Thin liquid film nucleate boiling phase change cooling structure and method of manufacture

Abstract

The embodiment of the present application provides a thin liquid film nucleate boiling phase change cooling structure and a manufacturing method thereof, which comprises: forming a boiling cavity structure on a first substrate; etching a second substrate from a first surface of the second substrate to form a plurality of grooves; etching the second substrate from a second surface of the second substrate to the grooves to form a plurality of channels; forming a nano needle structure on the first surface; modifying the nano needle structure by using a surface hydrophobic silane coupling agent to form a super-hydrophobic nano needle surface structure; and combining the boiling cavity structure and the super-hydrophobic porous silicon membrane structure, so that a liquid film can be formed between the boiling cavity structure and the super-hydrophobic porous silicon membrane structure, and the super-hydrophobic porous silicon membrane structure is used to realize bubble separation from the liquid film and discharge. By manufacturing the channels included in the super-hydrophobic porous silicon membrane structure and the super-hydrophobic nano needle surface structure, the gas-liquid separation efficiency can be greatly improved.

Description

Technical Field

[0001] This invention relates to the field of semiconductors, and in particular to a thin liquid film nucleus boiling phase change cooling structure and its manufacturing method. Background Technology

[0002] With the rapid development of semiconductor and related technologies, the demand for heat dissipation for semiconductor chips is also increasing.

[0003] Thin-film nucleoboiling heat transfer technology can form a novel phase change heat transfer mechanism with flow boiling characteristics within a very thin liquid film with the aid of a pump, thus producing extremely high heat transfer efficiency. It is an important way to solve the problem of heat dissipation with ultra-high heat flux density in the future.

[0004] Therefore, there is a need for thin-film nucleo-boiling phase change cooling structures for heat dissipation of semiconductor chips. Summary of the Invention

[0005] In view of this, the purpose of this application is to provide a thin liquid film nucleus boiling phase change cooling structure and its manufacturing method, which can meet the heat dissipation requirements of semiconductor chips.

[0006] To achieve the above objectives, this application provides the following technical solution:

[0007] This application provides a method for manufacturing a thin liquid film nucleus boiling phase change cooling structure, including:

[0008] A boiling chamber structure is formed on the first substrate;

[0009] A plurality of grooves are formed by etching the second substrate of a first thickness from the first surface of the second substrate;

[0010] A second substrate of a second thickness is etched from the second surface of the second substrate to the groove to form a plurality of channels, wherein the thickness of the second substrate is the sum of the first thickness and the second thickness;

[0011] A nanoneedle-like structure is formed on the first surface, and the nanoneedle-like structure is modified with a surface hydrophobic silane coupling agent to form an ultra-hydrophobic nanoneedle-like surface structure; the ultra-hydrophobic nanoneedle-like surface structure and the pores constitute an ultra-hydrophobic porous silicon film structure;

[0012] Combining the boiling chamber structure and the ultra-porous silicon film structure, the ultra-porous nanoneedle-like surface structure faces the boiling chamber structure.

[0013] Optionally, the nanoneedle structure includes a copper hydroxide nanoneedle structure and a copper oxide nanoneedle structure;

[0014] The step of forming a nanoneedle-like structure on the first surface and modifying the nanoneedle-like structure with a surface hydrophobic silane coupling agent to form an ultrahydrophobic nanoneedle-like surface structure includes:

[0015] The copper hydroxide nanoneedle structure is formed on the first surface by electrochemical deposition of copper hydroxide. The copper hydroxide nanoneedle structure is heated in air to form the copper oxide nanoneedle structure. The copper oxide nanoneedle structure is modified with a surface hydrophobic silane coupling agent to form an ultrahydrophobic nanoneedle surface structure.

[0016] Optionally, before forming the copper hydroxide nanoneedle structure on the first surface using electrochemical deposition of copper hydroxide, the method further includes:

[0017] A metal layer is formed on the first surface, wherein the metal layer is a stack of titanium and copper layers.

[0018] Optionally, before etching a second thickness of the second substrate from the second surface of the second substrate to the groove, the method further includes:

[0019] A first protective layer is formed on the sidewall of the groove, the first protective layer being used to assist the growth of the hydrophobic silane coupling agent;

[0020] When modifying the nanoneedle-like structure with a surface-hydrophobic silane coupling agent to form an ultrahydrophobic nanoneedle-like surface structure, the method further includes:

[0021] The hydrophobic silane coupling agent is grown on the surface of the first protective layer.

[0022] Optionally, the material of the first protective layer is silicon oxide.

[0023] Optionally, forming the boiling chamber structure on the first substrate includes:

[0024] The first substrate is etched to form a boiling chamber, and a micropillar structure array is formed at the bottom of the boiling chamber;

[0025] A superhydrophilic coating is grown on the micropillar structure array.

[0026] Optionally, the structural parameters of the pores include pore diameter, porosity, and pore length. The waterproofness and breathability of the ultra-porous silicon membrane structure can be adjusted by adjusting the structural parameters of the pores.

[0027] Optionally, the structural parameters of the nanoneedle structure include needle density, needle diameter, and needle length, and the hydrophobicity of the ultraporous silicon film structure can be adjusted by adjusting the structural parameters of the nanoneedle structure.

[0028] Optionally, the method further includes:

[0029] Forming a metal manifold structure;

[0030] Combining the metal manifold structure and the ultra-porous silicon film structure, the ultra-porous nanoneedle-like surface structure is located away from the metal manifold structure.

[0031] This application provides a thin liquid film nucleus boiling phase change cooling structure, including:

[0032] A boiling chamber structure and an ultra-porous silicon film structure are stacked sequentially.

[0033] The ultra-porous silicon film structure includes an ultra-porous nanoneedle-like surface structure and channels, with the ultra-porous nanoneedle-like surface structure facing the boiling chamber structure;

[0034] A liquid film is formed between the boiling chamber structure and the ultra-porous silicon film structure. The liquid film undergoes a phase change to generate bubbles. The ultra-porous nanoneedle-like surface structure is used to induce the bubbles to detach from the liquid film.

[0035] This application provides a method for manufacturing a thin-film nucleus boiling phase change cooling structure, comprising: forming a boiling cavity structure on a first substrate to form a heat transfer surface of the thin-film nucleus boiling phase change cooling structure; etching a second substrate of a first thickness from a first surface of a second substrate to form a plurality of grooves, i.e., etching grooves from the first surface into the second substrate; etching a second substrate of a second thickness from the second surface of the second substrate to the grooves to form a plurality of channels, i.e., etching from the second surface so that the grooves form channels penetrating a portion of the thickness of the second substrate, wherein the thickness of the second substrate is the sum of the first thickness and the second thickness, thus forming channels by etching two sides of the second substrate, which can be used for gas exhaust; forming a nanoneedle-like structure on the first surface, and modifying the nanoneedle-like structure with a surface hydrophobic silane coupling agent to form an ultra-hydrophobic nanoneedle-like surface structure, which can be used to induce bubbles to detach from the liquid film, thereby increasing the bubble collapse rate and improving the heat transfer coefficient. The ultra-sparse nanoneedle-like surface structure and channels constitute an ultra-sparse porous silicon film structure. Combined with the boiling chamber structure and the ultra-sparse porous silicon film structure, with the ultra-sparse nanoneedle-like surface structure facing the boiling chamber structure, a liquid film can be formed between the boiling chamber structure and the ultra-sparse porous silicon film structure. Furthermore, the ultra-sparse porous silicon film structure facilitates the detachment and discharge of bubbles from the liquid film. Therefore, this application provides a method for manufacturing an ultra-sparse porous silicon film structure that influences gas-liquid separation efficiency. By manufacturing the channels and ultra-sparse nanoneedle-like surface structure included in the ultra-sparse porous silicon film structure, the gas-liquid separation efficiency can be greatly improved, enabling its application in the field of semiconductor chip packaging heat dissipation to meet the heat dissipation requirements of semiconductor chips. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This illustration shows a cross-sectional schematic diagram of a thin liquid film nucleus boiling phase change cooling structure provided in an embodiment of this application;

[0038] Figure 2 This illustration shows a partial cross-sectional schematic diagram of an ultraporous silicon film structure provided in an embodiment of this application;

[0039] Figure 3 A schematic flowchart of a method for manufacturing a thin liquid film nucleus boiling phase change cooling structure according to an embodiment of this application is shown;

[0040] Figures 4-11 This illustration shows a schematic diagram of a thin liquid film nucleus boiling phase change cooling structure provided in an embodiment of this application. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0042] This application is described in detail with reference to the schematic diagrams. When detailing the embodiments of this application, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not according to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this application. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0043] With the rapid development of semiconductor and related technologies, the demand for heat dissipation for semiconductor chips is also increasing.

[0044] Thin-film nucleus boiling heat transfer technology was proposed by Renkun Chen of the University of California in 2018. This technology confines the boiling working fluid within a narrow slit region between the hydrophobic film and the heat exchange surface. When boiling bubbles collide with the surface of the hydrophobic film, the hydrophobic effect tears the bubbles apart from the top, and the vapor inside the bubbles is expelled by the pressure drop across the hydrophobic film, thus achieving forced gas-liquid separation. Thin-film nucleus boiling heat transfer technology produces extremely high heat transfer efficiency, with a critical heat flux exceeding 1000 W / cm³. 2 The heat transfer coefficient can reach 1000kW / (m²). 2 K) is an important way to solve the problem of heat dissipation in ultra-high heat flux density in the future.

[0045] However, thin-film nucleus boiling heat transfer technology is still limited by the problem of bubble detachment at high heat flux densities, causing its heat transfer coefficient to decrease significantly with increasing heat flux density. Furthermore, the application of thin-film nucleus boiling heat transfer technology in semiconductor chip packaging heat dissipation is also limited.

[0046] Therefore, there is a need for thin-film nucleo-boiling phase change cooling structures for heat dissipation of semiconductor chips.

[0047] Based on this, this application provides a method for manufacturing a thin-film nucleus boiling phase change cooling structure, comprising: forming a boiling cavity structure on a first substrate to form a heat transfer surface of the thin-film nucleus boiling phase change cooling structure; etching a second substrate of a first thickness from a first surface of a second substrate to form a plurality of grooves, i.e., etching grooves from the first surface into the second substrate; etching a second substrate of a second thickness from the second surface of the second substrate to the grooves to form a plurality of channels, i.e., etching from the second surface so that the grooves form channels penetrating a portion of the thickness of the second substrate, wherein the thickness of the second substrate is the sum of the first thickness and the second thickness, thus forming channels by etching two sides of the second substrate, which can be used for gas exhaust; forming a nanoneedle-like structure on the first surface, and modifying the nanoneedle-like structure with a surface hydrophobic silane coupling agent to form an ultra-hydrophobic nanoneedle-like surface structure, which can be used to induce bubbles to detach from the liquid film, thereby increasing the bubble bursting rate and improving the heat transfer coefficient. The ultra-sparse nanoneedle-like surface structure and channels constitute an ultra-sparse porous silicon film structure. Combined with the boiling chamber structure and the ultra-sparse porous silicon film structure, with the ultra-sparse nanoneedle-like surface structure facing the boiling chamber structure, a liquid film can be formed between the boiling chamber structure and the ultra-sparse porous silicon film structure. Furthermore, the ultra-sparse porous silicon film structure facilitates the detachment and discharge of bubbles from the liquid film. Therefore, this application provides a method for manufacturing an ultra-sparse porous silicon film structure that influences gas-liquid separation efficiency. By manufacturing the channels and ultra-sparse nanoneedle-like surface structure included in the ultra-sparse porous silicon film structure, the gas-liquid separation efficiency can be greatly improved, enabling its application in the field of semiconductor chip packaging heat dissipation to meet the heat dissipation requirements of semiconductor chips.

[0048] To better understand the technical solution and effects of this application, the specific embodiments will be described in detail below with reference to the accompanying drawings.

[0049] refer to Figure 1 As shown, Figure 1 This is a cross-sectional schematic diagram of a thin liquid film nucleus boiling phase change cooling structure provided in an embodiment of this application. The thin liquid film nucleus boiling phase change cooling structure 100 provided in this embodiment includes a boiling cavity structure 110 and an ultraporous silicon film structure 120 stacked sequentially.

[0050] In embodiments of this application, the boiling chamber structure 110 includes a boiling chamber 111 and a micropillar structure array 112. The micropillar structure array 112 is located at the bottom of the boiling chamber 111. The boiling chamber 111 is obtained by etching a first substrate, and the micropillar structure array 112 is obtained by laser etching the bottom of the boiling chamber 111. The micropillar structure array 112 includes multiple columnar protrusions, which can realize capillary transport of liquid.

[0051] The boiling chamber structure 110 also includes a superhydrophilic coating (not shown in the figure), which covers the micropillar structure array 112. The superhydrophilic coating exhibits superhydrophilicity to the liquid. Specifically, the material of the superhydrophilic coating can be silicon oxide. After etching to obtain the micropillar structure array 112, silicon oxide nanoparticles can be sprayed, followed by sintering at a high temperature to finally obtain the superhydrophilic coating. The high temperature range is 700℃-800℃. The superhydrophilic coating can effectively limit the contact area between bubbles and the surface of the boiling chamber structure 110, reduce bubble adhesion, limit bubble expansion on the surface of the boiling chamber structure 110, and achieve bubble detachment reinforcement.

[0052] The boiling chamber structure 110 has a superhydrophilic coating on one side surface, which can serve as the heat exchange surface of the thin liquid film nucleate boiling phase change cooling structure 100. The thickness of the liquid film can be controlled by adjusting the height of the boiling chamber structure 110. The structural parameters of the micropillar array 112 include the micropillar array density and the micropillar structure size. The capillary effect of the micropillar array 112 can be adjusted by changing the micropillar array density and the micropillar structure size. For example, by changing the micropillar array density and the micropillar structure size, the capillary effect of the heat exchange surface can be enhanced, the expansion of boiling bubbles on the heat exchange surface can be limited, and the detachment of bubbles from the liquid film can be enhanced, thereby improving the heat transfer efficiency.

[0053] In the embodiments of this application, the superhydrophobic silicon film structure 120 includes channels 121 and superhydrophobic nanoneedle-like surface structures 122. The superhydrophobic silicon film structure 120 is hydrophobic, mainly achieved by utilizing the superhydrophobic nanoneedle-like surface structures 122. In the direction perpendicular to one side of the surface of the superhydrophobic silicon film structure 120, the channels 121 and the superhydrophobic nanoneedle-like surface structures 122 do not overlap, that is, the superhydrophobic nanoneedle-like surface structures 122 do not obstruct the gas flow in the channels 121, so as to realize the smooth discharge of gas from the thin liquid film nucleus boiling phase change cooling structure 100.

[0054] The superhydrophobic nanoneedle-like surface structure 122 mainly comprises copper oxide nanoneedle-like structure 1221 and hydrophobic silane coupling agent 1222, as referenced. Figure 2 As shown. The material of the copper oxide nanoneedle structure 1221 is copper oxide. The copper oxide nanoneedle structure 1221 has a conical or pyramidal structure. The hydrophobic silane coupling agent 1222 is used to cover or encapsulate the copper oxide nanoneedle structure 1221, thereby further improving the hydrophobicity of the copper oxide nanoneedle structure 1221. The copper oxide nanoneedle structure 1221 has a tip and a bottom, so the ultra-hydrophobic nanoneedle surface structure 122 also has a tip and a bottom, with the bottom close to the pore 121 and the tip away from the pore 121. The copper oxide nanoneedle structure 1221 can effectively promote bubble rupture, and combined with the hydrophobic silane coupling agent 1222, it can effectively enhance the detachment of bubbles from the liquid film.

[0055] Specifically, in order to improve the hydrophobicity of the superhydrophobic porous silicon film structure 120, a hydrophobic film layer can also be formed on the sidewall of the pore 121. This hydrophobic film layer can be a hydrophobic silane coupling agent 1222.

[0056] The pores 121 can be used to expel gas from the bubbles, and the ultra-sparse nanoneedle-like surface structure 122 can be used to induce the liquid film rupture between the ultra-sparse porous silicon film structure 120 and the bubbles, thereby enhancing the detachment of the bubbles from the liquid film, thus increasing the bubble rupture rate and improving the heat transfer coefficient.

[0057] As one possible implementation, to protect the sidewalls of the channel 121, a first protective layer 123 can be provided between the sidewalls of the channel 121 and the hydrophobic silane coupling agent 1222, as shown in the reference. Figure 2 As shown. The material of the first protective layer 123 can be selected from materials suitable for the growth of the hydrophobic silane coupling agent 1222, thus achieving greater adhesion of the hydrophobic silane coupling agent 1222. Specifically, the material of the first protective layer 123 can be silicon oxide.

[0058] In practical applications, a second protective layer 104 can also be provided on the surface of the superporous silicon film structure 120 to protect the superporous silicon film structure 120. (Refer to...) Figure 2As shown. The material of the second protective layer 104 can be silicon oxide.

[0059] In embodiments of this application, the superporous silicon film structure 120 further includes a support structure 124, as referenced. Figure 1 As shown, the support structure 124 is used to support the ultra-sparse nanoneedle-like surface structure 122 and the channels 121, thereby improving the mechanical strength of the entire ultra-sparse porous silicon film structure 120. The material of the support structure 124 is the same as the material of the structure between adjacent channels 121. The support structure 124 is located on the side of the ultra-sparse porous silicon film structure 120 away from the ultra-sparse nanoneedle-like surface structure 122.

[0060] The superporous silicon film structure 120 also includes a metal layer 125, as shown in the reference. Figure 2 As shown, a metal layer 125 is disposed at the bottom of the ultra-resilient nanoneedle-like surface structure 122 to assist in the formation of the ultra-resilient nanoneedle-like surface structure 122. The metal layer 125 can be a stack of titanium and copper layers, with the titanium layer disposed on the side of the copper layer away from the ultra-resilient nanoneedle-like surface structure 122, meaning the copper layer is closer to the ultra-resilient nanoneedle-like surface structure 122. This allows for better formation of the copper oxide nanoneedle-like structure 1221. The titanium layer enhances the adhesion between the copper layer and the second protective layer 104, improving the bonding effect.

[0061] In the embodiments of this application, the boiling chamber structure 110 and the ultraporous silicon film structure 120 can be combined, as shown in the reference. Figure 1 As shown, the bonding can be achieved using a welding process. The ultra-sparse nanoneedle-like surface structure 122 faces the boiling chamber structure 110, specifically, the tips of the ultra-sparse nanoneedle-like surface structure 122 face the boiling chamber structure 110. In this way, a liquid film can be formed between the boiling chamber structure 110 and the ultra-sparse porous silicon film structure 120, and the ultra-sparse porous silicon film structure 120 is used to enhance the detachment of boiling bubbles from the liquid film, thereby improving heat transfer efficiency.

[0062] In embodiments of this application, the thin liquid film nucleus boiling phase change cooling structure 100 further includes a metal manifold structure 130, see reference. Figure 1 As shown, the metal manifold structure 130 can be combined with the ultra-porous silicon film structure 120. Specifically, the support structure 124 and the metal manifold structure 130 can be combined using a welding process, wherein the ultra-porous nanoneedle surface structure 122 is located away from the metal manifold structure.

[0063] The metal manifold structure 130 may include a liquid inlet channel 131 and a gas outlet channel 132. Liquid can enter the interior of the thin-film nucleus boiling phase change cooling structure 100 through the liquid inlet channel 131. The interior of the thin-film nucleus boiling phase change cooling structure refers to the space between the boiling chamber structure 110 and the ultra-porous silicon film structure 120. The liquid inlet channel 131 can be used to replenish liquid under ultra-high heat flux density, avoiding the loss of liquid due to phase change vaporization and the resulting decrease in heat transfer efficiency. Gas flow can exist between the gas outlet channel 132 and the channel 121, so that the gas in the bubbles can be discharged from the thin-film nucleus boiling phase change cooling structure 100 through the channel 121 and the gas outlet channel 132.

[0064] In practical applications, the materials of the boiling chamber structure 110, the ultraporous silicon film structure 120, and the metal manifold structure 130 can be semiconductor materials, such as silicon, in order to achieve heat dissipation packaging for semiconductor chips.

[0065] In the embodiments of this application, the waterproofness and breathability of the ultraporous silicon film structure 120 can be adjusted by modifying the structural parameters of the channel 121, thereby adjusting the heat transfer efficiency of the entire thin liquid film nucleus boiling phase change cooling structure 100. The structural parameters of the channel 121 include pore diameter, porosity, and channel length. A larger pore diameter results in poorer waterproofness and better breathability. Porosity refers to the ratio of pore diameter to the distance between adjacent channels 121; in this case, the pore diameter can be the diameter itself. A larger porosity results in better breathability. A shorter channel length results in better breathability. Therefore, optimal waterproofness and breathability can be achieved by actually adjusting the three structural parameters of the channel 121.

[0066] In the embodiments of this application, the hydrophobicity of the superhydrophobic porous silicon film structure 120 is adjusted by modifying the structural parameters of the superhydrophobic nanoneedle surface structure 122, thereby adjusting the heat transfer efficiency of the entire thin-film nucleus boiling phase change cooling structure 100. The structural parameters of the superhydrophobic nanoneedle surface structure 122 include needle density, needle diameter, and needle length. A higher needle density results in better hydrophobicity. A smaller needle diameter indicates a sharper tip and better hydrophobicity. A longer needle length may lead to poorer stability. Therefore, optimal hydrophobicity can be achieved by practically adjusting the three structural parameters of the superhydrophobic nanoneedle surface structure 122.

[0067] Based on the thin-film nucleus boiling phase change cooling structure provided in the above embodiments, this application also provides a method for manufacturing the thin-film nucleus boiling phase change cooling structure. (See reference...) Figure 3 The diagram shows a flowchart of a method for manufacturing a thin liquid film nucleus boiling phase change cooling structure according to an embodiment of this application. The method includes the following steps:

[0068] S101, a boiling cavity structure 110 is formed on the first substrate 101, reference Figure 4 As shown.

[0069] In embodiments of this application, a boiling chamber structure 110 may be formed on a first substrate 101. The first substrate may be a semiconductor substrate, such as silicon. The boiling chamber structure 110 may contact the semiconductor chip, receive the heat flux density of the semiconductor chip, and thereby provide heat dissipation for the semiconductor chip.

[0070] Specifically, the first substrate 101 can be etched to form a boiling cavity 111, and a micropillar structure array 112 can be formed at the bottom of the boiling cavity 111. Specifically, the bottom of the boiling cavity 111 can be laser-etched to obtain a micropillar structure array 112 with multiple columnar protrusions. Then, a superhydrophilic coating is grown on the micropillar structure array 112. The superhydrophilic coating material can be silicon oxide, which has excellent hydrophilicity. Specifically, silicon oxide nanoparticles can be sprayed and then sintered at a high temperature to finally obtain the superhydrophilic coating. The high temperature range is 700℃-800℃.

[0071] S102, etching a first-thickness second substrate 102 from a first surface of the second substrate 102 to form a plurality of grooves 103, reference. Figure 5 As shown.

[0072] In embodiments of this application, the second substrate 102 may be a semiconductor substrate, such as a silicon substrate. A first thickness of the second substrate 102 can be etched from its first surface to form a plurality of grooves 103. During etching, a patterned mask layer can first be formed on the first surface of the second substrate 102. Using the mask layer as a mask, the first thickness of the second substrate 102 is etched, and the depth of the formed grooves 103 is also the first thickness. Specifically, the etching process is deep reactive ion etching (DRIE). The mask layer can be made of silicon oxide, and the mask layer may not need to be removed; it can subsequently serve as a first protective layer 123 on the first surface of the second substrate 102.

[0073] In embodiments of this application, to protect the sidewalls of the groove 103, a first protective layer 123 can be formed on the sidewalls and bottom of the groove 103, and then the first protective layer 123 at the bottom of the groove 103 can be removed. (Refer to...) Figure 6As shown. The material of the first protective layer 123 can be selected from materials suitable for the growth of the hydrophobic silane coupling agent 1222, so that the hydrophobic silane coupling agent 1222 can achieve greater adhesion in the subsequent process. Specifically, the material of the first protective layer 123 can be silicon oxide. The first protective layer 123 can be grown using plasma-enhanced chemical vapor deposition (PECVD).

[0074] In practical applications, the first protective layer 123 also covers the first surface.

[0075] S103, etching a second thickness of the second substrate 102 from the second surface of the second substrate 102 to the groove 103 to form a plurality of channels 121, referenced. Figure 7 As shown.

[0076] In the embodiments of this application, after forming the groove 103, the second substrate 102 of a second thickness can be etched from the second surface of the second substrate 102 to the groove 103, thereby forming a plurality of channels 121 from the multiple grooves 103. Similar to forming the groove 103, during etching, a patterned mask layer can first be formed on the second surface of the second substrate 102. Using the mask layer as a mask, the second substrate 102 of a second thickness is etched. The specific etching process is deep reactive ion etching. The sum of the first thickness and the second thickness is the thickness of the second substrate 102, so that the material at the bottom of the groove 103 can be completely etched, thereby forming the channels 121 that allow air to pass through. The material of the mask layer can be silicon oxide, and the mask layer does not need to be removed and can subsequently serve as a second protective layer 104 for the second substrate 102.

[0077] Specifically, the structural parameters of the formed channel 121 can be adjusted by adjusting the pattern of the mask layer and the first thickness of the etching, thereby adjusting the waterproofness and breathability of the subsequently formed ultra-porous silicon film structure 120.

[0078] In practical applications, during the etching of the second substrate 102 from the second surface, a support structure 124 is also formed. The support structure 124 is used to support the channels 121 and improve the mechanical strength of the subsequently formed ultraporous silicon film structure 120. The material of the support structure 124 is the same as the material of the second substrate 102.

[0079] In embodiments of this application, after etching to obtain a plurality of channels 121, a metal layer 125 can be formed on the first surface, as shown in the reference. Figure 8As shown, the metal layer 125 is used to assist in the subsequent formation of the ultra-sparse nanoneedle-like surface structure 122. Specifically, the metal layer 125 can be formed using a sputtering process. The metal layer 125 can be a stack of titanium and copper layers, with the titanium layer disposed on the side of the copper layer closer to the first surface, i.e., the copper layer is further away from the first surface, which allows for better formation of the ultra-sparse nanoneedle-like surface structure 122. The titanium layer is used to improve the adhesion between the copper layer and the second protective layer 104 material, thereby enhancing the bonding effect.

[0080] S104, forming a nanoneedle-like structure 105 on the first surface, and modifying the nanoneedle-like structure 105 with a surface hydrophobic silane coupling agent 1222 to form an ultrahydrophobic nanoneedle-like surface structure 122. (Reference) Figure 10 As shown.

[0081] In embodiments of this application, a nanoneedle-like structure 105 can be formed on the first surface. Specifically, after forming a metal layer 125 on the first surface, the nanoneedle-like structure 105 can be formed on the surface of the metal layer 125. The nanoneedle-like structure 105 has a conical or pyramidal structure, and has a tip and a bottom. The bottom is closer to the first surface, and the tip is farther from the first surface. (Refer to...) Figure 9 As shown.

[0082] The nanoneedle structure 105 can be a copper hydroxide nanoneedle structure, in which case the material of the nanoneedle structure 105 is copper hydroxide. Specifically, copper hydroxide nanoneedle structures can be formed on the first surface by electrochemical deposition of copper hydroxide, and then heated in air to form copper oxide nanoneedle structures 1221. The heating temperature range is 200℃-300℃. The material of the copper oxide nanoneedle structure 1221 is copper oxide. The copper oxide nanoneedle structure 1221 can also have a conical or pyramidal structure.

[0083] Specifically, the structural parameters of the formed nanoneedle structure 105 can be adjusted by adjusting process parameters such as electrolyte concentration, current density, and deposition time during electrochemical deposition, thereby adjusting the hydrophobicity of the subsequently formed ultraporous silicon film structure 120.

[0084] After forming the copper oxide nanoneedle structure 1221, the copper oxide nanoneedle structure 1221 can be plasma activated, and then modified with a surface hydrophobic silane coupling agent 1222 to form an ultrahydrophobic nanoneedle surface structure 122. (Refer to...) Figure 10 As shown. Hydrophobic silane coupling agent 1222 is used to cover or encapsulate copper oxide nanoneedle structures 1221.

[0085] Copper oxide nanoneedle structures 1221 and hydrophobic silane coupling agent 1222 constitute an ultrahydrophobic nanoneedle surface structure 122. The copper oxide nanoneedle structures 1221 have a tip and a bottom, and thus the ultrahydrophobic nanoneedle surface structure 122 also has a tip and a bottom, with the bottom closer to the pores 121 and the tip farther from the pores 121. The copper oxide nanoneedle structures 1221 effectively promote bubble rupture, and the combination with the hydrophobic silane coupling agent 1222 effectively enhances bubble detachment from the liquid film.

[0086] In the embodiments of this application, to improve the hydrophobicity of the ultraporous silicon film structure 120, a hydrophobic film layer can also be formed on the sidewalls of the pores 121. This hydrophobic film layer can be a hydrophobic silane coupling agent 1222. That is, when forming the hydrophobic silane coupling agent 1222 covering the copper oxide nanoneedle structure 1221, the hydrophobic silane coupling agent 1222 can also be formed on the sidewalls of the pores 121. Since the sidewalls of the pores 121 are provided with a first protective layer 123 to assist the growth of the hydrophobic silane coupling agent 1222, the hydrophobic silane coupling agent 1222 can be easily grown on the first protective layer 123.

[0087] S105, combining the boiling chamber structure 110 and the ultraporous silicon film structure 120, reference Figure 11 As shown.

[0088] In the embodiments of this application, the boiling chamber structure 110 and the ultraporous silicon film structure 120 can be combined, specifically using a welding process. The ultraporous nanoneedle-like surface structure 122 faces the boiling chamber structure 110, specifically, the tips of the ultraporous nanoneedle-like surface structure 122 face the boiling chamber structure 110. In this way, liquid can form a liquid film between the boiling chamber structure 110 and the ultraporous silicon film structure 120, and the ultraporous silicon film structure 120 is used to enhance the detachment of boiling bubbles from the liquid film, thereby improving heat transfer efficiency.

[0089] In embodiments of this application, a metal manifold structure 130 can also be formed, and the metal manifold structure 130 and the ultra-porous silicon film structure 120 can be combined. Specifically, the support structure 124 and the metal manifold structure 130 can be combined using a welding process, wherein the ultra-porous nanoneedle-like surface structure 122 is located away from the metal manifold structure, as shown in the reference. Figure 1 As shown.

[0090] This application provides a method for manufacturing a thin-film nucleus boiling phase change cooling structure, comprising: forming a boiling cavity structure on a first substrate to form a heat transfer surface of the thin-film nucleus boiling phase change cooling structure; etching a second substrate of a first thickness from a first surface of a second substrate to form a plurality of grooves, i.e., etching grooves from the first surface into the second substrate; etching a second substrate of a second thickness from the second surface of the second substrate to the grooves to form a plurality of channels, i.e., etching from the second surface so that the grooves form channels penetrating a portion of the thickness of the second substrate, wherein the thickness of the second substrate is the sum of the first thickness and the second thickness, thus forming channels by etching two sides of the second substrate, which can be used for gas exhaust; forming a nanoneedle-like structure on the first surface, and modifying the nanoneedle-like structure with a surface hydrophobic silane coupling agent to form an ultra-hydrophobic nanoneedle-like surface structure, which can be used to induce bubbles to detach from the liquid film, thereby increasing the bubble collapse rate and improving the heat transfer coefficient. The ultra-sparse nanoneedle-like surface structure and channels constitute an ultra-sparse porous silicon film structure. Combined with the boiling chamber structure and the ultra-sparse porous silicon film structure, with the ultra-sparse nanoneedle-like surface structure facing the boiling chamber structure, a liquid film can be formed between the boiling chamber structure and the ultra-sparse porous silicon film structure. Furthermore, the ultra-sparse porous silicon film structure facilitates the detachment and discharge of bubbles from the liquid film. Therefore, this application provides a method for manufacturing an ultra-sparse porous silicon film structure that influences gas-liquid separation efficiency. By manufacturing the channels and ultra-sparse nanoneedle-like surface structure included in the ultra-sparse porous silicon film structure, the gas-liquid separation efficiency can be greatly improved, enabling its application in the field of semiconductor chip packaging heat dissipation to meet the heat dissipation requirements of semiconductor chips.

[0091] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the method embodiments are basically similar to the structural embodiments, so they are described more simply; relevant parts can be referred to the descriptions of the structural embodiments.

[0092] The descriptions of the processes or structures corresponding to the above figures each have their own emphasis. For parts of a process or structure that are not described in detail, please refer to the relevant descriptions of other processes or structures.

[0093] The above description is merely a preferred embodiment of this application. Although this application has disclosed preferred embodiments above, it is not intended to limit this application. Any person skilled in the art can make many possible variations and modifications to the technical solutions of this application using the methods and techniques disclosed above, or modify them into equivalent embodiments with equivalent changes, without departing from the scope of the technical solutions of this application. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application without departing from the content of the technical solutions of this application shall still fall within the protection scope of the technical solutions of this application.

[0094] Based on the implementation methods provided in the above aspects, this application can be further combined to provide more implementation methods.

Claims

1. A method for manufacturing a thin liquid film nucleus boiling phase change cooling structure, characterized in that, include: A boiling chamber structure is formed on the first substrate; A plurality of grooves are formed by etching the second substrate of a first thickness from the first surface of the second substrate; A second substrate of a second thickness is etched from the second surface of the second substrate to the groove to form a plurality of channels, wherein the thickness of the second substrate is the sum of the first thickness and the second thickness; A nanoneedle-like structure is formed on the first surface, and the nanoneedle-like structure is modified with a surface hydrophobic silane coupling agent to form an ultra-hydrophobic nanoneedle-like surface structure; the ultra-hydrophobic nanoneedle-like surface structure and the channels constitute an ultra-hydrophobic porous silicon film structure; The nanoneedle-like structure is conical or pyramidal, and has a tip and a bottom. The bottom is close to the first surface, and the tip is away from the first surface. In the direction perpendicular to one side of the ultra-porous silicon film structure, the channels and the ultra-porous nanoneedle-like surface structure do not overlap, so that the ultra-porous nanoneedle-like surface structure does not obstruct the gas flow in the channels. Combining the boiling chamber structure and the ultra-porous silicon film structure, the tip of the ultra-porous nanoneedle surface structure faces the boiling chamber structure. The ultra-porous nanoneedle surface structure is used to induce the liquid film rupture between the ultra-porous silicon film structure and the bubbles, thereby enhancing the detachment of the bubbles from the liquid film.

2. The manufacturing method according to claim 1, characterized in that, The nanoneedle structure includes copper hydroxide nanoneedle structure and copper oxide nanoneedle structure; The step of forming a nanoneedle-like structure on the first surface and modifying the nanoneedle-like structure with a surface hydrophobic silane coupling agent to form an ultrahydrophobic nanoneedle-like surface structure includes: The copper hydroxide nanoneedle structure is formed on the first surface by electrochemical deposition of copper hydroxide. The copper hydroxide nanoneedle structure is heated in air to form the copper oxide nanoneedle structure. The copper oxide nanoneedle structure is modified with a surface hydrophobic silane coupling agent to form an ultrahydrophobic nanoneedle surface structure.

3. The manufacturing method according to claim 2, characterized in that, Prior to forming the copper hydroxide nanoneedle structure on the first surface using electrochemical deposition of copper hydroxide, the method further includes: A metal layer is formed on the first surface, wherein the metal layer is a stack of titanium and copper layers.

4. The manufacturing method according to claim 1, characterized in that, Before etching the second substrate of a second thickness from the second surface of the second substrate to the groove, the method further includes: A first protective layer is formed on the sidewall of the groove, the first protective layer being used to assist the growth of the hydrophobic silane coupling agent; When modifying the nanoneedle-like structure with a surface-hydrophobic silane coupling agent to form an ultrahydrophobic nanoneedle-like surface structure, the method further includes: The hydrophobic silane coupling agent is grown on the surface of the first protective layer.

5. The manufacturing method according to claim 4, characterized in that, The material of the first protective layer is silicon oxide.

6. The manufacturing method according to claim 1, characterized in that, The formation of the boiling chamber structure on the first substrate includes: The first substrate is etched to form a boiling chamber, and a micropillar structure array is formed at the bottom of the boiling chamber; A superhydrophilic coating is grown on the micropillar structure array.

7. The manufacturing method according to claim 1, characterized in that, The structural parameters of the pores include pore diameter, porosity, and pore length. The waterproofness and breathability of the ultra-porous silicon membrane structure can be adjusted by adjusting the structural parameters of the pores.

8. The manufacturing method according to claim 1, characterized in that, The structural parameters of the nanoneedle structure include needle density, needle diameter, and needle length. The hydrophobicity of the ultraporous silicon film structure can be adjusted by adjusting the structural parameters of the nanoneedle structure.

9. The manufacturing method according to claim 1, characterized in that, The method further includes: Forming a metal manifold structure; Combining the metal manifold structure and the ultra-porous silicon film structure, the ultra-porous nanoneedle-like surface structure is located away from the metal manifold structure.

10. A thin-film nucleus boiling phase change cooling structure, characterized in that, include: A boiling chamber structure and an ultra-porous silicon film structure are stacked sequentially. The ultra-porous silicon film structure includes an ultra-porous nanoneedle-like surface structure and channels, with the tips of the ultra-porous nanoneedle-like surface structure facing the boiling chamber structure. The nanoneedle-like structure is conical or pyramidal, and has a tip and a bottom. The bottom is close to the first surface, and the tip is away from the first surface. In the direction perpendicular to one side of the ultra-porous silicon film structure, the channels and the ultra-porous nanoneedle-like surface structure do not overlap, so that the ultra-porous nanoneedle-like surface structure does not obstruct the gas flow in the channels. A liquid film is formed between the boiling chamber structure and the ultra-porous silicon film structure. The phase change of the liquid film generates bubbles. The ultra-porous nanoneedle surface structure is used to induce the bubbles to detach from the liquid film. The ultra-porous nanoneedle surface structure is used to induce the liquid film between the ultra-porous silicon film structure and the bubbles to break, thereby enhancing the detachment of the bubbles from the liquid film.

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