Eutectic structure based on double-sided simultaneous heating

Abstract

The invention provides an eutectic structure based on double-sided simultaneous heating, and relates to the technical field of eutectic patching, the eutectic structure comprises an eutectic chip mounter, and is characterized in that a substrate feeder and a chip conveying mechanism are arranged above the eutectic chip mounter, a direction adjusting driving part is fixedly connected in the eutectic chip mounter, the direction adjusting driving part is connected with and drives a rotary heating table, and the rotary heating table is connected with the substrate feeder and the chip conveying mechanism. A bonding binding head is arranged above the eutectic chip mounter, a vacuum pump is fixedly connected in the bonding binding head, the eutectic suction nozzle is used for directly and quickly heating the top of a chip, the eutectic suction nozzle and the bottom of a substrate are cooperatively heated, an efficient double-sided heating mode is formed, a heat conduction path is greatly shortened, the overall heating efficiency is improved, and the bonding binding head is used for bonding the chip. And heat can uniformly penetrate through the chip and the solder layer, so that the problem of non-uniform heating caused by single-side heating is effectively eliminated, the eutectic alloy layer with more uniform components and a more compact structure is formed, and the thermal conductivity and the mechanical strength of a welding interface are remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of eutectic patch technology, and more particularly to a eutectic structure based on simultaneous heating of both sides. Background Technology

[0002] As a key piece of equipment in the semiconductor packaging field, the eutectic bonding machine is essentially a high-precision and high-reliability bonding process that attaches chips to the substrate or housing surface. This process utilizes the synergistic effect of high temperature and pressure to form atomic-level metal bonds between the chip and the substrate, thereby achieving excellent thermal conductivity and mechanical connection strength. It is especially suitable for semiconductor devices with stringent requirements for heat dissipation and reliability.

[0003] However, in traditional eutectic bonding machines, the eutectic process mainly relies on a single-sided heating structure on the bottom of the substrate, combined with pressure applied to the chip by the eutectic nozzle above, to promote bonding at the bonding interface. This single-sided heating method has problems such as low heat conduction efficiency and uneven heating of the substrate and chip. If the temperature control is too high, it can easily lead to thermal damage to the substrate; if it is too low, it can easily cause insufficient heating of the chip bonding interface, affecting the formation quality and bonding strength of the eutectic layer. In addition, when dealing with bonding scenarios where multiple chips are integrated on the same substrate, if one of the chips is damaged and needs to be replaced, it is not possible to remove it by local heating. Instead, the entire substrate and all the chips on it must be heated as a whole to remelt the solder before the faulty chip can be removed. This process is not only cumbersome, but also increases the risk of thermal damage to the substrate and other intact chips due to repeated thermal cycling, affecting the overall packaging yield and reliability. Summary of the Invention

[0004] This invention provides a eutectic structure based on simultaneous heating from both sides to solve the problems in traditional eutectic bonding machines. The eutectic process mainly relies on a single-sided heating structure on the bottom of the substrate, combined with pressure applied to the chip by the eutectic nozzle above to promote bonding at the solder interface. This single-sided heating method suffers from low heat conduction efficiency and uneven heating between the substrate and the chip. If the temperature is too high, it can easily lead to thermal damage to the substrate; if it is too low, it can easily cause insufficient heating at the chip solder interface, affecting the formation quality and bonding strength of the eutectic layer. Furthermore, in soldering scenarios where multiple chips are integrated on the same substrate, if one chip is damaged and needs replacement, local heating for removal is not possible. Instead, the entire substrate and all chips on it must be heated as a whole to remelt the solder before the faulty chip can be removed. This process is not only cumbersome but also increases the risk of thermal damage to the substrate and other intact chips due to repeated thermal cycling, affecting the overall packaging yield and reliability.

[0005] This invention provides a eutectic structure based on simultaneous heating on both sides, specifically including: a eutectic bonding machine, characterized in that: a substrate feeder and a chip conveying mechanism are provided above the eutectic bonding machine; an aligning drive is fixedly connected inside the eutectic bonding machine; the aligning drive is connected to and drives a rotary heating stage; a bonding head is provided above the eutectic bonding machine; a vacuum pump is fixedly connected inside the bonding head; a chip heater is installed at the bottom of the bonding head; a nozzle assembly base is fixedly connected below the chip heater; a four-hole nozzle is inserted into the nozzle assembly base; the eutectic bonding machine is connected to a chip assembly platform, which is located to the right of the rotary heating stage; and the nozzle assembly base is connected to the vacuum pump through a pipe.

[0006] Furthermore, the tube of the four-hole suction nozzle is inserted into the nozzle assembly base, and a clamp is provided at the bottom of the nozzle assembly base to tightly hold the tube of the four-hole suction nozzle.

[0007] Furthermore, the lower end of the four-hole nozzle has four suction holes arranged in a straight line, and the suction holes are connected to the vacuum pump through the insertion tube of the four-hole nozzle and the air hole inside the nozzle mounting base.

[0008] Furthermore, it also includes a single-hole suction nozzle, the insertion tube of which is inserted into the nozzle assembly base, and a suction hole is provided at the lower end of the single-hole suction nozzle.

[0009] Furthermore, the outer edge of the rotary heating stage is provided with two unit eutectic stages, and a substrate heating plate is fixedly connected above the unit eutectic stages.

[0010] Furthermore, a micro suction hole is provided in the center of the substrate heating plate, and the micro suction hole is connected to a vacuum pump located at the bottom of the substrate heating plate.

[0011] Furthermore, a micro suction hole is provided on the upper surface of the chip assembly platform, and the bottom of the micro suction hole is connected to a vacuum pump located at the bottom of the chip assembly platform.

[0012] This invention provides a eutectic structure based on simultaneous heating from both sides, which has the following beneficial effects: This invention uses a eutectic nozzle to directly and rapidly heat the chip from the top, working in conjunction with bottom heating of the substrate to form a highly efficient double-sided heating mode. This not only significantly shortens the heat conduction path and improves the overall heating efficiency, but also allows heat to penetrate the chip and solder layer evenly, effectively eliminating the problem of uneven heating caused by single-sided heating. The result is the formation of a more uniform and denser eutectic alloy layer, which significantly improves the thermal conductivity and mechanical strength of the solder interface.

[0013] In addition, using the nozzle as a direct heat source to act on the chip enables precise and rapid response and control of the welding interface temperature. This avoids the overall overheating or underheating of the substrate caused by the long heat path and slow response in traditional methods, reduces the risk of substrate damage due to excessive heating, and also ensures that the eutectic reaction is sufficient and consistent, greatly improving the tolerance of the process window and the production yield.

[0014] Furthermore, it enables localized and selective processing of specific chips on the substrate. When a failed chip in a multi-chip module needs to be replaced, the four-hole nozzle located at the bottom of the nozzle mounting base can be removed and a single-hole nozzle can be installed. The single-hole nozzle is used to heat the removed chip, achieving localized micro-area heating, melting the specific solder joint and removing it. This avoids the repeated thermal cycling of the entire substrate and all healthy chips during traditional repairs, greatly reducing the probability of damage to surrounding devices due to secondary heating. This makes the repair process simple, safe, and cost-effective, and is suitable for substrate materials that are more sensitive to heat.

[0015] In addition, the four-hole nozzle has four suction holes. With the cooperation of the four suction holes, it can simultaneously pick up four chips that are transferred by the chip delivery mechanism to the chip assembly stage and place them on the substrate for heating, thereby improving the efficiency of multi-chip synchronous welding. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments will be briefly described below.

[0017] The accompanying drawings described below are only related to some embodiments of the invention and are not intended to limit the invention.

[0018] In the attached diagram: Figure 1 A schematic diagram of the overall structure of this application is shown; Figure 2 This application shows Figure 1 A top-view structural diagram; Figure 3 A schematic diagram of the structure of the rotary heating stage of this application is shown; Figure 4 A schematic diagram of the structure at the bottom of the bonding head of this application is shown; Figure 5 A schematic diagram of the structure of the four-hole nozzle of this application is shown; Figure 6 A schematic diagram of the structure when the single-hole nozzle of this application is replaced is shown.

[0019] Figure label: 1. Eutectic mounter; 2. Substrate feeder; 3. Orientation drive; 4. Rotary heating stage; 401. Unit eutectic stage; 402. Substrate heating plate; 5. Bonding tie head; 6. Chip heater; 7. Chip assembly stage; 8. Nozzle assembly base; 9. Four-hole nozzle; 10. Chip conveying mechanism; 11. Single-hole nozzle. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the described embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1: Please refer to Figures 1 to 6 : This invention proposes a eutectic structure based on simultaneous heating on both sides, comprising: a eutectic bonding machine 1, characterized in that a substrate feeder 2 and a chip conveying mechanism 10 are provided above the eutectic bonding machine 1; an adjustment drive 3 is fixedly connected inside the eutectic bonding machine 1, the adjustment drive 3 is connected to and drives a rotary heating stage 4; a bonding head 5 is provided above the eutectic bonding machine 1, a vacuum pump is fixedly connected inside the bonding head 5, a chip heater 6 is installed at the bottom of the bonding head 5, a nozzle mounting base 8 is fixedly connected below the chip heater 6, and a four-hole nozzle 9 is inserted into the nozzle mounting base 8; eutectic bonding... The machine 1 is connected to a chip assembly platform 7, which is located to the right of the rotary heating platform 4. The nozzle mounting base 8 is connected to a vacuum pump through a pipe. The chip is directly and quickly heated from the top by the nozzle, working in conjunction with the bottom heating of the substrate to form an efficient double-sided heating mode. This not only significantly shortens the heat conduction path and improves the overall heating efficiency, but also allows the heat to penetrate evenly between the chip and the solder layer, effectively eliminating the problem of uneven heating caused by single-sided heating. By using the nozzle as a direct heat source to act on the chip, it is possible to achieve precise and rapid response and control of the solder interface temperature.

[0022] In this embodiment, the tube of the four-hole nozzle 9 is inserted into the nozzle mounting base 8. The bottom of the nozzle mounting base 8 is provided with a clamp that tightly clamps the tube of the four-hole nozzle 9. The lower end of the four-hole nozzle 9 has four suction holes arranged in a straight line. The suction holes are connected to the vacuum pump through the tube of the four-hole nozzle 9 and the air hole inside the nozzle mounting base 8. The four-hole nozzle 9 has four suction holes. With the cooperation of the four suction holes, it can simultaneously pick up four chips that are transferred by the chip delivery mechanism to the chip assembly platform 7 and place them on the substrate for heating, thereby improving the efficiency of multi-chip synchronous welding.

[0023] In this embodiment, the outer edge of the rotary heating stage 4 is provided with two unit eutectic stages 401. A substrate heating plate 402 is fixedly connected above the unit eutectic stage 401. A micro-perforation is opened in the center of the substrate heating plate 402, and the micro-perforation is connected to a vacuum pump located at the bottom of the substrate heating plate 402. While the substrate is heated by the substrate heating plate 402, the substrate is adsorbed by negative pressure through the cooperation of the vacuum pump at the bottom of the substrate heating plate 402 and the micro-perforation, so as to prevent the substrate from sliding and shifting during the eutectic bonding process.

[0024] In this embodiment, a micro suction hole is provided on the upper surface of the chip assembly platform 7, and the bottom of the micro suction hole is connected to a vacuum pump located at the bottom of the chip assembly platform 7. Through the cooperation of the micro perforation above the chip assembly platform 7 and the vacuum pump, the chips are placed and arranged stably, making them less likely to slip, thereby improving the stability of chip transportation and feeding.

[0025] Example 2, based on Example 1, also includes a single-hole suction nozzle 11. The tube of the single-hole suction nozzle 11 is inserted into the nozzle mounting base 8. The lower end of the single-hole suction nozzle 11 has a suction hole. When it is necessary to replace a failed chip in a multi-chip module, the four-hole suction nozzle 9 located at the bottom of the nozzle mounting base 8 can be removed and the single-hole suction nozzle 11 can be installed. At the same time, the single-hole suction nozzle 11 and the substrate heating plate 402 are heated to heat the chip and the substrate respectively. The temperature of the substrate heating plate 402 is lower than that of the single-hole suction nozzle 11. The single chip to be removed is heated by the single-hole suction nozzle 11 to achieve local micro-area heating. At the same time, specific solder joints are melted and removed, avoiding the repeated thermal cycling of the entire substrate and all healthy chips in traditional repair.

[0026] The working principle of this embodiment is as follows: First, the substrate is transported by the substrate feeder 2 and precisely positioned onto a unit eutectic stage 401 on the rotary heating table 4. The chips are transported by the chip conveying mechanism 10 and precisely positioned above the chip assembly stage 7. Then, the chips on the top of the chip assembly stage 7 are picked up by the four-hole suction nozzle 9 at the bottom of the bonding head 5 and transferred to the upper surface of the substrate above the substrate heating plate 402, so that the bottom of the chip is attached to the top of the substrate. The four-hole suction nozzle 9 is heated by the chip heater 6, and the chip is picked up by negative pressure adsorption. Then, the four-hole suction nozzle 9 carries the chip to the top of the substrate, and after precise positioning, it is pressed downward. During the pressing process, the four-hole suction nozzle 9 and the unit eutectic stage 401 heat the chip and the substrate in both directions synchronously, so that the solder layer quickly and uniformly reaches the eutectic temperature and completes the metallurgical bonding. After welding, each heating component stops working, and the solder joints cool and solidify. Throughout the process, the rotating heating table 4 can switch positions under the drive of the directional drive 3 to achieve parallel operation of loading and welding. When maintenance is required, the four-hole suction nozzle 9 located at the bottom of the suction nozzle assembly seat 8 is disassembled and a single-hole suction nozzle 11 is installed. At the same time, the single-hole suction nozzle 11 and the substrate heating plate 402 are heated to heat the chip and the substrate respectively, and the temperature of the substrate heating plate 402 is lower than that of the single-hole suction nozzle 11. The single chip is heated by the single-hole suction nozzle 11 to achieve local micro-area heating. At the same time, the solder joints of the specific chip are melted and disassembled and discarded to the waste area. Then, the bonding head 5, together with the single-hole suction nozzle 11, picks up the new chip again and welds it into the substrate, completing the replacement process of the scrapped chip.

[0027] The following points should be noted in this article: 1. The accompanying drawings of the embodiments disclosed herein only relate to the structures involved in the embodiments disclosed herein; other structures can be referred to in a general design.

[0028] 2. Where there is no conflict, the embodiments of this disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0029] The above are merely specific embodiments of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A eutectic structure based on simultaneous heating from both sides, including: A eutectic bonding machine (1) is characterized in that a substrate feeder (2) and a chip conveying mechanism (10) are provided above the eutectic bonding machine (1), an adjustment drive (3) is fixedly connected inside the eutectic bonding machine (1), the adjustment drive (3) is connected to and drives a rotary heating table (4), a bonding head (5) is provided above the eutectic bonding machine (1), a vacuum pump is fixedly connected inside the bonding head (5), a chip heater (6) is installed at the bottom of the bonding head (5), a nozzle mounting base (8) is fixedly connected below the chip heater (6), a four-hole nozzle (9) is inserted inside the nozzle mounting base (8), a chip assembly platform (7) is connected to the eutectic bonding machine (1), the chip assembly platform (7) is located to the right of the rotary heating table (4), and the nozzle mounting base (8) is connected to the vacuum pump through a pipe.

2. The eutectic structure based on simultaneous heating on both sides according to claim 1, characterized in that, The tube of the four-hole suction nozzle (9) is inserted into the nozzle assembly base (8). The bottom of the nozzle assembly base (8) is provided with a clamp that tightly clamps the tube of the four-hole suction nozzle (9).

3. The eutectic structure based on simultaneous heating on both sides according to claim 2, characterized in that, The lower end of the four-hole suction nozzle (9) has four suction holes arranged in a straight line. The suction holes are connected to the vacuum pump through the insertion tube of the four-hole suction nozzle (9) and the air hole inside the suction nozzle mounting base (8).

4. The eutectic structure based on simultaneous heating on both sides according to claim 3, characterized in that, It also includes a single-hole suction nozzle (11), the insertion tube of which is inserted into the nozzle assembly base (8), and a suction hole is provided at the lower end of the single-hole suction nozzle (11).

5. The eutectic structure based on simultaneous heating on both sides according to claim 4, characterized in that, The rotating heating stage (4) has two unit eutectic stages (401) on its outer edge, and a substrate heating plate (402) is fixedly connected above the unit eutectic stages (401).

6. The eutectic structure based on simultaneous heating on both sides according to claim 5, characterized in that, The substrate heating plate (402) has a micro suction hole in the center, which is connected to a vacuum pump located at the bottom of the substrate heating plate (402).

7. The eutectic structure based on simultaneous heating on both sides according to claim 6, characterized in that, The chip assembly platform (7) has a micro suction hole on its upper surface, and the bottom of the micro suction hole is connected to a vacuum pump located at the bottom of the chip assembly platform (7).

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