Chip welding device and welding method

Abstract

The invention discloses a chip welding device and a welding method, and belongs to the technical field of electronic component production equipment. Which comprises a heat source and a chip (2), and is characterized in that a closed working cavity (6) is arranged outside the heat source, the working cavity (6) comprises two sections which are symmetrically arranged, the junction of the two ends is the highest point of the working cavity (6), and the chip (2) moves relative to the working cavity (6) in the working cavity (6) and passes through the whole working cavity (6). According to the chip welding device and the chip welding method, the characteristic that hot air ascends and cold air descends after the temperature of the heat source rises is utilized, two sections with the temperature increasing and decreasing naturally are formed in the working cavity, preheating, welding and cooling are achieved in the process that the chip passes through the working cavity, and the situation that in the prior art, when preheating and welding of the chip are achieved, the welding efficiency is high is avoided. And main heaters need to be arranged respectively.

Description

Technical Field

[0001] The invention discloses a chip welding device and a welding method, belonging to the technical field of electronic component production equipment. Background Art

[0002] Chips are usually provided with many pins, and the chip pins are electrically connected to the circuit board through soldering. In the prior art, when soldering the chip, it is generally necessary to sequentially place the lower connecting piece, the chip and the upper connecting piece on the bottom connecting piece of the graphite boat, and place soldering pieces between the bottom connecting piece and the lower connecting piece, between the lower connecting piece and the chip, and between the upper connecting piece and the chip. Solder oil needs to be applied between the soldering piece and the lower connecting piece, between the soldering piece and the chip, and between the soldering piece and the upper connecting piece, and finally soldering is performed.

[0003] In the prior art, the graphite boat is generally sent into a vacuum furnace to complete the welding. The defects of this welding method are: (1) It is necessary to set up an assembly and conveying line for the graphite boat (such as the technical solution disclosed in the Chinese invention patent with application number 202211463686.9, application date November 17, 2022, and patent name "A bridge assembly line"), and its overall cost is relatively high. (2) When heating, the existing method actually heats the graphite boat first, and then further heats the chip through the graphite boat, so it has the defect of high energy consumption. (3) After the chip is welded, it needs to be cooled down. Although the natural cooling method has high reliability, it takes a long time. If a special cooling device is used for comparison, it will not only increase the production cost, but also easily damage the chip if the temperature difference between the cooling temperature and the welding temperature is large.

[0004] The Chinese utility model patent with application number 200420002311.3 and application date of February 3, 2004, and patent name "gradual heating type solder ball welding device" discloses a technical solution, in which a "gradual heating type solder ball welding device" is disclosed. A conveyor chain is provided in the device, and a preheating zone, a heating zone, a melting zone and a cooling zone are formed on the conveyor chain. The temperature from the preheating zone to the melting zone increases successively, and the temperature from the melting zone to the cooling zone decreases successively. In the process of transmission through the conveyor chain, the chip is welded and cooled. However, this method requires the heating devices to be arranged in sequence along the conveyor chain, and its structure is also relatively complicated. Summary of the invention

[0005] The technical problem to be solved by the present invention is: to overcome the deficiencies of the prior art, to provide a chip welding device and a welding method, to use the heat of the working chamber to complete the welding of the chip, to achieve full utilization of the heat, and to reduce energy consumption.

[0006] The technical solution adopted by the present invention to solve its technical problems is: the chip welding device is characterized by: including a working chamber and a heat source for increasing the temperature in the working chamber, the temperature in the upper part of the working chamber gradually increases from bottom to top, and at least one power device is provided, the power device is used to realize the relative lifting and lowering of the working chamber and the chip, and the welding is completed when the chip rises relatively to the top of the working chamber.

[0007] Preferably, the heat source comprises a main heater, and the main heater is arranged in the middle of the inner side of the working chamber.

[0008] Preferably, the heat source further includes a plurality of auxiliary heaters, and the plurality of auxiliary heaters are arranged on a rising path of the chip relative to the working chamber.

[0009] Preferably, the power device drives the chip to gradually rise and then gradually descend in the working chamber, and the auxiliary heater is arranged on the power device.

[0010] Preferably, the power device includes multiple robotic arms, and the chip is transferred by adjacent robotic arms, one group of robotic arms gradually transfers the chip from bottom to top until the chip is transferred to the top of the working chamber, and another group of robotic arms gradually transfers the chip from top to bottom.

[0011] Preferably, a cold air blowing port is provided at the lower portion of the working chamber, and the cold air blowing port is used to cool the chip after welding.

[0012] Preferably, a vacuum assembly is provided at the inner upper part of the working chamber, and after the chip rises relatively to the top of the working chamber, the vacuum assembly forms a vacuum environment around the chip, and the chip is welded inside the vacuum assembly.

[0013] Preferably, the vacuum pumping assembly is connected to the bottom of the working chamber through an exhaust pipeline, and a welding oil filter is provided on the exhaust pipeline.

[0014] A chip welding method, characterized in that it comprises the following steps: Step 1: The heat source raises the temperature in the working chamber and makes the temperature of the upper part of the working chamber reach the temperature required for chip welding, and the chip enters the lower part of the working chamber; Step 2, the chip rises relative to the working chamber. After the chip rises to the upper part of the working chamber, the welding material of the chip melts and the welding is completed; Step 3: The chip and the working chamber move relative to each other and move downward along the working chamber to the bottom of the working chamber.

[0015] Compared with the prior art, the present invention has the following beneficial effects: In the chip welding device and welding method, the characteristics of hot air rising and cold air falling after the heat source is heated are utilized to naturally form a temperature distribution state with increasing temperature from bottom to top in the working chamber. The chip is welded and cooled in the process of passing through the working chamber, avoiding the disadvantage of the prior art that several heaters need to be set separately when preheating and welding the chip. Using hot air as a heat source to heat the solder ball greatly reduces heat loss, energy consumption and production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of chip welding device embodiment 1.

[0017] Figure 2 This is a schematic structural diagram of embodiment 2 of the chip welding device.

[0018] Figure 3 This is a schematic structural diagram of Example 3 of the chip welding device.

[0019] Figure 4 This is a schematic structural diagram of Example 6 of the chip welding device.

[0020] Among them: 1, inlet 2, chip 3, shell 4, cold air blowing port 5, main heater 6, working chamber 7, outlet 8, air extraction port 9, robotic arm 10, circulation chamber 11, auxiliary heater. DETAILED DESCRIPTION

[0021] Figure 1~2 The best embodiment of the present invention is shown below in conjunction with the attached Figures 1 to 4 The present invention is further described.

[0022] Embodiment 1: like Figure 1 As shown, a chip welding device (hereinafter referred to as welding device) includes a shell 3, the interior of the shell 3 is a working chamber 6, a main heater 5 is arranged in the working chamber 6, and an insulation layer is arranged on the outer wall or the inner wall of the working chamber 6 to ensure that the heat released by the main heater 5 is retained in the working chamber 6 to the greatest extent.

[0023] Openings are provided at both ends of the surface of the shell 3 : an inlet 1 and an outlet 7 . After the chip 2 enters the working chamber 6 from the inlet 1 , it moves along the contour of the working chamber 6 to the other end of the working chamber 6 and is output from the outlet 7 .

[0024] In the present welding device, the housing 3 is preferably an arched structure with low ends and high middle. An air extraction port 8 is provided at the upper part of the housing 3, and a cold air blowing port 4 is provided at the lower part of the housing 3. Since the specific gravity of hot air is less than that of cold air, the heat generated by the main heater 5 during operation makes the highest point of the working chamber 6 the highest temperature point, and the temperature of the working chamber 6 gradually decreases from top to bottom. The gas generated during the welding process is extracted from the air extraction port 8, and the air extraction port 8 is connected to the cold air blowing port 4 through an air extraction pipeline. A welding oil filter is provided on the air extraction pipeline. After the welding oil is filtered, the nitrogen extracted from the air extraction port 8 is cooled and then sent to the working chamber 6 through the cold air blowing port 4 again to cool the chip 2 after welding.

[0025] Through temperature simulation inside the shell 3, it can be confirmed that although the temperature distribution in the working chamber 6 inside the shell 3 gradually decreases from high to low, and the temperature at the highest point in the working chamber 6 is lower than the temperature of the main heater 5, and when the temperature of the main heater 5 is 600°C, the top of the shell 3 can reach a temperature of 350°C for realizing chip 2 welding.

[0026] In this embodiment, a robot arm 9 is provided at the bottom of the chip 2, and a chip bracket is provided on the robot arm 9, and the chip 2 is driven by the chip bracket to move along the contour of the working chamber 6 in the working chamber 6. And during the welding process, nitrogen is flushed into the housing 3 to achieve welding in an oxygen-free environment. Each robot arm 9 can be composed of a vertical telescopic component and a horizontal telescopic component. The robot arm 9 holds the chip 2 up and then moves to the next robot arm 9, and the chip 2 is transferred upward in turn. After welding, the chip 2 is transferred downward by the robot arm 9. The robot arm 9 that transfers the chip 2 upward and the robot arm 9 that transfers the chip 2 downward can be symmetrically arranged on both sides of the working chamber 6, or they can be arranged on the same side of the working chamber 6.

[0027] The specific working process and working principle are as follows: After the chip 2 enters the working chamber 6 through the entrance 1, it rises under the drive of the robot arm 9. During the rising process, the chip 2 is first preheated. When the chip 2 rises to the top of the working chamber 6, the chip 2 is located at the highest temperature in the working chamber 6, and the temperature there is sufficient to melt the solder ball and complete the welding.

[0028] Then the robot arm 9 continues to drive the chip 2 to move downward along the other side of the working chamber 6. During the downward movement of the chip 2, as its height gradually decreases, the temperature of the area where it is located gradually decreases, thereby completing the cooling of the chip 2. Finally, the robot arm 9 drives the chip 2 to be output from the outlet 7. When the chip 2 moves to the outlet 7, the cooler is output to the chip 2 through the cold air blowing port 4, further accelerating the cooling of the chip 2.

[0029] As can be seen from the above, in the present welding device, the working chamber 6 is used as a heat source, and the characteristics of hot air rising and cold air falling are utilized to naturally form two sections of increasing and decreasing temperature in the working chamber 6. The junction of the two sections is the top of the working chamber 6, that is, the position with the highest temperature in the working chamber 6. Therefore, the chip 2 can be preheated and welded during the rising process, and the chip 2 can be cooled down during the descending process after the welding is completed. Therefore, the disadvantage of the prior art that several heaters need to be set separately when preheating and welding the chip 2, resulting in heat waste, is avoided. At the same time, air is used as a heat source to heat the solder ball, so that the heat is reused in the working chamber 6, reducing heat loss and greatly reducing energy consumption.

[0030] Embodiment 2: like Figure 2 As shown, the difference between this embodiment and embodiment 1 is that the position of the chip 2 is relatively fixed, and a mechanical arm 9 is set at the bottom of the shell 3. The mechanical arm 9 drives the entire shell 3 to achieve relative movement with the chip 2 to complete the preheating, welding and cooling of the chip 2.

[0031] Embodiment 3: like Figure 3 As shown, this embodiment is further improved on the basis of embodiment 2, and a fan-shaped circulation chamber 10 is provided at the bottom of the working chamber 6, and the two ends of the circulation chamber 10 are respectively connected to the two ends of the working chamber 6 at the bottom of the working chamber 6, so that the working chamber 6 forms a closed loop. In the closed loop space formed by the connection between the working chamber 6 and the circulation chamber 10, a plurality of mechanical arms 9 are provided, and all the mechanical arms 9 circulate in the closed loop space to realize the transfer with the two external conveyor chains.

[0032] Embodiment 4: The difference between this embodiment and embodiment 1 is that a conveyor chain is arranged outside the shell 3, and the conveyor chain is respectively located at the entrance 1 and the exit 7. The chip 2 is placed on the surface of the conveyor chain for transmission. When the chip 2 enters through the entrance 1, the chip 2 is transferred between the robot arm 9, and the robot arm 9 continues to drive the chip 2 to move in the working chamber 6. After the chip 2 completes preheating, welding and cooling in the working chamber 6, it is output through the exit 7, and the conveyor chain arranged at the exit 7 continues to output the chip 2.

[0033] Embodiment 5: This embodiment is further improved on the basis of the embodiment 4. An annular conveying chain is arranged in the closed-loop space formed by the working chamber 6 and the circulation chamber 10. The robot arm 9 is installed on the conveying chain, and the conveying chain drives the robot arm 9 to operate.

[0034] Embodiment 6: The difference between this embodiment and embodiment 1 is that: Figure 4As shown, in this embodiment, on the inner wall of the shell 3, a plurality of auxiliary heaters 11 are arranged in sequence and at intervals along the rising path of the chip 2. The chip 2 is heated by the auxiliary heaters 11 in cooperation with the main heater 5, so that the chip 2 quickly reaches the preset temperature of the corresponding height when it rises to the corresponding height.

[0035] In addition, the heating method of the central main heater 5 and multiple auxiliary heaters 11 is used to heat the chip 2 more gently during the entire heating process, compared with the traditional method of heating only at multiple points, eliminating the adverse effects of the stepped temperature distribution on welding under the traditional heating method.

[0036] Embodiment 7: The difference between this embodiment and embodiment 1 is that in this embodiment, the ascending route and the descending route of the chip 2 are not in the same plane. After the chip 2 rises to the highest point on the inner wall of the shell 3 and completes heating, it rotates 180° in the opposite direction and descends on another trajectory parallel to the ascending route, thereby achieving cooling of the chip 2.

[0037] Embodiment 8: The difference between this embodiment and embodiment 6 is that in this embodiment, the ascending and / or descending route of the chip 2 is not arranged in an arc or straight line, but in a stepped ascending and descending route. The auxiliary heater 11 is arranged on a driving device for conveying the chip 2 step by step.

[0038] Embodiment 9: The difference between this embodiment and embodiment 1 is that in this embodiment, the high-temperature gas generated during the heating of the chip 2 is extracted from the exhaust port 8 and then introduced again from the bottom of the housing 3 to achieve the circulation of hot air flow and nitrogen.

[0039] Embodiment 10: In this embodiment, a vacuum pumping assembly is provided in the housing 3. After the chip 2 rises relatively to the top of the working chamber 6, the vacuum pumping assembly forms a vacuum environment around the chip 2, and the chip 2 is welded inside the vacuum pumping assembly. Specifically, the vacuum pumping assembly is composed of at least two relatively movable shell assemblies, or a shell and a bottom plate. After the chip 2 moves to the top of the working chamber 6, the vacuum pumping assembly is closed on the outside of the chip 2 and then vacuumed to form a vacuum environment, and the chip 2 is welded inside the vacuum pumping assembly.

[0040] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A chip welding device, characterized in that: The invention comprises a working chamber (6) and a heat source for increasing the temperature in the working chamber (6), wherein the temperature in the upper part of the working chamber (6) gradually increases from bottom to top. At least one power device is also provided, wherein the power device is used to realize relative lifting and lowering of the working chamber (6) and the chip (2), and welding is completed when the chip (2) rises relatively to the top of the working chamber (6).

2. The chip bonding device according to claim 1, characterized in that: The heat source comprises a main heater (5), and the main heater (5) is arranged in the middle of the inner side of the working chamber (6).

3. The chip bonding device according to claim 2, characterized in that: The heat source further comprises a plurality of auxiliary heaters (11), wherein the plurality of auxiliary heaters (11) are arranged on a path along which the chip (2) rises relative to the working chamber (6).

4. The chip bonding device according to claim 3, characterized in that: The power device drives the chip (2) to gradually rise and then gradually descend in the working chamber (6), and the auxiliary heater (11) is arranged on the power device.

5. The chip bonding device according to claim 1, characterized in that: The power device comprises a plurality of mechanical arms (9), and the chip (2) is transferred by adjacent mechanical arms (9), wherein one group of mechanical arms (9) gradually transfers the chip (2) from bottom to top until the chip (2) is transferred to the top of the working chamber (6), and another group of mechanical arms (9) gradually transfers the chip (2) from top to bottom.

6. The chip bonding device according to claim 1, characterized in that: A cold air blowing port (4) is provided at the lower part of the working chamber (6), and the cold air blowing port (4) is used to cool the chip (2) after welding.

7. The chip bonding device according to claim 1, characterized in that: A vacuum pumping component is provided at the upper inner portion of the working chamber (6); after the chip (2) rises relatively to the top of the working chamber (6), the vacuum pumping component forms a vacuum environment around the chip (2), and the chip (2) is welded inside the vacuum pumping component.

8. The chip bonding device according to claim 7, characterized in that: The vacuum pumping assembly is connected to the bottom of the working chamber (6) via an exhaust pipeline, and a welding oil filter is provided on the exhaust pipeline.

9. A welding method implemented by using the chip welding device according to any one of claims 1 to 8, characterized in that: The steps include: Step 1: A heat source raises the temperature in the working chamber (6) and makes the temperature of the upper part of the working chamber (6) reach the temperature required for welding the chip (2), and the chip (2) enters the lower part of the working chamber (6); Step 2, the chip (2) rises relative to the working chamber (6), and after the chip (2) rises to the upper part of the working chamber (6), the welding material of the chip (2) melts to complete the welding; Step 3: The chip (2) and the working chamber (6) move relative to each other and move downward along the working chamber (6) to the bottom of the working chamber (6).

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