Semiconductor packaging structure and packaging method of semiconductor packaging structure

Abstract

The present invention provides a semiconductor packaging structure and a packaging method for the semiconductor packaging structure, wherein the semiconductor packaging structure comprises: a first heat sink; a bar; a second heat sink, wherein the second heat sink comprises: an insulating heat conductive layer; a first conductive layer and a second conductive layer; a first welding layer; a first insulating layer; a first electrode sheet; a second insulating layer; and a second electrode sheet. The reliability of the semiconductor packaging structure is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a semiconductor packaging structure and a packaging method for the semiconductor packaging structure. Background Art

[0002] A typical structure of a high-power semiconductor bar is a conduction-cooled laser, which can avoid the risk of liquid leakage in industrial equipment of a liquid-cooled bar laser. A high-power semiconductor bar and a heat sink are packaged together to form a semiconductor package structure.

[0003] However, the semiconductor packaging structure of the related art has the problem of poor reliability. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is how to improve the reliability of a semiconductor packaging structure, thereby providing a semiconductor packaging structure and a packaging method for the semiconductor packaging structure.

[0005] The present invention provides a semiconductor packaging structure, comprising: a first heat sink; a bar located on one side of a partial area of ​​the first heat sink; a second heat sink located between the first heat sink and the bar, the second heat sink comprising: an insulating heat-conducting layer, the thermal conductivity of the insulating heat-conducting layer is greater than the thermal conductivity of the bar, and the thermal expansion coefficient of the insulating heat-conducting layer is less than the thermal expansion coefficient of the bar; a first conductive layer and a second conductive layer, the first conductive layer is located on one side surface of the insulating heat-conducting layer in the thickness direction, and the second conductive layer is located on the other side surface of the insulating heat-conducting layer in the thickness direction; a first welding layer, located The first welding layer is between the bar and the second heat sink and in contact with the bar and the second heat sink, and the material of the first welding layer is hard solder; the first insulating layer is located on one side of a partial area of ​​the first heat sink and on the side of the second heat sink; the first electrode sheet is located on the side of the first insulating layer away from the first heat sink and is electrically connected to the side surface of the first heat sink facing the bar; the second insulating layer is located on the side of the first electrode sheet away from the first insulating layer; the second electrode sheet is located on the side of the second insulating layer away from the first electrode sheet and extends to the side surface of the bar away from the second heat sink.

[0006] Optionally, the material of the insulating heat-conducting layer includes aluminum nitride, and the materials of the first conductive layer and the second conductive layer include copper.

[0007] Optionally, the thickness of the insulating heat-conducting layer is 100 μm to 400 μm; the thickness of the first conductive layer is 25 μm to 100 μm; and the thickness of the second conductive layer is 25 μm to 100 μm.

[0008] Optionally, the material of the first welding layer includes gold-tin solder.

[0009] Optionally, the thickness of the first welding layer is 5 μm to 20 μm.

[0010] Optionally, the bar includes: a semiconductor substrate; a first confinement layer, a first waveguide layer, an active layer, a second waveguide layer and a second confinement layer stacked in sequence and located on one side of the semiconductor substrate; a front electrode located on the side of the second confinement layer away from the active layer; a back electrode located on the side of the semiconductor substrate away from the active layer; wherein the front electrode is located between the back electrode and the first heat sink; wherein the first electrode sheet is a positive electrode sheet and the second electrode sheet is a negative electrode sheet.

[0011] Optionally, it also includes: a second welding layer located between the first heat sink and the second heat sink, and the material of the second welding layer includes soft solder.

[0012] Optionally, the thickness of the second welding layer is greater than the thickness of the first welding layer.

[0013] Optionally, the thickness of the second welding layer is 10 microns to 50 microns.

[0014] Optionally, the method further includes: a third heat sink, which is located on a side of the second electrode sheet away from the second insulating layer and is electrically connected to the second electrode sheet.

[0015] Optionally, it further includes: a cooling structure, which is grounded; wherein a side surface of the first heat sink facing away from the bar is in contact with the cooling structure.

[0016] Optionally, the number of the bar strips, the second heat sink, and the first welding layer are all multiple; the multiple bar strips are arranged at intervals along a first direction parallel to the surface of the first heat sink, and the multiple second heat sinks are arranged at intervals along the first direction; wherein, the size of the bar strips along the first direction is 3mm~3.3mm, and the size of the second heat sink along the first direction is 3mm~3.3mm; the spacing size between adjacent bar strips along the first direction is 0.05mm~0.5mm; the spacing size between adjacent second heat sinks along the first direction is 0.05mm~0.5mm.

[0017] Optionally, there are a plurality of intervals between one of the bars and one of the first heat sinks.

[0018] The present application also provides a packaging method for a semiconductor packaging structure, comprising: arranging a second heat sink on one side of a partial area of ​​a first heat sink, the second heat sink comprising: an insulating heat-conducting layer, a first conductive layer and a second conductive layer, the first conductive layer being located on one side surface of the insulating heat-conducting layer in a thickness direction, and the second conductive layer being located on the other side surface of the insulating heat-conducting layer in a thickness direction; welding a bar to a side surface of the second heat sink away from the first heat sink through a first welding layer, the material of the first welding layer being a hard solder; wherein the thermal conductivity of the insulating heat-conducting layer is greater than the thermal conductivity of the bar, and the thermal expansion coefficient of the insulating heat-conducting layer is less than the thermal expansion coefficient of the bar; arranging a first insulating layer on one side of a partial area of ​​the first heat sink and on a side of the second heat sink; arranging a first electrode sheet on a side of the first insulating layer away from the first heat sink, the first electrode sheet being electrically connected to a side surface of the first heat sink facing the bar; arranging a second insulating layer on a side of the first electrode sheet away from the first insulating layer; arranging a second electrode sheet on a side of the second insulating layer away from the first electrode sheet, the second electrode sheet also extending to a side surface of the bar away from the second heat sink.

[0019] Optionally, the method further includes: arranging a third heat sink on a side of the second electrode sheet away from the second insulating layer, wherein the third heat sink is electrically connected to the second electrode sheet.

[0020] Optionally, the method further includes: contacting a surface of the first heat sink on one side facing away from the bar with a cooling structure, and the cooling structure is grounded.

[0021] The technical solution of this application has the following beneficial effects:

[0022] In the semiconductor packaging structure provided by the technical solution of the present application, since the second heat sink includes an insulating heat-conducting layer, the second heat sink can electrically isolate the first heat sink from the bar. The first heat sink does not need to provide a voltage signal to the bar. Secondly, since the thermal conductivity of the insulating heat-conducting layer is greater than the thermal conductivity of the bar, the second heat sink can effectively conduct the heat in the bar to the first heat sink, and the second heat sink provides a good heat dissipation channel. Thirdly, since the thermal expansion coefficient of the insulating heat-conducting layer is less than the thermal expansion coefficient of the bar, the composite thermal expansion coefficient of the second heat sink can be close to the thermal expansion coefficient of the bar, thereby effectively reducing the packaging stress between the second heat sink and the bar. Since the packaging stress between the second heat sink and the bar is effectively reduced, it is not necessary to rely on the deformation of the first welding layer to release the stress, so the material of the first welding layer can be selected from hard solder, and then the material of the first welding layer is not easy to migrate to the bar, and the long-term reliability is high. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 A schematic diagram of a semiconductor packaging structure of the related art;

[0025] Figure 2 A schematic diagram of a semiconductor package structure according to an embodiment of the present application;

[0026] Figure 3 This is a simulation diagram of the stress variation of the bar in the slow axis direction in Test Example 1;

[0027] Figure 4 This is a simulation diagram of the stress change of the bar in the slow axis direction of Test Example 2. DETAILED DESCRIPTION

[0028] Figure 1 Schematic diagram of a semiconductor packaging structure of related technology, the semiconductor packaging structure includes: a first heat sink 10, the first heat sink 10 is a copper heat sink; a bar 15, located on a portion of the first heat sink 10, the positive electrode of the bar 15 faces the first heat sink 10; a first welding layer 14, located between the bar 15 and the first heat sink 10 and in contact with the bar 15 and the first heat sink 10; an insulating sheet 11, located on a portion of the first heat sink 10 and on the side of the bar 15; a negative electrode plate 12, located on a side of the insulating sheet 11 away from the first heat sink 10, the negative electrode of the bar 15 is connected to the negative electrode plate 12 through a wire; a second heat sink 13, located on a side of the negative electrode plate 12 away from the insulating sheet 11, the second heat sink 13 is electrically connected to the negative electrode plate 12.

[0029] However, the reliability of the above semiconductor packaging structure is poor. Research has found that the reasons are:

[0030] The first heat sink 10 is electrically connected to the positive pole of the bar 15, that is, the first heat sink 10 has polarity. Since the cooling structure used to cool the first heat sink 10 is grounded, the first heat sink 10 cannot be directly mounted on the cooling structure. Therefore, an insulating structure is provided between the first heat sink 10 and the cooling structure to insulate the first heat sink 10 from the ground signal. Since there is an insulating structure between the first heat sink 10 and the cooling structure, on the one hand, the structure is cumbersome and difficult to use, and on the other hand, the insulating structure has poor thermal conductivity of its own material, and the newly added contact thermal resistance after the insulating structure is provided increases, resulting in an increase in the working junction temperature of the semiconductor packaging structure.

[0031] If the material of the first welding layer 14 is a soft solder, such as indium, the deformation of the first welding layer 14 during the welding solidification process can release a part of the packaging stress caused by the mismatch of the thermal expansion coefficients between the first heat sink 10 and the bar 15. However, due to the large difference in the thermal expansion coefficients between the first heat sink 10 and the bar 15, even if the deformation of the first welding layer 14 during the welding solidification process releases a part of the packaging stress caused by the mismatch of the thermal expansion coefficients between the first heat sink 10 and the bar 15, the remaining packaging stress between the first heat sink 10 and the bar 15 is still large.

[0032] Since the material of the first welding layer 14 is soft solder, the material of the first welding layer 14 is easily migrated to the bar 15 , resulting in poor long-term reliability.

[0033] On this basis, the present application provides a semiconductor packaging structure and a packaging method of the semiconductor packaging structure, which improves the reliability of the semiconductor packaging structure.

[0034] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] An embodiment of the present invention provides a semiconductor packaging structure, referring to Figure 2 ,

[0038] A first heat sink 100;

[0039] A bar 160, located on one side of a partial area of ​​the first heat sink 100;

[0040] A second heat sink 180 is located between the first heat sink 100 and the bar 160. The second heat sink 180 includes: an insulating heat-conducting layer 181, wherein the thermal conductivity of the insulating heat-conducting layer 181 is greater than the thermal conductivity of the bar 160, and the thermal expansion coefficient of the insulating heat-conducting layer 181 is less than the thermal expansion coefficient of the bar 160; a first conductive layer 182 and a second conductive layer 183, wherein the first conductive layer 182 is located on one side of the insulating heat-conducting layer 181 in the thickness direction, and the second conductive layer 183 is located on the other side of the insulating heat-conducting layer 181 in the thickness direction;

[0041] A first welding layer 170, located between the bar 160 and the second heat sink 180 and in contact with the bar 160 and the second heat sink 180, wherein the material of the first welding layer 170 is hard solder;

[0042] A first insulating layer 110, located on one side of a partial area of ​​the first heat sink 100 and on a side of the second heat sink 180;

[0043] A first electrode sheet 120 , located on a side of the first insulating layer 110 away from the first heat sink 100 and electrically connected to a surface of a side of the first heat sink 100 facing the bar 160 ;

[0044] A second insulating layer 130 , located on a side of the first electrode sheet 120 away from the first insulating layer 110 ;

[0045] The second electrode sheet 140 is located on a side of the second insulating layer 130 away from the first electrode sheet 120 and extends to a surface of a side of the bar 160 away from the second heat sink 180 .

[0046] In this embodiment, since the second heat sink 180 includes an insulating heat conductive layer 181, the second heat sink 180 can electrically isolate the first heat sink 100 from the bar 160. The first heat sink 100 does not need to provide a voltage signal to the bar 160. Secondly, since the thermal conductivity of the insulating heat conductive layer 181 is greater than the thermal conductivity of the bar 160, the second heat sink 180 can effectively conduct the heat in the bar 160 to the first heat sink 100, and the second heat sink 180 provides a good heat dissipation channel. Thirdly, since the thermal expansion coefficient of the insulating heat conductive layer 181 is less than the thermal expansion coefficient of the bar 160, the composite thermal expansion coefficient of the second heat sink 180 can be close to the thermal expansion coefficient of the bar 160, thereby effectively reducing the packaging stress between the second heat sink 180 and the bar 160. Since the packaging stress between the second heat sink 180 and the bar 160 is effectively reduced, there is no need to rely on the deformation of the first welding layer 170 to release the stress. Therefore, the material of the first welding layer 170 can be selected as hard solder, and the material of the first welding layer 170 is not easy to migrate to the bar, and the long-term reliability is higher.

[0047] In one embodiment, the insulating heat-conducting layer 181 is made of aluminum nitride, and the first conductive layer 182 and the second conductive layer 183 are made of copper. The second heat sink 180 is copper-clad aluminum nitride.

[0048] The first conductive layer 182 and the second conductive layer 183 are electrically isolated from each other.

[0049] It should be noted that, in other embodiments, the material of the insulating heat-conducting layer may also be selected from other materials with high thermal conductivity and low thermal expansion coefficient. This is not limited here. In other embodiments, the first conductive layer and the second conductive layer may also be selected from other metal materials with high thermal conductivity.

[0050] The thermal conductivity of the insulating thermal conductive layer 181 is greater than the thermal conductivity of the bar 160 . In one embodiment, the thermal conductivity of the insulating thermal conductive layer 181 is more than twice the thermal conductivity of the bar 160 . Exemplarily, the thermal conductivity of the insulating thermal conductive layer 181 is 2, 4 or 6 times the thermal conductivity of the bar 160 .

[0051] The thermal expansion coefficient of the insulating heat-conducting layer 181 is smaller than the thermal expansion coefficient of the bar 160. In one embodiment, the thermal expansion coefficient of the insulating heat-conducting layer 181 is smaller than the thermal expansion coefficient of the bar 160 by 0.5×10 -6 / ℃~6×10 -6 / ℃.

[0052] In one embodiment, the difference between the composite thermal expansion coefficient of the second heat sink 180 and the composite thermal expansion coefficient of the bar 160 is less than or equal to 1×10 -6 / ℃.

[0053] In one embodiment, the thickness of the insulating heat-conducting layer 181 is 100μm~400μm, for example, 100μm, 200μm, 300μm or 400μm; the thickness of the first conductive layer 182 is 25μm~100μm, for example, 100μm, 200μm, 300μm or 400μm; the thickness of the second conductive layer 183 is 25μm~100μm.

[0054] In one embodiment, the thickness of the second heat sink 180 is less than or equal to 0.5 mm, such as 0.5 mm, 0.4 mm, 0.3 mm or 0.2 mm. The thickness of the second heat sink 180 is relatively small, so the influence on the working junction temperature is very small.

[0055] In one embodiment, the material of the first soldering layer 170 includes gold-tin solder.

[0056] The first welding layer 170 contacts the second conductive layer 183 and the bar 160 respectively.

[0057] In one embodiment, the thickness of the first welding layer 170 is 5 μm to 20 μm, for example, 5 μm, 8 μm, 10 μm, 12 μm, 15 μm or 20 μm. The thickness of the first welding layer 170 is less than or equal to 20 μm, so that the first welding layer 170 is not easily squeezed out to the light-emitting cavity surface of the bar during the packaging process, and the impact on the packaging stress and thermal resistance of the first welding layer 170 is very small; the thickness of the first welding layer 170 is greater than or equal to 5 μm, so that there is no welding void between the bar 160 and the second conductive layer 183.

[0058] In one embodiment, the semiconductor package structure further includes a second welding layer 190 , and the second welding layer 190 is located between the first heat sink 100 and the second heat sink 180 . The material of the second welding layer 190 includes soft solder.

[0059] In one embodiment, the material of the second welding layer 190 includes soft solder, so the deformation of the second welding layer 190 during the welding solidification process is used to release the packaging stress between the first heat sink 100 and the second heat sink 180. Even if the soft solder of the second welding layer 190 migrates and diffuses, since the second heat sink 180 isolates the second welding layer 190 and the bar 160, the material of the second welding layer 190 will not diffuse to the bar, and the reliability of the bar 160 is improved.

[0060] In one embodiment, the material of the second welding layer 190 includes indium solder.

[0061] In one embodiment, the thickness of the second welding layer 190 is greater than the thickness of the first welding layer 170. Since the thickness of the second welding layer 190 is greater, the allowable deformation of the second welding layer 190 during the welding solidification process is greater, which can release more packaging stress between the first heat sink 100 and the second heat sink 180. In one embodiment, the thickness of the second welding layer 190 is 2.5 to 10 times the thickness of the first welding layer 170.

[0062] In one embodiment, the thickness of the second welding layer 190 is 10 micrometers to 50 micrometers, 10 micrometers, 20 micrometers, 30 micrometers, 40 micrometers or 50 micrometers.

[0063] In this embodiment, the bar 160 includes: a semiconductor substrate; a first confinement layer, a first waveguide layer, an active layer, a second waveguide layer, and a second confinement layer stacked in sequence and located on one side of the semiconductor substrate; a front electrode located on the side of the second confinement layer away from the active layer; and a back electrode located on the side of the semiconductor substrate away from the active layer.

[0064] In one embodiment, the front electrode is located between the back electrode and the first heat sink 100; wherein the first electrode sheet is a positive electrode sheet, and the second electrode sheet is a negative electrode sheet. Since the heat on the front side of the bar 160 is greater than the heat on the back side of the bar, the front electrode is located between the back electrode and the first heat sink 100, so that the heat on the front side of the bar 160 can be transferred to the first heat sink 100 through the second heat sink in time, thereby improving the heat dissipation capacity.

[0065] In another embodiment, the back electrode is located between the front electrode and the first heat sink; wherein the first electrode sheet 120 is a negative electrode sheet, and the second electrode sheet 140 is a positive electrode sheet.

[0066] The back electrode and the front electrode of the bar 160 are both electrically isolated from the first heat sink 100 .

[0067] In this embodiment, the first heat sink 100 includes a copper heat sink.

[0068] In this embodiment, the thermal expansion coefficient of the first heat sink 100 is greater than the thermal expansion coefficient of the bar 160. Specifically, the thermal expansion coefficient of the first heat sink 100 is 17×10 -6 / ℃~20×10 -6 / ℃, the thermal expansion coefficient of bar 160 is 4.5×10 -6 / ℃~7×10 -6 / ℃.

[0069] In this embodiment, the semiconductor package structure further includes: a third heat sink 150 , which is located on a side of the second electrode sheet 140 away from the second insulating layer 130 and is electrically connected to the second electrode sheet 140 .

[0070] In this embodiment, the third heat sink 150 includes a copper heat sink.

[0071] In this embodiment, it further comprises: a fastener for fastening the third heat sink 150, the second electrode sheet 140, the second insulating layer 130, the first electrode sheet 120, the first insulating layer 110 and the first heat sink 100. The fastener comprises an insulating screw.

[0072] In one embodiment, the first heat sink 100 is non-polar.

[0073] In another embodiment, the semiconductor package structure further comprises: a cooling structure, the cooling structure is grounded; wherein a surface of the first heat sink facing away from the bar contacts the cooling structure. In one embodiment, the cooling structure is a metal shell, the metal shell surrounds the first heat sink, the bar, the second heat sink, the first welding layer, the first insulating layer, the first electrode sheet, the second insulating layer, the second electrode sheet, the second welding layer and the third heat sink.

[0074] The first heat sink 100 can contact a cooling structure for cooling the first heat sink 100 and grounding the first heat sink 100 , and there is no need to provide an insulating structure between the first heat sink 100 and the cooling structure, so that the structure is simplified and the working junction temperature of the semiconductor package structure is reduced.

[0075] In one embodiment, the number of the bar strips 160, the second heat sink 180, and the first welding layer 170 are all multiple; the multiple bar strips 160 are arranged at intervals along a first direction parallel to the surface of the first heat sink 100, and the multiple second heat sinks 180 are arranged at intervals along the first direction. The first direction is the slow axis direction of the bar strips.

[0076] In one embodiment, the size of the bar 160 along the first direction is 3mm-3.3mm, and the size of the second heat sink 180 along the first direction is 3mm-3.3mm; the spacing size between adjacent bar 160 along the first direction is 0.05mm~0.5mm; the spacing size between adjacent second heat sinks 180 along the first direction is 0.05mm~0.5mm.

[0077] Since the dimensions of the bar 160 and the second heat sink 180 in the first direction are both relatively small, the packaging stress on each bar is relatively small.

[0078] In one embodiment, a plurality of intervals of the second heat sinks 180 are provided between one of the bar strips 160 and one of the first heat sinks 100 .

[0079] In one embodiment, since the spacing distance between adjacent bars 160 is relatively close, when a plurality of the bars 160 are spaced apart along a first direction parallel to the surface of the first heat sink 100, the light intensity at the center of the adjacent bars 160 at a distance of 5 cm in the light emitting direction is more than 90% of the light intensity at the center of the front cavity surface of the bars 160 at a distance of 5 cm in the light emitting direction.

[0080] Test Example 1: The semiconductor package structure includes a first heat sink, a bar, a second heat sink, a first welding layer, a first insulating layer, a first electrode sheet, a second insulating layer, a second electrode sheet, a second welding layer and a third heat sink. The bar has a size of 9.8 mm to 12 mm in the first direction.

[0081] Test Example 2: The semiconductor packaging structure includes a first heat sink, a bar, a second heat sink, a first welding layer, a first insulating layer, a first electrode sheet, a second insulating layer, a second electrode sheet, a second welding layer and a third heat sink. The number of the bar and the second heat sink are both multiple. The multiple bar is arranged at intervals along a first direction parallel to the surface of the first heat sink, and the multiple second heat sinks are arranged at intervals along the first direction. The size of the bar along the first direction is 3.3 mm, the size of the second heat sink along the first direction is 3.3 mm, the spacing size between adjacent second heat sinks along the first direction is 0.05 mm, and the spacing size between adjacent bar along the first direction is 0.05 mm.

[0082] Figure 3 This is a simulation diagram of the stress variation of the bar in the slow axis direction in Test Example 1. Figure 4 This is a simulation diagram of the stress change of the bar in the slow axis direction of test example 2. Figure 3 and Figure 4 The stress in the central main area of ​​the bar increases from 2.4×10 8 N / m 2 Reduced to 1.8×10 8 N / m 2 .

[0083] Another embodiment of the present application also provides a packaging method for a semiconductor packaging structure, comprising: arranging a second heat sink on one side of a partial area of ​​a first heat sink, the second heat sink comprising: an insulating heat-conducting layer, a first conductive layer, and a second conductive layer, the first conductive layer being located on one side surface of the insulating heat-conducting layer in a thickness direction, and the second conductive layer being located on the other side surface of the insulating heat-conducting layer in a thickness direction; welding a bar to a side surface of the second heat sink away from the first heat sink through a first welding layer, the material of the first welding layer being a hard solder; wherein the thermal conductivity of the insulating heat-conducting layer is greater than the thermal conductivity of the bar, and the thermal expansion coefficient of the insulating heat-conducting layer is less than the thermal expansion coefficient of the bar; arranging a first insulating layer on one side of a partial area of ​​the first heat sink and on a side of the second heat sink; arranging a first electrode sheet on a side of the first insulating layer away from the first heat sink, the first electrode sheet being electrically connected to a side surface of the first heat sink facing the bar; arranging a second insulating layer on a side of the first electrode sheet away from the first insulating layer; arranging a second electrode sheet on a side of the second insulating layer away from the first electrode sheet, the second electrode sheet also extending to a side surface of the bar away from the second heat sink.

[0084] The packaging method further includes: arranging a third heat sink on a side of the second electrode sheet away from the second insulating layer, wherein the third heat sink is electrically connected to the second electrode sheet.

[0085] Disposing the second heat sink on one side of the partial region of the first heat sink includes: welding the second heat sink and the first heat sink using a second welding layer.

[0086] The packaging method further includes: bringing a surface of the first heat sink facing away from the bar into contact with the cooling structure, and the cooling structure is grounded.

[0087] The description of the first heat sink, the second heat sink, the bar, the first welding layer, the first insulating layer, the first electrode sheet, the second insulating layer, the second electrode sheet, the third welding layer and the third heat sink refers to the description of the previous embodiment.

[0088] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A semiconductor packaging structure, characterized in that: include: First heat sink; A bar located on one side of a partial area of ​​the first heat sink; a second heat sink, located between the first heat sink and the bar, the second heat sink comprising: an insulating heat-conducting layer, the thermal conductivity of the insulating heat-conducting layer being greater than the thermal conductivity of the bar, and the thermal expansion coefficient of the insulating heat-conducting layer being less than the thermal expansion coefficient of the bar; a first conductive layer and a second conductive layer, the first conductive layer being located on one side surface of the insulating heat-conducting layer in the thickness direction, and the second conductive layer being located on the other side surface of the insulating heat-conducting layer in the thickness direction; A first welding layer, located between the bar and the second heat sink and in contact with the bar and the second heat sink, wherein the material of the first welding layer is hard solder; A first insulating layer, located on one side of a partial area of ​​the first heat sink and on a side portion of the second heat sink; A first electrode sheet, located on a side of the first insulating layer away from the first heat sink and electrically connected to a surface of a side of the first heat sink facing the bar; a second insulating layer, located on a side of the first electrode sheet away from the first insulating layer; The second electrode sheet is located on a side of the second insulating layer away from the first electrode sheet and extends to a surface of a side of the bar away from the second heat sink.

2. The semiconductor package structure according to claim 1, characterized in that The material of the insulating thermal conductive layer includes aluminum nitride, and the materials of the first conductive layer and the second conductive layer include copper.

3. The semiconductor package structure according to claim 1, characterized in that The thickness of the insulating heat-conducting layer is 100 μm-400 μm; the thickness of the first conductive layer is 25 μm-100 μm; the thickness of the second conductive layer is 25 μm-100 μm.

4. The semiconductor package structure according to claim 1, characterized in that , the material of the first welding layer includes gold-tin solder.

5. The semiconductor package structure according to claim 1, characterized in that , the thickness of the first welding layer is 5μm-20μm.

6. The semiconductor package structure according to claim 1, characterized in that The bar includes: a semiconductor substrate; a first confinement layer, a first waveguide layer, an active layer, a second waveguide layer, and a second confinement layer stacked in sequence on one side of the semiconductor substrate; a front electrode located on a side of the second confinement layer away from the active layer; and a back electrode located on a side of the semiconductor substrate away from the active layer. Wherein, the front electrode is located between the back electrode and the first heat sink; Wherein, the first electrode sheet is a positive electrode sheet, and the second electrode sheet is a negative electrode sheet.

7. The semiconductor package structure according to claim 1, characterized in that , also includes: a second welding layer, located between the first heat sink and the second heat sink, the material of the second welding layer includes soft solder.

8. The semiconductor package structure according to claim 7, characterized in that , the thickness of the second welding layer is greater than the thickness of the first welding layer.

9. The semiconductor package structure according to claim 7, characterized in that ,The thickness of the second welding layer is 10 microns to 50 microns.

10. The semiconductor package structure according to claim 1, characterized in that , also includes: a third heat sink, located on a side of the second electrode sheet away from the second insulating layer and electrically connected to the second electrode sheet.

11. The semiconductor package structure according to claim 1, characterized in that , also includes: a cooling structure, the cooling structure is grounded; wherein, the side surface of the first heat sink facing away from the bar is in contact with the cooling structure.

12. The semiconductor package structure according to claim 1, characterized in that , the number of the bar strips, the second heat sink, and the first welding layer are all multiple; the multiple bar strips are arranged at intervals along a first direction parallel to the surface of the first heat sink, and the multiple second heat sinks are arranged at intervals along the first direction; Among them, the size of the bar along the first direction is 3mm~3.3mm, and the size of the second heat sink along the first direction is 3mm~3.3mm; the spacing size between adjacent bar strips along the first direction is 0.05mm~0.5mm; the spacing size between adjacent second heat sinks along the first direction is 0.05mm~0.5mm.

13. The semiconductor package structure according to claim 1, characterized in that , a second heat sink having multiple intervals between one of the bar strips and one of the first heat sinks.

14. A packaging method for a semiconductor packaging structure, characterized in that: include: The second heat sink is arranged on one side of a partial area of ​​the first heat sink, wherein the second heat sink comprises: an insulating heat-conducting layer, a first conductive layer and a second conductive layer, wherein the first conductive layer is located on one side surface of the insulating heat-conducting layer in a thickness direction, and the second conductive layer is located on the other side surface of the insulating heat-conducting layer in a thickness direction; The bar is welded together with a surface of a second heat sink facing away from the first heat sink through a first welding layer, wherein the material of the first welding layer is a hard solder; wherein the thermal conductivity of the insulating heat-conducting layer is greater than the thermal conductivity of the bar, and the thermal expansion coefficient of the insulating heat-conducting layer is less than the thermal expansion coefficient of the bar; Disposing a first insulating layer on one side of a partial area of ​​the first heat sink and on a side portion of the second heat sink; A first electrode sheet is disposed on a side of the first insulating layer facing away from the first heat sink, and the first electrode sheet is electrically connected to a surface of a side of the first heat sink facing the bar; Disposing a second insulating layer on a side of the first electrode sheet away from the first insulating layer; A second electrode sheet is disposed on a side of the second insulating layer away from the first electrode sheet, and the second electrode sheet further extends to a surface of a side of the bar away from the second heat sink.

15. The packaging method according to claim 14, characterized in that: Also includes: A third heat sink is disposed on a side of the second electrode sheet away from the second insulating layer, and the third heat sink is electrically connected to the second electrode sheet.

16. The packaging method according to claim 14, characterized in that: Also includes: A surface of the first heat sink facing away from the bar is brought into contact with a cooling structure, and the cooling structure is grounded.

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