Low-resistance micro-channel structure for high-power density packaging

Abstract

The invention provides a low-resistance micro-channel structure for high-power density packaging, and the micro-channel structure comprises a carrier plate which is provided with a chip stacking body; the shell is arranged on the carrier plate in a covering manner and is used for accommodating the chip stacking body; the heat dissipation micro-channel is defined by the carrier plate, the chip stacking body and the shell and surrounds the chip stacking body, the heat dissipation micro-channel comprises an inlet and an outlet which are formed in the side, away from the carrier plate, of the shell and used for allowing cooling liquid to enter and exit, and the inner wall of the micro-channel is provided with a hydrophilic surface. According to the invention, the cooling liquid pumping power can be reduced on the premise of ensuring the heat dissipation effect.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a low-resistance microchannel structure for high-power density packaging. Background Art

[0002] At present, stacked packaging technology is becoming more and more mature, and it is possible to package more semiconductor chips in a limited space. However, because multiple chips are stacked in a limited space, the total heat generated by all components is high, and the heat is difficult to be released smoothly from the limited space, which will affect the service life and operation status of the components. In the prior art, fans are usually used to cool down semiconductor chips in a stacked packaging structure, but they can only cool down the outside, resulting in poor cooling effect.

[0003] In order to meet the demand for efficient heat dissipation in high-power, high-density packaging, liquid heat dissipation microfluidic cooling technology can be used. The thermal conductivity of liquid is 15-25 times that of air. Therefore, liquid heat dissipation is the key to high-power, high-density packaging (such as high-density integrated packaging of high-computing power chips). However, the current liquid heat dissipation microfluidic system still requires a lot of pumping power to pump the liquid. Although this means that the heat dissipation is improved, the power consumption is extremely large, which is bound to make the total system power consumption very large, leading to a further increase in the power consumption of high-computing power chips. In particular, when multiple high-computing power chips are used in servers and other fields, the pumping power consumed is even higher. Summary of the invention

[0004] The object of the present invention is to provide a low-resistance microchannel structure for high-power density packaging, which is used to reduce the power of pumping coolant while ensuring the heat dissipation effect.

[0005] In order to solve the above technical problems, the present invention provides a low-resistance microchannel structure for high power density packaging, comprising:

[0006] A carrier board, on which a chip stack is arranged;

[0007] A housing, which is disposed on the carrier and accommodates the chip stack;

[0008] The heat dissipation microchannel is surrounded by the carrier, the chip stack and the shell and surrounds the chip stack, and includes an inlet and an outlet for cooling liquid to enter and exit, which are arranged on the side of the shell away from the carrier. The inner wall of the microchannel has a hydrophilic surface.

[0009] Optionally, the carrier is an intermediate board, the shell includes a side wall portion connected to the carrier and a cover portion connected to the side wall portion and away from the carrier, and the inlet and the outlet are both arranged in the cover portion directly above the chip stack.

[0010] Optionally, the carrier and the chip stack are connected by an intermediate layer, and the shell includes a bottom plate portion, a side wall portion and a cover plate portion, the bottom plate portion is connected to the carrier and is close to the intermediate plate, the side wall portion is connected to the bottom plate portion, the cover plate portion is connected to the side wall portion and is away from the bottom plate portion, and the inlet and the outlet are respectively arranged in the cover plate portions on both sides above the chip stack.

[0011] Optionally, the chip stack includes at least two layers of chips bonded in sequence, and at least part of the chips are provided with microchannels for cooling liquid to flow.

[0012] Optionally, a channel layer is further provided on the top surface of the chip stack, the channel layer is at least partially in contact with the cover plate portion, and a plurality of grooves are provided in the channel layer as micro-channels for the flow of cooling liquid.

[0013] Optionally, the outlet includes a plurality of capillary structures, and the capillary structures are integrally formed with the shell or are independent components embedded in the outlet.

[0014] Optionally, one inlet and at least two outlets are provided on the shell, and at least two outlets are arranged in parallel at one end opposite to the inlet.

[0015] Optionally, after the heat dissipation micro-channel is formed, a physical and / or chemical method is used to perform a hydrophilic treatment on the heat dissipation micro-channel to form the hydrophilic surface in the heat dissipation micro-channel.

[0016] Optionally, the hydrophilicity of the outer wall of the chip stack in the microfluidic channel is greater than or equal to the hydrophilicity of the inner wall of the shell.

[0017] Optionally, the physical method includes treating the inner wall of the heat dissipation microchannel with oxygen plasma, and the chemical method includes forming a hydrophilic self-assembled monolayer on the inner wall of the heat dissipation microchannel.

[0018] In summary, the low-resistance microfluidic structure for high-power density packaging of the present invention includes: a carrier, a shell and a heat dissipation microfluidic channel. A chip stack is provided on the carrier; the shell cover is provided on the carrier and accommodates the chip stack; the heat dissipation microfluidic channel is surrounded by the carrier, the chip stack and the shell and surrounds the chip stack, and includes an inlet and an outlet for the coolant to enter and exit, which are provided on the side of the shell away from the carrier, and the inner wall of the microfluidic channel has a hydrophilic surface. In the present invention, the inner wall of the microfluidic channel has a hydrophilic surface, and the hydrophilic surface is used to improve the wettability (high wettability) of the coolant on the inner wall of the microfluidic channel, thereby reducing the flow resistance of the coolant in the microfluidic channel, and thus reducing the pumping power of the coolant in the microfluidic channel. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Those skilled in the art should understand that the drawings are provided for a better understanding of the present invention, but do not constitute any limitation on the scope of the present invention.

[0020] Figure 1 is a cross-sectional schematic diagram of a low-resistance microfluidic channel structure provided in Example 1;

[0021] Figure 2a is a top view schematic diagram of the low resistance microfluidic channel structure provided in Example 1;

[0022] Figure 2b is a top view schematic diagram of another microfluidic channel structure provided in Example 1;

[0023] Figure 2c is a top view schematic diagram of another microfluidic channel structure provided in Example 1;

[0024] Figure 3 is a cross-sectional schematic diagram of a low-resistance microfluidic channel structure provided in Example 2;

[0025] Figure 4a is a top view schematic diagram of a low resistance microfluidic channel structure provided in Example 2;

[0026] Figure 4b is a top view schematic diagram of another microfluidic channel structure provided in Example 2;

[0027] Figure 4c It is a top view schematic diagram of another microfluidic channel structure provided in Example 2.

[0028] In the attached figure:

[0029] 10-carrier; 11-packaging substrate; 12-conductive through hole; 13-metal solder ball; 20-housing; 21-bottom plate; 22-side wall; 23-cover plate; 24-inlet; 25-outlet; 25a-capillary structure; 25b-non-capillary structure; 30-chip stack; 31-chip; 32-channel layer; 33-groove. DETAILED DESCRIPTION

[0030] In order to make the purpose, advantages and features of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In addition, the structure shown in the drawings is often a part of the actual structure. In particular, the emphasis of each drawing is different, and sometimes different scales are used.

[0031] As used in the present invention, the singular forms "one", "an", and "the" include plural objects, the term "or" is usually used to include the meaning of "and / or", the term "several" is usually used to include the meaning of "at least one", and the term "at least two" is usually used to include the meaning of "two or more". In addition, the terms "first", "second", and "third" are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as "first", "second", and "third" may explicitly or implicitly include one or at least two of the features, unless the content clearly indicates otherwise.

[0032] Embodiment 1

[0033] Embodiment 1 provides a low-resistance microchannel structure for high power density packaging.

[0034] Figure 1 is a cross-sectional schematic diagram of a low-resistance microfluidic channel structure provided in Example 1; Figure 2a 1 is a top view schematic diagram of the low resistance microfluidic channel structure provided in Example 1.

[0035] like Figure 1 and Figure 2a As shown, the low-resistance microfluidic structure for high power density packaging provided in this embodiment includes: a carrier 10, a housing 20 and a heat dissipation microfluidic channel. A chip stack 30 is provided on the carrier 10; the housing 20 is covered on the carrier 10 and accommodates the chip stack 30; the heat dissipation microfluidic channel is surrounded by the carrier 10, the chip stack 30 and the housing 20 and surrounds the chip stack 30, and includes an inlet 24 and an outlet 25 for the coolant to enter and exit, which are arranged on the side of the housing 20 away from the carrier 10, and the inner wall of the microfluidic channel has a hydrophilic surface.

[0036] In this embodiment, the carrier 10 may be an interposer having two opposite surfaces (i.e., a first surface and a second surface), and the material thereof may be, for example, silicon or glass. The interposer is provided with a conductive through hole 12 (a silicon through hole or a glass through hole filled with metal, such as copper), and metal solder balls 13 (such as tin solder balls) may be provided on both sides of the conductive through hole 12. The chip stack 30 is bonded to the first surface of one side of the conductive through hole 12 (interposer) using the metal solder balls 13, and the second surface of the interposer is connected to other packaging substrates 11 (such as PCB printed boards). The chip stack 30 may include at least two sequentially stacked chips 31, each chip 31 is provided with a silicon through hole and a pad, and the pad and the silicon through hole are provided with metal solder balls 13 for bonding the above-mentioned multiple chips 31.

[0037] Please continue to refer to Figure 1The shell 20 can be made of a material that is easy to process and suitable for being tightly connected (e.g., bonded) to the surface of the carrier 10. In this embodiment, the shell 20 can be made of silicon, that is, prepared from a silicon wafer by photolithography and etching. The shell 20 can be bowl-shaped, buckled (covered) on the carrier 10 and forming a cavity for accommodating the chip stack 30. It can include a side wall portion 22 perpendicular to the surface of the carrier 10 and a cover portion 23 parallel to the surface of the carrier 10. The side wall portion 22 is connected to the surface of the carrier 10. The cover portion 23 is connected to the side wall portion 22 and is away from the carrier 10. The cover portion 23 can be provided with an inlet 24 and an outlet 25 for the coolant to enter and exit. The inlet 24 and the outlet 25 can be arranged at opposite ends of the cover portion 23. Thus, the above-mentioned cavity, inlet 24 and outlet 25 can form a heat dissipation microfluidic channel surrounding the chip stack 30, wherein the space between the side wall portion 22 of the shell 20 and the side of the chip stack 30 serves as a microfluidic branch of the heat dissipation microfluidic channel surrounding the chip stack 30, and a channel layer 32 is provided on the top surface of the chip stack 30, and a plurality of grooves 33 are provided on the surface of the channel layer 32 as microfluidic branches covering the surface of the chip stack 30 of the heat dissipation microfluidic channel.

[0038] In this embodiment, the channel layer 32 can also be used as a heat sink component to extract the heat of the chip stack 30, the top of the channel layer 32 is in contact with the cover portion 23 of the shell 20, and the inlet 24 and outlet 25 of the heat dissipation microchannel are opened in the cover portion 23 directly above the channel layer 32, so that the groove 33 near the inlet 24 in the channel layer 32 is used as a liquid separation branch of the heat dissipation microchannel, and the groove 33 near the outlet 25 in the channel layer 32 is used as a liquid collection branch of the heat dissipation microchannel. Of course, in other examples of this embodiment, the cavity formed by the shell 20 and the carrier 10 can also be provided with at least two spaced chip stacks 30 for dissipating heat for multiple chip stacks 30 at the same time. In addition, in some other examples of this embodiment, the top of the channel layer 32 is in contact with the cover portion 23 of the shell 20 or not in contact with the cover portion 23 of the shell 20, and the inlet 24 and outlet 25 of the microchannel are opened in the cover portion 23 on both sides directly above the channel layer 32.

[0039] In particular, in this embodiment, the inner wall of the above-mentioned microchannel has a hydrophilic surface, and the hydrophilic surface is used to improve the wettability (high wettability) of the coolant on the inner wall of the microchannel, thereby reducing the flow resistance of the coolant in the microchannel, and thus reducing the pumping power of the coolant in the microchannel. Among them, after the heat dissipation microchannel is formed, the heat dissipation microchannel can be hydrophilized by physical and / or chemical methods to form a hydrophilic surface in the heat dissipation microchannel. In one example, the physical method can be, for example: oxygen (such as oxygen) plasma treatment is passed into the microchannel, and the inner wall of the microchannel is treated with oxygen plasma to form a hydrophilic surface. In another example, the chemical method can be, for example, including: passing a liquid including a hydrophilic self-assembled monolayer component into the microchannel to form a hydrophilic self-assembled monolayer on the inner wall of the microchannel. Of course, the hydrophilic surface formed above and its properties can match the specific type of coolant, and the coolant can be water, ethanol or Freon, etc. Taking the wetting angle as an example to characterize hydrophilicity, the wetting angle between the coolant and the microchannel surface may be less than 90°.

[0040] In addition, in a preferred example, before packaging to form the microchannel, the outer wall of the chip stack 30 (the outer wall exposed in the cavity) can be hydrophilically treated to further improve the hydrophilicity of the outer wall of the chip stack 30, that is, to improve the wettability of the outer wall of the chip stack 30 by the coolant, thereby helping to reduce resistance and improve the cooling effect.

[0041] Further, such as Figure 2a As shown in the top view, a plurality of capillary structures 25a can be provided at the outlet 25, and the coolant can be guided out (pumped out) from the outlet 25 by the spontaneous climbing of the coolant in the capillary structure 25a, so as to ensure the switching of the coolant in the microchannel under the premise of further reducing the pumping power. The capillary structure 25a can be a through hole with a high aspect ratio (i.e., an elongated shape), and its maximum diameter can be related to the type of coolant and the hydrophilicity of the inner wall. For example, if the inner wall of the capillary structure 25a is hydrophilically treated silicon oxide, the capillary structure 25a has a diameter of no more than 10 mm and can achieve capillary force adsorption at a height of more than 20 m. Figure 2a In the example shown, the outlet 25 may be composed of a plurality of capillary structures 25a, that is, all through holes of the outlet 25 are capillary structures. Figure 2b As shown in the top view, the outlet 25 may be composed of a plurality of capillary structures 25a and a plurality of non-capillary structures 25b (which have a relatively large aspect ratio and cannot form an obvious capillary effect), that is, including the capillary structure 25a and the non-capillary structure 25b, to ensure that the flow rate of the outlet 25 meets the requirements. In other examples, such as Figure 2cAs shown in the top view, at least two (for example, two) outlets 25 formed by capillary structures 25a may be provided on the housing 20 (cover portion 23) to take into account the flow rate of the outlets 25 while utilizing the capillary effect. The two outlets 25 may be arranged side by side at one end relative to the inlet 24, and the two outlets 25 may be kept at the same distance from the inlet 24. In this embodiment, the hydrophilic surface in the capillary structure 25a may further enhance the capillary force of the coolant therein, so that the coolant can quickly climb without resistance, further reducing the resistance of the inlet 24 and the outlet 25, thereby reducing the pumping power.

[0042] It is understandable that the capillary structure 25a of the above-mentioned outlet may be an independent component integrally formed with the shell or embedded in the outlet. The capillary structure integrally formed with the shell (formed by part of the shell) may have a hydrophilicity close to that of the inner wall of the microchannel. For example, if the shell is made of silicon, the shell surface (silicon surface) may be oxidized to form silicon oxide as the inner wall of the microchannel, and then subjected to hydrophilic treatment. When the capillary structure is an independent component, it may be a material having a relatively higher hydrophilicity after hydrophilic treatment, such as stainless steel subjected to anti-oxidation treatment.

[0043] Embodiment 2

[0044] Embodiment 2 provides a low-resistance microchannel structure for high power density packaging.

[0045] Figure 3 is a cross-sectional schematic diagram of a low-resistance microfluidic channel structure provided in Example 2; Figure 4a It is a top view schematic diagram of the low resistance microfluidic channel structure provided in the second embodiment.

[0046] like Figure 3 and Figure 4a As shown, the low-resistance microfluidic structure for high power density packaging provided in this embodiment includes: a carrier 10, a housing 20 and a heat dissipation microfluidic channel. A chip stack 30 is provided on the carrier 10; the housing 20 is covered on the carrier 10 and accommodates the chip stack 30; the heat dissipation microfluidic channel is surrounded by the carrier 10, the chip stack 30 and the housing 20 and surrounds the chip stack 30, and includes an inlet 24 and an outlet 25 for the coolant to enter and exit, which are arranged on the side of the housing 20 away from the carrier 10, and the inner wall of the microfluidic channel has a hydrophilic surface.

[0047] In this embodiment, the carrier 10 may be, for example, a PCB or other package substrate 11, and the chip stack 30 and the carrier 10 are connected by an interposer. The interposer is provided with a conductive through hole 12 (a through silicon via or a through glass via filled with metal, such as copper), and metal solder balls 13 (such as tin solder balls) may be provided on both sides of the conductive through hole 12. The chip stack 30 is bonded to the first side of one side of the conductive through hole 12 (interposer) by the metal solder balls 13, and the second side of the interposer is connected to the carrier 10. The chip stack 30 may include a plurality of (at least two) layers of chips 31 bonded in sequence, and at least some of the chips 31 are also provided with grooves 33 extending in a planar direction (parallel to the surface of the carrier 10) as microfluidic branches for the flow of coolant. Of course, each chip 31 may be provided with a through silicon via and a pad, and the pad and the through silicon via are provided with metal solder balls 13 for bonding the above-mentioned multiple chips 31.

[0048] Please continue to refer to Figure 3 The shell 20 can be made of a material that is easy to process and suitable for being tightly connected (e.g., bonded) to the surface of the carrier 10. In this embodiment, the shell 20 can be made of silicon, that is, prepared from a silicon wafer by photolithography and etching. The shell 20 can be bowl-shaped, buckled (covered) on the carrier 10 and forming a cavity for accommodating the chip stack 30. It can include a bottom plate portion 21, a side wall portion 22, and a cover plate portion 23. The bottom plate portion 21 is connected to the carrier 10, and it protrudes relative to the side wall portion 22 and is close to the intermediate board, and is arranged to contact the edge of the intermediate board. The side wall portion 22 is connected to the bottom plate portion 21 and is perpendicular to the surface of the carrier 10. The cover plate portion 23 is connected to the side wall portion 22 and is away from the bottom plate portion 21. The cover plate portion 23 can be provided with an inlet 24 and an outlet 25 for the coolant to enter and exit. The inlet 24 and the outlet 25 can be arranged at opposite ends of the cover plate portion 23. Thus, the above-mentioned cavity, inlet 24 and outlet 25 can form a heat dissipation microfluidic channel surrounding the chip stack 30, wherein the space between the side wall portion 22 of the shell 20, the bottom plate portion 21 and the side of the chip stack 30 serves as a microfluidic branch of the heat dissipation microfluidic channel surrounding the chip stack 30, and a channel layer 32 is provided on the top surface of the chip stack 30, and a plurality of grooves 33 are provided on the surface of the channel layer 32 as microfluidic branches covering the surface of the chip stack 30 of the heat dissipation microfluidic channel, and a plurality of grooves 33 extending along the surface of the chip 31 are also provided in the chip stack 30 as microfluidic branches.

[0049] In this embodiment, the channel layer 32 can also be used as a heat sink component to extract the heat of the chip stack 30. The top of the channel layer 32 is in contact with the cover portion 23 of the housing 20. Compared with the first embodiment in which the coolant is pumped into the channel layer 32, the inlet 24 and outlet 25 of the heat dissipation microchannel of this embodiment are opened in the cover portion 23 on both sides directly above the channel layer 32, that is, the inlet 24 and outlet 25 are arranged in the cover portion 23 directly above the bottom plate portion 21, which can reduce the flow resistance. Of course, in other examples of this embodiment, the cavity formed by the housing 20 and the carrier 10 can also be provided with at least two spaced-apart chip stacks 30 for dissipating heat from multiple chip stacks 30 at the same time.

[0050] In particular, in this embodiment, the inner wall of the above-mentioned microchannel has a hydrophilic surface, and the hydrophilic surface is used to improve the wettability (high wettability) of the coolant on the inner wall of the microchannel, thereby reducing the flow resistance of the coolant in the microchannel, and thus reducing the pumping power of the coolant in the microchannel. Among them, after the heat dissipation microchannel is formed, the heat dissipation microchannel can be hydrophilized by physical and / or chemical methods to form a hydrophilic surface in the heat dissipation microchannel. In one example, the physical method can be, for example: oxygen (such as oxygen) plasma treatment is passed into the microchannel, and the inner wall of the microchannel is treated with oxygen plasma to form a hydrophilic surface. In another example, the chemical method can be, for example, including: passing a liquid including a hydrophilic self-assembled monolayer component into the microchannel to form a hydrophilic self-assembled monolayer on the inner wall of the microchannel. Of course, the hydrophilic surface formed above and its properties can match the specific type of coolant, and the coolant can be water, ethanol or Freon, etc. Taking the wetting angle as an example to characterize hydrophilicity, the wetting angle between the coolant and the microchannel surface may be less than 90°.

[0051] In addition, in a preferred example, before packaging to form the microchannel, the outer wall of the chip stack 30 (the outer wall exposed in the cavity) can be hydrophilically treated to further improve the hydrophilicity of the outer wall of the chip stack 30, that is, to improve the wettability of the outer wall of the chip stack 30 by the coolant, thereby helping to reduce resistance and improve the cooling effect.

[0052] Further, such as Figure 4a As shown in the top view, a plurality of capillary structures 25a can be provided at the outlet 25, and the coolant can be guided out (pumped out) from the outlet 25 by the spontaneous climbing of the coolant in the capillary structure 25a, so as to ensure the switching of the coolant in the microchannel under the premise of further reducing the pumping power. The capillary structure 25a can be a through hole with a high aspect ratio (i.e., an elongated shape), and its diameter can be less than XX microns. In one example, Figure 4a As shown, the outlet 25 may be composed of a plurality of capillary structures 25a, that is, all through holes of the outlet 25 are capillary structures. Figure 4bAs shown in the top view, the outlet 25 may be composed of a plurality of capillary structures 25a and a plurality of non-capillary structures 25b (which have a relatively large aspect ratio and cannot form an obvious capillary effect), that is, including the capillary structure 25a and the non-capillary structure 25b, to ensure that the flow rate of the outlet 25 meets the requirements. In other examples, such as Figure 4c As shown in the top view, at least two (for example, two) outlets 25 formed by capillary structures 25a may be provided on the housing 20 (cover plate portion 23) to take into account the flow rate of the outlets 25 while utilizing the capillary effect. The two outlets 25 may be arranged side by side at one end relative to the inlet 24, and the two outlets 25 may maintain the same distance from the inlet 24. It can be understood that in this embodiment, the hydrophilic surface in the capillary structure 25a may further enhance the capillary force of the coolant therein, so that the coolant can quickly climb without resistance, further reducing the resistance of the inlet 24 and the outlet 25, so as to reduce the pumping power.

[0053] It is understandable that the capillary structure 25a of the above-mentioned outlet may be an independent component integrally formed with the shell or embedded in the outlet. The capillary structure integrally formed with the shell (formed by part of the shell) may have a hydrophilicity close to that of the inner wall of the microchannel. For example, if the shell is made of silicon, the shell surface (silicon surface) may be oxidized to form silicon oxide as the inner wall of the microchannel, and then subjected to hydrophilic treatment. When the capillary structure is an independent component, it may be a material having a relatively higher hydrophilicity after hydrophilic treatment, such as stainless steel subjected to anti-oxidation treatment.

[0054] In summary, the low-resistance microfluidic structure for high-power density packaging of the present invention includes: a carrier, a shell and a heat dissipation microfluidic channel. A chip stack is provided on the carrier; the shell cover is provided on the carrier and accommodates the chip stack; the heat dissipation microfluidic channel is surrounded by the carrier, the chip stack and the shell and surrounds the chip stack, and includes an inlet and an outlet for the coolant to enter and exit, which are provided on the side of the shell away from the carrier, and the inner wall of the microfluidic channel has a hydrophilic surface. In the present invention, the inner wall of the microfluidic channel has a hydrophilic surface, and the hydrophilic surface is used to improve the wettability (high wettability) of the coolant on the inner wall of the microfluidic channel, thereby reducing the flow resistance of the coolant in the microfluidic channel, and thus reducing the pumping power of the coolant in the microfluidic channel.

[0055] The above description is only a description of the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention. Any changes or modifications made by a person skilled in the art in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A low-resistance microfluidic structure for high power density packaging, characterized in that: include: A carrier board, on which a chip stack is arranged; A housing, which is disposed on the carrier and accommodates the chip stack; The heat dissipation microchannel is surrounded by the carrier, the chip stack and the shell and surrounds the chip stack, and includes an inlet and an outlet for cooling liquid to enter and exit, which are arranged on the side of the shell away from the carrier. The inner wall of the microchannel has a hydrophilic surface.

2. The low-resistance microchannel structure for high power density packaging according to claim 1, characterized in that: The carrier is an intermediate board, the shell includes a side wall portion connected to the carrier and a cover portion connected to the side wall portion and away from the carrier, and the inlet and the outlet are both arranged in the cover portion directly above the chip stack.

3. The low-resistance microfluidic channel structure for high power density packaging according to claim 1, characterized in that: The carrier and the chip stack are connected by an intermediate layer, and the shell includes a bottom plate portion, a side wall portion and a cover plate portion. The bottom plate portion is connected to the carrier and is close to the intermediate plate, the side wall portion is connected to the bottom plate portion, and the cover plate portion is connected to the side wall portion and is away from the bottom plate portion. The inlet and the outlet are respectively arranged in the cover plate portions on both sides above the chip stack.

4. The low-resistance microchannel structure for high power density packaging according to claim 3, characterized in that: The chip stack includes at least two layers of chips bonded in sequence, and at least part of the chips are provided with microchannels for cooling liquid to flow.

5. The low-resistance microfluidic channel structure for high power density packaging according to any one of claims 2 to 4, characterized in that: A channel layer is also provided on the top surface of the chip stack, and the channel layer is at least partially in contact with the cover plate portion. A plurality of grooves are provided in the channel layer as micro-channels for cooling liquid to flow.

6. The low-resistance microfluidic channel structure for high power density packaging according to claim 1, characterized in that: The outlet includes a plurality of capillary structures, and the capillary structures are integrally formed with the housing or are independent components embedded in the outlet.

7. The low-resistance microchannel structure for high power density packaging according to claim 6, characterized in that: The shell is provided with an inlet and at least two outlets, and the at least two outlets are arranged in parallel at one end opposite to the inlet.

8. The low-resistance microchannel structure for high power density packaging according to claim 1, characterized in that: After the heat dissipation micro-channel is formed, a hydrophilic treatment is performed on the heat dissipation micro-channel by a physical and / or chemical method to form the hydrophilic surface in the heat dissipation micro-channel.

9. The low-resistance microfluidic channel structure for high power density packaging according to claim 8, characterized in that: The hydrophilicity of the outer wall of the chip stack in the microfluidic channel is greater than or equal to the hydrophilicity of the inner wall of the housing.

10. The low-resistance microchannel structure for high power density packaging according to claim 8, characterized in that: The physical method includes treating the inner wall of the heat dissipation microchannel with oxygen plasma, and the chemical method includes forming a hydrophilic self-assembled monolayer on the inner wall of the heat dissipation microchannel.

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