Packaging structure, pump source and laser

Abstract

The utility model relates to the technical field of laser, disclose a packaging structure, pump source and laser. Wherein the packaging structure includes the packaging unit, and the packaging unit includes insulating substrate, first composite heat dissipation part, wire and chip, and first composite heat dissipation part sets up in the top of insulating substrate, chip is connected with first composite heat dissipation part, and one end of wire is electrically connected with chip, and the packaging unit is provided with the electrode layer of insulating setting with first composite heat dissipation part, and the other end of wire is connected with electrode layer, or the packaging unit still is provided with second composite heat dissipation part of insulating setting with first composite heat dissipation part, and second composite heat dissipation part sets up in the top of insulating substrate, and the other end of wire is connected with second composite heat dissipation part. The utility model discloses a packaging structure, guarantees the insulating of packaging structure simultaneously, improves its heat dissipation capacity, and also has the advantage that the cost is low.

Description

Technical Field

[0001] This utility model relates to the field of laser technology, and in particular to a packaging structure, a pump source, and a laser. Background Technology

[0002] In existing packaging structures, aluminum nitride copper-clad laminates are used as transitional heat sinks. On one hand, aluminum nitride's coefficient of thermal expansion is close to that of the chip, and its thermal conductivity is typically 170 W / mK-250 W / mK, providing initial thermal diffusion that matches the chip's coefficient of thermal expansion. On the other hand, the copper-clad laminate not only provides superior thermal diffusion capabilities compared to aluminum nitride, but also acts as a conductive material, injecting electrical energy into chips that require power, such as laser diodes.

[0003] However, with the increasing power of chips and the growing trend towards miniaturization in devices requiring these chips, such as fiber lasers, there is a need to improve chip heat dissipation capabilities to reduce system heat dissipation volume. The thermal conductivity of aluminum nitride is limited by the theoretical upper limit of its thermal conductivity, resulting in limited improvement and thus limited impact on improving the thermal resistance of chip packaging.

[0004] Although copper / diamond has excellent thermal conductivity, typically between 600W / mK and 900W / mK, and is inexpensive, it cannot directly replace existing aluminum nitride copper-clad laminates due to the material's inherent electrical conductivity, thus hindering its mass production in the market.

[0005] Therefore, there is an urgent need for a packaging structure, pump source, and laser to solve the above problems. Utility Model Content

[0006] Based on the above, the purpose of this utility model is to provide a packaging structure, a pump source, and a laser that improves the heat dissipation capacity while ensuring the insulation of the packaging structure, and also has the advantage of low cost.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] The packaging structure includes a packaging unit, wherein the packaging unit includes:

[0009] Insulating substrate;

[0010] The first composite heat dissipation part is disposed above the insulating substrate;

[0011] A chip and a bonding wire, wherein the chip is connected to a first composite heat sink that is conductive and dissipates heat, and one end of the bonding wire is electrically connected to the chip;

[0012] The packaging unit further includes an electrode layer that is insulated from the first composite heat dissipation part, and the other end of the bonding wire is connected to the electrode layer;

[0013] or,

[0014] The packaging unit further includes a second composite heat dissipation part that is electrically conductive and heat dissipating, which is insulated from the first composite heat dissipation part. The second composite heat dissipation part is disposed above the insulating substrate, and the other end of the bonding wire is connected to the second composite heat dissipation part.

[0015] As a preferred embodiment of the packaging structure, the first composite heat dissipation part is a first diamond copper heat dissipation part; the second composite heat dissipation part is a second diamond copper heat dissipation part.

[0016] As a preferred embodiment of the packaging structure, the first diamond copper heat dissipation part is sintered and connected to the insulating substrate; a third composite heat dissipation part that is conductive and dissipates heat is provided below the insulating substrate, and the third composite heat dissipation part is sintered and connected to the insulating substrate.

[0017] As a preferred embodiment of the packaging structure, the first diamond copper heat sink is brazed to the insulating substrate.

[0018] As a preferred embodiment of the packaging structure, the thickness of the first diamond copper heat sink is set to 0.1mm-1mm; and / or, the thickness of the insulating substrate is set to 0.05mm-1mm.

[0019] As a preferred embodiment of the packaging structure, the packaging unit is further provided with a first lead and a second lead. The first lead is connected to the chip through the first composite heat dissipation part, and the second lead is connected to the other end of the bonding wire through the electrode layer or the second composite heat dissipation part.

[0020] As a preferred embodiment of the packaging structure, a first soldering layer is provided on the first composite heat dissipation part, and the chip and the first lead are both connected to the first soldering layer.

[0021] As a preferred embodiment of the packaging structure, the packaging structure is provided with two or more packaging units, which are connected in series through the first lead and the second lead in sequence.

[0022] The pump source includes the packaging structure described in any of the above solutions.

[0023] The laser includes the pump source described in any of the above embodiments.

[0024] The beneficial effects of this utility model are as follows:

[0025] This invention improves heat dissipation by setting a first composite heat dissipation part on an insulating substrate and placing the chip on the first composite heat dissipation part. This ensures both insulation and matching of thermal expansion coefficients between the chip and the substrate, while also improving the chip's heat dissipation capacity. Furthermore, the first composite heat dissipation part has the advantage of low cost. Specifically, the chip also has bonding wires. The packaging unit can set an electrode layer on the insulating substrate and electrically connect the bonding wires to the electrode layer. Alternatively, the packaging unit can also set a second composite heat dissipation part on the insulating substrate and electrically connect the bonding wires to the second composite heat dissipation part. The second composite heat dissipation part not only achieves electrical connection with the bonding wires but also improves heat dissipation at the connection point, thereby further improving the heat dissipation effect of the packaging structure. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of this utility model and these drawings without creative effort.

[0027] Figure 1 This is a perspective view of a packaging structure provided by a specific embodiment of this utility model;

[0028] Figure 2 This is a side view of an encapsulation structure provided in a specific embodiment of this utility model;

[0029] Figure 3 This is a perspective view of another packaging structure provided by a specific embodiment of this utility model;

[0030] Figure 4 This is a side view of another packaging structure provided in a specific embodiment of this utility model.

[0031] In the picture:

[0032] 100. Insulating substrate;

[0033] 200, First composite heat dissipation unit; 210, First solder flux layer;

[0034] 310. Chip; 320. First lead; 330. Bonding wire; 340. Second lead;

[0035] 410. Electrode layer; 420. Second composite heat dissipation unit; 421. Second flux layer; 430. Third composite heat dissipation unit; 431. Third flux layer. Detailed Implementation

[0036] The embodiments of this utility model are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0037] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions.

[0038] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and connections within two components or interactions between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0039] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0040] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0041] like Figures 1-4As shown, this embodiment provides a packaging structure, which includes a packaging unit. The packaging unit includes an insulating substrate 100, a first composite heat dissipation part 200, a bonding wire 330, and a chip 310. The first composite heat dissipation part 200 is disposed above the insulating substrate 100. The chip 310 is connected to the conductive and heat-dissipating first composite heat dissipation part 200. One end of the bonding wire 330 is electrically connected to the chip 310. The packaging unit also includes an electrode layer 410 that is insulated from the first composite heat dissipation part 200, and the bonding wire 330 is connected to the electrode layer 410. Alternatively, the packaging unit also includes a second composite heat dissipation part 420 that is insulated from the first composite heat dissipation part 200 and is conductive and heat-dissipating. The second composite heat dissipation part 420 is disposed above the insulating substrate 100, and the bonding wire 330 is connected to the second composite heat dissipation part 420.

[0042] The first composite heat dissipation part 200 is a first diamond-copper heat dissipation part. By setting the first diamond-copper heat dissipation part on the insulating substrate 100 and placing the chip 310 on the first diamond-copper heat dissipation part, the heat dissipation capacity of the chip 310 is improved while ensuring the insulation and thermal expansion coefficient matching between the chip 310 and the first diamond-copper heat dissipation part 200. In addition, the first diamond-copper heat dissipation part also has the advantage of low cost. Specifically, the chip 310 is also provided with bonding wires 330. The packaging unit can set an electrode layer 410 on the insulating substrate 100 that is insulated from the first composite heat dissipation part 200, and simultaneously make the bonding wires 330 electrically connected to the electrode layer 410; or, the packaging unit can also set a second composite heat dissipation part 420 on the insulating substrate 100 that is insulated from the first composite heat dissipation part 200, and simultaneously make the bonding wires 330 electrically connected to the second composite heat dissipation part 420. The solution of the second composite heat dissipation part 420 not only realizes the electrical connection of the bonding wires 330, but also helps to improve the heat dissipation at the connection position, thereby further improving the heat dissipation effect of the packaging structure. The second composite heat dissipation unit 420 is a second diamond copper heat dissipation unit.

[0043] Understandably, to prevent chip 310 from being short-circuited, such as Figure 3 and Figure 4 As shown, when the insulating substrate 100 is provided with an electrode layer 410, the electrode layer 410 and the first composite heat dissipation portion 200 are disposed at a distance; as Figure 1 and Figure 2 As shown, when the package structure is provided with a second composite heat dissipation part 420, the second composite heat dissipation part 420 is spaced apart from the first composite heat dissipation part 200. For example, the spacing direction between the electrode layer 410 or the second composite heat dissipation part 420 and the first composite heat dissipation part 200 is perpendicular to the extension direction of the chip 310, and the spacing distance is consistent at all points along the extension direction of the chip 310. This spacing distance should not be too small to ensure insulation, nor should it be too large to ensure the miniaturization of the package structure.

[0044] In one embodiment, the first composite heat dissipation part 200 is sintered and connected to the insulating substrate 100.

[0045] Preferably, such as Figure 1 and Figure 2 As shown, a third composite heat dissipation part 430 is provided below the insulating substrate 100, and the third composite heat dissipation part 430 is sintered and formed to the insulating substrate 100. The third composite heat dissipation part 430 is a third diamond copper heat dissipation part. By providing the third composite heat dissipation part 430, the heat dissipation performance of the packaging structure is improved, and the symmetry of the packaging structure is also increased, thereby improving the stress on the packaging structure during the sintering process and effectively preventing warping during the sintering process.

[0046] It is worth noting that in the embodiment using sintering molding, when the insulating substrate 100 is provided with an electrode layer 410, the width of the third composite heat dissipation part 430 is adapted to the width of the first composite heat dissipation part 200; when the encapsulation structure is provided with a second composite heat dissipation part 420, the width of the third composite heat dissipation part 430 is adapted to the width of the first composite heat dissipation part 200 and the second composite heat dissipation part 420, so as to ensure that the force on both sides of the insulating substrate is balanced.

[0047] Specifically, the packaging unit also includes a first lead 320 and a second lead 340. The first lead 320 is connected to the chip 310 via a first composite heat sink 200, and the second lead 340 is connected to the other end of a bonding wire 330 via an electrode layer 410 or the second composite heat sink 420. Since the bonding wire 330 is electrically connected to the chip 310, the second lead 340 is also connected to the chip 310. By providing the first lead 320 and the second lead 340, both electrically connected to the chip 310, series and parallel connections between multiple packaging units are made, as well as connections between the packaging units and external circuits, to achieve the preset functions of the chip 310. The first lead 320 is located in the first composite heat sink 200, which not only enables its electrical connection to the chip 310 but also improves heat dissipation at the connection point.

[0048] Furthermore, to ensure reliability when the chip 310 and the first lead 320 are electrically connected through the first composite heat sink 200, a first soldering layer 210 is provided on the first composite heat sink 200, and both the chip 310 and the first lead 320 are connected to the first soldering layer 210. Providing the first soldering layer 210 improves the solderability and bonding capability of the first composite heat sink 200. For example, the bonding wire 330 is a gold wire and is bonded to the chip 310. Specifically, the first soldering layer 210 improves the reliability of the soldering of the chip 310 to the first composite heat sink 200 using gold-tin solder, and the reliability of the connection between the first lead 320 and the first composite heat sink 200 via bonding. When the package structure includes a second composite heat sink 420, a second soldering layer 421 is provided on the second composite heat sink 420, and both the second lead 340 and the bonding wire 330 are bonded to the second composite heat sink 420. The provision of the second soldering layer 421 further improves the reliability of the aforementioned connections.

[0049] Optionally, the first flux layer 210 and / or the second flux layer 421 can be thin films formed by deposition, electroplating of Ni / Au, Ni / Pd / Au, or Ti / Pt / Au, etc. It is worth noting that the third composite heat dissipation part 430 can also be provided with a third flux layer 431. The purpose and method of providing the third flux layer 431 are the same as those of the first flux layer 210 and / or the second flux layer 421, and are not specifically limited here.

[0050] For example, the insulating substrate 100 may be made of materials such as silicon nitride, beryllium oxide, aluminum nitride, silicon carbide, or diamond. The chip 310 may be a laser diode chip 310. Further, the thickness of the first composite heat dissipation part 200 is set to 0.1mm-1mm to ensure effective heat dissipation; the thickness of the insulating substrate 100 is set to 0.05mm-1mm to ensure reliable insulation.

[0051] In this embodiment, the packaging structure has two or more packaging units, which are connected in series through the first lead 320 and the second lead 340. Since different laser diodes have significantly different current-voltage characteristic curves, if they are used in parallel, the consistency of the current flowing through them will be poor, and the reliability will be greatly reduced. Therefore, laser diodes are often used in series. However, series-connected packaging units mean that the electrodes of the laser diodes in different packaging units will be at different potentials. In this case, the insulating substrate 100 and the bottom of the first composite heat sink 200 can effectively provide electrical isolation. It is worth noting that the size and thickness of the first composite heat sink 200, as well as the connection method between the first composite heat sink 200 and the insulating substrate 100, and the connection method between the second lead 340 and the bonding wire 330, can all be set according to the different needs of different packaging units to adapt to the heat dissipation effects required by different packaging units.

[0052] This embodiment also discloses a pump source, including the packaging structure described in any of the above embodiments. The pump source with the above-described packaging structure has better insulation and heat dissipation capabilities for the electronic components, and also has the advantage of low cost.

[0053] This embodiment also discloses a laser, including the pump source described in any of the above schemes, which has better performance, lower cost, and better market competitiveness.

[0054] In another embodiment, such as Figure 3 and Figure 4 As shown, the first composite heat dissipation part 200 is soldered to the insulating substrate 100. Solder soldering refers to the process of heating a solder (such as tin-lead solder, lead-free solder, or gold-tin solder) with a melting point lower than that of the base material (chip 310 / substrate metal layer) to melt it. The liquid solder wets the surface of the base material and fills the gaps. After cooling, it solidifies to form a bonding layer, while the base material remains solid throughout.

[0055] Specifically, the electrode layer 410 is a thin copper layer sputtered on the surface of the insulating layer, or the electrode layer 410 can also be a copper layer thickened by electroplating on the insulating substrate 100. Meanwhile, the insulating substrate 100 can also be connected to the pump source housing by soldering.

[0056] For example, the solder can be tin-silver-copper solder, or other solders such as silver-copper-titanium, or solders with multiple melting points; no specific limitation is made here.

[0057] In summary, it is worth noting that, as shown in the table below, in the technical solution where a first composite heat dissipation part 200 and a second composite heat dissipation part 420 are provided and formed by sintering, the thermal conductivity of the first composite heat dissipation part 200, the material and thermal conductivity of the insulating substrate 100, etc., affect the overall heat dissipation effect of the packaging structure. Taking the sintering and connection of the first composite heat dissipation part 200 and the insulating substrate 100 as an example, under 42W light emission conditions: when the thermal conductivity of the first composite heat dissipation part 200 is 650W / mK and the thermal conductivity of the aluminum nitride insulating substrate 100 is 220W / mK, the junction temperature of the packaging structure can be reduced by 6.901℃; when the thermal conductivity of the first composite heat dissipation part 200 is 800W / mK and the thermal conductivity of the aluminum nitride insulating substrate 100 is 220W / mK, the junction temperature of the packaging structure can be reduced by 8.362℃; when the thermal conductivity of the first composite heat dissipation part 200 is 800W / mK and the thermal conductivity of the polycrystalline diamond insulating substrate 100 is 800W / mK, the junction temperature of the packaging structure can be reduced by 10.23℃. That is, the above packaging structure can effectively improve heat dissipation.

[0058]

[0059] The above description is only a preferred embodiment of this utility model. For those skilled in the art, there will be changes in the specific implementation method and application scope based on the idea of ​​this utility model. The content of this specification should not be construed as a limitation of this utility model.

Claims

1. A packaging structure, characterized in that, Includes a packaging unit, the packaging unit comprising: Insulating substrate (100); A first composite heat dissipation part (200) is disposed above the insulating substrate (100); A chip (310) and a bonding wire (330), wherein the chip (310) is connected to a first composite heat sink (200) that is conductive and heat-dissipating, and one end of the bonding wire (330) is electrically connected to the chip (310); The packaging unit further includes an electrode layer (410) that is insulated from the first composite heat dissipation part (200), and the other end of the bonding wire (330) is connected to the electrode layer (410); or, The packaging unit further includes a conductive and heat-dissipating second composite heat dissipation part (420) that is insulated from the first composite heat dissipation part (200). The second composite heat dissipation part (420) is disposed above the insulating substrate (100), and the other end of the bonding wire (330) is connected to the second composite heat dissipation part (420).

2. The packaging structure according to claim 1, characterized in that, The first composite heat dissipation part (200) is a first diamond copper heat dissipation part; the second composite heat dissipation part (420) is a second diamond copper heat dissipation part.

3. The packaging structure according to claim 2, characterized in that, The first diamond copper heat dissipation part is sintered and connected to the insulating substrate (100); a third composite heat dissipation part (430) that can conduct electricity and dissipate heat is provided below the insulating substrate (100), and the third composite heat dissipation part (430) is sintered and connected to the insulating substrate (100).

4. The packaging structure according to claim 2, characterized in that, The first diamond copper heat sink is brazed to the insulating substrate (100) with solder.

5. The packaging structure according to claim 2, characterized in that, The thickness of the first diamond copper heat sink is set to 0.1mm-1mm; and / or the thickness of the insulating substrate (100) is set to 0.05mm-1mm.

6. The packaging structure according to any one of claims 1-5, characterized in that, The packaging unit is further provided with a first lead (320) and a second lead (340). The first lead (320) is connected to the chip (310) through the first composite heat dissipation part (200), and the second lead (340) is connected to the other end of the bonding wire (330) through the electrode layer (410) or the second composite heat dissipation part (420).

7. The packaging structure according to claim 6, characterized in that, The first composite heat dissipation part (200) is provided with a first soldering layer (210), and the chip (310) and the first lead (320) are both connected to the first soldering layer (210).

8. The packaging structure according to claim 6, characterized in that, The packaging structure is provided with two or more packaging units, which are connected in series through the first lead (320) and the second lead (340) in sequence.

9. A pump source, characterized in that, Includes the packaging structure as described in any one of claims 1-8.

10. A laser, characterized in that, Includes the pump source as described in claim 9.

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