Preparation method for diamond radiating fin, and diamond radiating fin

Abstract

Disclosed in the present application are a preparation method for a diamond radiating fin, and a diamond radiating fin. The method comprises: providing a substrate comprising a first side surface and a second side surface that are opposite each other; forming a solder layer on the first side surface of the substrate; laying a diamond layer on the side of the solder layer that is away from the substrate, wherein the diamond layer comprises a plurality of diamonds; sintering the substrate, the solder layer and the diamond layer; and arranging a conductive circuit layer on a surface of the side of the diamond layer that is away from the solder layer to form the diamond radiating fin.

Description

Preparation method of diamond heat sink and diamond heat sink

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on September 26, 2023, with application number 202311265420.8. The entire contents of the above application are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of laser technology, and in particular to a method for preparing a diamond heat sink and a diamond heat sink. Background Art

[0003] With the continuous increase in the output power of high-power devices such as microwave devices, power electronics, and lasers, the heat dissipation requirements for high-power devices are also becoming higher and higher. Traditional packaging materials are limited by the thermal conductivity of their own materials and cannot achieve efficient heat dissipation, resulting in higher junction temperatures of high-power devices and affecting their performance.

[0004] Diamond, as the material with the highest known thermal conductivity, is the best material for solving the heat dissipation problem of high-power devices. However, due to the limitations of the diamond growth process, the size of diamond is small, making it difficult to use it as a heat sink to dissipate heat from high-power devices. SUMMARY OF THE INVENTION

[0005] The embodiments of the present application provide a method for preparing a diamond heat sink and a diamond heat sink, aiming to solve the problem in the prior art that, due to the limitations of the diamond growth process, the size of diamonds is small and it is difficult to use them as heat sinks to dissipate heat for high-power devices.

[0006] The present invention provides a method for preparing a diamond heat sink, the method comprising:

[0007] Providing a substrate, wherein the substrate is a copper foil, and the substrate includes a first side surface and a second side surface opposite to each other;

[0008] forming a solder layer on the first side of the substrate;

[0009] Grinding and polishing the surface of the diamond layer facing away from the solder layer;

[0010] Laying a diamond layer on a side of the solder layer facing away from the substrate, wherein the diamond layer includes a plurality of diamonds;

[0011] sintering the substrate, the solder layer, and the diamond layer within a first preset temperature range, wherein the first preset temperature range is less than or equal to 800° C.;

[0012] Disposing a conductive circuit layer on a surface of the diamond layer facing away from the solder layer to form a diamond heat sink;

[0013] The diamond heat sink is cut to form a plurality of sub-heat sinks.

[0014] The present invention also provides a method for preparing a diamond heat sink, the method comprising:

[0015] providing a substrate comprising a first side and a second side facing each other;

[0016] forming a solder layer on the first side of the substrate;

[0017] Laying a diamond layer on a side of the solder layer facing away from the substrate, wherein the diamond layer includes a plurality of diamonds;

[0018] sintering the substrate, the solder layer, and the diamond layer;

[0019] A conductive circuit layer is provided on a surface of the diamond layer facing away from the solder layer to form a diamond heat sink.

[0020] In some embodiments, sintering the substrate, the solder layer, and the diamond layer includes:

[0021] The substrate, the solder layer and the diamond layer are placed in a first preset temperature range for sintering, and the first preset temperature range is less than or equal to 800°C.

[0022] In some embodiments, before sintering the substrate, the solder layer, and the diamond layer, the method further comprises:

[0023] The substrate, solder layer and diamond layer are fixed by a clamp.

[0024] In some embodiments, before providing a conductive circuit layer on a surface of the diamond layer facing away from the solder layer, the method further comprises:

[0025] The surface of the diamond layer facing away from the solder layer is ground and polished.

[0026] In some embodiments, before grinding and polishing the surface of the diamond layer facing away from the solder layer, the method further comprises:

[0027] providing a first support plate;

[0028] The second side surface of the substrate is connected to a side surface of the first support plate.

[0029] In some embodiments, connecting the second side surface of the substrate to a side surface of the first support plate includes:

[0030] The second side surface of the substrate is bonded to one side surface of the first support plate by an adhesive.

[0031] In some embodiments, the first support plate is a sapphire plate or a glass plate.

[0032] In some embodiments, the thickness of the substrate is greater than or equal to 150 μm and less than or equal to 500 μm;

[0033] The length of the substrate is greater than or equal to 100 mm; or the width of the substrate 210 is greater than or equal to 100 mm.

[0034] In some embodiments, providing a conductive circuit layer on a surface of the diamond layer facing away from the solder layer includes:

[0035] Depositing a seed layer on a surface of the diamond layer facing away from the solder layer;

[0036] forming a conductive layer on a surface of the seed layer facing away from the diamond layer;

[0037] The conductive layer and the seed layer are etched to form the conductive circuit layer.

[0038] In some embodiments, the seed layer is made of titanium / copper or chromium / copper.

[0039] In some embodiments, after etching the conductive layer and the seed layer to form the conductive circuit layer, the method further includes:

[0040] The surface of the conductive circuit layer facing away from the diamond layer is ground so that the thickness of the conductive circuit layer reaches a preset thickness.

[0041] In some embodiments, before grinding the surface of the conductive circuit layer facing away from the diamond layer, the method further includes:

[0042] providing a second support plate;

[0043] The second side surface of the substrate is connected to a side surface of the second support plate.

[0044] In some embodiments, the second support plate is a sapphire plate or a glass plate.

[0045] In some embodiments, connecting the second side surface of the substrate to a side surface of the second support plate includes:

[0046] The second side surface of the substrate is bonded to one side surface of the second support plate by an adhesive.

[0047] In some embodiments, the substrate is made of metal; and the method further comprises:

[0048] peeling the substrate from one side surface of the second support plate;

[0049] A first metal layer is formed on the second side surface of the substrate.

[0050] In some embodiments, the material of the first metal layer includes nickel / gold, or silver.

[0051] In some embodiments, the method further comprises:

[0052] A second metal layer is formed on a side of the conductive circuit layer facing away from the diamond layer.

[0053] In some embodiments, the method further comprises:

[0054] The diamond heat sink is cut to form a plurality of sub-heat sinks.

[0055] The present application also provides a diamond heat sink, which includes a diamond heat sink prepared by the above-mentioned method for preparing a diamond heat sink, wherein the method includes:

[0056] providing a substrate comprising a first side and a second side facing each other;

[0057] forming a solder layer on the first side of the substrate;

[0058] Laying a diamond layer on a side of the solder layer facing away from the substrate, wherein the diamond layer includes a plurality of diamonds;

[0059] sintering the substrate, the solder layer, and the diamond layer;

[0060] A conductive circuit layer is provided on a surface of the diamond layer facing away from the solder layer to form a diamond heat sink.

[0061] The method for preparing a diamond heat sink provided in an embodiment of the present application involves sequentially placing a solder layer and a diamond layer on a substrate, sintering the substrate, the solder layer, and the diamond layer, so that the diamond is bonded to the substrate by the solder layer. A conductive circuit layer is then formed on the surface of the diamond facing away from the solder layer to form a diamond heat sink. This method enables the production of small-sized diamonds in a patchwork format, reduces material loss, improves the efficiency of diamond heat sink production, and reduces the cost of diamond heat sink production. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The following detailed description of the specific embodiments of the present application in conjunction with the accompanying drawings will make the technical solutions and other beneficial effects of the present application apparent.

[0063] FIG1 is a flow chart of an embodiment of a method for preparing a diamond heat sink provided in an embodiment of the present application;

[0064] FIG2 is a schematic structural diagram of a method for preparing a diamond heat sink according to an embodiment of the present application after providing a substrate;

[0065] FIG3 is a schematic structural diagram of a diamond heat sink after a solder layer is formed in the method for preparing the diamond heat sink provided in an embodiment of the present application;

[0066] FIG4 is a schematic structural diagram of a diamond heat sink after a diamond layer is formed in the method for preparing the diamond heat sink provided in an embodiment of the present application;

[0067] FIG5 is a schematic structural diagram of the method for preparing a diamond heat sink provided in an embodiment of the present application after the substrate and the first support plate are connected;

[0068] FIG6 is a schematic structural diagram of the diamond heat sink after grinding the surface of the diamond layer facing away from the solder layer in the method for preparing the diamond heat sink provided in an embodiment of the present application;

[0069] FIG7 is a schematic diagram of the structure after forming a seed layer in the method for preparing a diamond heat sink provided in an embodiment of the present application;

[0070] FIG8 is a schematic structural diagram of a diamond heat sink after a conductive circuit layer is formed in the method for preparing the diamond heat sink provided in an embodiment of the present application;

[0071] FIG9 is a schematic structural diagram of a diamond heat sink after forming a first metal layer and a second metal layer in a method for preparing the diamond heat sink provided in an embodiment of the present application;

[0072] FIG10 is a schematic structural diagram of a diamond heat sink after cutting the diamond heat sink into sub-heat sinks in the method for preparing the diamond heat sink provided in an embodiment of the present application;

[0073] FIG11 is a top view of an embodiment of a diamond heat sink provided in an embodiment of the present application;

[0074] FIG12 is an enlarged view of point A in FIG11 .

[0075] Diamond heat sink 200; sub-heat sink 2000; joint seam 2001; substrate 210; first side 211; second side 212; solder layer 220; diamond layer 230; diamond 231; conductive circuit layer 240; seed layer 241; conductive layer 242; second metal layer 243; positive electrode 244; negative electrode 245; first metal layer 250; first support plate 260; second support plate 270. Modes for Carrying Out the Invention

[0076] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0077] The disclosure below provides many different embodiments or examples for realizing different structures of the present application. In order to simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art will appreciate the application of other processes and / or the use of other materials.

[0078] The present invention provides a method for preparing a diamond heat sink and a diamond heat sink, which are described in detail below.

[0079] First, an embodiment of the present application provides a method for preparing a diamond heat sink.

[0080] FIG1 is a flow chart of an embodiment of a method for preparing a diamond heat sink provided in an embodiment of the present application. As shown in FIG1 , the method for preparing a diamond heat sink includes steps S110 to S150, which are described in detail as follows:

[0081] S110 , providing a substrate 210 , wherein the substrate 210 includes a first side surface 211 and a second side surface 212 opposite to each other.

[0082] As shown in FIG2 , the first side surface 211 and the second side surface 212 of the substrate 210 are located on opposite sides of the substrate 210 along the thickness direction of the substrate 210. The substrate 210 may be copper foil. The thickness of the substrate 210 may be greater than or equal to 150 μm and less than or equal to 500 μm. Of course, the substrate 210 may also be made of other metals or non-metals with high thermal conductivity.

[0083] The length and width of the substrate 210 determine the length and width of the resulting diamond heat sink 200. Therefore, the length and width of the substrate 210 can be determined based on the desired size of the diamond heat sink 200. In some embodiments, the length of the substrate 210 is greater than or equal to 100 mm. Alternatively, the width of the substrate 210 is greater than or equal to 100 mm.

[0084] S120 , forming a solder layer 220 on the first side surface 211 of the substrate 210 , as shown in FIG. 3 .

[0085] In some embodiments, the material of the solder layer 220 may be active solder and may be printed on the first side 211 of the substrate 210. Specifically, the solder layer 220 may be printed on the first side 211 of the substrate 210 using a screen printing process.

[0086] S130 , laying a diamond layer 230 on the side of the solder layer 220 facing away from the substrate 210 , where the diamond layer 230 includes a plurality of diamonds 231 .

[0087] As shown in FIG4 , the plurality of diamonds 231 of the diamond layer 230 are laid flat on the surface of the solder layer 220 facing away from the substrate 210. The structure of the diamond 231 can be a sheet structure. The diamond 231 can be a single crystal diamond sheet or a polycrystalline diamond sheet. The thermal conductivity of single crystal diamond can exceed 2000 W / m*K, and the thermal conductivity of polycrystalline diamond can reach 1500 W / m*K. Therefore, when the diamond 231 is a single crystal diamond sheet, the diamond heat sink 200 prepared by the method for preparing the diamond heat sink provided in the embodiment of the present application can have a higher thermal conductivity efficiency.

[0088] S140 , sintering the substrate 210 , the solder layer 220 and the diamond layer 230 .

[0089] The substrate 210 , the solder layer 220 and the diamond layer 230 may be fixed by a fixture and then placed in a sintering furnace for sintering, so that the diamond 231 is bonded to the substrate 210 by the solder layer 220 .

[0090] In some embodiments, the substrate 210, solder layer 220, and diamond layer 230 may be sintered within a first preset temperature range, which is less than or equal to 800° C. The sintering temperature of the substrate 210, solder layer 220, and diamond layer 230 may be 700° C., 750° C., etc., depending on the materials of the solder layer 220 and the substrate 210.

[0091] S150 , disposing a conductive circuit layer 240 on a surface of the diamond layer 230 facing away from the solder layer 220 to form a diamond heat sink 200 .

[0092] As shown in Figures 8, 11 and 12, by providing a conductive circuit layer 240 on the surface of the diamond 231 facing away from the solder layer 220, the conductive circuit layer 240 can be electrically connected to the high-power device mounted on the diamond heat sink 200, thereby electrically connecting the high-power device to other circuits or electronic devices, thereby achieving normal operation of the high-power device.

[0093] The method for preparing a diamond heat sink provided in an embodiment of the present application comprises sequentially placing a solder layer 220 and a diamond layer 230 on a substrate 210, and sintering the substrate 210, the solder layer 220, and the diamond layer 230, so that the diamond 231 is bonded to the substrate 210 by the solder layer 220. Subsequently, a conductive circuit layer 240 is placed on the surface of the diamond 231 facing away from the solder layer 220 to form the diamond heat sink 200. This method enables the production of a panel of small-sized diamonds 231, reduces material loss, improves the production efficiency of the diamond heat sink 200, and reduces the production cost of the diamond heat sink 200.

[0094] In some embodiments, before the conductive circuit layer 240 is provided on the surface of the diamond layer 230 facing away from the solder layer 220 , as shown in FIG5 and FIG6 , the method for preparing the diamond heat sink further includes: grinding and polishing the surface of the diamond layer 230 facing away from the solder layer 220 .

[0095] It is understood that due to the thickness variations of the solder layer 220 and the height variations of the diamonds 231, after sintering the substrate 210 with the solder layer 220 and diamond layer 230, as shown in FIG5 , there are certain height variations of the diamonds 231 at different locations on the diamond layer 230. By grinding and polishing the side of the diamond layer 230 facing away from the solder layer 220, the surface of the diamond layer 230 facing away from the solder layer 220 can be made smoother, facilitating the placement of the conductive circuit layer 240 on the surface of the diamond layer 230 facing away from the solder layer 220.

[0096] In some embodiments, before grinding and polishing the surface of the diamond layer 230 facing away from the solder layer 220, as shown in Figure 5, the method for preparing the diamond heat sink further includes: providing a first support plate 260; and connecting the second side surface 212 of the substrate 210 to a side surface of the first support plate 260.

[0097] By connecting the second side surface 212 of the substrate 210 to one side surface of the first support plate 260, the first support plate 260 can support the substrate 210, thereby preventing the substrate 210 from being deformed during the grinding and polishing process of the side of the diamond layer 230 facing away from the solder layer 220, thereby affecting the grinding effect of the diamond layer 230.

[0098] The first support plate 260 may be a relatively strong plate such as a sapphire plate or a glass plate. The second side surface 212 of the substrate 210 may be bonded to a side surface of the first support plate 260 using an adhesive to provide a more stable connection between the second side surface 212 of the substrate 210 and the side surface of the first support plate 260.

[0099] Of course, when the substrate 210 is thicker or the substrate 210 is stronger, it is not necessary to connect the substrate 210 to the first support plate 260 , but the side of the diamond layer 230 facing away from the solder layer 220 can be directly ground and polished.

[0100] In some embodiments, the step of providing the conductive circuit layer 240 on the surface of the diamond layer 230 facing away from the solder layer 220 may include steps S151 to S153, which are described in detail as follows:

[0101] S151 , as shown in FIG7 , depositing a seed layer 241 on the surface of the diamond layer 230 facing away from the solder layer 220 .

[0102] The seed layer 241 may be formed by physical vapor deposition on the surface of the diamond layer 230 facing away from the solder layer 220. The seed layer 241 may be made of materials such as titanium / copper (Ti / Cu) and chromium / copper (Cr / Cu).

[0103] In some embodiments, before depositing the seed layer 241 on the surface of the diamond layer 230 facing away from the solder layer 220 , as shown in FIG. 6 and FIG. 7 , the method for preparing the diamond heat sink further includes: peeling the substrate 210 from one side of the first support plate 260 .

[0104] It is understood that during the process of depositing the seed layer 241 on the surface of the diamond layer 230 facing away from the solder layer 220, the substrate 210 is in a high-temperature environment, at a temperature of approximately 300°C. This can easily cause adhesion between the second side surface 212 of the substrate 210 and one side surface of the first support plate 260, causing the substrate 210 to separate from the first support plate 260, thereby affecting the seed layer 241 formed by deposition on the surface of the diamond layer 230 facing away from the solder layer 220. By peeling the substrate 210 from the one side surface of the first support plate 260, the effect of the separation of the substrate 210 from the first support plate 260 on the deposition of the seed layer 241 can be avoided.

[0105] In some embodiments, the first support plate 260 may be removed by laser lift-off technology to facilitate separation of the first support plate 260 from the substrate 210 .

[0106] Of course, when the adhesive between the second side surface 212 of the substrate 210 and one side surface of the first support plate 260 can withstand a higher temperature, or when the second side surface 212 of the substrate 210 and one side surface of the first support plate 260 are connected by other means, the first support plate 260 may not be peeled off during the process of depositing the seed layer 241.

[0107] S152 , as shown in FIG8 , forming a conductive layer 242 on a surface of the seed layer 241 facing away from the diamond layer 230 .

[0108] The conductive layer 242 may be made of copper or other metals and may be formed on the side of the seed layer 241 away from the diamond layer 230 by direct copper plating (DPC).

[0109] S153 , etching the conductive layer 242 and the seed layer 241 to form a conductive circuit layer 240 .

[0110] By etching the conductive layer 242 and the seed layer 241, the material of a portion of the conductive layer 242 and the seed layer 241 can be removed, and the unetched portion of the conductive layer 242 and the seed layer 241 forms the conductive circuit layer 240. The conductive layer 242 and the seed layer 241 can be etched by a photolithography and development process to form the conductive circuit layer 240.

[0111] In some embodiments, after etching the conductive layer 242 and the seed layer 241 to form the conductive circuit layer 240, the method for preparing a diamond heat sink further includes grinding the surface of the conductive circuit layer 240 facing away from the diamond layer 230 to achieve a predetermined thickness of the conductive circuit layer 240. After forming the conductive circuit layer 240, grinding the surface of the conductive circuit layer 240 facing away from the diamond layer 230 can achieve the desired thickness of the conductive circuit layer 240.

[0112] In some embodiments, before grinding the surface of the conductive circuit layer 240 facing away from the diamond layer 230 , the method for preparing the diamond heat sink further includes: providing a second support plate 270 ; and connecting the second side surface 212 of the substrate 210 to a side surface of the second support plate 270 .

[0113] By connecting the second side surface 212 of the substrate 210 to one side surface of the second support plate 270, the second support plate 270 can support the substrate 210, thereby preventing the substrate 210 from being deformed during the grinding process of the surface of the conductive circuit layer 240 facing away from the diamond layer 230, thereby affecting the grinding effect of the surface of the conductive circuit layer 240 facing away from the diamond layer 230.

[0114] The second support plate 270 may be a relatively strong plate such as a sapphire plate or a glass plate. The second side surface 212 of the substrate 210 may be bonded to a side surface of the second support plate 270 using an adhesive to provide a more stable connection between the second side surface 212 of the substrate 210 and the side surface of the second support plate 270. The second support plate 270 and the first support plate 260 may be the same support plate or two different support plates.

[0115] Of course, when the substrate 210 is thicker or stronger, it is not necessary to connect the substrate 210 to the second support plate 270 , but the surface of the conductive circuit layer 240 facing away from the diamond layer 230 can be directly ground.

[0116] In some embodiments, the material of the substrate 210 is a metal material. As shown in FIG8 and FIG9, the method for preparing the diamond heat sink further includes steps S160 and S170, which are described in detail as follows:

[0117] S160 , peeling the substrate 210 from one side surface of the second support plate 270 .

[0118] The second support plate 270 may be removed by laser lift-off technology, so that the second support plate 270 and the substrate 210 can be separated more conveniently.

[0119] S170 , forming a first metal layer 250 on the second side surface 212 of the substrate 210 .

[0120] The first metal layer 250 may be formed on the second side surface 212 of the substrate 210 by electroplating. The material of the first metal layer 250 includes nickel / gold (Ni / Au), silver (Ag), etc.

[0121] In some embodiments, the method for preparing the diamond heat sink further includes: forming a second metal layer 243 on a side of the conductive circuit layer 240 facing away from the diamond layer 230 .

[0122] The second metal layer 243 can be formed on the side of the conductive circuit layer 240 facing away from the diamond layer 230 by electroplating. Materials for the second metal layer 243 include nickel / gold (Ni / Au), silver (Ag), and the like. Specifically, the first metal layer 250 and the second metal layer 243 can be formed by electroplating simultaneously on the second side surface 212 of the substrate 210 and the side of the conductive circuit layer 240 facing away from the diamond layer 230.

[0123] In some embodiments, as shown in FIG. 10 , the method for preparing the diamond heat sink further includes: cutting the diamond heat sink 200 to form a plurality of sub-heat sinks 2000 .

[0124] The diamond heat sink 200 can be cut by laser to form a plurality of sub-heat sinks 2000. Each sub-heat sink 2000 can be used to mount a high-power device. Of course, the diamond heat sink 200 can also be cut by other methods to form a plurality of sub-heat sinks 2000.

[0125] In addition, the structures of the sub-heat sinks 2000 may be the same, or the structures of some of the sub-heat sinks 2000 or each of the sub-heat sinks 2000 may be different.

[0126] Specifically, as shown in Figures 10, 11, and 12, the diamond heat sink 200 includes multiple sub-heat sinks 2000. A seam 2001 is formed between two adjacent sub-heat sinks 2000. The diamond heat sink 200 can be cut along the seam 2001 to separate the diamond heat sink 200 into multiple sub-heat sinks 2000. The conductive circuit layer 240 on each sub-heat sink 2000 includes a positive electrode 244 and a negative electrode 245 that are isolated from each other. When a high-power device is mounted on the sub-heat sink 2000, the positive electrode 244 and the negative electrode 245 are electrically connected to the high-power device.

[0127] Of course, when the size of the diamond heat sink 200 is small, high-power devices can also be directly mounted on the diamond heat sink 200 without cutting the diamond heat sink 200 .

[0128] An embodiment of the present application also provides a diamond heat sink, which includes a diamond heat sink prepared by the preparation method of the diamond heat sink in any of the above embodiments. The specific structure of the preparation method of the diamond heat sink refers to the above embodiments. Since the diamond heat sink adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0129] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0130] The above is a detailed introduction to the preparation method of a diamond heat sink and the diamond heat sink provided in the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0131] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0132] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0133] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

Claims

1. A method for preparing a diamond heat sink, wherein: The method comprises: Providing a substrate, wherein the substrate is a copper foil, and the substrate comprises a first side surface and a second side surface opposite to each other; forming a solder layer on the first side of the substrate; Grinding and polishing a surface of the diamond layer that is away from the solder layer; Laying a diamond layer on a side of the solder layer facing away from the substrate, the diamond layer comprising a plurality of diamonds; The substrate, the solder layer and the diamond layer are placed in a first preset temperature range for sintering, and the first preset temperature range is less than or equal to 800° C.; A conductive circuit layer is provided on a surface of the diamond layer facing away from the solder layer to form a diamond heat sink; The diamond heat sink is cut to form a plurality of sub-heat sinks.

2. A method for preparing a diamond heat sink, wherein: The method comprises: providing a substrate, the substrate comprising a first side and a second side opposite to each other; forming a solder layer on the first side of the substrate; Laying a diamond layer on a side of the solder layer facing away from the substrate, the diamond layer comprising a plurality of diamonds; Sintering the substrate, the solder layer and the diamond layer; A conductive circuit layer is arranged on a surface of the diamond layer facing away from the solder layer to form a diamond heat sink.

3. The method for preparing a diamond heat sink according to claim 2, wherein: The sintering of the substrate, the solder layer and the diamond layer comprises: The substrate, the solder layer and the diamond layer are placed in a first preset temperature range for sintering, and the first preset temperature range is less than or equal to 800°C.

4. The method for preparing a diamond heat sink according to claim 3, wherein: Before sintering the substrate, the solder layer and the diamond layer, the method further includes: The substrate, solder layer and diamond layer are fixed by a clamp.

5. The method for preparing a diamond heat sink according to claim 2, wherein: Before providing a conductive circuit layer on a surface of the diamond layer facing away from the solder layer, the method further comprises: The surface of the diamond layer facing away from the solder layer is ground and polished.

6. The method for preparing a diamond heat sink according to claim 5, wherein: Before grinding and polishing the surface of the diamond layer facing away from the solder layer, the method further comprises: providing a first support plate; The second side surface of the substrate is connected to a side surface of the first supporting plate.

7. The method for preparing a diamond heat sink according to claim 6, wherein: The step of connecting the second side surface of the substrate to a side surface of the first support plate comprises: The second side surface of the substrate is bonded to one side surface of the first support plate by an adhesive.

8. The method for preparing a diamond heat sink according to claim 6, wherein: The first supporting plate is a sapphire plate or a glass plate.

9. The method for preparing a diamond heat sink according to claim 2, wherein: The thickness of the substrate is greater than or equal to 150 μm and less than or equal to 500 μm; The length of the substrate is greater than or equal to 100 mm; Alternatively, the width of the substrate 210 is greater than or equal to 100 mm.

10. The method for preparing a diamond heat sink according to any one of claims 2 to 9, wherein: The step of providing a conductive circuit layer on a surface of the diamond layer facing away from the solder layer comprises: Depositing a seed layer on a surface of the diamond layer facing away from the solder layer; forming a conductive layer on a surface of the seed layer facing away from the diamond layer; The conductive layer and the seed layer are etched to form the conductive circuit layer.

11. The method for preparing a diamond heat sink according to claim 10, wherein: The material of the seed layer includes titanium / copper and chromium / copper.

12. The method for preparing a diamond heat sink according to claim 10, wherein: After etching the conductive layer and the seed layer to form the conductive circuit layer, the method further includes: The surface of the conductive circuit layer facing away from the diamond layer is ground so that the thickness of the conductive circuit layer reaches a preset thickness.

13. The method for preparing a diamond heat sink according to claim 12, wherein: Before grinding the surface of the conductive circuit layer facing away from the diamond layer, the method further comprises: providing a second support plate; The second side surface of the substrate is connected to a side surface of the second supporting plate.

14. The method for preparing a diamond heat sink according to claim 13, wherein: The second supporting plate is a sapphire plate or a glass plate.

15. The method for preparing a diamond heat sink according to claim 13, wherein: The step of connecting the second side surface of the substrate to a side surface of the second support plate comprises: The second side surface of the substrate is bonded to one side surface of the second support plate by an adhesive.

16. The method for preparing a diamond heat sink according to claim 13, wherein: The material of the substrate is a metal material; the method further comprises: Peeling the substrate off one side surface of the second supporting plate; A first metal layer is formed on the second side of the substrate.

17. The method for preparing a diamond heat sink according to claim 16, wherein: The material of the first metal layer includes nickel / gold and silver.

18. The method for preparing a diamond heat sink according to claim 12, wherein: The method further comprises: A second metal layer is formed on a side of the conductive circuit layer away from the diamond layer.

19. The method for preparing a diamond heat sink according to claim 2, wherein: The method further comprises: The diamond heat sink is cut to form a plurality of sub-heat sinks.

20. A diamond heat sink, wherein: The diamond heat sink comprises a diamond heat sink prepared by the method for preparing a diamond heat sink according to any one of claims 1 to 19.

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