Electrical connection structure of semiconductor laser chip

Abstract

The utility model provides an electrical connection structure of a semiconductor laser chip, which is used for solving the technical problems that the increased heat dissipation area of the existing semiconductor packaging structure is limited, and the heat dissipation requirement of a chip with larger heat production is difficult to meet. The utility model comprises a metal bonding plate and a solder contact layer, wherein the metal bonding plate is in eutectic connection with an electrode on the upper surface of a laser chip through the solder contact layer. According to the utility model, the metal connecting wire part is directly replaced by the metal bonding plate, so that the heat dissipation surface of the chip can be increased to the greatest extent, and the heat of the chip can be effectively dissipated; through the metal bonding plate and the solder contact layer, the heat dissipation efficiency of the chip can be improved while electrical connection is provided, so that the laser can still keep stable and efficient performance under high-power operation. The semiconductor laser improves heat dissipation efficiency, reduces influence of heat effect on laser performance, omits a metal routing step, reduces production cost, improves production efficiency, and greatly improves overall performance of the semiconductor laser.

Description

Electrical connection structure of a semiconductor laser chip Technical Field

[0001] This utility model relates to the technical field of semiconductor lasers, and in particular to an electrical connection structure for a semiconductor laser chip. Background Technology

[0002] Semiconductor lasers have been widely used in various fields such as industrial processing, medical treatment, communications, and scientific research. As a core component, the performance of the laser directly affects the stability and reliability of the entire system. The stability and heat dissipation efficiency of the laser have become key factors restricting its development. To ensure that semiconductor lasers can operate stably for extended periods in various complex environments, in addition to the laser's design and materials, the electrical connection module and its heat dissipation design are also crucial factors. Traditional laser electrical connections typically use gold wire bonding, a cumbersome process, especially in high-density integration applications where limited space and difficult wire bonding can easily lead to poor contact, wire breakage, and other problems, thus affecting the laser's operational stability. Furthermore, traditional electrical connection modules lack heat dissipation capabilities. When operating at high power, semiconductor lasers are prone to excessive temperature rise due to poor heat dissipation, affecting their performance and lifespan.

[0003] To address these issues, various improvement solutions have emerged in the market. For example, using more efficient heat-dissipating materials and more compact structural designs to improve heat dissipation performance; or employing simpler electrical connection methods to reduce wiring operations. However, these solutions either have insufficient heat dissipation effects or still require additional complex operations to achieve electrical connections, and they cannot significantly reduce production costs. Therefore, there is an urgent need for a new type of module that can both improve heat dissipation efficiency and simplify the electrical connection process.

[0004] Patent application number 202410248841.8 discloses a semiconductor device packaging structure and its fabrication method, including an aluminum substrate. The aluminum substrate has a support and protection mechanism and a heat dissipation auxiliary mechanism. Solder balls are fixed to the bottom of the aluminum substrate, and two insulating layers are fixed to the top. The support and protection mechanism includes a plastic encapsulation shell, protective adhesive, and inserts. The plastic encapsulation shell is installed on the top of the aluminum substrate, and two protective adhesives are disposed inside the plastic encapsulation shell. The protective adhesives are fixed to the support strips, which are fixed to the top of the aluminum substrate. In the above invention, the second and first reinforcing strips support the protective adhesives on both sides. The protective adhesives and the second sealant reinforce the mounting of the metal bonding wires and the semiconductor chip, respectively, facilitating the connection between circuits. The solder pad area is large, reducing the possibility of the semiconductor chip being damaged during use. The auxiliary strips contact the semiconductor chip at both ends for heat dissipation. The die-bonding layer and the thermally conductive silicone layer work together to improve the overall heat dissipation effect and extend the lifespan of the circuit. Although the above invention adds auxiliary strips to increase the heat dissipation contact area, the increase in heat dissipation area is limited and still cannot meet the heat dissipation requirements of chips that generate a lot of heat. Especially for high-power laser chips, heat dissipation is still a key factor affecting their operational stability. Summary of the Invention

[0005] To address the technical problem that existing semiconductor lasers cannot meet heat dissipation requirements, this invention proposes an electrical connection structure for semiconductor laser chips. By directly replacing the metal connecting wires with metal bonding plates, the heat dissipation surface of the chip is maximized, effectively cooling the chip. Through the metal bonding plate and solder contact layer, this invention provides electrical connection while simultaneously improving chip heat dissipation efficiency, ensuring that the laser maintains stable and efficient performance even under high-power operation.

[0006] To achieve the above objectives, the technical solution of this utility model is as follows: an electrical connection structure for a semiconductor laser chip, comprising a metal bonding plate and a solder contact layer, wherein the metal bonding plate is eutectic connected to the upper surface electrode of the laser chip through the solder contact layer.

[0007] Preferably, the lower part of the metal bonding plate is eutectic connected to the heat dissipation substrate through a solder contact layer, which can transfer the heat from the metal bonding plate to the heat dissipation substrate for heat dissipation.

[0008] Preferably, the lower part of the laser chip is eutectic connected to the heat dissipation substrate through a solder contact layer. Part of the heat generated by the laser chip can be dissipated through the metal bonding plate, and the other part can be transferred to the heat dissipation substrate for heat dissipation.

[0009] Preferably, the upper surface of the heat dissipation substrate is provided with a metal layer, which is eutectic connected with the solder contact layer. The metal layer provides a stable connection with the solder contact layer.

[0010] Preferably, the metal layer is electroplated onto the heat dissipation substrate, ensuring a stable connection between the metal layer and the heat dissipation substrate.

[0011] Preferably, the metal layer serves as the electrode after encapsulation, and the electrode is connected to an external power source. The laser chip can be connected to the external power source through the electrode, thereby enabling the laser chip to be powered on.

[0012] Preferably, the metal bonding plate is made of a heat-dissipating metal material to facilitate the dissipation of heat.

[0013] Preferably, the heat dissipation substrate is a single-electrode structure, the metal bonding plate is an L-shaped structure, the end of the horizontal section of the L-shaped structure is eutectic connected to the upper part of the laser chip through a solder contact layer, and the vertical section of the L-shaped structure and the lower part of the laser chip are both connected to the metal layer through a solder contact layer.

[0014] Preferably, the heat dissipation substrate is a dual-electrode structure, the metal bonding plate is an inverted U-shaped structure, the two ends of the inverted U-shaped structure are connected to the metal layer through solder contact layers, the upper part of the laser chip is eutectic connected to the middle part of the horizontal section of the inverted U-shaped structure through solder contact layers, and the lower part of the laser chip is eutectic connected to the metal layer through solder contact layers.

[0015] Preferably, the length and width of the metal bonding plate are matched with the electrodes of the laser chip, and the size of the metal bonding plate is larger than the electrodes of the laser chip and smaller than the size of the heat dissipation substrate.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] 1. Improve heat dissipation efficiency and reduce the impact of thermal effects on laser performance to ensure performance: By improving heat dissipation efficiency, the stability and long-term reliability of the laser under high-power operation are enhanced, providing important support for the development and application of laser technology.

[0018] 2. Eliminating the metal wire bonding step reduces production costs and improves production efficiency: The modular design eliminates the metal wire bonding step required in the traditional electrical connection of lasers, simplifying the manufacturing process and saving equipment costs.

[0019] 3. Versatility: Applicable to various types and sizes of semiconductor lasers, including but not limited to DFB lasers and MOPA lasers, it can achieve high heat dissipation efficiency of the chip and has broad application prospects.

[0020] This invention is particularly suitable for meeting the need to maintain stable and efficient laser performance under high-power operating conditions, and helps to promote the advancement and application of laser technology. The implementation of this technology will significantly improve the overall performance of semiconductor lasers, reduce production costs, and provide new technical support for the widespread application of lasers. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 is a schematic diagram of the structure of the single-electrode chip of this utility model.

[0023] Figure 2 is a schematic diagram of the structure of the dual-electrode chip of this utility model.

[0024] In the diagram, 1 is the metal bonding plate, 2 is the heat dissipation substrate, 3 is the solder contact layer, and 4 is the laser chip. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] An electrical connection structure for a semiconductor laser chip is disclosed, which achieves a heat-dissipating electrical connection through a metal bonding plate and a solder contact layer, giving the chip package excellent heat dissipation performance and making it suitable for various types of semiconductor lasers. This invention includes a metal bonding plate 1 and a solder contact layer 3, wherein the metal bonding plate 1 is eutectic bonded to the electrodes of the laser chip 4 through the solder contact layer 3. The metal bonding plate 1, made of tungsten copper or other heat-dissipating metal materials with high heat dissipation properties, increases the heat dissipation surface of the chip. It is designed to connect the laser chip 4 and the heat sink substrate 2. Specifically, the metal bonding plate 1 is connected to the upper surface electrode of the laser chip 4 via a solder contact layer 3 using eutectic bonding technology. Simultaneously, it is also eutectic bonded to the metal layer on the heat sink substrate 2 via the solder contact layer 3. Therefore, this solution not only connects the heat sink substrate 2 and the laser chip 4 through the metal bonding plate 1 to provide power to the chip, but also forms a heat dissipation channel between the laser chip 4 and the heat sink, increasing the chip's heat dissipation. In other words, the eutectic bonding technology increases the chip's heat dissipation surface while providing electrical connection, allowing heat to dissipate through thermal radiation with the air, thus significantly improving heat dissipation performance. The solder contact layer 3 is located between the metal bonding plate 1 and the laser chip 4, ensuring good electrical and thermal contact between the solder contact layer 3 and the laser chip 4, further enhancing the heat dissipation effect. This invention achieves seamless integration of the metal bonding plate 1 of the electrical connection module and the laser chip 4 through eutectic technology, further reducing the impact of thermal effects on laser performance.

[0027] The upper surface of the heat dissipation substrate 2 has a metal layer, which is electroplated onto the heat dissipation substrate 2. This metal layer also serves as an electrode for the packaged COC; external power is input to the metal bonding plate 1 through this metal layer and then transmitted to the laser chip 4 to enable its operation. Simultaneously, due to the good thermal conductivity of the metal bonding plate 1, it also acts as a heat dissipation channel, transferring the heat generated by the laser chip to the metal layer on the heat dissipation substrate 2, and then to the substrate. Since the substrate is made of a material with excellent heat dissipation properties and is larger than the laser chip 4, with a much larger contact surface with air, the heat dissipation substrate can effectively reduce the chip's heat through radiative heat dissipation.

[0028] The metal bonding plate 1 is connected to the heat dissipation substrate 2 via the solder contact layer 3. Its functions are: ① To provide an electrical connection channel. External power is applied to the metal layer of the heat dissipation substrate 2 and then conducted to the metal bonding plate 1. Since the metal bonding plate 1 is eutectic bonded to the upper surface of the chip, current can be transferred through the metal bonding plate 1 to the upper surface of the laser chip 4, providing power for the chip's operation. ② To increase the heat dissipation surface. The chip generates a large amount of heat during operation. Some of this heat can be transferred through the metal bonding plate 1 to the air and the heat dissipation substrate 2 for heat dissipation, increasing the chip's heat dissipation and improving the stability of the chip's operation.

[0029] This invention eliminates the need for metal wire bonding in traditional laser electrical connections by using a metal bonding plate 1, thus saving equipment costs. Applicable to various types of semiconductor lasers, this invention achieves high heat dissipation efficiency for the chip, thereby ensuring the stability and long-term reliability of the laser under high power, providing crucial support for the development and application of laser technology.

[0030] Example 1

[0031] An electrical connection structure for a semiconductor laser chip, taking a single-electrode chip as an example, assuming the semiconductor laser chip size is 500×2300μm. 2 The heat dissipation substrate 2 has a single-electrode structure with dimensions of 2000×4000μm. 2 The relative positions of the chip and the substrate are shown in Figure 1. The design, fabrication, and specific implementation of the electrical connection between the chip and the semiconductor laser chip of this utility model include the following steps:

[0032] (1) Select a semiconductor laser chip 4 of appropriate specifications, clean the surface of the semiconductor laser chip to remove surface dirt and oxide layer, so as to ensure the reliability of metal connection in subsequent processes.

[0033] (2) Select a suitable metal bonding plate 1 as shown in Figure 1. The metal bonding plate 1 has an L-shaped structure. The horizontal end of the L-shaped structure is connected to the upper part of the laser chip 4 via a solder contact layer 3 using eutectic bonding technology. At the same time, the lower part of the laser chip 4 is also connected to the metal layer via eutectic bonding technology. The metal layer is generally plated on the heat dissipation substrate 2 using electroplating technology. The vertical section of the L-shaped structure is connected to the metal layer via the solder contact layer 3. The metal bonding plate 1 can be made of metal materials with good electrical and thermal conductivity, such as copper and aluminum. The thickness and size of the metal bonding plate 1 are adjusted according to the size and type of the chip. Generally, the thickness of the metal bonding plate 1 should be within a reasonable range, and the length and width should match the electrodes of the chip. Afterward, the metal bonding plate 1 is surface treated, such as by gold or silver plating, to improve its bonding performance with the chip electrodes and reduce resistance.

[0034] (3) Eutectic bonding of the chip and metal bonding plate 1. A certain amount of eutectic alloy material, i.e., solder contact layer 3, is coated on the contact surface between the metal bonding plate 1 and the laser chip 4, i.e., at the solder contact layer 3 on the upper surface of the chip and the metal bonding plate 1 in Figure 1. The selection of solder in solder contact layer 3 should be determined according to the material, operating temperature and application requirements of the semiconductor laser chip. When the heat generation of the laser is high, materials with good electrical and thermal conductivity are generally selected. Then, a precision alignment device is used to accurately align the ends of the laser chip and the metal bonding plate 1. During alignment, ensure that the electrodes of the chip coincide with the electrical connection part of the metal bonding plate 1 to avoid short circuits or poor contact. Finally, the chip and the metal bonding plate 1 are placed in a eutectic bonding furnace, and the process parameters such as temperature and pressure are controlled to achieve eutectic bonding. The eutectic bonding process will firmly bond the electrodes of the metal bonding plate 1 and the chip through heating and pressure, and form a reliable electrical connection.

[0035] (4) After the electrical connection is completed via the metal bonding plate 1, it replaces the traditional gold wire connection. Finally, the entire package is cured to ensure that all connections are stable and the package is secure. The electrical and optical properties are checked to ensure its reliability in the working environment.

[0036] Example 2

[0037] An electrical connection structure for a semiconductor laser chip, taking a dual-electrode chip as an example, is shown in Figure 2, with the corresponding metal bonding plate structure. It is assumed that the semiconductor laser chip 4 has a size of 500 × 2300 μm. 2 The heat dissipation substrate 2 has a dual-electrode structure and dimensions of 3000×4000μm. 2 The relative positions of the chip and the substrate are shown in Figure 2. The design, fabrication, and specific implementation of the electrical connection between the chip and the semiconductor laser chip of this utility model include the following steps:

[0038] (1) Select a semiconductor laser chip of appropriate specifications and clean the surface of the semiconductor laser chip to remove surface dirt and oxide layer in order to ensure the reliability of metal connection in subsequent processes.

[0039] (2) Select a suitable metal bonding plate 1 as shown in Figure 2. The metal bonding plate 1 has an inverted U-shaped structure. The two ends of the inverted U-shaped structure are connected to the metal layer through solder contact layer 3. The laser chip 4 is set in the middle of the horizontal section of the inverted U-shaped structure. The upper part of the laser chip 4 is eutectic bonded to the middle of the horizontal section of the inverted U-shaped structure through solder contact layer 3. The lower part of the laser chip 4 is set on the heat dissipation substrate 2 through the metal layer. The metal bonding plate 1 can be made of metal materials with good electrical and thermal conductivity, such as copper and aluminum. The thickness and size of the metal bonding plate 1 are adjusted according to the size and type of the chip. Generally speaking, the thickness of the metal bonding plate 1 should be within a reasonable range and can be adjusted according to the chip. There is no fixed range. Generally speaking, the larger the size of the metal bonding plate, the larger the contact area with air, and the better the heat dissipation effect. The length and width should match the electrodes of the chip. They can be larger or smaller than the electrodes of the chip. It is recommended that the size of the metal bonding plate be larger than the electrodes of the chip and smaller than the size of the heat dissipation substrate. Subsequently, the metal bonding plate 1 is surface treated, such as by gold or silver plating, to improve its bonding performance with the chip electrodes and reduce resistance.

[0040] (3) Eutectic bonding of the chip and metal plate. A certain amount of eutectic alloy material is coated on the contact surface between the metal bonding plate 1 and the chip, as shown in the solder contact layer 3 on the upper surface of the chip in Figure 2. The selection of the eutectic alloy should be determined according to the material, operating temperature and application requirements of the semiconductor laser chip. Then, using a precision alignment device, the laser chip and the metal bonding plate 1 are precisely aligned. During alignment, ensure that the electrodes of the chip coincide with the electrical connection parts of the metal plate to avoid short circuits or poor contact. Finally, the laser chip and the metal bonding plate 1 are placed in a eutectic bonding furnace, and the process parameters such as temperature and pressure are controlled to achieve eutectic bonding. The eutectic bonding process will firmly bond the electrodes of the metal bonding plate 1 and the laser chip 4 through heating and pressure, forming a reliable electrical connection.

[0041] (4) After the electrical connection is completed via the metal bonding plate 1, the metal bonding plate 1 replaces the traditional gold wire connection, eliminating the metal wire bonding step of traditional laser electrical connections and saving equipment costs. Finally, the entire package is cured to ensure that all connections are stable and the package is secure. The electrical and optical performance is checked to ensure its reliability in the working environment.

[0042] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. An electrical connection structure of a semiconductor laser chip, characterized by comprising: It includes a metal bonding plate (1) and a solder contact layer (3), wherein the metal bonding plate (1) is eutectic connected to the upper surface electrode of the laser chip (4) through the solder contact layer (3).

2. The electrical connection structure of the semiconductor laser chip according to claim 1, characterized in that, The lower part of the metal bonding plate (1) is eutectic connected to the heat dissipation substrate (2) through the solder contact layer (3).

3. The electrical connection structure of a semiconductor laser chip according to claim 2, wherein The lower part of the laser chip (4) is eutectic connected to the heat dissipation substrate (2) through a solder contact layer (3).

4. The electrical connection structure of the semiconductor laser chip according to claim 2 or 3, characterized in that, The upper surface of the heat dissipation substrate (2) is provided with a metal layer, and the metal layer is eutectic connected with the solder contact layer (3).

5. The electrical connection structure of the semiconductor laser chip according to claim 4, characterized in that, The metal layer is electroplated onto the heat dissipation substrate (2).

6. The electrical connection structure of a semiconductor laser chip according to claim 5, wherein The metal layer serves as the encapsulated electrode, which is connected to an external power source.

7. The electrical connection structure of the semiconductor laser chip according to claim 5 or 6, characterized in that, The metal bonding plate (1) is made of heat-dissipating metal material.

8. The electrical connection structure of a semiconductor laser chip according to claim 7, wherein The heat dissipation substrate (2) is a single electrode structure, and the metal bonding plate (1) is an L-shaped structure. The end of the horizontal section of the L-shaped structure is eutectic connected to the upper part of the laser chip (4) through the solder contact layer (3). The vertical section of the L-shaped structure and the lower part of the laser chip (4) are both connected to the metal layer through the solder contact layer (3).

9. The electrical connection structure of a semiconductor laser chip according to claim 7, wherein The heat dissipation substrate (2) has a dual-electrode structure, and the metal bonding plate (1) has an inverted U-shaped structure. The two ends of the inverted U-shaped structure are connected to the metal layer through the solder contact layer (3). The upper part of the laser chip (4) is eutectic connected to the middle part of the horizontal section of the inverted U-shaped structure through the solder contact layer (3), and the lower part of the laser chip (4) is eutectic connected to the metal layer through the solder contact layer (3).

10. The electrical connection structure of the semiconductor laser chip according to claim 8 or 9, characterized in that, The size of the metal bonding plate (1) is larger than the electrodes of the laser chip (4) and smaller than the size of the heat dissipation substrate (2).

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