JP2021158190A - Electronic device and vapor chamber - Google Patents

Abstract

To provide an electronic device capable of relieving stress when a vapor chamber or a substrate is bent.SOLUTION: An electronic device 100 includes a substrate 110, a heat generating element 111 arranged on the upper surface 110a of the substrate 110, a shield case 112 arranged so as to surround the heat generating element 111 and having an opening 112b, and a vapor chamber 120 facing the upper surface 110a of the substrate 110 and directly or indirectly joining the heat generating element 111 via an opening 112b, and the vapor chamber 120 includes a chamber main body 123 having a housing 123a, a hydraulic fluid sealed in the housing 123a, and a wick arranged in the housing 123a, and a shield portion 121 arranged in the housing 123a. The shield case 112 and the shield portion 121 are combined.SELECTED DRAWING: Figure 1

Description

The present invention relates to electronic devices. The present invention also relates to a vapor chamber.

In recent years, the amount of heat generated has increased due to the high integration and high performance of devices. In addition, as the miniaturization of products progresses, the heat generation density increases, so heat dissipation measures have become important. This situation is particularly noticeable in the field of mobile terminals such as smartphones and tablets. As the heat countermeasure member, a graphite sheet or the like is often used, but since the heat transport amount thereof is not sufficient, the use of various heat countermeasure members is being considered. Above all, the use of a vapor chamber, which is a planar heat pipe, is being studied because it can diffuse heat very effectively.

The vapor chamber is a flat plate-shaped airtight container filled with an appropriate amount of a working liquid that easily volatilizes. The working liquid is vaporized by the heat from the heat source, moves in the internal space, and then releases heat to the outside to return to the liquid. The hydraulic fluid that has returned to liquid is carried to the vicinity of the heat source again by a capillary structure called a wick, and vaporizes again. By repeating this, the vapor chamber operates independently without having external power, and can diffuse heat two-dimensionally at high speed by utilizing the latent heat of vaporization and the latent heat of condensation of the working liquid.

Patent Document 1 describes a vapor chamber for cooling a device to be cooled mounted on a substrate, which is on a side opposite to a sealed space in which a working liquid is sealed and a surface of the device to be cooled that is mounted on the substrate. Described is a vapor chamber comprising a mounting surface to be mounted on the surface, a chamber body that receives the heat of the device to be cooled, and a heat conductive portion that conducts the heat of the chamber body to the substrate. There is. Further, in Patent Document 1, the heat conductive portion is continuously formed over the entire circumference and electrically connected to the ground electrode to have a ground potential, thereby imparting a function as a magnetic shield to the heat conductive portion. It is also stated that.

Patent Document 2 describes a circuit board, an electronic component element having a large heat generation mounted on the upper surface of the circuit board, a plurality of terminal electrodes formed on the lower surface of the circuit board and joined to the motherboard, and an upper surface of the circuit board. In a surface mount type electronic component composed of a shield case covering the above, the inner surface of the shield case and the electronic component element having a large heat generation are joined, and a metal is formed between the upper surface of the circuit board and the inner surface of the shield case. A surface mount electronic component is described, characterized in that the supports are joined.

JP-A-2018-162949 Japanese Unexamined Patent Publication No. 2003-283168

In the vapor chamber described in Patent Document 1, the heat of the chamber body is conducted to the substrate by the heat conductive portion, so that the heat of the chamber body can be released to the substrate. Therefore, it is said that the heat transport efficiency of the vapor chamber can be improved.

In the surface mount type electronic component described in Patent Document 2, the heat generated from the electronic component element having high heat generation is transferred to the shield case, and a part of the heat of the shield case is transferred to the metal support. .. Therefore, it is said that the heat conduction path is dispersed and the heat transfer path becomes long, so that the thermal resistance of the electronic component element having high heat generation becomes small.

However, when the vapor chamber or the substrate described in Patent Document 1 is bent, the stress applied to the heat conductive portion is not relaxed and is accumulated in the heat conductive portion. Similarly, when the shield case or circuit board described in Patent Document 2 is bent, the stress applied to the metal support is not relaxed and is accumulated in the metal support.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an electronic device capable of relieving stress when a vapor chamber or a substrate is bent. Another object of the present invention is to provide a vapor chamber used in the above-mentioned electronic device.

The electronic device of the present invention faces the substrate, the heat generating element arranged on the upper surface of the substrate, the shield case arranged so as to surround the heat generating element and having an opening, and the upper surface of the substrate. A vapor chamber that directly or indirectly joins the heat generating element through the opening is provided, and the vapor chamber includes a housing, a working fluid sealed in the housing, and a wick arranged in the housing. A chamber main body portion including the above-mentioned chamber main body portion and a shield portion arranged in the above-mentioned housing are provided, and the said-mentioned shield portion is fitted with the above-mentioned shield case.

The vapor chamber of the present invention includes a housing, a working fluid sealed in the housing, a chamber main body portion having a wick arranged in the housing, and a shield portion arranged in the housing. The shield portion has a combining means.

According to the present invention, it is possible to provide an electronic device capable of relieving stress when the vapor chamber or the substrate is bent.

FIG. 1A is a cross-sectional view schematically showing an example of an electronic device according to the first embodiment of the present invention. FIG. 1B is a top view when the electronic device shown in FIG. 1A is cut along the cross-sectional line XX'. FIG. 2A is a cross-sectional view schematically showing an example of an electronic device according to a second embodiment of the present invention. FIG. 2B is a top view when the electronic device shown in FIG. 2A is cut along the cross-sectional line XX'. FIG. 3 is a cross-sectional view schematically showing an example of an electronic device according to a third embodiment of the present invention. FIG. 4A is a cross-sectional view schematically showing an example of an electronic device according to a fourth embodiment of the present invention. FIG. 4B is a cross-sectional view schematically showing another example of the electronic device according to the fourth embodiment of the present invention. FIG. 5A is a cross-sectional view schematically showing an example of an electronic device according to a fifth embodiment of the present invention. FIG. 5B is a cross-sectional view schematically showing another example of the electronic device according to the fifth embodiment of the present invention. FIG. 6A is a cross-sectional view schematically showing an example of an electronic device according to a sixth embodiment of the present invention. FIG. 6B is a top view when the electronic device shown in FIG. 6A is cut along the cross-sectional line XX'. FIG. 7 is a cross-sectional view schematically showing an example of an electronic device according to a seventh embodiment of the present invention. FIG. 8 is a cross-sectional view schematically showing an example of an electronic device according to an eighth embodiment of the present invention. FIG. 9 is a cross-sectional view schematically showing an example of an electronic device according to a comparative form. 10A and 10B are perspective views showing an example of the shape of the shield case. FIG. 11A is a perspective view showing an example of the shape of the first portion constituting the shield portion. FIG. 11B is a perspective view showing an example of the shape of the second portion constituting the shield portion. 12A and 12B are perspective views showing an example of a method for manufacturing a shield portion constituting the electronic device according to the sixth embodiment of the present invention.

Hereinafter, the electronic device and the vapor chamber of the present invention will be described.
However, the present invention is not limited to the following configurations, and can be appropriately modified and applied without changing the gist of the present invention. It should be noted that a combination of two or more individual desirable configurations of the present invention described below is also the present invention.

It goes without saying that each of the embodiments shown below is an example, and partial replacement or combination of the configurations shown in different embodiments is possible. In the second and subsequent embodiments, the description of the matters common to the first embodiment will be omitted, and only the differences will be described. In particular, the same action and effect due to the same configuration will not be mentioned sequentially for each embodiment.

In the following description, when each embodiment is not particularly distinguished, it is simply referred to as "the electronic device of the present invention" and "the vapor chamber of the present invention".

[First Embodiment]
FIG. 1A is a cross-sectional view schematically showing an example of an electronic device according to the first embodiment of the present invention. FIG. 1B is a top view when the electronic device shown in FIG. 1A is cut along the cross-sectional line XX'.
The electronic device 100 shown in FIGS. 1A and 1B is arranged so as to surround the substrate 110, the heat generating element 111 arranged on the upper surface 110a of the substrate 110, and the heat generating element 111, and has an opening 112b. It includes a shield case 112 and a vapor chamber 120 that faces the upper surface 110a of the substrate 110 and is joined to the heat generating element 111 by the heat conductive resin 113 via the opening 112b of the shield case 112. The vapor chamber 120 includes a chamber main body portion 123 and a shield portion 121, and the shield portion 121 is joined to the substrate 110 side of the housing 123a of the chamber main body portion 123 by a heat conductive bonding material 122. Further, the shield portion 121 is fitted with the shield case 112.

In the electronic device according to the first embodiment of the present invention, since the shield portion is fitted with the shield case, the stress when the vapor chamber or the substrate is bent can be effectively relieved.
Further, in the electronic device according to the first embodiment of the present invention, as shown in FIG. 1A, the heat generating element and the vapor chamber are joined via the opening of the shield case, and the shield portion and the shield Heat can be efficiently conducted by being combined with the case. This is because the heat generating element, which is a heat source, and the vapor chamber can be brought closer to each other. Further, the heat generating element and the vapor chamber can be joined without passing through the shield case, and the heat transferred from the lower part of the heat generating element to the substrate can be conducted to the vapor chamber through the shield case and the shield portion. be. For example, as in the electronic device 900 according to the comparative embodiment shown in FIG. 9, a copper plate 924 is attached to the vapor chamber 920 using a heat conductive bonding material 922, and the shield case 912 and the copper plate 924 arranged on the substrate 910 If the heat conductive resin 925 is arranged between the heat conductive resin 925 and the heat conductive resin 913 is sandwiched between the shield case 912 and the heat generating element 911, the shield case 912 is placed between the heat generating element 911 and the vapor chamber 920. In addition, since the two surfaces between the heat generating element 911 and the shield case 912 and the shield case 912 and the vapor chamber 920 are joined by the heat conductive resins 913 and 925, heat is efficiently generated. Cannot spread.
Further, in the electronic device according to the first embodiment of the present invention, the vapor chamber also functions as the top surface of the shield case and is excellent in shielding property.

In the form shown in FIG. 1A, the shield portion 121 has a first portion 121a extending in the thickness direction T of the vapor chamber and a second portion 121b extending in the surface direction S of the vapor chamber, and also has a hole in the shield portion 121. The 121c and the protrusion 112a of the shield case 112 are combined. Further, as shown in FIG. 1A, it is preferable that at least a part of the outer surface 112d of the shield case 112 is covered by at least a part of the inner surface 121e of the shield portion.
Hereinafter, when the term "thickness direction" is used in the present specification without particular notice, it means the vapor chamber thickness direction. Further, when the term "plane direction" is used, it means the vapor chamber surface direction.

In the electronic device according to the first embodiment of the present invention, the shield portion is integrated with the shield case. The shield portion preferably has a matching means such as a hole, a recess, or a protrusion. The size of the combining means is not particularly limited, and may be appropriately set depending on the size of the electronic device, the shield portion, and the like.
Among them, in the electronic device according to the first embodiment of the present invention, the shield portion has a hole or a recess, and the protrusion of the shield case and the hole or the recess are combined, or the shield portion has a hole or a recess. It is preferable that the shield case has a protrusion and the hole or recess of the shield case is aligned with the protrusion.
The number of combining means included in the shield portion is not limited to one or two or more. For example, the shield portion forms a continuous frame with the surface direction as the circumferential direction, and the frame is viewed from above. When the shape at the time is a quadrangle, it is preferable that each side of the quadrangle has one or more merging means, and the shield portion preferably has four or more merging means.

In the electronic device according to the first embodiment of the present invention, the shield portion preferably has a first portion extending in the thickness direction of the vapor chamber. The shield portion may be composed of only the first portion, or may be composed of a first portion and other portions such as a second portion and a third portion described later.

The first portion may have a certain angle with respect to the thickness direction, not only when it is completely parallel to the thickness direction, and has an angle of 30 ° or less with respect to the thickness direction, for example. You may be. The first portion preferably has an angle of 15 ° or less with respect to the thickness direction, more preferably an angle of 10 ° or less, and an angle of 5 ° or less. It is more preferable, and it is particularly preferable to have an angle of 1 ° or less.

Since the shield portion is intended to be fitted to the shield case, the first portion has the surface direction as the circumferential direction so as to be in contact with the outer surface of the shield case and surround the outer surface of the shield case. It is preferable to form a continuous frame (see FIG. 11A). The frame formed by the first portion is not limited to a circular shape or a square shape when viewed from the vapor chamber side. For example, it may be appropriately determined according to the shape of the shield case.

The length of the first portion in the thickness direction T (for example, 1021al in FIG. 11A) may be appropriately set depending on the type and size of the electronic device, but may be, for example, 0.10 mm or more and 50 mm or less. It may be 0.0 mm or more and 10 mm or less.

The thickness of the first portion in the plane direction S (for example, 1021 at in FIG. 11A) may be appropriately set, and may be, for example, 0.01 mm or more and 10 mm or less, and 0.10 mm or more and 1.0 mm or less. good.

In addition, in this specification, a "frame" means a shape which is continuous in a circumferential direction and has an annular shape, or a shape which has a defect portion in a part of the circumferential direction in the shape. The defect portion is preferably 25% or less, more preferably 20% or less, further preferably 15% or less, and particularly preferably 10% or less of the length in the circumferential direction.

In the electronic device according to the first embodiment of the present invention, in addition to the first portion, the shield portion extends from the vapor chamber side (for example, the upper side of FIG. 1) of the first portion in the direction of the vapor chamber surface. It is preferable to have two sites. The second portion is preferably connected to the chamber body.

The second portion may have a certain angle with respect to the plane direction, not only when it is completely parallel to the plane direction, and has an angle of 30 ° or less with respect to the plane direction, for example. You may be. The second portion preferably has an angle of 15 ° or less with respect to the surface direction, more preferably an angle of 10 ° or less, and an angle of 5 ° or less. It is more preferable, and it is particularly preferable to have an angle of 1 ° or less.

The second site preferably forms a frame, as shown in FIG. 11B.

The length of the second portion in the plane direction S (for example, 1021 bl in FIG. 11B) may be appropriately set depending on the type and size of the electronic device, but may be, for example, 0.10 mm or more and 100 mm or less. It may be 0.0 mm or more and 10 mm or less.

The thickness of the second portion in the thickness direction T (1021 bt in FIG. 11B) may be appropriately set, and may be, for example, 0.01 mm or more and 10 mm or less, and 0.10 mm or more and 1.0 mm or less.

As shown in FIG. 1A, the shield portion preferably has a first portion extending in the thickness direction and a second portion extending from the vapor chamber side of the first portion in the vapor chamber surface direction, preferably in the thickness direction. A first portion that extends inward and forms a continuous frame with the surface direction as the circumferential direction, and extends from the vapor chamber side of the first portion toward the inside of the frame formed by the first portion, and goes around the surface direction. It is more preferable to have the second portion forming a continuous frame as a direction.

In the electronic device of the present invention, as shown in FIG. 1A, the shield portion has a first portion extending in the thickness direction of the vapor chamber, and has a hole penetrating in the vapor chamber surface direction or a recess recessed in the vapor chamber surface direction. It is preferable that the shield case has a protrusion in the first portion and projects in the surface direction, and the protrusion and the hole or the recess are combined. As described above, the shield portion has the hole or the recess, and the shield case has the protrusion, so that the shield case and the shield portion can be combined with each other.
However, in the electronic device of the present invention, it is sufficient that the shield portion and the shield case are combined, and the combining means is not limited to the above. For example, there is also a form in which the shield portion has a protrusion, the shield case has a hole or a recess, and the protrusion of the shield portion and the hole or the recess of the shield case are combined. Further, the combining means may be any means that can combine the shield portion and the shield case, and various combining means can be adopted. It is preferable that the shield portion is fitted so as to surround the outer surface of the shield case, but the shield case may be joined so as to surround the outer surface of the shield portion.

In the electronic device of the present invention, the shield portion may be formed integrally with the chamber main body portion or may be formed separately from the chamber main body portion, but from the viewpoint of productivity, FIG. 1A It is preferable that they are formed separately as shown by.

When the shield portion and the chamber main body portion are formed separately, it is preferable that the shield portion is joined to the chamber main body portion with a heat conductive bonding material as shown in FIG. 1A. The heat conductive bonding material preferably has a thermal conductivity of 10 W / mK or more, more preferably 50 W / mK or more, and further preferably 100 W / mK or more.
The thermally conductive bonding material is preferably a material having a low elastic modulus, for example, the elastic modulus is preferably 50 GPa or less, and more preferably 1 GPa or less. By using a thermally conductive bonding material having a low elastic modulus, the stress at the time of bending can be relieved more efficiently.
Specifically, as the heat conductive bonding material, a solder, a filler-containing adhesive, or a brazing material is preferable, and a solder or a filler-containing adhesive is particularly preferable.
When the shield portion and the chamber main body portion are integrally formed, a heat conductive bonding material for joining the shield portion and the chamber main body portion is unnecessary.

The shield portion is not particularly limited as long as it is made of a material capable of shielding electromagnetic waves, but is preferably made of a metal and preferably made of a metal having a high thermal conductivity. Specifically, a metal having a thermal conductivity of 10 W / mK or more is preferable, a metal having a thermal conductivity of 50 W / mK or more is more preferable, and a metal having a thermal conductivity of 100 W / mK or more is further preferable. By using a metal, particularly a metal having a high thermal conductivity, as described above, heat can be conducted more efficiently.
The metal constituting the shield portion preferably has a high tensile strength, and preferably a metal having a tensile strength higher than 300 MPa. By using a metal having a high tensile strength as described above, the stress at the time of bending can be effectively relieved.
As the metal constituting the shield portion, copper, aluminum, stainless steel, titanium or an alloy thereof is preferable, aluminum, copper or a copper alloy is more preferable, and copper or a copper alloy is further preferable. Examples of the copper alloy include, but are not limited to, phosphor bronze, Corson copper, titanium copper, nickel silver and the like.

The shield case is arranged so as to surround the periphery of the heat generating element and has an opening. The shield case is preferably joined or embedded in the upper surface of the substrate.
The shield case has a side wall portion extending in the thickness direction, and it is preferable that the substrate side (lower side of FIG. 1A) of the side wall portion is joined or embedded in the substrate. Further, the side wall portion of the shield case preferably forms a continuous frame with the surface direction as the circumferential direction, and more preferably has a shape that surrounds the side surface of the heat generating element by the side wall portion. In the shield case, as shown in FIG. 1A, it is preferable that the outer surface of the frame formed by the side wall portion and the inner surface of the frame of the first portion formed by the shield portion are in contact with each other.
It is also preferable that the shield case has a top surface portion (for example, 112f in FIG. 1A) on the vapor chamber side (upper side of FIG. 1A) of the side wall portion, and the opening portion is formed in the top surface portion. The top surface portion is preferably a portion extending in the surface direction.

The shape of the opening of the shield case is not limited, as long as the heat generating element and the vapor chamber can be joined through the opening. For example, when the electronic device of the present invention is viewed from the upper surface side of the substrate, it may be square (see FIG. 10A) or circular (see FIG. 10B). The shield case may have a plurality of openings, but usually there is only one opening for joining the vapor chamber and the heat generating element.
It is preferable that the opening is formed so that the entire heat generating element can be seen from the opening when viewed from the upper surface side of the substrate.
In the electronic device of the present invention, the heat generated from the heat generating element can be efficiently diffused by joining the vapor chamber and the heat generating element through the opening.

The shield case and the shield portion are combined. The shield case preferably has holes, recesses, protrusions, and other means of fitting.
Among them, in the electronic device of the present invention, the shield case has a protrusion, and the protrusion and the hole or recess of the shield portion are combined, or the shield case has a hole or recess. , It is preferable that the hole or the recess and the protrusion of the shield portion described above are combined. The size of the above-mentioned combining means is not particularly limited, and may be appropriately set according to the size of the electronic device, the shield case, or the like.
Among them, in the electronic device according to the first embodiment of the present invention, the shield portion has a hole or a recess, and the protrusion of the shield case and the hole or the recess are combined, or the shield portion has a hole or a recess. It is preferable that the shield case has a protrusion and the hole or recess of the shield case is aligned with the protrusion.
The number of combining means included in the shield case is not limited to one or two or more. For example, the shield case forms a continuous frame with the surface direction as the circumferential direction, and the frame is viewed from above. When the shape at the time is a quadrangle, it is preferable that each side of the quadrangle has one or more merging means, and the shield case preferably has four or more merging means.

The shield case is not particularly limited as long as it is made of a material capable of shielding electromagnetic waves, but is preferably made of metal. Examples of the metal constituting the shield case include stainless steel, copper, aluminum, magnesium and the like, but stainless steel or copper is particularly preferable, and copper is more preferable. The type of stainless steel is not limited, and various types of stainless steel can be used.

The heat conductive resin is not limited as long as it is a resin material having heat conductivity.
In FIG. 1A, the heat generating element 111 is indirectly bonded to the vapor chamber via the heat conductive resin 113, but in the first embodiment of the present invention, the heat generating element and the vapor chamber are directly bonded. In that case, a heat conductive resin is not required.

In the electronic device shown in FIG. 1A, the chamber main body 123 is a housing 123a, a working fluid (not shown) sealed in the housing 123a, and a wick arranged in the housing 123a (FIG. Not shown). In the first embodiment, the vapor chamber main body is not limited as long as it has the above configuration, and a conventionally known vapor chamber structure can be used, and a conventionally known vapor chamber structure can be appropriately used. It can be transformed and used.

In the chamber main body, the configuration of the housing is not particularly limited, but for example, it may be composed of the first sheet and the second sheet facing each other to which the outer edges are joined, and usually, steam composed of cavities. A flow path is provided. The arrangement of the working fluid and the wick is not limited as long as it is arranged so as to function as a vapor chamber, but the wick is arranged on the inner wall surface of at least one of the first sheet and the second sheet. Is preferable. It is preferable that one or more columns are arranged between the first sheet and the second sheet.

The shape of the housing is not particularly limited. For example, the planar shape of the housing (the shape seen from the upper side of the drawing in FIG. 1A) includes polygons such as squares and triangles, circles, ellipses, and combinations thereof.

The first sheet and the second sheet constituting the housing may be overlapped so that their ends coincide with each other, or the ends may be displaced and overlapped.

The materials constituting the first sheet and the second sheet are not particularly limited as long as they have properties suitable for use as a vapor chamber, such as thermal conductivity, strength, and flexibility. The material constituting the first sheet and the second sheet is preferably a metal, and examples thereof include copper, nickel, aluminum, magnesium, titanium, iron, and the like, or alloys containing them as main components. The material constituting the first sheet and the second sheet is particularly preferably copper or a copper alloy.

The material constituting the first sheet and the material constituting the second sheet may be different. For example, by using a high-strength material for the first sheet, the stress applied to the housing can be dispersed. Further, by using different materials, one sheet can obtain one function and the other sheet can obtain another function. The above functions are not particularly limited, and examples thereof include a heat conduction function and an electromagnetic wave shielding function.

The thickness of the first sheet and the second sheet is not particularly limited, but if the first sheet and the second sheet are too thin, the strength of the housing is lowered and deformation is likely to occur. Therefore, the thickness of the first sheet and the second sheet is preferably 20 μm or more, and more preferably 30 μm or more. On the other hand, if the first sheet and the second sheet are too thick, it becomes difficult to reduce the thickness of the entire vapor chamber. Therefore, the thickness of the first sheet and the second sheet is preferably 200 μm or less, more preferably 150 μm or less, and further preferably 100 μm or less. The thicknesses of the first sheet and the second sheet may be the same or different.

In the chamber main body portion, the thickness of the first sheet may be constant, or a thick portion and a thin portion may be present. Similarly, the thickness of the second sheet may be constant, or there may be a thick portion and a thin portion. Further, the second sheet of the portion not in contact with the support column may be recessed inside the housing.

The support column supports the first sheet and the second sheet from the inside. By arranging the columns inside the housing, it is possible to prevent the housing from being deformed when the inside of the housing is decompressed or when an external pressure from the outside of the housing is applied. The support column may be directly in contact with the first sheet or the second sheet and may be supported, or may be supported via another member such as a wick. Further, the support column may be integrated with the first sheet or the second sheet, and may be formed by, for example, etching the inner wall surface of the first sheet or the second sheet.

The shape of the support column is not particularly limited, and examples thereof include a cylindrical shape, a prismatic shape, a truncated cone shape, and a truncated cone shape.

The arrangement of the columns is not particularly limited, but is preferably evenly arranged, for example, in a grid pattern so that the distance between the columns is constant. By arranging the columns evenly, uniform strength can be ensured over the entire vapor chamber.

The working liquid is not particularly limited as long as it can cause a gas-liquid phase change in the environment inside the housing, and for example, water, alcohols, CFC substitutes, or the like can be used. The working fluid is preferably an aqueous compound, more preferably water.

The wick is not particularly limited as long as it has a capillary structure capable of moving the hydraulic fluid by capillary force. The wick's capillary structure may be a known structure used in conventional vapor chambers. Examples of the capillary structure include fine structures having irregularities such as pores, grooves, and protrusions, such as a porous structure, a fiber structure, a groove structure, and a mesh structure. These capillary structures form a liquid flow path.

The material of the wick is not particularly limited, and for example, a metal porous film formed by etching or metal processing, a mesh, a non-woven fabric, a sintered body, a porous body, or the like is used. The mesh used as the material of the wick may be composed of, for example, a metal mesh, a resin mesh, or a surface-coated mesh thereof, and is preferably composed of a copper mesh, a stainless (SUS) mesh, or a polyester mesh. .. The sintered body used as the material of the wick may be composed of, for example, a metal porous sintered body and a ceramic porous sintered body, and is preferably composed of a copper or nickel porous sintered body. .. The porous body used as the material of the wick may be, for example, a porous body composed of a metal porous body, a ceramic porous body, a resin porous body, or the like.

The method for manufacturing the chamber body is not particularly limited as long as the above configuration can be obtained. For example, the first sheet on which the wick is arranged and the second sheet on which the support columns are arranged are overlapped and joined, leaving an opening for encapsulating the hydraulic fluid, and the hydraulic fluid is put into the housing through the opening, and then the hydraulic fluid is put into the housing. It can be obtained by sealing the opening.

The method of joining the first sheet and the second sheet is not particularly limited, but for example, laser welding, resistance welding, diffusion welding, brazing, TIG welding (tungsten-inert gas welding), ultrasonic bonding, resin sealing, etc. Can be mentioned. Of these, laser welding, resistance welding or brazing is preferred.

The chamber main body portion and the shield portion may be formed integrally or separately, but when they are integrally formed, the first sheet having the portion to be the shield portion and the first sheet A vapor chamber can be obtained by joining the two sheets. When it is formed as a separate body, a vapor chamber can be obtained by forming the chamber main body portion and then joining the shield portion with the above-mentioned heat conductive bonding material.

The heat generating element is arranged on the upper surface of the substrate. The heat generating element is not limited as long as it is an element that generates heat when operated, and examples thereof include a processor, an LED, a power amplifier, and a camera module.

The substrate is not particularly limited, and may be a flexible substrate or a rigid substrate. The substrate may be, for example, a printed circuit board made of a flat substrate such as a glass epoxy substrate, a ceramic substrate, or a paper phenol substrate. The substrate may be a multilayer wiring board, and may be composed of a double-sided substrate, a multilayer substrate, a build-up substrate, or the like, but is not particularly limited.

The electronic device of the present invention is not limited, and examples thereof include smartphones, tablet terminals, notebook computers, game devices, wearable devices, and in-vehicle devices.

[Second Embodiment]
In the electronic device according to the second embodiment of the present invention, the first portion forms a continuous frame with the surface direction as the circumferential direction, and the second portion forms the top surface of the frame formed by the first portion. The shield portion is formed so as to cover the opening of the shield case.

FIG. 2A is a cross-sectional view schematically showing an example of an electronic device according to a second embodiment of the present invention. FIG. 2B is a top view when the electronic device shown in FIG. 2A is cut along the cross-sectional line XX'.
In the electronic device 200 shown in FIGS. 2A and 2B, the shield portion 221 extends in the thickness direction T and extends in the plane direction S with the first portion 221a forming a continuous frame with the plane direction S as the circumferential direction. It has a second portion 221b that forms the top surface 221e of the frame formed by the one portion 221a. In the electronic device 200, the first portion 221a forming the frame is arranged around the second portion 221b on a flat surface, a recess is formed by the first portion 221a and the second portion 221b, and the recess is the outer periphery of the shield case 212. It is arranged so as to cover. The shield portion 221 can function as the top surface of the shield case 212 by covering the opening of the shield case 212.

[Third Embodiment]
In the electronic device according to the third embodiment of the present invention, the shield portion has a laminated structure including two or more metal layers. The laminated structure more preferably includes a first metal layer of copper, a copper alloy or aluminum, and a second metal layer of stainless steel or nickel.

FIG. 3 is a cross-sectional view schematically showing an example of an electronic device according to a third embodiment of the present invention.
In the electronic device 300 shown in FIG. 3, the shield portion 321 has a laminated structure composed of the first metal layer 321A and the second metal layer 321B.

As shown in FIG. 3, when the first metal layer is arranged on the shield case side and the second metal layer is arranged on the opposite side of the shield case, the first metal layer is a layer of copper, copper alloy or aluminum. The second metal layer is preferably a stainless steel or nickel layer. With such a form, the strength and thermal conductivity of the shield portion can be improved. Specific examples thereof include a form in which the first metal layer / second metal layer is copper / stainless steel, copper alloy / stainless steel, copper / nickel, or the like.

When the shield portion has a two-layer structure as shown in FIG. 3, the thickness of the first metal layer may be 0.01 mm or more and 5.0 mm or less, and the thickness of the second metal layer is 0.01 mm or more and 5.0 mm. It may be:

In FIG. 3, the shield portion has a two-layer structure, but the shield portion in the third embodiment may be composed of three or more metal layers. The number of layers is not limited, but from the viewpoint of productivity, it is preferably 10 layers or less, more preferably 5 layers or less, and further preferably 3 layers or less.

The laminated structure can be produced by laminating a metal plate constituting the first metal layer and a metal plate constituting the second metal layer, or plating the metal plate.

[Fourth Embodiment]
In the electronic device according to the fourth embodiment of the present invention, the first portion extends in the thickness direction of the vapor chamber, forms a continuous frame with the surface direction of the vapor chamber as the circumferential direction, and curves in the outer direction of the frame.

FIG. 4A is a cross-sectional view schematically showing an example of an electronic device according to a fourth embodiment of the present invention.
In the electronic device 400 shown in FIG. 4A, the first portion 421a of the shield portion 421 is formed in a frame shape, and has a curved portion 421d that curves in the outward direction of the frame. The curved portion preferably exists at the tip opposite to the vapor chamber of the first portion. With such a form, stress can be effectively relieved when the vapor chamber or the substrate is bent.

In the electronic device according to the fourth embodiment of the present invention, the tip of the shield case on the vapor chamber side may be curved toward the heat generating element side.

FIG. 4B is a cross-sectional view schematically showing another example of the electronic device according to the fourth embodiment of the present invention.
In the electronic device 400'shown in FIG. 4B, the tip 412c of the shield case 412 on the vapor chamber 420 side is curved toward the heat generating element 411. Even with such a form, stress can be effectively relieved when the vapor chamber or the substrate is bent.

[Fifth Embodiment]
In the electronic device according to the fifth embodiment of the present invention, the shield portion has a first portion extending in the thickness direction of the vapor chamber, and has a hole penetrating in the vapor chamber surface direction or a recess recessed in the vapor chamber surface direction. The shield case has a protrusion that protrudes in the surface direction, and the protrusion and the hole or recess are combined with each other, and a gap is provided between the protrusion and the hole or recess. ..

FIG. 5A is a cross-sectional view schematically showing an example of an electronic device according to a fifth embodiment of the present invention.
In the electronic device 500 shown in FIG. 5A, a hole 521c penetrating in the surface direction is formed in the first portion 521a of the shield portion 521, and the shield case 512 has a protrusion 512a protruding in the surface direction. , The protrusion 512a and the hole 521c of the shield portion are combined. Further, there is a gap 521d between the protrusion 512a and the hole 521c. With such a form, stress can be effectively relieved when the vapor chamber or the substrate is bent.

In the electronic device according to the fifth embodiment of the present invention, it is also preferable to have a resin in the gap.

FIG. 5B is a cross-sectional view schematically showing another example of the electronic device according to the fifth embodiment of the present invention.
In the electronic device 500'shown in FIG. 5B, the resin 521e is provided in the gap 521d between the hole 521c and the protrusion 512a. With such a form, stress can be relieved more effectively when the vapor chamber or the substrate is bent.

The resin is not particularly limited, but a highly flexible resin is preferable, and examples thereof include silicon, epoxy, and urethane.

[Sixth Embodiment]
In the electronic device according to the sixth embodiment of the present invention, the first portion extends in the thickness direction and forms a continuous frame with the plane direction as the circumferential direction, and the second portion is the vapor chamber of the first portion. A frame that extends from the side toward the inside of the frame formed by the first portion and is continuous with the plane direction as the circumferential direction is formed, and the shield portion further extends from the inner peripheral portion of the frame formed by the second portion. It has a third portion extending in the thickness direction, and the third portion is in contact with the side surface of the heat generating element.

FIG. 6A is a cross-sectional view schematically showing an example of an electronic device according to a sixth embodiment of the present invention. FIG. 6B is a top view when the electronic device shown in FIG. 6A is cut along the cross-sectional line XX'.
In the electronic device 600 shown in FIGS. 6A and 6B, the shield portion 621 extends in the thickness direction and forms a continuous frame with the plane direction as the circumferential direction. Of the second part 621b extending from the upper side of 6A) to the inside of the frame formed by the surface direction and the first part 621a to form a continuous frame with the surface direction as the circumferential direction, and the frame formed by the second part 621b. It has a third portion 621d extending from the peripheral portion in the thickness direction. By arranging the third portion 621d so as to be in contact with the side surface 611a of the heat generating element 611, heat can be efficiently conducted from the heat generating element 611 to the vapor chamber 620.

The third portion may have a certain angle with respect to the thickness direction, not only when it is completely parallel to the thickness direction, and has an angle of 30 ° or less with respect to the thickness direction, for example. You may be. The third portion preferably has an angle of 15 ° or less with respect to the thickness direction, more preferably an angle of 10 ° or less, and an angle of 5 ° or less. It is more preferable, and it is particularly preferable to have an angle of 1 ° or less.

The third portion in contact with the side surface of the heat generating element may be curved or bent. The shield portion may have one or more third portions, and when it has a plurality of third portions, at least one third portion may be in contact with the side surface of the heat generating element. Of course, it is also possible to hold the heat generating element at a plurality of third parts.

The method for manufacturing the shield portion constituting the electronic device according to the sixth embodiment of the present invention is not particularly limited, but for example, a notch is made in the lines P1 and P2 on the top surface of the lid-shaped shield portion shown in FIG. 12A. By bending along the lines Q1 and Q2, a shield portion having a shape as shown in FIG. 12B can be easily manufactured.

[7th Embodiment]
In the electronic device according to the seventh embodiment of the present invention, the chamber main body portion has one or more convex portions on the substrate side, and the shield portion is arranged on at least one of the convex portions. In the seventh embodiment, since the chamber main body has a convex portion, the hollow region inside the housing can be expanded, so that the heat diffusion ability is excellent.

FIG. 7 is a cross-sectional view schematically showing an example of an electronic device according to a seventh embodiment of the present invention.
In the electronic device 700 shown in FIG. 7, the chamber main body portion 723 has a convex portion 723b, and the shield portion 721 is arranged on the convex portion. In FIG. 7, the shield portion 721 is composed of only the first portion extending in the thickness direction, but the shape of the shield portion in the seventh embodiment is not limited, and the shape illustrated in the first to sixth embodiments described above is used. In addition, a shape modified as appropriate can be adopted. For example, it may have a second portion extending in the plane direction from the vapor chamber side (upper side of FIG. 7) of the first portion, or may have the third portion described above.
Further, in the vapor chamber 720 of FIG. 7, the shield portion 721 is arranged as a separate body on the convex portion 723b of the chamber main body portion 723, and the convex portion 723b and the shield portion 721 are joined by the heat conductive bonding material 722. , The shield portion 721 may be integrally formed with the chamber main body portion 723.

In the seventh embodiment of the present invention, the convex portion is formed integrally with the chamber main body portion. The number of the convex portions may be one, or two or more. For example, the number may be 8 or less, or 4 or less. From the viewpoint of productivity, it is preferable that the number of convex portions is one, and it is preferable that all the shield portions are arranged on one convex portion.
The height of the convex portion is not particularly limited and may be appropriately set depending on the type of electronic device or the like, but may be, for example, 0.01 mm or more and 1.0 mm or less.

[8th Embodiment]
In the electronic device according to the eighth embodiment of the present invention, the chamber main body is composed of a housing composed of facing first and second sheets to which outer edges are joined, and a working fluid sealed in the housing. And the wick arranged on the inner wall surface of at least one of the first sheet and the second sheet, and the first sheet and the second sheet so as to support the first sheet and the second sheet from the inside. It is provided with a support column arranged between the seat and the seat. With the above configuration, heat can be conducted more efficiently.

FIG. 8 is a cross-sectional view schematically showing an example of an electronic device according to an eighth embodiment of the present invention.
In the electronic device 800 shown in FIG. 8, the chamber main body 823 includes a housing 823c composed of a first sheet 823a and a second sheet 823b facing each other, a working fluid 823d sealed in the housing 823c, and a first. It is provided with a wick 823e arranged on the inner wall surface of the sheet 823a. The first sheet 823a and the second sheet 823b are joined to each other at the outer edge 823f and sealed. Further, a plurality of columns 823g are arranged between the first sheet 823a and the second sheet 823b so as to support the first sheet 823a and the second sheet 823b from the inside.

Inside the housing 823c, a steam flow path 823h formed of a cavity is provided. The steam flow path 823h is a flow path for moving the hydraulic fluid 823d of the gas phase, and communicates with the plane of the housing 823c. In FIG. 8, the cavity between the inner wall surface of the second sheet 823b and the wick 823e constitutes the steam flow path 823h. In order to secure the steam flow path 823h, the first sheet 823a and the second sheet 823b are supported by the columns 823g.

Further, the wicks arranged on the inner wall surface of the first sheet do not necessarily have to be arranged over the entire inner wall surface of the first sheet, and may be partially arranged.

[Other Embodiments]
The electronic device of the present invention is not limited to the above embodiment, and various applications and modifications can be added within the scope of the present invention with respect to the configuration, manufacturing conditions, and the like of the electronic device.

The vapor chamber constituting the electronic device of the present invention is also one of the present inventions. That is, the vapor chamber of the present invention includes a housing, a working fluid sealed in the housing, a chamber main body portion having a wick arranged in the housing, and a shield portion arranged in the housing. The shield portion is provided with a combining means. By having the above-mentioned configuration, the vapor chamber of the present invention can effectively diffuse the heat of the electronic device by arranging the shield case on the substrate on which the heat generating element is arranged and the shield portion. ..

The combination means is not particularly limited, and conventionally known combination means can be adopted. For example, when the mating material has a protrusion, it may be a hole or a recess, and when the mating material has a hole or a recess, it may be a protrusion.

The vapor chamber of the present invention can take the same embodiment as the vapor chamber constituting the electronic device of the present invention described above.

For example, the shield portion preferably has a first portion extending in the thickness direction of the vapor chamber.

It is preferable that the shield portion has a first portion extending in the thickness direction of the vapor chamber, and the first portion has a hole penetrating in the vapor chamber surface direction or a recess recessed in the vapor chamber surface direction.

It is preferable that the first portion forms a continuous frame with the vapor chamber surface direction as the circumferential direction and is curved in the outer direction of the frame.

The shield portion may be formed integrally with the chamber main body portion, or may be formed separately from the chamber main body portion.

The shield portion preferably has a first portion extending in the thickness direction of the vapor chamber and a second portion extending from the vapor chamber side of the first portion in the vapor chamber surface direction, and is extending in the thickness direction and having a surface. A first portion forming a continuous frame with the direction as the circumferential direction and a frame extending from the vapor chamber side of the first portion toward the inside of the frame formed by the first portion and continuing with the plane direction as the circumferential direction. It is more preferable to have a second site to be formed.

The first part forms a continuous frame with the vapor chamber surface direction as the circumferential direction, and the second part is from the vapor chamber side of the first part to the vapor chamber surface direction and the inside of the frame formed by the first part. A frame extending in the direction and continuous with the surface direction as the circumferential direction is formed, and the shield portion further has a third portion extending in the vapor chamber thickness direction from the inner peripheral portion of the frame formed by the second portion. However, it is preferable that the third portion is in contact with the side surface of the heat generating element.

The first part forms a continuous frame with the surface direction as the circumferential direction, and the second part extends from the vapor chamber side of the first part toward the vapor chamber surface direction, and the frame formed by the first part. It is preferable to form the top surface of the.

The shield portion preferably has a laminated structure including two or more metal layers, and the laminated structure includes a first metal layer of copper, a copper alloy or aluminum, and a second metal layer of stainless steel or nickel. Is preferable.

The shield portion is preferably bonded to the chamber main body portion with a heat conductive bonding material, and the heat conductive bonding material is preferably solder, a filler-containing adhesive, or a brazing material.

It is preferable that the chamber main body portion has one or more convex portions on the substrate side, and the shield portion is arranged on at least one of the convex portions.

The chamber main body includes a housing composed of facing first and second sheets to which outer edges are joined, a working fluid sealed in the housing, and the first sheet and the second sheet. A wick arranged on the inner wall surface of at least one sheet, and a support column arranged between the first sheet and the second sheet so as to support the first sheet and the second sheet from the inside. Is preferable.

The electronic device and vapor chamber of the present invention can be used in a wide range of applications in fields such as personal digital assistants. For example, it can be used to lower the temperature of a heat source such as a CPU and extend the usage time of an electronic device, and can be used for smartphones, tablets, notebook PCs, and the like.

100, 200, 300, 400, 400', 500, 500', 600, 700, 800, 900 Electronic equipment 1021al Length of the first part of the shield part 1021at Thickness of the first part of the shield part 1021bl Second part of the shield part Part length 1021bt Thickness of the second part of the shield part 110, 210, 310, 410, 510, 610, 710, 810, 910 Board 110a Top surface of the board 111, 211, 311, 411, 511, 611, 711, 811 , 911 Heat generating elements 112, 212, 312, 412, 512, 612, 712, 812, 912 Shield case 112a, 512a Shield case protrusion 112b Shield case opening 112d Shield case outer surface 112e Shield case side wall 112f Shield case Top surface part 113, 213, 313, 413, 513, 613, 713, 813, 913, 925 Thermal conductive resin 120, 220, 320, 420, 520, 620, 720, 820, 920 Vapor chamber 121, 221 and 321 , 421, 521, 621, 721, 821 Shielded parts 121a, 221a, 421a, 521a, 621a, 1021a First part of the shield part 121b, 221b, 521b, 621b, 1021b Second part of the shield part 121c, 221c, 521c, 621c Hole in the shield part 121e Inner surface of the shield part 122, 222, 322, 422, 522, 622, 722, 822, 922 Thermal conductive bonding material 123, 223, 323, 423, 523, 623, 723, 823 Chamber body 123a, 823c Chamber 221e Top surface 321A First metal layer 321B Second metal layer 412c Shield case tip 421d Curved part 521d Gap 521e Resin 611a Side surface 621d Shield part third part 723b Convex part 823a First sheet 823b Second sheet 823d Hydraulic fluid 823e Wick 823f Outer edge 823g Strut 823h Steam flow path 924 Copper plate P1, P2, Q1, Q2 Line T Vapor chamber thickness direction S Vapor chamber surface direction

Claims (18)

With the board
The heat generating element arranged on the upper surface of the substrate and
A shield case arranged so as to surround the heat generating element and having an opening, and a shield case.
A vapor chamber facing the upper surface of the substrate and directly or indirectly joining the heat generating element via the opening is provided.
The vapor chamber includes a housing, a working fluid sealed in the housing, a chamber main body portion having a wick arranged in the housing, and a shield portion arranged in the housing.
An electronic device in which the shield portion and the shield case are combined. The electronic device according to claim 1, wherein the shield portion has a first portion extending in the thickness direction of the vapor chamber. The shield portion has a hole penetrating in the direction of the vapor chamber surface or a recess recessed in the direction of the vapor chamber surface in the first portion.
The shield case has a protrusion protruding in the surface direction, and has a protrusion.
The electronic device according to claim 2, wherein the protrusion and the hole or the recess are combined. The electronic device according to claim 3, wherein a gap is provided between the protrusion and the hole or the recess. The electronic device according to claim 4, which has a resin in the gap. The electronic device according to any one of claims 2 to 5, wherein the first portion forms a continuous frame with the vapor chamber surface direction as the circumferential direction, and is curved in the outer direction of the frame. The electronic device according to any one of claims 1 to 6, wherein the shield portion is formed integrally with the chamber main body portion. The electronic device according to any one of claims 1 to 6, wherein the shield portion is formed separately from the chamber main body portion. The shield portion
The first part that extends in the thickness direction of the vapor chamber,
The electronic device according to claim 8, further comprising a second portion extending from the vapor chamber side of the first portion toward the surface of the vapor chamber. The first portion forms a continuous frame with the vapor chamber surface direction as the circumferential direction.
The second portion extends from the vapor chamber side of the first portion toward the inside of the frame formed by the first portion, and forms a continuous frame with the surface direction as the circumferential direction.
The shield portion further has a third portion extending in the thickness direction of the vapor chamber from the inner peripheral portion of the frame formed by the second portion.
The electronic device according to claim 9, wherein the third portion is in contact with a side surface of the heat generating element. The first portion forms a continuous frame with the surface direction as the circumferential direction.
The second part forms the top surface of the frame formed by the first part.
The electronic device according to claim 9, wherein the shield portion is arranged so as to cover an opening portion of the shield case. The electronic device according to any one of claims 8 to 11, wherein the shield portion has a laminated structure including two or more metal layers. The electronic device according to claim 12, wherein the laminated structure includes a first metal layer of copper, a copper alloy or aluminum, and a second metal layer of stainless steel or nickel. The electronic device according to any one of claims 8 to 13, wherein the shield portion is joined to the chamber main body portion with a heat conductive bonding material. The electronic device according to claim 14, wherein the thermally conductive bonding material is a solder, a filler-containing adhesive, or a brazing material. The electronic device according to any one of claims 1 to 15, wherein the chamber main body portion has one or more convex portions on the substrate side, and the shield portion is arranged on at least one of the convex portions. The chamber body is
A housing composed of opposing first and second sheets with outer edges joined,
The working fluid enclosed in the housing and
A wick arranged on the inner wall surface of at least one of the first sheet and the second sheet,
A strut arranged between the first sheet and the second sheet so as to support the first sheet and the second sheet from the inside,
The electronic device according to any one of claims 1 to 16. A chamber, a chamber main body including a housing, a hydraulic fluid sealed in the housing, and a wick arranged in the housing,
A shield portion arranged in the housing is provided.
The shield portion is a vapor chamber having a combining means.

Images