Preparation method of heat dissipation structure and semiconductor device

Abstract

The invention provides a preparation method of a heat dissipation structure and a semiconductor device, and the method comprises the steps: providing a wafer, and dividing the wafer into a wafer unit array; placing the wafer unit array in deposition equipment, and growing a heat dissipation layer on the surface of each wafer unit in the wafer unit array through a heteroepitaxial process; and carrying out planarization processing on the surface of the heat dissipation layer. The three-dimensional surrounding and wrapping heat dissipation layer is formed on the surface of the wafer unit, so that the heat dissipation effect of the device is greatly improved, the service life of the device is prolonged, and the working stability of the device is improved.

Description

Technical Field

[0001] The present application relates to the technical field of heat dissipation, and particularly relates to a preparation method of a heat dissipation structure and a semiconductor device. Background Art

[0002] Due to the limitations of the material properties of silicon-based power electronic devices, they can no longer meet the high-performance requirements of semiconductor devices in today's power electronics field. Based on this, wide-bandgap semiconductor materials represented by silicon carbide (SiC) have emerged. Compared with silicon (Si) devices, SiC devices have lower on-resistance, faster switching speed, higher breakdown voltage, and thermal conductivity, etc. These excellent characteristics make SiC devices have significant advantages in high frequency and high power density.

[0003] With the development of system miniaturization, it is necessary to further improve the power density of SiC devices. However, when SiC devices work, they will generate a certain amount of power dissipation, and this part of the power dissipation will generate a large amount of heat inside the device, especially at the conductive channel, which will cause a significant increase in the device junction temperature, greatly strengthen the lattice vibration scattering, reduce the electron mobility in the drift region, and cause a significant increase in the device on-resistance. This phenomenon is called the "self-heating effect". Especially after the SiC-based HEMT (high electron mobility transistor) device is stored at 200 °C for 300 hours, its saturation current decreases by about 10%, and its maximum transconductance decreases by about 6%. Therefore, the heat dissipation problem is becoming more and more important. How to achieve effective heat dissipation to weaken the influence of the self-heating effect has become a challenge for high-power density SiC power devices to maintain high reliability and long life.

[0004] It should be noted that the information disclosed in the above background art section is only used to strengthen the understanding of the background of the present application, and therefore may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Invention

[0005] Aiming at the problems in the prior art, the purpose of the present application is to provide a preparation method of a heat dissipation structure and a semiconductor device, which form a three-dimensional surrounding heat dissipation layer on the surface of the wafer unit, greatly improve the heat exchange efficiency of the device, and enhance the stability and life of the device.

[0006] An embodiment of the present application provides a preparation method of a heat dissipation structure, including:

[0007] Providing a wafer, and dividing the wafer into a wafer unit array;

[0008] Placing the wafer unit array in a deposition device, and growing a heat dissipation layer on the surface of each wafer unit in the wafer unit array by heteroepitaxy process;

[0009] Performing a planarization treatment on the surface of the heat dissipation layer.

[0010] In some embodiments, dividing the wafer into a wafer unit array includes the following steps:

[0011] Dividing the wafer into multiple wafer units by laser;

[0012] Arranging the wafer units in an array form, and the distance between two adjacent wafer units is less than 400 μm.

[0013] In some embodiments, before arranging the wafer units in an array form, it further includes: polishing and cleaning each of the wafer units.

[0014] In some embodiments, the deposition device is a microwave plasma chemical vapor deposition device.

[0015] In some embodiments, the heat dissipation layer is a diamond heat dissipation layer.

[0016] In some embodiments, when growing a diamond heat dissipation layer on the surface of each wafer unit in the wafer unit array by heteroepitaxial process, controlling the volume flow ratio of methane, hydrogen, and oxygen to be 35:800:5, the growth temperature is 900 - 1000 °C, the pressure is 100 - 150 torr, and the growth time is 60 - 80 hours.

[0017] In some embodiments, performing planarization treatment on the surface of the heat dissipation layer includes the following steps:

[0018] Performing planarization treatment on the surface of the diamond heat dissipation layer by diamond mechanical grinding.

[0019] In some embodiments, when growing a heat dissipation layer on the surface of each wafer unit in the wafer unit array by heteroepitaxial process, the heat dissipation layer is formed on the first side surface and the side surface of each wafer unit respectively.

[0020] In some embodiments, after performing planarization treatment on the surface of the heat dissipation layer, it further includes the following steps:

[0021] Polishing and cleaning the second side surface of the wafer unit, and the second side surface and the first side surface are oppositely arranged along the thickness direction of the wafer.

[0022] The embodiments of the present application further provide a semiconductor device, and the substrate of the semiconductor device is prepared by using the preparation method of the heat dissipation structure described above.

[0023] The preparation method of the heat dissipation structure and the semiconductor device provided by the present application have the following advantages:

[0024] By adopting the present application, a three-dimensionally surrounded heat dissipation layer is formed on the surface of the wafer unit, increasing the heat dissipation area of the device in contact with the heat dissipation layer, greatly improving the heat exchange efficiency and heat dissipation performance of the device, significantly enhancing the heat dissipation effect of the device, reducing the channel temperature of the device, increasing the working power density of the device, and effectively improving the stability and lifespan of the device during use. Description of the Drawings

[0025] The drawings herein are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present invention, and are used together with the specification to explain the principles of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can obtain other drawings based on these drawings without creative efforts.

[0026] Figure 1 is a flowchart of a method for preparing a heat dissipation structure according to an embodiment of the present application;

[0027] Figure 2 is a top view of dividing the wafer into a wafer unit array according to an embodiment of the present application;

[0028] Figure 3 is a cross-sectional view of the wafer unit array spliced and arranged according to an embodiment of the present application;

[0029] Figure 4 is a cross-sectional view of growing a heat dissipation layer on the surface of the wafer unit according to an embodiment of the present application;

[0030] Figure 5 is a cross-sectional view of polishing and grinding the heat dissipation layer according to an embodiment of the present application;

[0031] Figure 6 is a cross-sectional view of turning over, polishing, and cleaning the wafer unit according to an embodiment of the present application;

[0032] Figure 7 is a cross-sectional view of using the wafer unit as an active region according to an embodiment of the present application. Detailed Description of the Invention

[0033] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. Like reference numerals in the figures denote like or similar structures and thus their repetitive description will be omitted. As used in the specification, "or" and "or" may both mean "and" or "or". Spatial relationship terms such as "on..." can be used herein to describe the relationship of one element or feature shown in the figure with other elements or features. It should be understood that, in addition to the orientation shown in the figures, spatial relationship terms also include different orientations of the device during use and operation. For example, if the device in the figure is flipped, the element or feature described as "on..." will be oriented "under..." other elements or features. Therefore, the exemplary term "on..." can include both the upper and lower orientations. In addition, the device may also include other orientations (such as rotating 90 degrees or other orientations), and the spatial description used herein is accordingly interpreted.

[0034] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that when the terms "comprise" and / or "include" are used in this specification, the presence of the stated features, integers, steps, operations, elements and / or components can be determined, but one or more other features, integers, steps, operations, elements, components and / or groups are not excluded from the presence or addition. At the same time, as used herein, the term "and / or" includes any and all combinations of the related listed items. Although terms such as "first" or "second" are used in this specification to denote certain features, they are only for representational purposes and do not limit the quantity and importance of the specific features.

[0035] Today's electronic devices are advancing rapidly towards high integration and high power density. This development trend has led to a sharp increase in the heat generated during the operation of the devices, and the heat dissipation problem has become a key bottleneck restricting the improvement of device performance, stability guarantee, and service life extension. The research and application of efficient heat dissipation structures are of crucial strategic significance for solving the heat dissipation problems of electronic devices and promoting the sustainable development of the electronics industry. The heat dissipation structure preparation method proposed in the embodiments of this application is precisely designed to address this challenge and aims to create an efficient three-dimensional surrounding heat dissipation structure for various electronic devices through unique process steps, thereby significantly improving the heat dissipation effect. The embodiments of this application also provide a semiconductor device, the substrate of which is prepared by using the heat dissipation structure preparation method described above, and this semiconductor device has better heat dissipation performance, higher stability, and longer service life.

[0036] As Figure 1As shown, an embodiment of the present application provides a method for preparing a heat dissipation structure, including:

[0037] S100: Provide a wafer and divide the wafer into a wafer unit array;

[0038] This wafer is, for example, a silicon carbide wafer, a silicon wafer, etc.; silicon carbide (SiC), as a wide-bandgap semiconductor material, has many excellent physical and chemical properties. It has a large bandgap and can withstand a higher electric field strength, thus performing excellently in high-power and high-frequency applications. In addition, silicon carbide also has advantages such as a high breakdown electric field, a high electron mobility, and good thermal conductivity, enabling devices fabricated based on silicon carbide wafers to operate stably in high-temperature, high-pressure, and high-frequency environments. For example, in the power electronics system of electric vehicles, silicon carbide devices can significantly improve the efficiency and power density of the system; while silicon wafers dominate in fields such as large-scale integrated circuits due to their mature manufacturing processes and lower costs;

[0039] In this embodiment, the wafer is divided into multiple wafer units by laser cutting technology. By precisely controlling the energy, pulse frequency, and scanning speed of the laser, the size of each wafer unit can be precisely controlled;

[0040] S200: Place the wafer unit array in a deposition device and grow a heat dissipation layer on the surface of each wafer unit in the wafer unit array through heteroepitaxial technology;

[0041] Since the wafer is pre-divided into multiple wafer units and the multiple wafer units are arranged in an array, when forming the heat dissipation layer, not only can a heat dissipation layer be formed on one side surface of the wafer, but also a heat dissipation layer can be formed on the side surface of the wafer, forming a heat dissipation structure that three-dimensionally surrounds and wraps the wafer;

[0042] Among them, when growing the heat dissipation layer on the surface of each wafer unit in the wafer unit array through heteroepitaxial technology, the heat dissipation layer is formed on the first side surface and the side surface of each wafer unit respectively;

[0043] S300: Perform planarization processing on the surface of the heat dissipation layer;

[0044] Since the surface of the heat dissipation layer obtained in step S200 is relatively rough, by performing planarization processing on the surface of the heat dissipation layer, the surface of the heat dissipation layer becomes smoother for subsequent processing.

[0045] By adopting the method for preparing the heat dissipation structure of the present application, a three-dimensionally surrounding and wrapping heat dissipation layer is formed on the surface of the wafer unit, increasing the heat dissipation area in contact between the device and the heat dissipation layer, greatly improving the heat transfer efficiency and heat dissipation performance of the device, significantly improving the heat dissipation effect of the device, reducing the channel temperature of the device, increasing the working power density of the device, and effectively enhancing the stability and service life of the device.

[0046] The preparation method of this heat dissipation structure can be applied to silicon carbide-based devices, and can also be used in the preparation process of silicon-based devices, GaN (gallium nitride)-based devices, or diamond-based devices, or other device structures that require heat dissipation. The following takes the application of this heat dissipation structure to silicon carbide power devices as an example for illustration. In the future development of electronic devices, with the continuous increase in power density, this efficient heat dissipation structure will play an increasingly important role.

[0047] In this embodiment, in step S100, dividing the wafer into a wafer unit array includes the following steps:

[0048] Dividing the wafer into multiple wafer units by laser; the size of the obtained wafer units is the same as the size of the product chip. For example, the surface size of the wafer unit is 1500μm×1200μm;

[0049] Polishing and cleaning each of the wafer units to remove the surface damage and roughness generated during the cutting process, so that the surface of the wafer unit reaches extremely high flatness; the polishing methods used are, for example, mechanical polishing, chemical mechanical polishing (CMP), etc.;

[0050] Arranging the wafer units in an array form, and the distance between two adjacent wafer units is less than 400μm, forming a high-density wafer unit array structure. This closely arranged structure can not only make full use of the space of the deposition equipment to improve production efficiency, but also enable the side surfaces of each wafer unit to effectively form a heat dissipation layer during the subsequent growth of the heat dissipation layer, thereby realizing a three-dimensional surrounding and wrapping of the wafer. During the arrangement process, in order to ensure the accuracy of the array arrangement, for example, a high-precision positioning and fixing device can be used to assist the arrangement.

[0051] In this embodiment, the heat dissipation layer is a diamond heat dissipation layer. Diamond is the material with the highest thermal conductivity among bulk materials. The thermal conductivity of single-crystal diamond is as high as 2400W / (m·K) at room temperature, and the thermal conductivity of polycrystalline diamond also reaches 2000W / (m·K), which is much higher than the thermal conductivity of other commonly used silicon carbide substrate materials and is an ideal heat dissipation material. By integrating diamond with high thermal conductivity with silicon carbide power devices, due to the ultra-high thermal conductivity of diamond, the heat generated by the heat source will quickly diffuse laterally in the substrate, increasing the effective heat exchange area between the heat source and the outside world, thereby greatly improving the heat exchange capacity of the system, significantly enhancing the heat dissipation effect of silicon carbide power devices, reducing the channel temperature of the devices, and thus increasing the working power density of silicon carbide power devices.

[0052] In this embodiment, the deposition device is a microwave plasma chemical vapor deposition device (MPCVD). The microwave plasma chemical vapor deposition device forms plasma by microwave-exciting reaction gases and deposits high-quality thin film materials on the surface of the substrate. Its working principle is that microwave energy is introduced into the reaction chamber through a waveguide to ionize gas molecules to form plasma. The active particles in the plasma adsorb, migrate and undergo chemical reactions on the surface of the substrate to form the target thin film. When forming the diamond heat dissipation layer, a DC bias voltage is applied between the substrate and the anode to induce the directional formation of diamond nuclei. After turning off the bias voltage, the plasma continuously supplies carbon, and the nuclei grow epitaxially along the crystal orientation of the silicon carbide wafer unit to form a single-crystal diamond layer. In step S200, when growing the diamond heat dissipation layer on the surface of each wafer unit in the wafer unit array by heteroepitaxy process, the volume flow ratio of methane, hydrogen and oxygen is controlled to be 35:800:5, the growth temperature is 900 - 1000 °C, the pressure is 100 - 150 torr, and the growth time is 60 - 80 hours. During the growth process, methane serves as a carbon source to provide carbon atoms for the growth of diamond. As a carbon source, the flow rate of methane directly affects the growth rate and quality of diamond. When the methane flow rate is too low, the number of provided carbon atoms is insufficient and the growth rate is slow; when the methane flow rate is too high, the formation of non-diamond phase carbon will increase, reducing the purity and quality of diamond. Therefore, it is necessary to precisely control the flow rate of methane according to specific process requirements. Hydrogen decomposes in the plasma to produce hydrogen atoms, which have the function of etching non-diamond phase carbon and helps to improve the purity and quality of diamond. The hydrogen atoms generated by the decomposition of hydrogen in the plasma play an important role in the growth of diamond. The flow rate of hydrogen will affect the concentration of hydrogen atoms and the properties of the plasma. Appropriately increasing the hydrogen flow rate can increase the concentration of hydrogen atoms and enhance the ability to etch non-diamond phase carbon, thereby improving the purity and quality of diamond. However, too high a hydrogen flow rate will also lead to a decrease in the growth rate, and a balance needs to be achieved between the two. The addition of oxygen can inhibit the formation of non-diamond phases such as graphite and improve the growth quality of diamond. The flow rate of oxygen needs to be optimized according to specific process conditions. Too high an oxygen flow rate will lead to a decrease in the growth rate of diamond and may even corrode the substrate material. Each of these process parameters here is only an example and not a limitation of the protection scope of this application. In practical applications, different process parameters can be selected according to different device types, different wafer types, and different heat dissipation layer materials, and all such variations fall within the protection scope of this application.

[0053] In this embodiment, in step S300, planarizing the surface of the heat dissipation layer includes: planarizing the surface of the diamond heat dissipation layer by diamond mechanical grinding. After the single-crystal diamond epitaxy is completed, there are often some protrusions, uneven areas, and surface defects on the surface of the heat dissipation layer. Diamond mechanical grinding utilizes the high hardness and wear resistance of diamond abrasives to precisely grind and polish the surface of the heat dissipation layer. By controlling parameters such as the grinding pressure, grinding speed, and grinding time, the uneven areas on the surface can be removed, making the surface of the diamond heat dissipation layer reach a certain flatness, providing a good foundation for subsequent further processing or cooperation with other components. During the grinding process, the thickness of the diamond heat dissipation layer can be appropriately adjusted according to actual needs to ensure that its thickness is uniform and meets the design requirements, thereby better realizing the heat dissipation function. A uniform thickness is crucial for achieving good heat dissipation performance, which can ensure uniform heat transfer throughout the heat dissipation layer and avoid local overheating problems. Grinding can improve the micro-structure of the surface of the diamond heat dissipation layer, reduce surface defects, etc., which helps to improve its thermal conductivity and the interfacial bonding performance with other materials.

[0054] In this embodiment, after step S300: planarizing the surface of the heat dissipation layer, the following steps are further included:

[0055] Polishing and cleaning the second side surface of the wafer unit to remove impurities and oxide layers on the surface, so that the surface reaches a certain smoothness. The second side surface and the first side surface are oppositely arranged along the thickness direction of the wafer. Finally, a structure is formed in which the active region of the silicon carbide substrate is wrapped by the side and bottom of the heat dissipation layer, greatly increasing the heat dissipation area of the silicon carbide power device in contact with the diamond.

[0056] The following combines Figures 2 to 7 Specifically introduce the process of the preparation method of the heat dissipation structure in a specific example. It can be understood that the structures shown in the drawings and the following descriptions are only examples and do not limit the protection scope of this application.

[0057] As Figure 2 and Figure 3As shown, corresponding to step S100, a silicon carbide wafer is provided. After cleaning, the cleaned single-crystal silicon carbide wafer 100 is laser-cut to obtain a plurality of wafer units 10. Laser cutting has the advantages of high precision, high speed, and little damage to the material. During the cutting process, parameters such as the energy, pulse frequency, and scanning speed of the laser are precisely controlled to ensure that the size of the wafer units obtained by cutting is consistent with the size of the product chip. For example, the wafer is cut into wafer units with a surface size of 1500μm × 1200μm. The cut wafer units are polished and cleaned. For example, each wafer unit is finely polished to remove the surface damage and roughness generated during the cutting process, so that the surface of the wafer unit reaches extremely high flatness. Subsequently, a variety of chemical reagents and cleaning processes are used to thoroughly clean the wafer units to remove contaminants such as impurities, oil, and particles on the surface, providing a clean and flat surface for subsequent epitaxial growth. Then, the wafer units 10 are closely arranged in an array, and the gap of the array arrangement is controlled to be less than 400μm to form a high-density wafer unit array structure. This close arrangement method can not only make full use of space, but also enable the side surfaces of each wafer unit to effectively form a heat dissipation layer when growing the heat dissipation layer subsequently, thus realizing a three-dimensional surrounding and wrapping of the wafer.

[0058] As Figure 4 shown, corresponding to step S200, the silicon carbide wafer array is placed in a microwave plasma chemical vapor deposition device for single-crystal diamond heteroepitaxial growth to form a diamond heat dissipation layer 20. The microwave plasma chemical vapor deposition device forms plasma by microwave-exciting reaction gases, and has the advantages of high plasma density, strong activity, and relatively low deposition temperature, and can deposit high-quality thin film materials on the substrate surface. Its working principle is: microwave energy is efficiently introduced into the reaction chamber through a waveguide, ionizing gas molecules in the reaction chamber to form a plasma containing active particles such as electrons, ions, and free radicals. These active particles adsorb, migrate, and chemically react on the substrate surface to form the target thin film. The process parameters during heteroepitaxial growth in the deposition device are: the volume flow rate (sccm) ratio of methane, hydrogen, and oxygen is 35:800:5, the growth temperature is 900 - 1000°C, the pressure is 100 - 150 torr, and the growth time is 60 - 80 hours. Through single-crystal diamond heteroepitaxial growth, a diamond heat dissipation layer is formed on the first surface ( Figure 3 the upper surface) and the side surfaces of each wafer unit. During the growth process of the diamond heat dissipation layer, methane serves as a carbon source to provide carbon atoms for the growth of diamond; hydrogen decomposes in the plasma to produce hydrogen atoms, and hydrogen atoms have the function of etching non-diamond phase carbon, which helps to improve the purity and quality of diamond; oxygen can further inhibit the formation of non-diamond phases such as graphite and optimize the growth environment of diamond.

[0059] AsFigure 5 As shown, corresponding to step S300, after the growth of the diamond heat dissipation layer is completed, there are often some protrusions, uneven areas and surface defects on the surface of the heat dissipation layer. Diamond mechanical grinding is used to planarize the diamond heat dissipation layer so that the diamond heat dissipation layer has a flat surface. Diamond mechanical grinding utilizes the high hardness and wear resistance of diamond abrasives to precisely grind and polish the surface of the heat dissipation layer. By controlling parameters such as grinding pressure, grinding speed and grinding time, the uneven areas on the surface can be removed, and the surface of the diamond heat dissipation layer can reach a certain flatness. The planarized diamond heat dissipation layer is denoted by 30.

[0060] As Figure 6 shown, after the diamond heat dissipation layer 30 is planarized, the overall structure formed by the wafer unit array and the diamond heat dissipation layer 30 is turned over so that the second surface ( Figure 6 the upper surface in Figure 6 the figure) of the wafer unit faces upward and the first surface ( Figure 7 the lower surface in the figure) faces downward. The second surface is polished and cleaned to remove surface impurities and oxide layers, so that the surface reaches a certain smoothness. Finally, the structure shown in

[0061] is formed, in which the active region of the silicon carbide substrate is wrapped by the side and bottom of the diamond heat dissipation layer, greatly increasing the heat dissipation area of the silicon carbide power device in contact with the diamond.

[0062] In summary, the preparation method of the heat dissipation structure and the semiconductor device provided by the present application have the following advantages:

[0063] The above content is a further detailed description of the present application in combination with specific preferred embodiments. It cannot be determined that the specific implementation of the present application is only limited to these descriptions. For those of ordinary skill in the technical field to which the present application belongs, without departing from the concept of the present application, several simple deductions or substitutions can still be made, and all should be regarded as belonging to the protection scope of the present application.

Claims

1. A method for preparing a heat dissipation structure, characterized in that: include: Providing a wafer, and dividing the wafer into wafer unit arrays; Placing the wafer unit array in a deposition device, and growing a heat dissipation layer on the surface of each wafer unit in the wafer unit array by a heteroepitaxial process; The surface of the heat dissipation layer is planarized.

2. The method for preparing the heat dissipation structure according to claim 1, characterized in that: Dividing the wafer into wafer unit arrays comprises the following steps: Dividing the wafer into a plurality of wafer units by laser; The wafer units are arranged in an array, and the distance between two adjacent wafer units is less than 400 μm.

3. The method for preparing the heat dissipation structure according to claim 2, characterized in that: Before arranging the wafer units in an array form, the method further includes: polishing and cleaning each of the wafer units.

4. The method for preparing the heat dissipation structure according to claim 1, characterized in that: The deposition equipment is a microwave plasma chemical vapor deposition equipment.

5. The method for preparing the heat dissipation structure according to claim 1, characterized in that: The heat dissipation layer is a diamond heat dissipation layer.

6. The method for preparing the heat dissipation structure according to claim 5, characterized in that: When the diamond heat dissipation layer is grown on the surface of each wafer unit in the wafer unit array by the heteroepitaxial process, the volume flow ratio of methane, hydrogen and oxygen is controlled to be 35:800:5, the growth temperature is 900-1000°C, the pressure is 100-150torr, and the growth time is 60-80 hours.

7. The method for preparing the heat dissipation structure according to claim 5, characterized in that: The surface of the heat dissipation layer is planarized, comprising the following steps: The surface of the diamond heat dissipation layer is planarized by diamond mechanical grinding.

8. The method for preparing the heat dissipation structure according to claim 1, characterized in that: When a heat dissipation layer is grown on the surface of each wafer unit in the wafer unit array by a heteroepitaxial process, the heat dissipation layer is formed on the first side surface and the side surface of each wafer unit respectively.

9. The method for preparing the heat dissipation structure according to claim 8, characterized in that: After the surface of the heat dissipation layer is planarized, the following steps are also included: The second side surface of the wafer unit is polished and cleaned, and the second side surface and the first side surface are arranged opposite to each other along the thickness direction of the wafer.

10. A semiconductor device, characterized in that: The substrate of the semiconductor device is prepared by the method for preparing a heat dissipation structure according to any one of claims 1 to 9.

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