Ultra-thin vc vapor chamber with partition heat dissipation and design method thereof

Abstract

The application provides an ultrathin VC heat plate with partitioned heat dissipation and a design method thereof, and is mainly suitable for the case that the heating area of an electronic component has multiple high-temperature zones, medium-high-temperature zones and low-temperature zones and overlaps with each other. Multiple cooling zones matched with the heating area of the electronic component are arranged on the lower cover plate of the ultrathin VC heat plate, multiple etching grooves with involute / spiral / epicycloid are arranged in the cooling zones for circulating cooling liquid, and the etching grooves between the cooling zones are independent or partially connected; the position of the initial liquid storage groove is the same as the position of the high-temperature zone / medium-high-temperature zone of the heating area of the electronic component in the zone, and the edge liquid storage groove is arranged at the periphery of the cooling zone. The etching groove is designed in the form of a combined curve, so that the heat dissipation efficiency is improved by more than 30%, the temperature difference of the heating surface is controlled within 1-3 degrees, the operation environment of the heat dissipation component is effectively stabilized, and the operation efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of precision etching technology, and in particular to an ultra-thin VC heat sink with zoned heat dissipation and its design method. Background Technology

[0002] With the advancement of 5G and the diversification and high performance of 5G mobile terminals such as tablets and smartphones, the performance of electronic components such as mobile phone CPUs, PCBs, and batteries is becoming increasingly powerful. However, the integration and assembly density are constantly increasing, leading to a sharp increase in their power consumption and heat generation. Therefore, there is a strong demand for rapid heat conduction and dissipation.

[0003] Currently, VC (Vacuum Coil) heat sinks are widely used for heat dissipation and temperature control of electronic components such as CPUs, PCBs, and batteries. The industry typically employs an etching process to create vacuum chambers on two copper alloy sheets. Then, a 200-250 mesh capillary copper mesh is welded and fixed into the chambers using resistance welding. The copper sheets are then welded together, and the process involves vacuuming, adding coolant, secondary degassing, and spot welding at the head to complete the manufacturing of the VC heat sink.

[0004] like Figure 1 As shown, the existing VC heat sink mainly consists of three components: an upper cover plate 1' serving as the heat dissipation surface, a lower cover plate 2' which contacts the heat-generating electronic components, and a 200-250 mesh capillary copper mesh 3' with a thickness of approximately 0.1 mm placed in the middle of a semi-etched coolant reservoir 6' on the lower cover plate 2'. The lower cover plate 2' also has a coolant filling port 4' and an exhaust port 5' at one end. The side of the lower cover plate 2' opposite to the upper cover plate 1' is the welding surface 7', and the components are welded together using a brazing process.

[0005] When faced with situations where electronic components such as CPUs, PCBs, and batteries have multiple high-temperature, medium-high-temperature, and low-temperature zones that overlap, existing VC heat sinks cannot achieve efficient cooling, making it difficult to further improve the user experience. Furthermore, the large-area etching of the vacuum cavity can lead to insufficient strength, causing collapse, distortion, and low yield when vacuuming.

[0006] To solve the above problems, it is necessary to provide a new type of VC heat sink structure that can stably and efficiently dissipate heat from electronic components while maintaining the strength of the VC heat sink. Summary of the Invention

[0007] According to the technical problem that the heat generation area range size and temperature level of the heat generation electronic component are different and it is difficult to achieve efficient temperature control, a super-thin VC heat plate with partition heat dissipation and a design method thereof are provided, which is especially suitable for the situation that the heat generation area has multiple high temperature zones, medium-high temperature zones and low temperature zones, and the zones overlap each other.

[0008] According to the specific situation of the heat generation electronic component, the etching groove is designed in a targeted manner. The electronic component, such as a circuit board, is detected by an infrared temperature measurement method, so that the temperature, area size and shape of the high temperature zone, medium-high temperature zone and low temperature zone can be directly reflected. Then, according to the position, shape and working temperature of the heat generation component, the etching groove is designed in the form of a combination of involute, Archimedes spiral and epicycloid on the lower cover plate of the VC heat plate. The structures of the cooling liquid phase change flowing out of the etching groove, the cooling liquid phase change flowing back to the etching groove, the initial liquid storage groove, the balanced temperature liquid storage groove and the edge cooling liquid storage groove are designed. The structures of the initial liquid storage groove, the involute / Archimedes spiral / epicycloid etching groove and the edge liquid storage groove described below are all designed by using a half-etching process.

[0009] The heat dissipation efficiency can be improved by more than 30% by using the combined curve form to design the etching groove. The temperature difference of the heat generation surface is controlled within 1-3 degrees, which effectively stabilizes the operating environment of the heat dissipation component and improves the operating efficiency.

[0010] The technical means adopted by the present application are as follows:

[0011] A super-thin VC heat plate with partition heat dissipation, characterized in that a plurality of cooling zones matched with the heat generation area of the electronic component are arranged on the lower cover plate of the super-thin VC heat plate. A plurality of etching grooves with involute / spiral / epicycloid are arranged in the cooling zones for cooling liquid circulation. One end of the etching groove with involute / spiral / epicycloid is connected to the initial liquid storage groove in the cooling zone, and the other end is connected to the edge cooling liquid storage groove. The etching grooves between the cooling zones are independent or partially connected. The position of the initial liquid storage groove is the same as the high temperature zone / medium-high temperature zone of the heat generation area of the electronic component in the region. The edge cooling liquid storage groove is arranged on the outer periphery of the cooling zone.

[0012] Further, the etching groove with involute / spiral / epicycloid is provided with a balanced liquid storage groove.

[0013] Further, the structure of the etching groove with involute / spiral / epicycloid is one or a combination of equal width, gradually narrowing or gradually widening.

[0014] Further, the diameter of the balanced temperature liquid storage groove is 1.5-2 times the width of the corresponding position etching groove.

[0015] Further, the total number of the involute / helical / epicycloid etching channels in the cooling area is N, satisfying: N = number of cooling liquid phase change outflow channels N 出 + number of cooling liquid phase change backflow channels N 回 + number of channels connecting adjacent cooling units N 连 Wherein, when the etching channels between each cooling area are independent of each other, the number of channels connecting adjacent cooling units N 连 = 0.

[0016] Further, when the etching channels between the cooling areas are partially connected, the involute / helical / epicycloid etching channels connecting adjacent cooling areas are in the form of equal width.

[0017] Further, in the cooling area, the cooling liquid phase change outflow channel flowing into the edge cooling liquid reservoir is in the form of gradually widening; the cooling liquid phase change backflow channel flowing from the edge cooling liquid reservoir back to the initial reservoir is in the form of gradually widening.

[0018] Further, a cooling liquid circulation flow adjusting port is provided beside the inlet of the cooling liquid phase change backflow channel, which is in the form of involute structure along the cooling liquid flow direction, and the width of the edge cooling liquid reservoir near the cooling liquid circulation flow adjusting port gradually decreases / increases.

[0019] Further, a wave-shaped channel for increasing the heat dissipation area is etched on the upper cover plate of the ultra-thin VC vapor chamber.

[0020] The application also provides a design method for the above-mentioned ultra-thin VC vapor chamber with partitioned heat dissipation, characterized by comprising the following steps:

[0021] S1, a plurality of cooling areas matching the heat generating areas of electronic components are provided, and an initial reservoir is provided at the location of the high temperature area / medium-high temperature area in the area;

[0022] S2, according to the temperature control requirements of electronic components and the surface temperature difference requirements of the heat dissipation surface, a plurality of etching channels with involute / helical / epicycloid are provided in the cooling area for cooling liquid circulation cooling, according to the design rules of the involute / helical / epicycloid etching channels, a certain number of etching channels are etched on the lower cover plate by using a semi-etching process, and the initial reservoir, the balanced temperature reservoir and the edge cooling liquid reservoir are etched.

[0023] S3, the etching channels between each cooling area are independent or partially connected, when partially connected, the etching channels of equal width are used to connect the initial liquid storage tanks of adjacent cooling areas; the etching channels gradually widen when the cooling liquid flows into the edge cooling liquid storage tank; the phase change return flow channel of the cooling liquid flowing from the edge cooling liquid storage tank to the initial liquid storage tank is gradually widened;

[0024] S4, there are a plurality of balanced temperature liquid storage tanks on each etching channel;

[0025] S5, a cooling liquid circulation flow adjusting port is arranged beside the return flow inlet of the etching channel returning to the initial liquid storage tank, the cooling liquid circulation flow adjusting port is in a gradually opened structure along the cooling liquid flow direction, and the width of the edge cooling liquid storage tank near the cooling liquid circulation flow adjusting port gradually decreases / increases;

[0026] S6, the upper cover plate of the VC heat plate is etched in a wave shape and is welded and fixed with the lower cover plate of the VC heat plate.

[0027] Compared with the prior art, the present application has the following advantages:

[0028] The present application adopts a combined curve form, according to the complexity of the heating area of electronic components, corresponding cooling areas are divided on the lower cover plate of the VC heat plate, the respective characteristics of the involute, Archimedes spiral curve and epicycloid are organically combined together, specifically,

[0029] Involute: the curvature radius of the involute is smaller when it is closer to the base circle (initial liquid storage tank), and the curvature radius is larger when it is farther away from the base circle, the designed etching channel can cover a larger heat dissipation area, and the heat can be quickly transferred from the high temperature area to the low temperature area.

[0030] Archimedes spiral curve: it belongs to an equal speed ratio and equal distance ratio spiral curve, it has the shortest spiral length among various curves passing through two points on the cylinder in the cylinder, the length of the cooling liquid etching channel is shortened, the circulation frequency of the cooling liquid is improved, and the effect of rapid cooling is achieved.

[0031] Epicycloid: it belongs to the characteristics of the brachistochrone and isochronous curve, the circulation time of the cooling liquid in the etching channel is shortened, the circulation frequency of the cooling liquid is improved, and the effect of rapid cooling is achieved.

[0032] Through the combination of the above different curves, the temperature control can be efficiently carried out for the complex heating condition of electronic components, the heat dissipation efficiency can be improved by more than 30%, the temperature difference of the heating surface can be controlled within 1-3 degrees, the total product thickness is in the range of 0.3-0.4mm, and is reduced to ≤0.2mm (the temperature difference of the heating surface of the existing VC heat plate is in the range of 5-10 degrees, and it is difficult to further reduce, and the user experience cannot be further improved), the running environment of the heat dissipation components is effectively stabilized, and the running efficiency is improved; avoid the collapse and distortion caused by the insufficient strength and vacuum absorption due to the large-area etching of the vacuum cavity, and the low yield; at the same time, the processing difficulty of the VC heat plate is reduced, and the problem of high cost is solved.

[0033] Based on the above reasons, the present application can be widely used in the field of precision etching technology. BRIEF DESCRIPTION OF DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0035] Figure 1 It is a combination schematic diagram of the existing VC heat plate.

[0036] Figure 2 It is a combination schematic diagram of the ultra-thin VC heat plate with partitioned heat dissipation of the present application.

[0037] Figure 3 It is a schematic diagram of the upper cover plate of the ultra-thin VC heat plate with partitioned heat dissipation of the present application.

[0038] Figure 4 It is a schematic diagram of the temperature range of the heating electronic component.

[0039] Figure 5 It is a schematic diagram of the lower cover plate of the ultra-thin VC heat plate with partitioned heat dissipation of the present application.

[0040] Figure 6 It is a schematic diagram of the lower cover plate edge liquid storage tank and each cooling liquid outlet / cooling liquid inlet of the ultra-thin VC heat plate with partitioned heat dissipation of the present application.

[0041] Figure 7 It is a partial enlarged view of the etching groove flow of the cooling area II and the cooling area III of the present application.

[0042] Figure 8 It is a schematic diagram of the epicycloid cooling liquid phase change flow into the etching groove in the cooling area III of the present application.

[0043] Figure 9 Schematic diagram of the epitrochoid etching channel in the cooling zone Ⅲ of the present application.

[0044] Figure 10 Schematic diagram of the involute etching channel of equal width extending outward from the initial liquid storage tank Ⅰ in the cooling zone Ⅰ of the present application.

[0045] Figure 11 Schematic diagram of the involute etching channel of gradually increasing width extending outward from the initial liquid storage tank Ⅰ in the cooling zone Ⅰ of the present application.

[0046] Figure 12 Schematic diagram of the involute etching channel of gradually increasing width extending outward from the initial liquid storage tank Ⅰ in the cooling zone Ⅰ of the present application.

[0047] Figure 13 Schematic diagram of the spiral curve etching channel of equal width extending outward from the initial liquid storage tank Ⅱ in the cooling zone Ⅱ of the present application.

[0048] Figure 14 Schematic diagram of the spiral curve etching channel of gradually increasing width extending outward from the initial liquid storage tank Ⅱ in the cooling zone Ⅱ of the present application.

[0049] Figure 15 Schematic diagram of the spiral curve etching channel of gradually increasing width extending outward from the initial liquid storage tank Ⅱ in the cooling zone Ⅱ of the present application.

[0050] In the figure: 1, upper cover plate; 2, lower cover plate; 3, cooling liquid filling port; 4, exhaust port;

[0051] 5, cooling zone Ⅰ; 51, initial liquid storage tank Ⅰ; 52, involute etching channel; 53, balanced temperature liquid storage tank Ⅰ; 54, cooling liquid outflow port of cooling zone Ⅰ; 55, cooling liquid liquefied return 1# inlet of cooling zone Ⅰ; 56, 1# cooling liquid circulation flow adjusting port; 57, 1# connecting port of cooling zone Ⅰ / cooling zone Ⅱ; 58, high temperature zone Ⅰ; 59, medium-high temperature zone Ⅰ; 50, low temperature zone Ⅰ;

[0052] 6, cooling zone Ⅱ; 61, initial liquid storage tank Ⅱ; 62, spiral curve etching channel; 63, balanced temperature liquid storage tank Ⅱ; 64, cooling liquid outflow port of cooling zone Ⅱ; 65, cooling liquid liquefied return 2# inlet of cooling zone Ⅱ; 66, 2# cooling liquid circulation flow adjusting port; 67, 2# connecting port of cooling zone Ⅱ / cooling zone Ⅲ; 68, high temperature zone Ⅱ; 69, medium-high temperature zone Ⅱ; 60, low temperature zone Ⅱ;

[0053] 7, cooling zone Ⅲ; 71, initial liquid storage tank Ⅲ; 72, epitrochoid etching channel; 73, balanced temperature liquid storage tank Ⅲ; 74, cooling liquid outflow port of cooling zone Ⅲ; 75, 3# connecting port of cooling zone Ⅰ / cooling zone Ⅲ; 76, medium-high temperature zone Ⅲ; 77, low temperature zone Ⅲ;

[0054] 8, edge cooling liquid reservoir; 81, cooling liquid flow direction; 9, welding surface (non-half etching surface is welding surface). DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0056] First of all, it should be pointed out that the design method of involute, Archimedes spiral and epicycloid adopted by the present application. The number of etching grooves described below is not limited to this. In actual design, the number of etching grooves can be adjusted according to the requirements of temperature control, temperature uniformity of the heating surface, heat dissipation efficiency and the like. The more the number of etching grooves, the more accurate the temperature control, the higher the temperature uniformity of the heating surface, and the heat dissipation efficiency will be proportionally greatly improved according to the increase in the number of etching grooves, which is suitable for use in the heating area with multiple high temperature zones, medium-high temperature zones and low temperature zones, and the overlapping situation between them.

[0057] For the large area of heat dissipation, the etching grooves are designed in the form of involute:

[0058] As shown in Figure 4 , the large area has a high temperature zone I 58 with a temperature range of 50-60℃, a medium-high temperature zone I 59 with a temperature of 40-50℃, and a low temperature zone I 50 with a temperature of 35-40℃.

[0059] The radius r1 of the low temperature zone I 50 is πD, and the diameter D of the circular initial liquid reservoir I 151 is calculated;

[0060] The position of the circular initial liquid reservoir I 151 is the same as that of the high temperature zone I 58 of the electronic component;

[0061] According to the diameter D of the initial liquid reservoir, six involute etching groove size patterns are designed by equal division in this embodiment.

[0062] For the medium area of heat dissipation, the etching grooves are designed in the form of Archimedes spiral curve:

[0063] The medium area has a high temperature zone II 68 with a temperature range of 50-60℃, a medium-high temperature zone II 69 with a temperature of 40-50℃, and a low temperature zone II 60 with a temperature of 35-40℃.

[0064] The radius r2 of the high temperature zone II 68 is taken as the radius of the initial liquid reservoir II 61;

[0065] The position of the initial liquid storage tank 161 is the same as that of the high-temperature area 168 of the electronic component.

[0066] The Archimedes spiral curve formula can be expressed by the specified radius r, the peripheral velocity v, and the linear motion velocity ω, and the formula is: p = r x ((ω / v) x θ + 1). The cooling liquid in the initial liquid storage tank 161 expands under the heat and flows from the center position to each outlet with the linear motion velocity ω which is approximately equal to the peripheral velocity v along the periphery of the initial liquid storage tank 161. The Archimedes spiral curve formula is derived as: p = r x (θ + 1) under the condition of ω ≈ v. r2 is the known radius of the high-temperature area 168. The Archimedes spiral curve belongs to the equal-speed ratio and equal-distance ratio spiral curve. Under the condition of different temperatures in the high-temperature area, the flow velocity of the cooling liquid will change accordingly, but no matter how the flow velocity of the cooling liquid changes, the linear motion velocity ω and the peripheral velocity v change at the same ratio, and ω / v ≈ 1 is basically unchanged, and the curve shape and the pitch are unchanged. Accordingly, the 45° tangent method is adopted to design the Archimedes spiral curve etched channel, and this embodiment is described by taking the circular initial liquid storage tank 161 as an example, in which six Archimedes spiral curve etched channels are uniformly distributed on the periphery of the circular initial liquid storage tank 161.

[0067] The etched channel is designed in the form of an outer cycloid for a small area of the heat dissipation area.

[0068] The small area has a medium-high temperature area 176 with a temperature of 40-50℃ and a low temperature area 177 with a temperature of 35-40℃.

[0069] The radius r3 of the medium-high temperature area 176 is taken as the radius of the circular initial liquid storage tank 171, and the span between the medium-high temperature area 176 and the low temperature area 177 is taken as the diameter d of the outer cycloid moving circle.

[0070] The position of the initial liquid storage tank 171 is the same as that of the medium-high temperature area 176 of the electronic component.

[0071] The ratio between the base circle radius r3 and the moving circle radius d / 2 is an integer (if not, the base circle radius r or the diameter of the moving circle can be finely adjusted), and if the ratio is not an integer, the outer cycloid cannot be closed. The cycloid is the brachistochrone and the isochronous curve, and the area under the cycloid is three times the area of the moving circle. Under the condition of different temperatures in the medium-high temperature area 176, the flow velocity of the cooling liquid will change accordingly, but no matter how the flow velocity of the cooling liquid changes, the cooling liquid will reflect the isochronous nature of the corresponding flow velocity under the corresponding temperature condition, and the moving speed between two points is the fastest. Accordingly, the ratio between the base circle radius r3 and the moving circle radius d / 2 is 5 to design the outer cycloid etched channel, and this embodiment is described by taking the circular initial liquid storage tank 171 as an example, in which three outer cycloid etched channels are uniformly distributed on the periphery of the circular initial liquid storage tank 171.

[0072] Embodiment 1

[0073] As Figure 2 shown, the present application provides a super-thin VC vapor chamber with partitioned heat dissipation, which is etched with grooves on the lower cover plate 2 according to the aforementioned curve combination form. As Figure 5 shown, the lower cover plate 2 is provided with a cooling liquid filling port 3 and an exhaust port 4 at the upper end, and three cooling areas matching the heat-emitting areas of electronic components are arranged on the lower cover plate 2, which are cooling area I 5 matching the large-area heat dissipation area, cooling area II 6 matching the medium-area heat dissipation area, and cooling area III 7 matching the small-area heat dissipation area. Correspondingly, six involute etched grooves 52 are arranged in the cooling area I 5, six spiral etched grooves 62 are arranged in the cooling area II 6, and three epicycloid etched grooves 72 are arranged in the cooling area III 7.

[0074] The single cooling area is for temperature control and balance of the corresponding area. In this embodiment, the cooling liquid circulation cooling form in the cooling area is described by taking the example that the cooling areas are interconnected, that is, the etched groove parts are partially connected.

[0075] To simplify the complex circulation form, the three cooling areas can also be independent of each other, and each independently circulates to mix, equalize temperature, and cool the cooling liquid through the edge cooling liquid storage tank, so as to finally achieve the temperature control purpose of the whole cooling area, which will not be described here.

[0076] The following describes the interconnection between the three cooling areas.

[0077] Cooling area I

[0078] The total number of etched grooves in the cooling area I 5 is 6, of which N 出 is 3, which directly flows into the edge cooling liquid storage tank 8 through the cooling liquid outlet 54 (as Figure 6 shown) of the cooling area I; N 回 is 1, which returns to the initial storage tank I 51 through the cooling liquid return 1# inlet 55 of the cooling area I; N 连 is 2, one of which connects the Archimedes spiral etched groove in the cooling area II 6 through the 1# connecting port 57 of the cooling area I / cooling area II, and the other of which connects the epicycloid etched groove in the cooling area III 7 through the 3# connecting port 75 of the cooling area I / cooling area III.

[0079] In the cooling area I 5, the cooling liquid is heated and vaporized, and the two involute etched grooves Figure 5 (in which the balance storage tank is marked by a black dot in the etched groove) flow from the circular initial storage tank I 51 to the circular initial storage tank II 61 and the circular initial storage tank III 71 (the arrow in the figure shows the cooling liquid flow direction 81), and the etched groove width is constant, as Figure 10 shown.

[0080] Cooling liquid is heated and vaporized, 3 etching channels flow from the initial liquid tank 151 to the edge cooling liquid tank 8, the etching channel gradually widens, as shown in Figure 11 .

[0081] After the cooling liquid is cooled and liquefied, 1 etching channel flows from the edge cooling liquid tank 8 to the initial liquid tank 151 through the cooling area I cooling liquid liquefied return 1# inlet 55 (as shown in Figure 5 , the balance liquid tank is marked as the etching channel where the black semicircle point is located), the etching channel gradually widens along the direction of the initial liquid tank 151, as shown in Figure 12 .

[0082] The circular balance temperature liquid tank 153 is on the node of the involute 12, and the diameter is 1.5-2 times the width of the etching channel at the corresponding position, which is a key structure form for further uniform and balanced heat dissipation surface.

[0083] Cooling area II

[0084] The total number of etching channels in the cooling area II 6 is 6, of which N 出 is 3, which directly flows into the edge cooling liquid tank 8 through the cooling area II cooling liquid outlet 64; N 回 is 1, which returns to the initial liquid tank II 61 through the cooling area II cooling liquid liquefied return 2# inlet 65; N 连 is 2, one is connected with the involute etching channel in the cooling area I 5, and the other is connected with the epicycloid etching channel in the cooling area III 7 through the 2# connecting port 67 of the cooling area II / cooling area III.

[0085] In the cooling area II 6, the cooling liquid is heated and vaporized, 1 etching channel flows from the initial liquid tank II 61 to the initial liquid tank III 71, and the etching channel width is constant, as shown in Figure 13 .

[0086] Cooling liquid is heated and vaporized, 3 etching channels flow from the initial liquid tank II 61 to the edge cooling liquid tank 8, the etching channel gradually widens, as shown in Figure 14 .

[0087] After the cooling liquid is cooled and liquefied, 1 etching channel flows from the edge cooling liquid tank 8 to the initial liquid tank II 61 through the cooling area II cooling liquid liquefied return 2# inlet 65 (as shown in Figure 7 , the balance liquid tank is marked as the etching channel where the black semicircle point is located), the etching channel gradually widens along the direction of the initial liquid tank II 61, as shown in Figure 15 .

[0088] Balanced temperature storage tank II 63 is at the point of 45° tangent of Archimedes spiral curve, and the diameter is 1.5-2 times of the width of etching groove at the corresponding position, which is the key structure form for further uniform and balanced heat dissipation surface heat dissipation effect.

[0089] Cooling area III

[0090] The etching grooves in cooling area III 7 are 3, of which 2 are communicated with cooling area I 5 and cooling area II 6 respectively, and 1 is a cooling liquid outflow channel, which directly flows into the edge cooling liquid storage tank 8 through the cooling liquid outlet 74 of cooling area III. The three etching grooves are evenly distributed at the periphery of the initial storage tank III 71 with the center of the initial storage tank III 71 as the base point. The initial storage tank I 51 and the initial storage tank II 61 are communicated by the equal-width etching groove as shown in Figure 8 .

[0091] The cooling liquid flowing into the initial storage tank III 71 from the initial storage tank I 51 and the initial storage tank II 61 is vaporized by heat, enters the edge cooling liquid storage tank 8 through the cooling liquid outlet 74 of cooling area III, and the width of the etching groove gradually increases as shown in Figure 9 . The balanced temperature storage tank III 73 is at the intersection of the three etching grooves, and the diameter is 1.5-2 times of the width of the etching groove at the corresponding position, which is the key structure form for further uniform and balanced heat dissipation surface heat dissipation effect.

[0092] VC heat sink processing:

[0093] The VC heat sink designed in the application only has an upper cover plate 1 and a lower cover plate 2, two components, and does not use 200-250 mesh copper mesh, effectively reducing the process complexity and product cost. The specific design method comprises the following steps:

[0094] A semi-etching process is used on the lower cover plate 2 to etch the etching grooves of each cooling area, the initial storage tank, the balanced temperature storage tank, the edge cooling liquid storage tank 8, the cooling liquid filling port 3, the exhaust port 4 and other structures, and a semi-etching process is used on the upper cover plate 1 to etch a wave-shaped heat dissipation surface (the etching grooves of the lower cover plate can also be mirror-etched, and the etching depth can be designed according to the actual temperature control requirements of electronic components, and the etching depth can be 25-60% of the material thickness) → using atomic diffusion welding, the upper and lower cover plates are welded into one through the welding surface 9 (the non-semi-etched surface is a welding surface) to form a closed circulating etching groove → vacuumizing and filling cooling liquid → secondary degassing → welding the liquid filling port and the exhaust port, to complete the manufacturing of the VC heat sink.

[0095] The upper cover plate 1 and the lower cover plate 2 can use copper alloy materials with t=0.08-0.1 mm, so that the total thickness of the VC vapor chamber is reduced to 0.16-0.2 mm, and the total thickness is reduced by 40%-60% based on the original 0.3-0.4 mm; the upper cover plate 1 is etched into a wave shape (as shown in the figure), which increases the heat dissipation area, enhances the heat dissipation effect, effectively reduces the weight, and comprehensively reduces the weight by more than 30%. Figure 3

[0096] The processing method of the present application does not use large-area etching of the vacuum cavity, which avoids the problems of insufficient strength of the lower cover plate, collapse and distortion caused by vacuum suction, and low yield.

[0097] The working principle of the VC vapor chamber is as follows:

[0098] The working process of the present application is described in combination with Figure 5 , Figure 6 and Figure 7 .

[0099] The initial liquid storage tank I 51 and the initial liquid storage tank II 61 are located at the positions of the high-temperature area I 58 and the high-temperature area II 68 of the electronic component heating area, respectively. The cooling liquid is vaporized (the pressure is increased) by heat, and the cooling liquid flows from the initial liquid storage tank I 51 to the initial liquid storage tank II 61 and the initial liquid storage tank III 71 at the same time, that is, two equal-width involute etched channels are in communication with the initial liquid storage tank I 51, one of which enters the spiral etched channel through the 1# connecting port 57 of the cooling area I / cooling area II and flows into the initial liquid storage tank II 61, and the other enters the cycloid etched channel through the 3# connecting port 75 of the cooling area I / cooling area III and flows into the initial liquid storage tank III 71; one equal-width spiral etched channel in communication with the initial liquid storage tank II 61 enters the cycloid etched channel through the 2# connecting port 67 of the cooling area II / cooling area III and flows into the initial liquid storage tank III 71.

[0100] There are three etched channels in communication with the edge cooling liquid storage tank 8 on the initial liquid storage tank I 51 and the initial liquid storage tank II 61, respectively, and there is one etched channel in communication with the edge cooling liquid storage tank 8 on the initial liquid storage tank III 71; there is one etched channel for returning the cooling liquid from the edge cooling liquid storage tank 8 on the initial liquid storage tank I 51 and the initial liquid storage tank II 61, respectively.

[0101] There are 1# cooling liquid circulation flow adjusting port 56 and 2# cooling liquid circulation flow adjusting port 66 beside the 1# cooling liquid liquefied return inlet 55 of the cooling area I and the 2# cooling liquid liquefied return inlet 65 of the cooling area II, respectively, which can increase the pressure of the cooling liquid returning to the initial liquid storage tank I 51 and the initial liquid storage tank II 61, and ensure the normal circulation of the cooling liquid in the edge cooling liquid storage tank 8.

[0102] ​1# and 2# cooling liquid circulation flow regulating ports 56 and 66 gradually increase along the cooling liquid flow direction 81; the width of the cooling liquid reservoir 8 gradually decreases at the edge of the 1# cooling liquid circulation flow regulating port 56 and gradually increases at the edge of the 2# cooling liquid circulation flow regulating port 66; the 2# cooling liquid circulation flow regulating port 66 simultaneously plays a relay pressurization role.

[0103] The cooling liquid phase change flowing out of the etching groove and the cooling liquid phase change flowing back to the etching groove width between the initial reservoir and the edge cooling liquid reservoir are designed according to the actual temperature control requirements of electronic components.

[0104] The balanced temperature reservoir is on the etching groove, and the diameter is 1.5-2 times the width of the etching groove at the corresponding position, to balance the temperature difference at the local position, and there are four cases:

[0105] ① The vaporized cooling liquid flows through the high-temperature area, balances the temperature of the high-temperature area through heat conduction, and then flows into the edge cooling liquid reservoir.

[0106] ② The vaporized cooling liquid flows through the low-temperature area, and the heat is taken away by the liquidized cooling liquid after the vaporized cooling liquid flows through the low-temperature area, and then flows into the edge cooling liquid reservoir.

[0107] ③ The liquidized cooling liquid flows through the high-temperature area, and the heat of the high-temperature area is taken away by the cooling liquid vaporization, and then flows into the edge cooling liquid reservoir.

[0108] ④ The liquidized cooling liquid flows through the low-temperature area, and the temperature of the low-temperature area is balanced through heat conduction, and then flows into the edge cooling liquid reservoir.

[0109] The pressure difference between the vaporization of the cooling liquid in the initial reservoir and the liquefaction of the cooling liquid in the edge cooling liquid reservoir, and the pressure adjustment of the 1# and 2# cooling liquid circulation flow regulating ports, push the cooling liquid to flow from the initial reservoir in the high-temperature area to the edge cooling liquid reservoir through the etching groove, and backflow to the initial reservoir I 51 and the initial reservoir II 61 through the cooling liquid liquefaction backflow 1# and 2# inlet. To ensure the required pressure for rapid circulation of the cooling liquid, the flow cross-sectional area of the 1# and 2# cooling liquid circulation flow regulating ports can be adjusted to increase the initial pressure of the cooling liquid backflow to the initial reservoir I 51 and the initial reservoir II 61, to ensure the normal and rapid circulation of the cooling liquid in the edge cooling liquid reservoir. The number of various curves, the diameter of the balanced temperature reservoir, the cooling liquid circulation flow regulating port, and the etching groove width can be designed according to the temperature control and surface temperature difference control requirements of the product.

[0110] The heat of the electronic components to which the present application is applicable is persistent, such as the smart phones of mobile terminals are used for a long time, even if in standby state the related electronic components will still generate heat, the cooling liquid is continuously circulated in the etching tank, has the anti-gravity characteristic, and is not affected by the attitude in the use process. (For example, taking pure water as the cooling liquid as an example, in the state of 1000 Pa of atmospheric pressure, the vaporization temperature of the pure water is 6.9696 ℃, which is far lower than the temperature of the electronic components, which means that the cooling liquid will continuously circulate, the higher the temperature of the electronic components, the faster the circulation speed, and the corresponding greater the heat flow density (unit: W / cm 2 ), the heat dissipation power per unit volume (unit: W / cm 3 ), the weight heat dissipation power (unit: W / g) and the like.

[0111] The above embodiments are only the preferred embodiments of the present application, and are not used to limit the present application; although the present application is described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. An ultra-thin VC heat sink with zoned heat dissipation, characterized in that, The heating areas of the electronic components are detected by infrared thermometry, measuring the temperature, area, and shape of the high-temperature, medium-high-temperature, and low-temperature regions. Based on the location, shape, and operating temperature of the heating components, multiple cooling zones matching the heating areas of the electronic components are set on the lower cover of the ultra-thin VC heat spreader. Each cooling zone contains multiple etched channels with involute, spiral, and epicycloid patterns for coolant circulation and cooling. One end of each involute, spiral, or epicycloid etched channel is connected to the initial coolant reservoir within the corresponding cooling zone, and the other end is connected to an edge coolant reservoir. The etched channels between each cooling zone are independent or partially connected. The initial coolant reservoir is located at the same position as the high-temperature region of the electronic component's heating area within that zone, or at the same position as the medium-high-temperature region of the electronic component's heating area within that zone. The edge coolant reservoir is located on the outer periphery of the cooling zone. Temperature-balanced liquid storage tanks are provided on the etching channels of involute, spiral, and epicycloid lines. The etched grooves of involute, spiral, and epicycloid are one or more of the following structures: equal width, gradually narrowing, or gradually widening. The diameter of the balanced temperature storage tank is 1.5 to 2 times the width of the corresponding etching channel; The total number of involute, spiral, and epicycloid etched channels in the cooling zone is N, satisfying: N = number of coolant phase change outflow channels N 出 +Number of coolant phase change reflux channels N 回 +Number of channels connecting adjacent cooling units N 连 Where the etching channels between each cooling zone are independent of each other, the number of channels N connecting adjacent cooling units is... 连 =0; The total thickness of the VC heat spreader is 0.16~0.2mm.

2. The ultra-thin VC heat sink with zoned heat dissipation according to claim 1, characterized in that, When the etching channels between the cooling zones are partially connected, the etching channels connecting the involute, spiral, and epicycloid of adjacent cooling zones have a structure of equal width.

3. The ultra-thin VC heat sink with zoned heat dissipation according to claim 2, characterized in that, In the cooling zone, the coolant phase change outflow channel flowing into the edge coolant reservoir has a gradually widening structure; the coolant phase change return channel flowing back from the edge coolant reservoir to the initial reservoir also has a gradually widening structure.

4. The ultra-thin VC heat sink with zoned heat dissipation according to claim 3, characterized in that, A coolant circulation flow regulating port is provided next to the inlet of the coolant phase change reflux channel. The coolant circulation flow regulating port has a gradually opening structure along the coolant flow direction. The width of the coolant storage tank gradually decreases at the edge of the No. 1 coolant circulation flow regulating port and gradually increases at the edge of the No. 2 coolant circulation flow regulating port.

5. The ultra-thin VC heat sink with zoned heat dissipation according to claim 1, characterized in that, The top cover of the ultra-thin VC heat sink is etched with wavy channels to increase the heat dissipation area.

6. A design method for an ultra-thin VC heat sink with zoned heat dissipation as described in any one of claims 1-5, characterized in that... Includes the following steps: S1. Set up multiple cooling zones that match the heat generation areas of electronic components, and set up initial liquid storage tanks at the locations of the high-temperature zone and the medium-high temperature zone within these zones. S2. According to the temperature control requirements of electronic components and the surface temperature difference requirements of heat dissipation surface, multiple etching channels with involute, spiral and epicycloid combination are set in the cooling zone for coolant circulation and cooling. According to the design rules of involute, spiral and epicycloid etching channels, a certain number of etching channels are etched on the lower cover plate using a semi-etching process, including initial liquid storage tank, equilibrium temperature liquid storage tank and edge coolant liquid storage tank. S3. The etching channels between each cooling zone are independent or partially connected. When partially connected, the initial liquid storage tanks of adjacent cooling zones are connected by etching channels of equal width. The etching channels flowing from the initial liquid storage tank into the edge coolant storage tank gradually become wider. The etching channels flowing back from the edge coolant storage tank to the initial liquid storage tank gradually become wider. S4. Each etching channel has a number of equilibrium temperature storage tanks. S5. A coolant circulation flow rate regulating port is set next to the return inlet of the etching channel that returns to the initial storage tank. The coolant circulation flow rate regulating port has a gradually opening structure along the coolant flow direction. The width of the coolant storage tank gradually decreases at the edge of the #1 coolant circulation flow rate regulating port and gradually increases at the edge of the #2 coolant circulation flow rate regulating port. The upper cover plate of the S6 and VC heat exchanger plates is etched into a wavy shape and welded to the lower cover plate of the VC heat exchanger plate.

Images