b extended from the first portion 150a in the Y direction, a third portion 150c extended from the corresponding second portions 150b in the Z direction to be inserted in the gap between the elastic plates 144-1 and 144-2, and a fourth portion 150d formed on the third portion 150c to press the base plate 142 toward the semiconductor chip 120. The fourth portion 150d may be a distal end and may be extended along the base plate to increase a connect surface to provide a connection force to the base plate 142 and the semiconductor chip 120. The fixing member 150 may include a plurality of fixing member disposed in the X direction along the memory module 100. The fixing member 150 may have an opening 150 open formed thereon to expose a portion of the heat sink 144 when the fixing member 150 is disposed to cover at least a portion of the heat sink 144 to connect the heat sink 144 to the semiconductor chip 120 and/or the printed circuit board 110.
Before the fixing member 150 is inserted into the gap 144g, the fourth portions 150d may be spaced apart from each other by a first distance. When the fixing member 150 is inserted into the gap 144e and contacts the base plate 142, the fourth portions 150d may be spaced apart from each other by a second distance longer than the first distance to apply a connecting force to the base plate 142 and the semiconductor chip 120.
The third portion 150c of the fixing member 150 may have a length to corresponding to a height of the elastic plate 144 from the base plate 142. The second portion 150b of the fixing member 150 may have a portion to cover at least a portion of the elastic plate 144. The second portion 150b of the fixing member 150 may also have a portion formed with an opening to expose a large area of the elastic plate 144 to increase a dissipation area and efficiency of the heat sink 140.
When the heat sink 140 has elasticity, impact applied to the heat sink 140 may be effectively absorbed even though the memory module 100 falls on a ground. Accordingly, the memory module 100 may be efficiently prevented from being broken or damaged, and the reliability of the memory module 100 may be improved by the heat sink 140 having at least one elastic plate 144.
Referring to
In operation S120, the flat plate is bent to from a heat sink. For example, the flat plate may be bent by a press process using a mold. While bending the flat plate, the flat plate may be transformed to the heat sink that includes a base plate and at least one elastic plate integrally formed with the base plate. When the heat sink is formed by bending one flat plate, the at least one elastic plate may be connected to an end portion of the base plate.
The base plate may be connected to a heat generator such as a semiconductor chip in a memory module. The elastic plate may have a zigzag shape and may provide required elasticity. A bent portion of the elastic plate may have an angulated shape. Therefore, a cross section of the elastic plate may have a shape of Z. The elastic plate may prevent, reduce and/or absorb impact applied to the memory module. Additionally, the heat sink including the elastic plate may outwardly dissipate the heat transferred from the semiconductor chip to the base plate.
According to example embodiments, the base plate and the elastic plate may be simultaneously formed through bending one flat plate as a single monolithic body or a single integrated body. Accordingly, a time required for forming the heat sink may be reduced and a productivity of the heat sink may be improved.
Referring to
The base plate 242 and the elastic plates 244 may have constructions (structure) and functions substantially same as or substantially similar to those of the base plate 142 and the elastic plate 144 illustrated in
Referring to
The first base plate 342a and the second base plate 342b are disposed to be spaced apart from each other by a predetermined distance. Each of the first and the second base plates 342a and 342b may make contact with a heat generator such as a semiconductor chip of a memory module.
In example embodiments, the first elastic plate 344a may connect the first base plate 342a to the second base plate 342b. For example, one end portion of the first elastic plate 344a may be connected to one end portion of the first base plate 342a and the other end portion of the first elastic plate 344a may be connected to one end portion of the second base plate 342b adjacent to the end portion of the first base plate 342a. Additionally, the second elastic plate 344b may be connected to the other end portion of the first base plate 342a and the third elastic plate 344c may be connected to the other end portion of the second base plate 342b.
The heat sink 340 illustrated in
The base plate structure 342 and the elastic plate structure 344 may have constructions (structure) and functions substantially same as or substantially similar to those of the base plate 142 and the elastic plate 144 illustrated in
Since the first elastic plate 344a is spaced apart from the second elastic plate 344b and the third elastic plate 344c by a first gap and a second gap, the fixing member 150 of
Referring to
The base plate 442 and the elastic plates 444 may have constructions (structure) and functions substantially the same as or substantially similar to those of the base plate 142 and the elastic plate 144 described with reference to
The supporting plates 446 include a first portion extended from the elastic plates 444 and a second portion connected to the base plate 442. For example, the supporting plates 446 may be prolonged from the end portions of the elastic plates 444 and may be connected to the base plate 442, respectively. The supporting plates 446 may have a length to corresponding to a height of the elastic plates 444 with respect to the base plate 442. Since the supporting plates 446 support the elastic plates 444, the heat sink 440 may have proper elasticity while improving the intensity of the heat sink 440. Therefore, the heat sink 440 is prevented from being broken or damaged by external impact (force).
Referring to
The processes for forming the flat plate, the base plate and the elastic plates may be substantially the same as or substantially similar to the processes for forming the flat plate, the base plate and the elastic plate described with reference to
Supporting plates for connecting end portions of the elastic plates to the base plate are formed in operation S430. In example embodiments, the supporting plates may be obtained by bending end portions of the elastic plates and then fixing the end portions to the base plate. In accordance with some example embodiment, the supporting plates may be obtained by fixing an additional flat plate to the end portions of the elastic plates and the base plate. The supporting plates may be connected to the elastic plates and the base plate by a welding process or using an adhesive agent.
When the supporting plates support the elastic plates, the heat sink including the supporting plates may have sufficient elasticity and improved structural stability. Thus, a memory module including the heat sink may effectively dissipate the heat generated from a semiconductor chip and may sufficiently endure external impact.
Referring to
In example embodiments, the printed circuit board 510, the semiconductor chip 520 and the connecting member 530 may have constructions (structure) and functions substantially same as or substantially similar to those of the printed circuit board 110, the semiconductor chip 120 and the connecting member 130 described with reference to
The heat sink includes elastic plates 544 (544-1 and 544-2), and the incision grooves 546 may be formed in at least one of the elastic plates 544. At least a portion of the at least one elastic plate 544 may be cut out in the X, the Y, and/or the Z directions to form the incision grooves 546 to expose corresponding portions of the base plate 542. Although
The fixing member 550 may have similar structure to fixing member 150 of
Referring to
The processes for preparing the flat plate and for forming the base plate and the elastic plates may be substantially the same as or substantially similar to the processes for preparing the flat plate and for forming the base plate 142 and the elastic plate described with reference to
Portions of the elastic plate are removed by predetermined distances to form incision grooves between adjacent elastic plates in operation S530. The incision grooves may be formed by a cutting process. The incision grooves 546 may provide spaces for screw combining for at least one clip of a fixing member which fixes the heat sink to a printed circuit board in a memory module. When the clip includes a screw combined through the incision groove, the heat sink may firmly fix a semiconductor chip to the printed circuit board.
After forming the incision grooves or before forming the incision grooves, at least one supporting plate (not illustrated) for connecting end portions of the elastic plates to the base plate may be additionally formed. Further, the process for forming the incision grooves may be omitted when the heat sink fixes the semiconductor chip to the printed circuit board using an adhesive layer.
According to example embodiments, a heat sink may include a base plate and at least one elastic plate having a zigzag structure. When a memory module includes the heat sink, the elastic plate of the heal sink may relieve external impact to prevent the memory module from being damaged. Further, the heat sink includes the elastic plate ensuring a large heat dissipating area, so that the heat sink may have a high heat dissipating efficiency. Accordingly, the malfunction of the memory module due to the increase of temperature may be prevented. Additionally, the base plate and the elastic plate may be simultaneously formed by bending a flat plate, so that a productivity of the heat sink may be enhanced. Furthermore, the memory module including the heat sink may have relatively small dimensions because the heat sink may have a considerably reduced height.
The foregoing is illustrative of example embodiments and is not to be construed as limiting thereof. Although a few example embodiments have been described, those skilled in the art will readily appreciate that many modifications are possible in example embodiments without materially departing from the novel teachings and advantages of the present general inventive concept. Accordingly, all such modifications are intended to be included within the scope of the general inventive concept as defined in the claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Therefore, it is to be understood that the foregoing is illustrative of example embodiments and is not to be construed as limited to the specific example embodiments disclosed, and that modifications to the disclosed example embodiments, as well as other example embodiments, are intended to be included within the scope of the appended claims. The present general inventive concept is defined by the following claims, with equivalents of the claims to be included therein. Although a few embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008-67409 | Jul 2008 | KR | national |
