Disclosure of Invention
In view of this, embodiments of the present invention provide a method for manufacturing an insulating substrate and a method for packaging a power device, where when the insulating substrate manufactured by the method for manufacturing an insulating substrate is used for packaging a power device, the number of layers of a material through which heat generated by the power device passes from a junction to a heat sink may be reduced, so as to reduce the junction-to-case thermal resistance of a power device packaging structure, thereby enhancing the heat dissipation effect of the power device.
In order to achieve the above purpose, the embodiments of the present invention provide the following technical solutions:
the first aspect of the embodiments of the present invention discloses a method for manufacturing an insulating substrate, including:
cutting a prepared heat-conducting plate according to a groove die with a first preset size to obtain a first groove, wherein the opening direction of the first groove is the upper surface of the heat-conducting plate;
printing an insulating material in the first groove;
etching the insulating material in the first groove according to a second preset size to form a second groove, wherein the second preset size is smaller than the first preset size;
placing a microchannel mold in the second groove, wherein the upper surface of the microchannel mold faces the opening direction of the second groove;
printing an insulating material on the upper surface of the micro-channel mold, and forming an insulating layer with the insulating material in the first groove;
depositing a first heat conduction material with a first preset thickness on the upper surface of the heat conduction plate to close the heat conduction plate to form a first heat conduction layer;
removing the microchannel mold;
and injecting cooling liquid into the micro-channel after the micro-channel mould is removed to obtain the insulating substrate integrated with the heat dissipation micro-channel.
Optionally, etching the insulating material in the first groove according to a second preset size, and after forming a second groove, the method further includes:
depositing a second thermally conductive material within the second recess;
cutting the second heat conduction material in the second groove according to a third preset size to form a third groove, wherein the third preset size is smaller than the second preset size;
placing a micro-channel mold in the third groove, wherein the upper surface of the micro-channel mold faces the opening direction of the third groove;
depositing a second heat conduction material with a second preset thickness on the upper surface of the heat conduction plate to close the heat conduction plate;
removing a second preset thickness of second heat conduction material deposited at the position of the insulating material to form a second heat conduction layer with the second heat conduction material in the second groove;
printing an insulating material on the surface of the second heat-conducting layer, and forming an insulating layer with the insulating material in the first groove;
depositing a third heat conduction material with a third preset thickness on the surface of the insulating layer to close the heat conduction plate to form a first heat conduction layer;
removing the microchannel mold;
and injecting cooling liquid into the micro-channel after the micro-channel mould is removed to obtain the insulating substrate integrated with the heat dissipation micro-channel.
Optionally, an insulating material is printed on the upper surface of the microchannel mold according to a fourth preset thickness, where the fourth preset thickness is smaller than the shortest distance from the groove bottom of the first groove to the lower surface of the heat conducting plate.
Optionally, cutting one or more first grooves on the heat-conducting plate;
if a second groove is formed corresponding to the first groove, placing a square, snake-shaped, conical or round micro-channel mould in the second groove;
if a plurality of second grooves are formed corresponding to the first grooves, the same or different micro-channel molds in the shapes of squares, snakes, cones and circles are placed in each second groove.
Optionally, cutting one or more first grooves on the heat-conducting plate;
if a third groove is formed corresponding to the first groove, placing a square, snake-shaped, conical or round micro-channel mould in the third groove;
if the number of the formed third grooves is multiple, the same or different micro-channel mold in the square shape, the snake shape, the conical shape and the circular shape is placed in each third groove.
Optionally, a heat-conducting plate made of copper or a heat-conducting plate made of aluminum is prepared.
Optionally, a ceramic or aluminum nitride insulating material is printed.
Optionally, copper or aluminum with a first preset thickness is deposited on the upper surface of the heat conducting plate, so that the heat conducting plate is closed to form a first heat conducting layer.
Optionally, depositing copper or aluminum with a second preset thickness on the upper surface of the heat conducting plate to close the heat conducting plate;
removing the copper or aluminum deposited at the position of the insulating material to form a second heat conduction layer with the heat conduction material in the second groove;
and depositing copper or aluminum with a third preset thickness on the surface of the insulating layer to close the heat conducting plate to form a first heat conducting layer.
The second aspect of the embodiments of the present invention discloses a power device packaging method, including:
and welding an insulating substrate integrated with a heat dissipation micro-channel on the first surface and/or the second surface of the chip, wherein the insulating substrate integrated with the heat dissipation micro-channel is prepared according to the preparation method of the insulating substrate disclosed by the first aspect of the embodiment of the invention.
Based on the preparation method of the insulating substrate provided by the embodiment of the invention, the preparation method of the insulating substrate comprises the steps of cutting a first groove on a heat conducting plate according to a groove mould with a first preset size, printing an insulating material in the first groove obtained by cutting, etching the insulating material in the first groove according to a second preset size to form a second groove, placing a microchannel mould in the second groove to print the insulating material on the upper surface of the microchannel mould, enabling the insulating material printed on the upper surface of the microchannel mould and the insulating material in the first groove to form an insulating layer, depositing a first heat conducting material with a first preset thickness on the upper surface of the heat conducting plate to close the heat conducting plate, enabling the heat conducting plate and the first heat conducting material deposited on the upper surface of the heat conducting plate to form a first heat conducting layer, removing the microchannel mould, and injecting a cooling liquid into a microchannel formed by the microchannel mould to obtain the insulating substrate integrated with the heat dissipation microchannel.
In the embodiment of the invention, heat generated by the power device can reach the micro-channel only through the first heat conduction layer and the insulating layer of the insulating substrate integrated with the heat dissipation micro-channel, namely, the heat can reach the micro-channel only through two layers of materials, and then the heat is dissipated by using the cooling liquid in the micro-channel, so that the number of layers of the materials through which the heat passes is greatly reduced, and the crusting thermal resistance of the packaging structure of the power device is effectively reduced; meanwhile, the radiating micro-channel is integrated on the insulating substrate in an additive printing mode, so that the preparation is flexible, and the size of a power device packaging structure is reduced.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, but the present application may be practiced in other ways than those described herein, and it will be apparent to those of ordinary skill in the art that the present application is not limited to the specific embodiments disclosed below.
Next, the present invention will be described in detail with reference to the drawings, wherein the cross-sectional views illustrating the structure of the device are not enlarged partially according to the general scale for convenience of illustration when describing the embodiments of the present invention, and the drawings are only examples, which should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.
Referring to fig. 1 to 18, embodiments of the present invention provide a method for manufacturing an insulating substrate and an insulating substrate integrated with a heat dissipation micro-channel formed by the method for manufacturing the insulating substrate.
As shown in fig. 1, the insulating substrate integrated with heat dissipation micro-channel comprises a first heat conduction layer 100, an insulating layer and a micro-channel 200. The micro-channel 200 has a channel inlet connected to a water inlet pipe of the external water-cooling circulation system and a channel outlet connected to a water outlet pipe of the external water-cooling circulation system, so as to realize the injection of the cooling liquid and the control of the circulation flow under the control of the external water-cooling circulation system.
The shape and size of the microchannel 200 are determined by the microchannel die 3, and those skilled in the art can select different microchannel dies 3 according to actual needs to form the desired microchannel 200.
An embodiment of the present invention provides a method for manufacturing an insulating substrate, as shown in fig. 2, including the following steps:
s11: a first groove is cut in the upper surface of the prepared heat-conducting plate 1.
After S11 is performed, a cross-sectional view as shown in fig. 3 is formed.
The first groove is cut according to a groove die with a first preset size, and the first preset size is smaller than the size of the heat conducting plate 1.
The heat conducting plate 1 can be a metal plate with good heat conducting and electric conducting properties.
In an embodiment of the present invention, the heat conducting plate 1 may be a copper heat conducting plate or an aluminum heat conducting plate, and the copper heat conducting plate or the aluminum heat conducting plate has high heat conductivity, so that when the heat conducting plate 1 conducts heat, the heat conducting speed is high, and the heat conducting resistance is small. Meanwhile, the copper heat conduction plate or the aluminum heat conduction plate has good electric conductivity and can conduct electricity. The first groove can be cut from any position of the upper surface of the heat conducting plate 1, so that the opening direction of the first groove is the upper surface of the heat conducting plate 1.
The cutting means may be conventional cutting means, such as laser cutting.
The upper surface of the heat conductive plate 1 may be any one surface of the heat conductive plate 1.
The size and shape of the groove die with the first preset size can be selected according to actual needs.
In one embodiment of the invention, the first groove is cut according to the centre line of the plate 1, so that it is located off the centre line of the plate 1.
S12: and printing an insulating material 2 in the cut first groove.
After S12 is performed, a cross-sectional view is formed as shown in fig. 4.
The height of the insulating material 2 printed in the first recess is equal to the depth of the first recess.
In one embodiment of the invention, the height of the insulating material 2 printed in the first recess may not be equal to the depth of the first recess.
The printing mode is preferably 3D additive printing.
In an embodiment of the present invention, the insulating material 2 may be ceramic or aluminum nitride, and the ceramic insulating material or the aluminum nitride insulating material is printed by 3D additive printing, so that the insulating material 2 forms a ceramic insulating layer or an aluminum nitride insulating layer.
The ceramic insulating layer or the aluminum nitride insulating layer has good heat conducting property, and is convenient for heat conduction. Meanwhile, the existence of the insulating layer can well isolate the cooling liquid from the heat conducting plate 1, so that the insulation of the cooling liquid and the charged part of the heat conducting plate 1 is ensured, the deionized cooling liquid is not needed, and the preparation cost is reduced.
S13: and etching the printed insulating material 2 according to a second preset size to form a second groove.
After S13 is performed, a cross-sectional view is formed as shown in fig. 5.
Wherein, the second preset size is smaller than the first preset size, and the periphery of the second groove formed by immediate etching comprises a layer of insulating material 2.
The thickness of the insulating material 2 is the same throughout the periphery of the second recess.
In an embodiment of the present invention, the thickness of the insulating material 2 at the periphery of the second groove may be different, and those skilled in the art may perform etching according to actual needs.
The insulating material 2 may be etched by dry etching or wet etching, such as plasma etching.
S14: in said second groove a microchannel mold 3 is placed.
After S14 is performed, a cross-sectional view shown in fig. 6 is formed.
The upper surface of the microchannel die 3 faces the opening direction of the second groove.
It is noted that only one of said microchannel dies 3 need to be placed in one of said second recesses.
According to the steps S11 to S14, one second groove is formed corresponding to one first groove, and a plurality of second grooves are formed corresponding to a plurality of first grooves.
In one embodiment of the invention, in forming one of said second grooves, a microchannel mold 3 of one of a square, serpentine, conical, circular shape is placed in said second groove.
For example, a square microchannel die 3 is selected to be placed in the second recess. In forming a plurality of the second grooves, one of the same or different square, serpentine, tapered, and circular micro-channel molds 3 is placed in each of the second grooves.
Specifically, the second grooves may be used for accommodating microchannel molds 3 of the same shape, or may be used for accommodating microchannel molds 3 of different shapes.
For example, three first grooves are cut on the heat conducting plate 1, three second grooves are correspondingly formed, square microchannel molds 3 can be placed in all the three second grooves, circular microchannel molds 3 can be placed in all the three second grooves, a square microchannel mold 3 can be placed in one second groove, a circular microchannel mold 3 can be placed in one second groove, and a serpentine microchannel mold 3 can be placed in one second groove.
S15: and printing an insulating material 2 on the upper surface of the micro-channel mold 3 to form an insulating layer with the insulating material 2 in the first groove.
After S15 is performed, a cross-sectional view shown in fig. 7 is formed.
The thickness of the insulating material 2 printed on the upper surface of the micro-channel die 3 is the same as that of the insulating material 2 in the first groove, namely the thickness of the insulating layer is the same at all positions.
Of course, the thickness of the insulating material 2 printed on the upper surface of the microchannel mold 3 may be different from the thickness of the insulating material 2 in the first groove. The thickness of the insulating material 2, for example printed on the upper surface of the microchannel die 3, is smaller than the thickness of the insulating material 2 in the first recess.
In one embodiment of the invention, the insulating material 2 is printed on the upper surface of the microchannel die 3 according to a fourth preset thickness, which is smaller than the shortest distance from the bottom of the first groove to the lower surface of the heat-conducting plate 1.
S16: depositing a first heat conduction material 4 with a first preset thickness on the upper surface of the heat conduction plate 1 to close the heat conduction plate 1, so as to form a first heat conduction layer 100.
After S16 is performed, a cross-sectional view is formed as shown in fig. 8.
It should be noted that depositing the first heat conductive material 4 on the upper surface of the heat conducting plate 1 includes depositing the first heat conductive material 4 on the surface of the insulating layer to close the heat conducting plate 1.
The first heat conductive material 4 and the heat conductive plate 1 may be made of the same material or different materials.
The first preset thickness is smaller than the shortest distance from the bottom of the first groove to the lower surface of the heat conducting plate 1.
In one embodiment of the present invention, the sum of the thickness of the insulating layer on the upper surface of the microchannel mold 3 and the thickness of the first heat conductive material 4 on the upper surface of the insulating layer is smaller than the shortest distance from the groove bottom of the first groove to the lower surface of the heat conductive plate 1.
The smaller the first predetermined thickness is, the thinner the first heat conduction layer 100 is formed, and the smaller the resistance is in heat conduction.
The heat conducting plate 1 and the first heat conducting material 4 deposited on the upper surface of the heat conducting plate 1 can be made of materials with good heat conducting and electric conducting properties, so that the first heat conducting layer 100 can conduct heat and electricity.
The deposition method of the first thermal conductive material 4 may adopt a conventional deposition method, such as chemical vapor deposition, physical vapor deposition, evaporation, etc., and of course, other deposition methods may also be adopted, which is not limited herein.
In one embodiment of the present invention, the first heat conducting material 4 deposited on the upper surface of the heat conducting plate 1 by a first preset thickness is copper or aluminum, and the deposited copper or aluminum closes the heat conducting plate 1 to form the first heat conducting layer 100. Wherein the heat conductive plate 1 and the copper or aluminum deposited on the upper surface of the heat conductive plate 1 form the first heat conductive layer 100. Specifically, if the heat-conducting plate 1 is a heat-conducting plate 1 of copper, copper is also selected as the first heat-conducting material 4 to form the first heat-conducting layer 100 of copper, and if the heat-conducting plate 1 is a heat-conducting plate 1 of aluminum, aluminum is also selected as the first heat-conducting material 4 to form the first heat-conducting layer 100 of aluminum.
Through being in 1 upper surface deposit copper or aluminium of heat-conducting plate, the first heat-conducting layer 100 of the copper or the first heat-conducting layer 100 of aluminium of formation can not only realize quick heat conduction, but also can electrically conduct, has improved insulating substrate's suitability.
S17: and removing the microchannel mold 3, forming the microchannel 200 in the accommodating space of the microchannel mold 3, and injecting cooling liquid into the microchannel 200 to obtain the insulating substrate integrated with the heat dissipation microchannel.
After the deposition operation of S16 is performed, the first thermal conductive material to be deposited is cooled, and other materials molded based on the microchannel mold 3 are cooled, a demolding operation is performed S17 to separate the heat dissipation microchannel integrated on the insulating substrate from the microchannel mold 3. Specific means of separation include venting or removal or corrosion venting. The microchannel mold 3 may also be removed by a conventional demolding method.
After removing the microchannel mold 3, when the insulating substrate is used, a cooling liquid is injected into the microchannel 200 through an external water cooling circulation system, and the flow of the cooling liquid in the microchannel 200 is controlled.
After S17 is performed, a cross-sectional view shown in fig. 9 is formed.
It should be noted that after the insulating substrate integrated with the heat dissipation micro-channel is prepared according to the method shown in fig. 2, a layer of insulating material is further required to cover the surface of the insulating substrate to ensure that the whole insulating substrate is in an insulating state.
In the preparation method of the insulating substrate disclosed in the embodiment of the present invention, a first groove is cut on a heat conducting plate 1, an insulating material 2 is printed in the first groove obtained by cutting, the insulating material 2 in the first groove is etched to form a second groove, then a microchannel mold 3 is placed in the second groove to print the insulating material 2 on the upper surface of the microchannel mold 3, so that the insulating material 2 printed on the upper surface of the microchannel mold 3 and the insulating material 2 in the first groove form an insulating layer, then a first heat conducting material 4 with a first preset thickness is deposited on the upper surface of the heat conducting plate 1 to close the heat conducting plate 1, so that the heat conducting plate 1 and the first heat conducting material 4 with the first preset thickness deposited on the upper surface of the heat conducting plate 1 form a first heat conducting layer 100, then the microchannel mold 3 is removed, and a cooling liquid is injected into the microchannel 200 formed by the microchannel mold 3 to obtain the insulating substrate integrated with a heat dissipation microchannel.
In the embodiment of the present invention, the preparation of the insulating substrate integrated with the heat dissipation micro-channel is realized by the preparation method of forming the first heat conduction layer 100, the insulating layer and the micro-channel 200 on the insulating substrate and injecting the cooling liquid into the micro-channel 200. The insulating substrate integrated with the heat dissipation micro-channel can be directly welded with a power device to form a power device packaging structure. The heat generated by the power device can reach the micro-channel 200 only through the first heat conduction layer 100 and the insulating layer of the insulating substrate integrated with the heat dissipation micro-channel, namely the heat can reach the micro-channel 200 only through two layers of materials, and then the heat is dissipated by using the cooling liquid in the micro-channel 200, so that the number of layers of the materials through which the heat passes is greatly reduced, and the crusting thermal resistance of the packaging structure of the power device is effectively reduced; meanwhile, the radiating micro-channel is integrated on the insulating substrate in an additive printing mode, so that the preparation is flexible, and the size of a power device packaging structure is reduced.
The embodiment of the invention also discloses another preparation method of the insulating substrate, which comprises the following steps of:
s21: a first groove is cut in the upper surface of the preliminary heat-conducting plate 1.
The implementation of step S21 is the same as the implementation of step S11, and reference is made to the above description for details, which are not repeated herein.
S22: and printing an insulating material 2 in the cut first groove.
The implementation manner of step S22 is the same as that of step S12, and reference is made to the above description for details, which are not repeated herein.
S23: and etching the printed insulating material 2 according to a second preset size to form a second groove.
The implementation manner of step S23 is the same as the implementation manner of step S13, and reference is made to the above description for details, which are not described herein again.
S24: a second heat conducting material 5 is deposited in the second recess.
After S24 is performed, a cross-sectional view is formed as shown in fig. 11.
The height of the second heat conductive material 5 is the same as the height of the insulating material 2 in the second groove.
In one embodiment of the present invention, the height of the second thermal conductive material 5 and the height of the insulating material 2 in the second groove may not be the same.
S25: cutting the second heat conducting material 5 deposited in said second recess.
After S25 is performed, a cross-sectional view shown in fig. 12 is formed.
And cutting the second heat conduction material 5 in the second groove according to a third preset size to form a third groove.
Wherein, the third preset size is smaller than the second preset size, that is, the periphery of the third groove formed by cutting comprises a layer of the second heat conduction material 5.
The thickness of the second heat conduction material 5 at the periphery of the third groove is the same at all positions.
In an embodiment of the present invention, the thickness of the second heat conduction material 5 at various places around the periphery of the third groove may be different, and those skilled in the art can select the thickness according to actual needs.
S26: in which third grooves the microchannel mold 3 is placed.
The upper surface of the microchannel die 3 faces the opening direction of the third groove.
After S26 is performed, a cross-sectional view shown in fig. 13 is formed.
According to the steps S21 to S25, one third groove is formed corresponding to one first groove, and a plurality of third grooves are formed corresponding to a plurality of first grooves.
It should be noted that the microchannel mold 3 placed in the third groove is the same as the microchannel mold 3 placed in the second groove in the embodiment disclosed in fig. 2, and the description thereof is omitted.
S27: and depositing a second heat conduction material 5 with a second preset thickness on the upper surface of the heat conduction plate 1.
After S27 is performed, a cross-sectional view is formed as shown in fig. 14.
Depositing a second thermal conductive material 5 on the upper surface of the thermal conductive plate 1 further comprises depositing a second thermal conductive material 5 on the upper surface of the microchannel mold 3, the upper surface of the second thermal conductive material 5 in the second groove, and the upper surface of the insulating material 2, so that the thermal conductive plate 1 is closed. The upper surfaces face the opening direction of the third groove. The second preset thickness is smaller than the shortest distance from the bottom of the first groove to the lower surface of the heat conducting plate 1.
In one embodiment of the present invention, the thickness of the second heat conducting material 5 deposited on the upper surface of the microchannel die 3 is smaller than the shortest distance from the bottom of the first groove to the lower surface of the heat conducting plate 1.
In one embodiment of the present invention, the second heat conductive material 5 of the second preset thickness deposited on the upper surface of the heat conductive plate 1 is copper or aluminum, which closes the heat conductive plate 1. And further removing the copper or the aluminum deposited at the position of the insulating material 2 by an etching process to obtain a second heat conduction layer of the copper or the second heat conduction layer of the aluminum.
S28: the second heat conductive material 5 is etched.
After S28 is executed, a cross-sectional view is formed as shown in fig. 15.
And removing the second heat conduction material 5 deposited on the upper surface of the insulating material 2 by means of etching to expose the insulating material 2.
It should be noted that after the etching is completed, the second heat conduction material 5 on the periphery of the microchannel mold 3 forms a closed second heat conduction layer, and the thickness of the second heat conduction layer is the same everywhere.
Of course, the thickness of the second heat conduction layer can be different from place to place.
S29: and printing the insulating material 2 on the surface of the second heat-conducting layer.
After S29 is executed, a cross-sectional view shown in fig. 16 is formed.
And printing the insulating material 2 on the surface of the second heat conduction layer corresponding to the exposed position of the insulating material 2, so that the insulating material 2 printed on the surface of the second heat conduction layer and the insulating material 2 in the first groove form an insulating layer.
The thickness of the insulating layer is the same everywhere.
Of course, the thickness of the insulating layer may be different from place to place.
In one embodiment of the present invention, the thickness of the second heat conducting layer is smaller than the thickness of the insulating layer.
S30: a third thermally conductive material 6 is deposited on the surface of the insulating layer.
After S30 is executed, a cross-sectional view is formed as shown in fig. 17.
And depositing a third heat conduction material 6 with a third preset thickness on the surface of the insulating layer to close the heat conduction plate 1. The heat conducting plate 1, the second heat conducting material 5 with the second preset thickness and the third heat conducting material 6 with the third preset thickness deposited on the heat conducting plate 1 jointly form a first heat conducting layer 100.
The third preset thickness is smaller than the shortest distance from the bottom of the first groove to the lower surface of the heat conducting plate 1.
In one embodiment of the present invention, the thickness of the third thermal conductive material deposited on the upper surface of the insulating layer is smaller than the shortest distance from the bottom of the first groove to the lower surface of the thermal conductive plate 1; or the sum of the thickness of the second heat conduction layer deposited on the upper surface of the micro-channel mold 3, the thickness of the insulation layer on the upper surface of the second heat conduction layer and the thickness of the third heat conduction material 6 on the upper surface of the insulation layer is smaller than the shortest distance from the bottom of the first groove to the lower surface of the heat conduction plate 1.
The upper surface of the second heat conduction layer and the upper surface of the insulation layer face the opening direction of the third groove.
In one embodiment of the invention, the third heat conducting material 6 deposited on the surface of the insulating layer is copper or aluminum, which closes the heat conducting plate 1 and finally forms the first heat conducting layer 100 with the cut heat conducting plate 1.
S31: the microchannel mold 3 is removed.
The specific implementation of S31 is the same as S17.
After S31 is executed, a cross-sectional view shown in fig. 18 is formed.
Removing the microchannel mold 3 placed in the third groove, the accommodating space of the microchannel mold 3 forming the microchannel 200. A cooling liquid is injected into the microchannel 200, thereby obtaining an insulating substrate integrated with a heat dissipation microchannel.
It should be noted that after the insulating substrate integrated with the heat dissipation micro-channel is prepared according to the method shown in fig. 10, a layer of insulating material is further required to cover the surface of the insulating substrate to ensure that the whole insulating substrate is in an insulating state.
In the preparation method of the insulating substrate disclosed by the embodiment of the invention, the heat of the insulating layer is quickly conducted into the micro-channel through the formed first heat conducting layer 100 and the second heat conducting layer. Meanwhile, the second heat conduction layer can separate the insulating layer from the cooling liquid so as to protect the insulating layer from being corroded by the cooling liquid and avoid the insulating layer from being lost by the cooling liquid and further causing failure.
Furthermore, heat generated by the power device can reach the micro-channel 200 through the first heat conduction layer 100, the insulating layer and the second heat conduction layer of the insulating substrate integrated with the heat dissipation micro-channel, namely the heat can reach the micro-channel 200 through three layers of materials, and then the heat is dissipated by using cooling liquid in the micro-channel 200, so that the number of layers of materials through which the heat passes is greatly reduced, and the crusting thermal resistance of the packaging structure of the power device is effectively reduced; meanwhile, the radiating micro-channel is integrated on the insulating substrate in an additive printing mode, so that the preparation is flexible, and the size of a power device packaging structure is reduced.
In one embodiment of the present invention, the insulating substrate integrated with 5 heat dissipation micro-channels using a rectangular micro-channel mold 3 is finally obtained by the manufacturing method according to fig. 10 as shown in fig. 19 to 30. The method specifically comprises the following steps:
1. the heat-conducting plate 1 shown in fig. 19 is prepared.
2. The structure of fig. 20 is obtained by cutting 5 first grooves on the upper surface of the plate 1.
3. The insulating material 2 is printed in the 5 first grooves obtained by cutting, resulting in the structure of fig. 21.
4. And etching the insulating material 2 in the 5 first grooves to form 5 second grooves, thereby obtaining the structure shown in fig. 22.
5. Depositing a second heat conducting material 5 in 5 of said second recesses, resulting in the structure of fig. 23.
6. And cutting 5 second heat conduction materials 5 in the second grooves to form 5 third grooves, so as to obtain the structure shown in the figure 24.
7. In 5 of said third grooves a rectangular microchannel die 3 is placed, resulting in the structure of fig. 25.
8. Depositing a second heat conducting material 5 on the upper surface of the heat conducting plate 1, so that the heat conducting plate 1 is closed, and obtaining the structure of fig. 26.
9. The second heat conducting material 5 on the upper surface of the insulating material 2 is removed by etching to form a closed second heat conducting layer, and the upper surface of the insulating material 2 is exposed, so that the structure of fig. 27 is obtained.
10. And printing an insulating material 2 on the surface of the second heat-conducting layer to form an insulating layer, so as to obtain the structure shown in fig. 28.
11. Depositing a third heat conducting material 6 on the surface of the insulating layer to close the heat conducting plate 1, so as to obtain the structure shown in fig. 29.
12. Removing the rectangular microchannel mold 3, and injecting a cooling liquid into the accommodating space formed by the rectangular microchannel mold 3 to form the insulating substrate integrated with the heat dissipation microchannel, thereby obtaining the structure of fig. 30.
By integrating 5 heat dissipation micro-channels on the insulating substrate, when a power device conducts heat to the insulating substrate, cooling liquid in the 5 heat dissipation micro-channels can quickly take away the heat through circulating flow; and the 5 heat dissipation micro-channels are arranged at positions close to the positions welded with the power device, heat generated by the power device can reach the 5 micro-channels 200 in a shorter time, so that the heat is taken away by cooling liquid in the 5 micro-channels 200, and the heat dissipation of the power device is further accelerated.
The embodiment of the invention also provides a power device packaging method, which comprises the following steps:
an insulating substrate integrated with a heat dissipation micro-channel is soldered on the first surface or the second surface of the chip 300.
The first and second surfaces are opposing surfaces.
As shown in fig. 31, the insulating substrate integrated with the heat dissipation micro-channel obtained by the preparation method of fig. 2 is bonded to the first surface or the second surface of the chip 300. The heat dissipation micro-channel comprises the first heat conduction layer 100, the insulation layer and the micro-channel 200, wherein the insulation layer is formed by the insulation material 2. When the chip 300 generates heat, the heat is conducted from the first surface or the second surface of the chip 300 to the first heat conducting layer 100 of the insulating substrate, and then conducted to the micro-channel 200 through the first heat conducting layer 100, so that the chip 300 is cooled by the cooling liquid circulating in the micro-channel 200.
Alternatively, as shown in fig. 32, the insulating substrate integrated with a heat dissipation microchannel obtained by the preparation method of fig. 10 is bonded to the first surface or the second surface of the chip 300. The heat dissipation micro-channel comprises the first heat conduction layer 100, the insulation layer, the second heat conduction layer and the micro-channel 200, wherein the insulation layer is formed by the insulation material 2, and the second heat conduction layer is formed by the second heat conduction material 5. When the chip 300 generates heat, the heat is conducted from the first surface or the second surface of the chip 300 to the first heat conducting layer 100, then conducted to the second heat conducting layer through the first heat conducting layer 100, and finally conducted to the micro-channel 200 from the second heat conducting layer, so as to dissipate the heat of the chip 300 through the cooling liquid circulating in the micro-channel 200.
It should be noted that, one or more micro channels 200 may be integrated on the insulating substrate, as shown in fig. 33, a chip 300 is welded to an insulating substrate 400 integrated with 5 square heat dissipation micro channels, and the power device package structure may enable heat of the chip 300 to be quickly dissipated through a coolant circulating through the 5 heat dissipation micro channels. Of course, those skilled in the art can select the insulating substrate 400 integrated with a certain number of heat dissipation micro-channels to be soldered to the chip 300 according to actual needs.
By adopting the power device packaging method of welding the insulating substrate on the first surface or the second surface of the chip 300, the obtained power device packaging structure has less layers of materials when radiating, and the crusting thermal resistance of the power device packaging structure is effectively reduced. Meanwhile, the insulating substrate adopted by the power device packaging structure integrates the heat dissipation micro-channel integration in an additive printing mode, a radiator does not need to be welded on the surface of the insulating substrate to dissipate heat of the chip 300, and the size of the power device packaging structure is reduced.
The embodiment of the invention also provides another power device packaging method, which comprises the following steps:
an insulating substrate integrated with a heat dissipation micro-channel is welded on both the first surface and the second surface of the chip 300.
The first and second surfaces are opposing surfaces.
The welding mode of the chip 300 and the insulating substrate specifically includes: as shown in fig. 34, the insulating substrate integrated with the heat dissipation micro-channel obtained by the preparation method of fig. 2 is bonded to the first surface and the second surface of the chip 300; alternatively, as shown in fig. 35, bonding the insulating substrate integrated with the heat dissipation micro-channel prepared according to the method of fig. 10 on the first surface and the second surface of the chip 300; alternatively, a heat sink microchannel-integrated insulating substrate prepared according to the method of fig. 2 is bonded to a first surface of the chip 300, and a heat sink microchannel-integrated insulating substrate prepared according to the method of fig. 10 is bonded to a second surface of the chip 300.
In one embodiment of the present invention, when the insulating substrate integrated with heat dissipation micro-channels obtained by the manufacturing method of fig. 2 is used for soldering, the heat dissipation micro-channels comprise a first heat conduction layer of copper, an insulating layer of aluminum nitride, and micro-channels 200, and the cooling liquid is glycol-type cooling liquid; when the insulating substrate integrated with the heat dissipation micro-channel obtained by the preparation method of fig. 10 is used for welding, the heat dissipation micro-channel comprises a first heat conduction layer of copper, an insulating layer of aluminum nitride, a second heat conduction layer of copper and a micro-channel 200, and the cooling liquid adopts glycol type cooling liquid.
In an embodiment of the present invention, when the insulating substrate integrated with the heat dissipation micro channel obtained by the preparation method shown in fig. 10 is welded on the first surface and the second surface of the chip 300, and the heat dissipation micro channel is a first heat conduction layer of copper, an insulating layer of aluminum nitride, and a second heat conduction layer of copper, the chip and the package structure thereof are subjected to steady-state thermal characteristic simulation by testing and using a Finite Element Method (FEM), and the calculated junction-to-shell thermal resistance can be reduced to 32% of that of the conventional power device package structure.
The first surface and the second surface of the chip 300 are respectively welded and integrated with the heat dissipation micro-channel insulating substrate, so that the power device packaging structure can dissipate heat from two sides at the same time, the heat dissipation speed is higher, and the heat dissipation efficiency is higher.
It should be noted that in the description of the present application, it should be understood that the terms "upper", "lower", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, which are only used for convenience of description and simplification of the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present application. When a component is referred to as being "connected" to another component, it can be directly connected to the other component or intervening components may also be present.
It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising a … …" does not exclude the presence of another identical element in an article or apparatus that comprises the element.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.