JP2006526128A - Thin plate type cooling device that prevents dryout - Google Patents

Abstract

The present invention provides a thin plate type cooling device including at least one cavity formed in an inner wall of a refrigerant circulation loop in order to remove a dry-out phenomenon of the refrigerant.

Description

  The present invention relates to a thin plate type cooling device for cooling heat such as a semiconductor integrated circuit device, and more particularly, to a cooling device using a cooling method by phase change of a working fluid, and can prevent a dry-out phenomenon of a refrigerant. The present invention relates to a thin plate type cooling device.

  As the design rules decrease due to the trend toward higher integration of semiconductor elements, the number of transistors per unit area increases as the line width of the electronic circuits constituting the semiconductor elements decreases, resulting in smaller electronic equipment and higher performance. As a result, the heat dissipation rate per unit area of the semiconductor element further increased. Such an increase in the heat dissipation rate decreases the performance of the semiconductor element and shortens the lifetime, and eventually reduces the reliability of the system employing the semiconductor element. In particular, in a semiconductor element, various parameter values change sharply depending on the operating temperature, further degrading the characteristics of the integrated circuit.

  In response to such an increase in the heat dissipation rate, a cooling technique for cooling this has also been developed. However, as a known normal cooling technique, a fin-fan cooling method, a thermoelectric element ( There are a Peltier cooling method, a liquid-jet cooling method, an immersion cooling method, a heat pipe cooling method, and the like.

  The fin fan cooling method is a method of forced cooling using fins and / or fans, and has been used for many decades. However, the cooling efficiency is low compared to noise, vibration and large volume. There is. In addition, the thermoelectric element cooling method has no noise and vibration, but has low efficiency. Therefore, there is a problem that a large operating power source is required and an excessively large heat dissipation device is required on the high heat side.

  The liquid jet cooling method is excellent in efficiency and has become the mainstream of cooler research, but its structure is complicated by using a thin film pump that uses an external power supply, and it is highly influenced by gravity. However, there is a problem that robust design is difficult when applied to personal portable electronic equipment.

  Further, in the cooling device using a heat pipe, the flow direction of the gas in the pipe and the liquid are opposite to each other, so that the gas flow from the evaporation section to the condensation section is condensed in the condensation section and returned to the evaporation section. It acts as a flow resistance. Therefore, if a high amount of heat is applied to the heat pipe, the liquid to which the high-speed gas returns cannot return to the evaporation section, and a dry-out phenomenon occurs in which the liquid phase refrigerant is depleted in the evaporation section. Also, the refrigerant vaporized inside the pipe moves depending on the buoyancy and pressure difference, and inside the heat pipe, the liquefied refrigerant depends on the gravity depending on the structure and size of the feedback part medium, so the position where it can be installed Has the problem of many limitations.

  In order to solve such problems, the applicant of the present invention disclosed in Patent Document 1 is a small thin plate in which the cooling performance is hardly affected by gravity and the refrigerant circulates naturally without supplying external power. A mold cooling apparatus has been disclosed. The disclosed thin plate type cooling device includes a thin plate-like housing in which a fluid circulation loop is incorporated, and a refrigerant that changes phase while circulating through the circulation loop in the housing. Comprises a refrigerant storage part that is formed at one end inside the housing and can store a liquid-phase refrigerant, and at least one first fine channel connected to one end of the refrigerant storage part, In the channel, the liquid phase refrigerant is partially filled from the refrigerant storage part to a predetermined part of the first fine channel by surface tension with the inner wall of the first fine channel, and in the first fine channel, The surface tension is set larger than the gravity, and the liquid phase refrigerant filled in the first fine channel can be vaporized by the heat absorbed from the heat source. The vaporization section and the first fine channel of the evaporation section are separated from each other by a predetermined distance on the same plane in the longitudinal direction, and at least the vapor phase refrigerant evaporated and moved in the first fine channel can be condensed. A condensing part that includes one second fine channel, the surface tension of the inner wall of the second fine channel and the condensed refrigerant being set to be greater than gravity, the first fine channel of the evaporation part, and the condensation part A liquid-phase refrigerant separated from the gas-phase refrigerant moving unit by transferring the liquid-phase refrigerant condensed in the condensing unit to the refrigerant storage unit and being separated from the gas-phase refrigerant moving unit. A moving unit.

  According to the disclosed thin plate type cooling device, the refrigerant circulating in the circulation loop inside the housing causes a phase change between the liquid phase and the gas phase, and uses the latent heat at the time of the phase change, thereby cooling the cooling device. Cool the heat of the external heat source that comes into contact with.

  However, according to the disclosed thin plate type cooling device, the gas-phase refrigerant is included in the bubble form in the refrigerant condensed without being completely condensed in the condensing unit, and the liquid-phase refrigerant moving unit and / or the refrigerant There may be a case where the evaporation part is reached through the storage part. Thus, if bubbles are included in the liquid-phase refrigerant and reach the evaporation section, there is a possibility that a dry-out phenomenon occurs in which the liquid-phase refrigerant is depleted in the evaporation section.

Korean Patent Application No. 2001-52584 “Thin Plate Cooling Device”

  An object of the present invention is to improve the above-mentioned problems, and an object of the present invention is to provide a thin plate type cooling device that can prevent a dry-out phenomenon in an evaporation section.

  Another object of the present invention is to provide a thin plate type cooling device that improves the cooling efficiency by improving the flow of the refrigerant.

  To achieve the above object, the present invention provides a thin plate-like housing in which a fluid circulation loop is incorporated, a refrigerant capable of causing a phase change, and circulating in the circulation loop in the housing, A circulation loop in the housing is formed at one end of the inside of the housing, but the liquid phase refrigerant is at least partially filled by capillary action, and the filled liquid phase refrigerant is transmitted from an external heat source. An evaporation section that is vaporized by the generated heat, and a passage that is formed adjacent to the evaporation section, and in which the vaporized refrigerant moves toward the branch portion, and contains a gas phase refrigerant that is not condensed. A gas phase refrigerant moving part comprising at least one first cavity, a condensing part formed in a region adjacent to the gas phase refrigerant moving part, wherein the gas phase refrigerant is condensed into a liquid phase, and the branch Partial A liquid-phase refrigerant moving unit that is formed in a region that is at least a part of the region and is adjacent to the condensing unit, but is thermally insulated from the evaporating unit and condensed in a liquid phase toward the evaporating unit. And a heat insulating part that insulates the evaporating part and at least a part of the liquid-phase refrigerant moving part.

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

  First, referring to FIG. 1A, FIG. 1A is a perspective view schematically illustrating an outer shape of a thin plate cooling device 100 according to a first embodiment of the present invention. The thin plate type cooling device 100 of the present invention preferably has an outer shape formed of a substantially rectangular parallelepiped, and is preferably formed by bonding a substrate 100a and an upper plate 100b on which internal components are formed.

  For the convenience of understanding and explanation, as shown in FIG. 1A, the longitudinal direction (direction from the left side to the right side of the drawing) of the thin plate cooling device 100 of the present invention is defined as the “X-axis direction”. The width direction of the cooling device 100 (the direction toward the drawing) is defined as the “Y-axis direction”, and the height direction of the thin plate cooling device 100 (the direction from the bottom to the top of the drawing) is defined as the “Z-axis”. It is defined as “direction”. Further, a cross section viewed from the negative Z-axis direction (that is, a direction from the lower side to the upper side of the drawing) is referred to as a “cross section viewed from the 'first' direction”, and a positive Z-axis direction (that is, from the upper side of the drawing) A cross section viewed from the lower side) is referred to as “a cross section viewed from the second direction”.

  Referring to FIG. 1B, FIG. 1B is a schematic cross-sectional view of the thin plate type cooling device 100 according to the first embodiment of the present invention, viewed from the ‘second’ direction in the XY plane. As shown in the drawing, the substrate 100a of the thin plate type cooling device 100 is configured so that a refrigerant circulation loop is formed in the substantially rectangular housing 112 by being coupled to the upper plate 100b. The refrigerant is circulated in the direction of the arrow, and cools the heat of the external heat source in contact with the cooling device 100 using latent heat at the time of phase change between the liquid phase and the gas phase.

  The housing 112 includes a semiconductor material such as silicon or gallium, a new material stack material such as Self Assembled Monolayer (SAM), a metal material such as copper or aluminum having excellent thermal conductivity, and / or Alternatively, these materials can be manufactured from various materials such as alloy materials, ceramic materials, polymer materials such as plastic, and crystalline materials such as diamond. In particular, when the external heat source is a semiconductor chip, it can be formed of the same material as the surface material of the external heat source to minimize thermal shock. Further, when the thin plate cooling device 100 is manufactured from a semiconductor material, it may be formed so as to be integrated with the surface material of the external heat source in the manufacturing process of the semiconductor chip to minimize the contact thermal resistance. it can.

  Next, the refrigerant injected into the thin plate type cooling device 100 may be selected from those capable of causing a phase change between the liquid phase and the gas phase by external heat. According to the present embodiment, it is desirable to use water having a large latent heat and surface tension as the refrigerant. This is because it is desirable not to use a Freon (CFC) series refrigerant in consideration of environmental pollution. .

  Further, since the magnitude of the surface tension between the inner wall and the refrigerant varies depending on the material of the thin plate type cooling device 100, in the practice of the present invention, a suitable refrigerant must be selected. For example, in addition to water, an alcohol-based refrigerant such as methanol or ethanol may be used. In the case of the water or alcohol-based refrigerant as described above, the heat capacity is large, the contact angle due to the surface tension with the inner wall of the semiconductor material is small, and the flow rate of the refrigerant is increased, so that it has an advantage that it transfers a large amount of heat. . Also, in the case of water or alcohol-based refrigerants, unlike Freon-type refrigerants, environmental pollution problems do not occur even if they leak from the thin plate cooling device 100 for any reason.

  The selection of such a refrigerant is merely a simple design choice for the implementation of the present invention and does not limit the technical scope of the present invention.

  As shown in the drawing, the thin plate type cooling device 100 is formed at one end of the thin plate type cooling device 100, but the liquid phase refrigerant is at least partially filled by capillary action, and the filled liquid phase refrigerant is externally charged. An evaporation unit 104 that is vaporized by heat transferred from a heat source (not shown), and a vapor phase refrigerant that is formed adjacent to the evaporation unit 104, and in which the vaporized refrigerant moves in a predetermined direction due to the pressure difference. It is formed adjacent to the moving unit 106 and the gas-phase refrigerant moving unit 106, but is formed adjacent to the condensing unit 108 where the gas-phase refrigerant is condensed into a liquid phase, and the condensing unit 108. The liquid phase refrigerant moving units 102 and 110 that are insulated from the evaporation unit 104 and condensed into a liquid phase move toward the evaporation unit 104.

  The evaporation unit 104, the gas-phase refrigerant moving unit 106, the condensing unit 108, and the liquid-phase refrigerant moving units 102 and 110 may be formed only on the substrate 100 a of the thin plate cooling device 100. In addition, the upper plate 100b of the thin plate type cooling device 100 may include only a cavity formed in a predetermined region. The configuration of the upper plate 100b will be described later with reference to FIGS.

  In the thin plate cooling device 100, the refrigerant forms a circulation loop along the arrow direction in the drawing. That is, the refrigerant is circulated through the evaporating unit 104, the vapor-phase refrigerant moving unit 106, the condensing unit 108, the liquid phase refrigerant moving unit 110 on the condensing unit side, and the liquid phase refrigerant moving unit 102 on the evaporating unit side in this order. It is configured as follows.

  In some embodiments of the present invention, a refrigerant storage unit (not shown) having an appropriate volume is further provided so that a predetermined amount of liquid phase refrigerant is stored in a predetermined region of the liquid phase refrigerant moving units 102 and 110. Can be provided. For example, the region of the liquid phase refrigerant moving unit 102 on the evaporation unit side may be used as a refrigerant storage unit. In addition, a plurality of the refrigerant storage units may be formed.

  The evaporation unit 104 is formed adjacent to one end (“exit side”) of the liquid-phase refrigerant moving unit 102 on the evaporation unit side, and a plurality of fine channels are formed in the evaporation unit 104 to form a capillary phenomenon. Thus, at least a part or all of the fine channel is filled with the refrigerant stored in the liquid-phase refrigerant moving unit 102 on the evaporation unit side. In addition, the evaporation unit 104 is installed adjacent to an external heat source (not shown), whereby the liquid phase refrigerant filled in the fine channel is vaporized by the heat transmitted from the heat source. This causes a phase change in the gas phase refrigerant. Therefore, the heat from the heat source is absorbed by the refrigerant as the latent heat due to the phase change of the refrigerant, and the gas phase refrigerant again condenses in the condensing unit 108 to dissipate heat as will be described later. Remove heat.

  It is desirable that the surface tension in the fine channel is formed to be greater than gravity. The smaller the contact angle of the meniscus of the liquid-phase refrigerant filled in the fine channel, the better. For this purpose, the inner wall of the fine channel is formed of a hydrophilic substance or the surface of the fine channel is subjected to hydrophilic treatment. It is desirable. Examples of such hydrophilic treatment include plating treatment, painting treatment, coating treatment, coloring treatment, anodizing treatment, plasma treatment, and laser treatment. In addition, the surface roughness of the inner wall of the fine channel can be adjusted so as to improve the heat transfer coefficient.

  On the other hand, not only the fine channels of the evaporating unit 104 but also the liquid phase refrigerant moving units 110 and 102 and the evaporating unit 104 are subjected to hydrophilic treatment, and the surfaces of the gas phase refrigerant moving unit 106 and the condensing unit 108 are subjected to hydrophobic treatment. Therefore, it is desirable to improve the cooling efficiency by improving the flow of the refrigerant.

  Further, the cross section of the fine channel may be formed to have various shapes such as a circle, an ellipse, a rectangle, a square, and a polygon other than a square. In particular, the surface tension with the refrigerant can be controlled by increasing or decreasing the cross-sectional area along the longitudinal direction of the fine channel (that is, the X-axis direction), and a plurality of grooves or nodes are installed on the inner wall. Thus, the moving direction of the refrigerant can be determined, or the moving speed of the refrigerant can be controlled.

  Next, the refrigerant evaporated in the evaporation unit 104 moves in the opposite direction of the liquid-phase refrigerant moving unit 102 on the evaporation unit side, and thus the gas-phase refrigerant that functions as a passage through which the gas-phase refrigerant can move. A moving part 106 is formed adjacent to the evaporation part 104. As shown in the drawing, the gas-phase refrigerant moving unit 106 may include a plurality of guides 118 so that the vaporized refrigerant can move in a predetermined direction (that is, the reverse direction of the refrigerant storage unit 102). . The guide 118 also has a function of increasing the mechanical strength of the thin plate cooling device 100. Therefore, when there is no problem in mechanical strength, the guide 118 may not be provided.

  Next, the condensing unit 108 is an area where the gas-phase refrigerant that has moved through the gas-phase refrigerant moving unit 106 is condensed again and liquefied. According to this embodiment, the condensing unit 108 is formed at a position separated by a predetermined distance on the same plane as the evaporation unit 104.

  Meanwhile, the condensing unit 108 may include a plurality of fine channels (not shown) similar to the fine channels formed in the evaporation unit 104. As will be described later, the fine channel of the condensing unit 108 is formed to extend to the liquid-phase refrigerant moving unit 110 and further to the liquid-phase refrigerant moving unit 102 on the evaporation unit side. Such a fine channel of the condensing unit 108 further facilitates the condensation of the gas-phase refrigerant and provides a surface tension that moves the condensed liquid-phase refrigerant in the direction of the liquid-phase refrigerant moving unit 102 on the evaporation unit side. This facilitates completion of the refrigerant circulation loop.

  The depth of the fine channel of the condensing unit 108 is preferably deeper than the depth of the fine channel of the evaporation unit 104, but is not limited thereto. In addition, regarding the change in cross-sectional shape, cross-sectional area, and formation of grooves and nodes, all matters relating to the fine channel of the evaporation unit 104 can be applied to the fine channel of the condensing unit 108. Omitted.

  In order to further improve the effect of heat release, a plurality of fins may be formed in the thin plate cooling device 100 outside the condensing unit 108. The fins are formed radially outside the condensing unit 108 or in other predetermined shapes. The heat dissipation effect can be maximized when ambient air contacts between the fins.

  Further, when the fin is formed to include a microactuator, the heat released to the outside from the condensing unit 108 may be recycled to drive the surrounding air to circulate. In addition, when the fin is formed with a fine structure including a thermoelectric element, the heat emitted from the condensing unit 108 may be converted into electric energy and used as energy for fine driving.

  Further, by forming the volume of the condensing unit 108 to be larger than the volume of the evaporating unit 104, the gas phase refrigerant can be easily condensed in the condensing unit 108 only by convection of ambient air.

  Next, the liquid-phase refrigerant moving unit 110 forms a passage through which the liquid-phase refrigerant condensed by the condensing unit 108 moves to the liquid-phase refrigerant moving unit 102 on the evaporation unit side. As illustrated, the liquid-phase refrigerant moving unit 110 is thermally insulated from the gas-phase refrigerant moving unit 106, the condensing unit 108, and the evaporating unit 104 by the heat insulating unit 116.

  The heat insulating part 116 may be configured in the form of an internal partition formed at a predetermined position in the thin plate type cooling device 100, or may be in the form of a separate internal space sealed at a predetermined position in the thin plate type cooling device 100 or The thin plate type cooling device 100 may be configured to be open so as to penetrate the top and bottom of the thin plate type cooling device 100. When the thin plate cooling device 100 is formed in the form of a sealed internal space, the heat insulating part 116 may be kept in a vacuum state or may be filled with a heat insulating material such as air.

  As shown in the drawing, the liquid-phase refrigerant moving unit 110 is preferably formed to be symmetric along both side surfaces of the thin plate type cooling device 100. The refrigerant circulation loop formed symmetrically along the outer periphery of the thin plate type cooling device 100 has a structure that is very advantageous for releasing heat to the surroundings in the form of a thin plate, that is, when the aspect ratio of the cross section is large. Therefore, by diffusing the heat transmitted from the heat source in the radial direction, a large area can be utilized and released to the surroundings.

  In addition, such a bi-directional refrigerant circulation loop is affected by gravity depending on the installation position of the cooling device 100, and the refrigerant circulation in the liquid-phase refrigerant moving unit 110 on either side is not smooth. It has the advantage that the refrigerant can be circulated through the liquid-phase refrigerant moving part 110.

  Of course, as described above, the liquid-phase refrigerant moving unit 110 can also be provided with a fine channel that is hardly affected by gravity, and the refrigerant storage unit 102 is included in the fine channel. A method such as forming a plurality of grooves (not shown) in the direction of heading can be employed. Further, the cross-sectional area of the fine channel formed in the evaporating unit 104 or the liquid phase refrigerant moving units 110 and 102 is from the liquid phase refrigerant moving unit 110 in contact with the condensing unit 108 to the evaporating unit 104 in contact with the gas phase refrigerant moving unit 106. It is desirable to decrease sequentially until it reaches.

  On the other hand, the liquid phase refrigerant moves to the boundary part between the liquid phase refrigerant moving part 102 and the liquid phase refrigerant moving part 110 on the evaporation part side and to the boundary part between the condensing part 108 and the liquid phase refrigerant moving part 110. A plurality of guides (not shown) for defining the direction can be formed to reduce the resistance of the refrigerant circulation generated by the rapid turning of the refrigerant flow path.

  On the other hand, in order to reduce the contact thermal resistance, it is desirable to fix the evaporator 104 in direct contact with a heat source (not shown) adjacent to the evaporator 104 without a heat conductor in the middle. For this reason, in the present embodiment, a fixing means 114 that can fix the cooling device 100 to an external heat source is provided adjacent to the evaporation section 104 and can be fastened with bolts or rivets. Of course, since the fixing means 114 is not related to the circulation of the refrigerant, it may not be provided.

  2A to 2C, the upper plate 100b of the thin plate type cooling device 100 according to the first embodiment of the present invention will be described in detail. FIG. 2A is a schematic cross-sectional view of the thin plate cooling device 100 according to the first embodiment of the present invention, taken along the XY plane, viewed from the “first” direction, and FIG. 2B is a first embodiment of the present invention. FIG. 2C is a schematic cross-sectional view of the thin plate cooling device 100 according to the embodiment taken along the line AA ′ of FIG. 2A, and FIG. 2C is a thin plate cooling device 100 according to the first embodiment of the present invention. It is the schematic sectional drawing which looked at the cross section in YZ plane of FIG. 2A along the BB 'line | wire of FIG. 2A. 2A is a bottom view of the upper plate 100b of the thin plate cooling device 100, as viewed from the ‘first’ direction shown in FIG. 2A.

  As shown in the drawing, according to the present embodiment, the upper plate 100b of the thin plate type cooling device 100 is not condensed in a region corresponding to the gas-phase refrigerant moving part 106 of the substrate 100a. Is provided with a first cavity 124 for providing a marginal space in which the space is accommodated. Further, the upper plate 100b may include a heat insulating portion 116 corresponding to the heat insulating portion 116 of the substrate 100a. The upper plate 100b may be formed of the same material as the housing 112 of the substrate 100a. Alternatively, the upper plate 100b may be formed using a material such as glass.

  Referring to FIG. 2C, the first cavity 124 is formed to have a semi-elliptical cross section in a direction parallel to the Y axis on the YZ plane. The first cavity 124 provides a marginal space in which the gas-phase refrigerant is accommodated, so that the gas-phase refrigerant that is not condensed in the condensing unit 108 is contained in the condensed liquid-phase refrigerant and becomes a bubble. To prevent becoming.

  Next, the upper plate 100b of the thin plate cooling device 100 according to the second embodiment of the present invention will be described in detail with reference to FIGS. 3A to 3C. FIG. 3A is a schematic cross-sectional view of the thin plate type cooling device 100 according to the second embodiment of the present invention in the XY plane as viewed from the 'first' direction, and FIG. 3B is a second embodiment of the present invention. FIG. 3C is a schematic cross-sectional view of the thin plate cooling device 100 according to the embodiment, taken along the line AA ′ of FIG. 3A, and FIG. 3C is a thin plate cooling device 100 according to the second embodiment of the present invention. It is the schematic sectional drawing which looked at the cross section in YZ plane of FIG. 3 along the BB 'line | wire of FIG. 3A. 3A is a bottom view of the upper plate 100b of the thin plate type cooling device 100, as viewed from the ‘first’ direction illustrated in FIG. 3A.

  As illustrated, according to the present embodiment, a plurality of upper plates 100b corresponding to the gas-phase refrigerant moving unit 106 are formed on the upper plate 100b by the second guides 118 of the gas-phase refrigerant moving unit 106. A plurality of first cavities 124 each having a semi-elliptical cross section on the YZ plane are provided corresponding to the moving paths of the gas-phase refrigerant. The first cavity 124 of the second embodiment differs from the first cavity 124 of the first embodiment described above only in that it is separated so as to correspond to the second guide 118 of the substrate 100a. Its function and shape are the same as in the first embodiment.

  4A to 4C, the upper plate 100b of the thin plate type cooling device 100 according to the third embodiment of the present invention will be described in detail. FIG. 4A is a schematic cross-sectional view of the thin plate cooling device 100 according to the third embodiment of the present invention in the XY plane as seen from the “first” direction, and FIG. 4B is a third embodiment of the present invention. 4C is a schematic cross-sectional view of the thin plate cooling device 100 taken along the line AA ′ of FIG. 4A, and FIG. 4C is a cross-sectional view of the thin plate cooling device 100 according to the third embodiment of the present invention. It is the schematic sectional drawing which looked at the cross section in YZ plane along the BB 'line | wire of FIG. 4A. 4A is a bottom view of the upper plate 100b of the thin plate cooling device 100, as viewed from the 'first' direction shown in FIG. 4A.

  As illustrated, the thin plate type cooling apparatus 100 according to the third embodiment of the present invention further includes a plurality of second cavities 126 formed in a region corresponding to the condensing unit 108 of the substrate 100a. That is, the upper plate 100b is formed in a plurality of first cavities 124 formed in a region corresponding to the gas-phase refrigerant moving part 106 of the substrate 100a and a region corresponding to the condensing part 108 of the substrate 100a. The first and second cavities 124 and 126 are formed to be connected to each other.

  In addition, as shown in the drawing, each of the second cavities 126 is preferably formed such that the width thereof becomes narrower toward the region corresponding to the liquid-phase refrigerant moving unit 110. In this way, when the substrate 100a and the upper plate 100b are coupled, the cross-sectional area of the second cavity 126 decreases sequentially toward the liquid-phase refrigerant moving unit 110, and thus the condensed refrigerant Therefore, the gas phase refrigerant that has not been condensed by the condensing unit 108 returns to the first cavity 124 in the region corresponding to the gas phase refrigerant moving unit 106. Therefore, it is possible to more effectively prevent the uncondensed gas-phase refrigerant from being included in the liquid-phase refrigerant in the form of bubbles and reaching the evaporator 104.

  5A to 5D, the upper plate 100b of the thin plate cooling device 100 according to the fourth embodiment of the present invention will be described in detail. FIG. 5A is a schematic cross-sectional view of the thin plate cooling device 100 according to the fourth embodiment of the present invention, taken along the XY plane, as viewed from the “first” direction, and FIG. 5B is a fourth embodiment of the present invention. FIG. 5C is a schematic cross-sectional view of the thin plate cooling device 100 according to the embodiment, taken along the line AA ′ in FIG. 5A, and FIG. 5C is a thin plate cooling device 100 according to the fourth embodiment of the present invention. FIG. 5D is a schematic cross-sectional view taken along the line BB ′ of FIG. 5A, and FIG. 5D is a cross-sectional view of the thin plate cooling device 100 according to the fourth embodiment of the present invention on the YZ plane. FIG. 5b is a schematic cross-sectional view taken along line CC ′ of FIG. 5a. 5A is a bottom view of the upper plate 100b of the thin plate type cooling device 100. FIG.

  As illustrated, according to the present embodiment, the upper plate 100b further includes a plurality of third cavities 128 formed in a region corresponding to the liquid-phase refrigerant moving part 110 of the substrate 100a. Each of the third cavities 128 is preferably formed in a hemispherical shape. The plurality of third cavities 128 may be formed in a plurality of rows along the liquid-phase refrigerant moving unit 110.

  According to the present embodiment, when the gas-phase refrigerant that has not been condensed in the condensing unit 108 moves to the liquid-phase refrigerant moving unit 110 while being included in the liquid-phase refrigerant in the form of bubbles, The plurality of third cavities 128 capture bubble-shaped gas-phase refrigerant. Therefore, it is possible to more effectively prevent the uncondensed gas-phase refrigerant from being included in the liquid-phase refrigerant in the form of bubbles and reaching the evaporator 104.

  The cooling device 100 according to each embodiment of the present invention described above can be manufactured by various currently known methods. For example, a MEMS (Micro Electro Mechanical System) method using a semiconductor element manufacturing process, a SAM (Self Assembled Monolayer), or the like. ) Can be manufactured by applying the method. The manufacturing method will be briefly described with reference to FIGS. 1B and 2A.

  That is, first, the surface of the substrate 100 a of the cooling device 100 is etched to form the refrigerant storage unit 102, the first fine channel 120 of the evaporation unit 104, the first guide 122 of the condensing unit 108, and the second guide of the gas-phase refrigerant moving unit 106. 118 and the liquid-phase refrigerant moving part 110 are formed.

  Next, as described in the above embodiment, the surface of the upper plate 100b is etched to form the cavities 124, 126 and / or 128 and / or the heat insulating portion 116.

  After the substrate 100a and the upper plate 100b having the above-described structure are brought into contact with each other, a voltage is applied to the substrate 100a to perform anode bonding to integrate the housing 112, and separately from the refrigerant storage unit 102 and A refrigerant injection hole (not shown) formed so as to be connected is depressurized so that the circulation loop is substantially vacuum, and then a refrigerant is injected to seal the refrigerant injection hole.

  Although the present invention has been described in detail with respect to the above-described embodiment, it is needless to say that the present invention is not limited thereto and can be variously modified by those skilled in the art. For example, in the configuration of the first embodiment, the cavity corresponding to the condensing unit 108 is deformed to the shape described above with respect to the third example, or the cavity corresponding to the liquid-phase refrigerant moving unit 110 is changed to the fourth embodiment. The present invention can be carried out by modifying the shape into the shape described above. In addition, it goes without saying that the same structure as that of the substrate 100a can be formed in a region other than the region where the cavity of the upper plate 100b is formed in some embodiments.

  According to the present invention, in the thin plate type cooling device, the gas phase that is not condensed in the condensing unit is formed by forming a cavity having a predetermined shape above the gas phase refrigerant moving unit, the condensing unit, and / or the liquid phase refrigerant moving unit. The refrigerant in the gas phase that is not condensed is resident in the channel that leads to the evaporation section, and the refrigerant that has been sufficiently cooled and condensed in the liquid phase is not sufficiently supplied to the evaporation section. The dryout phenomenon that occurs can be prevented.

  Further, according to the present invention, the liquid phase refrigerant is collected in the evaporation section without power by adjusting the surface tension of the liquid phase refrigerant by changing the depth, width or shape of the lower channel. Thus, the dry-out phenomenon does not occur in the evaporation section, and the liquid phase refrigerant can always be sufficiently supplied to the evaporation section.

  In addition, according to the present invention, the upper and lower channels are partially subjected to surface treatment to improve the refrigerant flow and increase the cooling efficiency.

1 is a perspective view schematically illustrating an outer shape of a thin plate type cooling device according to a first embodiment of the present invention. FIG. 3 is a schematic cross-sectional view of a thin plate type cooling device according to the first embodiment of the present invention, as viewed from the ‘second’ direction in a cross section on the XY plane. FIG. 3 is a schematic cross-sectional view of a thin plate type cooling device according to the first embodiment of the present invention, as viewed from the ‘second’ direction in a cross section on the XY plane. 2B is a schematic cross-sectional view of the thin plate cooling device according to the first embodiment of the present invention, taken along the line AA ′ in FIG. 2A, in the YZ plane. FIG. 2B is a schematic cross-sectional view of the thin plate cooling device according to the first embodiment of the present invention taken along the line BB ′ of FIG. 2A in the YZ plane. FIG. FIG. 6 is a schematic cross-sectional view of a thin plate type cooling device according to a second embodiment of the present invention as viewed from the ‘first’ direction in a cross section on an XY plane. FIG. 3B is a schematic cross-sectional view of the thin plate type cooling device according to the second embodiment of the present invention taken along the line AA ′ of FIG. 3A in the YZ plane. FIG. 3B is a schematic cross-sectional view of the thin plate type cooling device according to the second embodiment of the present invention taken along the line BB ′ of FIG. 3A in the YZ plane. It is the schematic sectional drawing which looked at the cross section in XY plane of the thin plate type cooling device by 3rd Embodiment of this invention from the '1st' direction. FIG. 4B is a schematic cross-sectional view of the thin plate type cooling device according to the third embodiment of the present invention taken along the line AA ′ of FIG. 4A in the YZ plane. It is the schematic sectional drawing which looked at the cross section in the YZ plane of the thin plate type cooling device by 3rd Embodiment of this invention along the BB 'line | wire of FIG. 4A. FIG. 6 is a schematic cross-sectional view of a thin plate type cooling device according to a fourth embodiment of the present invention as viewed from a ‘first’ direction in a cross section on an XY plane. FIG. 5B is a schematic cross-sectional view of the thin plate type cooling device according to the fourth embodiment of the present invention taken along the line AA ′ of FIG. 5A in the YZ plane. FIG. 5B is a schematic cross-sectional view of the thin plate type cooling device according to the fourth embodiment of the present invention taken along the line BB ′ of FIG. 5A in the YZ plane. FIG. 5B is a schematic cross-sectional view of the thin plate type cooling device according to the fourth embodiment of the present invention, taken along the line CC ′ of FIG.

Claims (8)

A thin plate-like housing containing a fluid circulation loop inside;
A refrigerant capable of causing a phase change and circulating in a circulation loop in the housing,
The circulation loop in the housing is
An evaporation unit that is formed at one end of the inside, the liquid phase refrigerant is at least partially filled by capillary action, and the filled liquid phase refrigerant is vaporized by heat transferred from an external heat source;
A gas phase comprising at least one first cavity formed adjacent to the evaporating section but serving as a passage for the vaporized refrigerant to move toward the branching portion and containing a non-condensed gas phase refrigerant. A refrigerant moving part;
Formed in a region adjacent to the gas-phase refrigerant moving unit, the condensing unit in which the gas-phase refrigerant is condensed into a liquid phase;
A liquid phase that is formed in a region that is at least a part of the branch portion and that is adjacent to the condensing unit, and that is thermally insulated from the evaporating unit and that is condensed in a liquid phase moves toward the evaporating unit. A refrigerant moving part;
A thin plate type cooling device comprising: a heat insulating portion that insulates the evaporation portion and at least a part of the liquid phase refrigerant moving portion.   The thin plate type cooling device according to claim 1, wherein at least a part of the liquid-phase refrigerant moving unit includes a liquid-phase refrigerant storage unit in which the liquid-phase refrigerant is stored.   The thin plate type cooling device according to claim 2, wherein there are a plurality of liquid phase refrigerant storage units.   The thin-plate cooling device according to claim 2, wherein the liquid-phase refrigerant storage unit includes a fine channel whose surface tension is set to be greater than gravity.   The cross-sectional area of the fine channel of the evaporating part or / and the liquid phase refrigerant moving part decreases sequentially from the refrigerant moving part in contact with the condensing part to the evaporating part in contact with the gas phase refrigerant moving part. The thin plate type cooling device according to 1.   The thin plate type cooling device according to claim 1, wherein the condensing unit includes at least one second cavity.   The thin plate type cooling device according to claim 1, wherein the liquid-phase refrigerant moving unit includes at least one third cavity.   2. The thin plate type cooling device according to claim 1, wherein surfaces of the liquid-phase refrigerant moving unit and the evaporation unit are subjected to hydrophilic treatment, and surfaces of the gas-phase refrigerant moving unit and the condensing unit are subjected to hydrophobic treatment.

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