Paster pressure head capable of rapidly heating and cooling

Abstract

The utility model discloses a chip mounting pressure head capable of rapidly heating and cooling, which comprises a Z-axis lifting mechanism, a U-axis rotation mechanism arranged on the Z-axis lifting mechanism, a pressure sensor connected to the lower end of the U-axis rotation mechanism, a pulse heating head arranged at the lower end of the pressure sensor, and a jig adsorbed to the lower end of the pulse heating head and used for adsorbing a chip, and a rapid cooling channel for introducing a cooling medium and a vacuum cavity for vacuumizing the adsorption jig and the chip are arranged in the pulse heating head. Pulse heating can be realized through the pulse heating head, the bonding time is shortened, and the bonding quality is improved; the bonding pressure can be monitored in real time through the pressure sensor, and the defects of chip and substrate damage caused by overpressure and insufficient pressure which causes insufficient soldering and bridging are overcome; and the pressure head can be rapidly cooled through the rapid cooling channel.

Description

Technical Field

[0001] The utility model belongs to chip production equipment, and in particular relates to a chip pressing head capable of rapidly raising and lowering the temperature. Background Art

[0002] In the production process of semiconductor chips, the process shrinkage has become very difficult and the cost-effectiveness has encountered challenges. The arrival of multi-chip packaging technology has become the key to further improving chip performance. Flip chip bonding technology has become one of the most important technologies for advanced multi-chip packaging. Today, the most common flip chip bonding packaging technology based on solder balls is reflow soldering. The main process of reflow soldering is: first, the solder joints on the chip are stained with flux or a certain amount of flux is sprayed on the solder joint area on the substrate, and then the chip is placed on the substrate relatively accurately with a patch pressure head that quickly rises and falls. Then, the chip and the substrate are placed in a reflow oven as a whole, and then the temperature of the reflow oven is controlled to achieve the welding of the chip and the substrate. The entire reflow soldering time is usually 5 to 10 minutes. However, there are not too many restrictions on the chip and the substrate during the reflow process, which will cause the warping of the chip and the substrate to be unable to be effectively controlled, so that the distance between the chip and the substrate changes greatly under the chip surface. Excessive warping will lead to the two most common defects of cold solder joints and bridging. Therefore, the yield rate of complex multi-chip bonding based on reflow soldering may be very low, making reflow soldering no longer the most suitable bonding method. With the emergence of thermal compression bonding process, it has begun to gradually replace the reflow soldering process. However, when using the thermal compression bonding process, how to quickly increase or decrease the temperature of the chip pressing head to improve the efficiency of the thermal compression bonding process is an urgent problem that needs to be solved. Utility Model Content

[0003] The technical problem to be solved by the utility model is to provide a patch pressure head with rapid temperature rise and fall, which can realize rapid temperature rise and fall in the patch process.

[0004] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0005] A chip pressing head with rapid temperature rise and fall comprises a Z-axis lifting mechanism, a U-axis rotation mechanism arranged on the Z-axis lifting mechanism, a pressure sensor connected to the lower end of the U-axis rotation mechanism, a pulse heating head arranged at the lower end of the pressure sensor, and a fixture for adsorbing chips adsorbed on the lower end of the pulse heating head. The pulse heating head is provided with a rapid cooling channel for passing a cooling medium and a vacuum air channel for vacuuming the adsorption fixture and chips.

[0006] The Z-axis lifting mechanism comprises a motor support seat, a Z-axis screw motor arranged on the motor support seat, and a fixing frame matched with the screw of the Z-axis screw motor through a nut, and the U-axis rotation mechanism is fixed on the fixing frame.

[0007] The Z-axis lifting mechanism also includes a lifting guide mechanism, which includes a pair of sliders arranged on both sides of the fixed frame and a pair of slide rails respectively arranged to cooperate with the sliders, and the slide rails are connected and fixed to the motor support seat.

[0008] It also includes a gantry, and the Z-axis lifting mechanism is arranged on the gantry.

[0009] The fixture includes a connecting plate and a pressure head arranged at the lower end of the connecting plate and matching the chip specifications. The connecting plate is provided with an I-shaped air groove, and the pressure head is provided with an adsorption hole connected to the air groove. Two vacuum air ducts are provided in the pulse heating head, one of which is connected to the vacuum suction holes distributed on the end face of the pulse heating head to adsorb the upper surface of the connecting plate, and the other is connected to the air groove and the adsorption hole.

[0010] The utility model adopts a patch pressure head with rapid temperature rise and fall, which has the following advantages:

[0011] 1. Through pulse heating, the temperature can be quickly raised to melt the solder paste to complete the bonding, and then the temperature can be quickly lowered to form a solder joint, shortening the bonding time and improving the bonding quality;

[0012] 2. The bonding pressure is monitored in real time through the pressure sensor, which can prevent damage to the chip and substrate caused by overpressure, and defects such as cold solder joints and bridging caused by insufficient pressure;

[0013] 3. By introducing cooling media such as compressed gas, the heated pulse heating head can be cooled quickly, which helps to avoid the glue solidifying during the dipping process before the next chip is heat-bonded. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is described in detail below with reference to the accompanying drawings and specific implementation methods:

[0015] Figure 1 , Figure 2 They are schematic diagrams of different viewing angles of the chip pressing head of the utility model applied to thermal compression bonding;

[0016] Figure 3 It is a three-dimensional schematic diagram of the patch pressing head of the utility model;

[0017] Figure 4 It is a cross-sectional schematic diagram of the patch pressing head of the utility model;

[0018] Figure 5-7 They are three-dimensional schematic diagrams of the fixture of the present invention from different viewing angles. DETAILED DESCRIPTION

[0019] The utility model discloses a patch pressure head which can quickly raise and lower the temperature. Figure 3-Figure 4As shown, it mainly includes a Z-axis lifting mechanism, a U-axis rotation mechanism 10 arranged on the Z-axis lifting mechanism, a pressure sensor 11 connected to the lower end of the U-axis rotation mechanism 10, a pulse heating head 12 arranged at the lower end of the pressure sensor 11, and a fixture 13 for adsorbing the chip adsorbed on the lower end of the pulse heating head 12. The pulse heating head is designed with a rapid cooling channel for passing a cooling medium and two vacuum air ducts for vacuum adsorbing the fixture and the chip (not shown in the figure). By passing a cooling medium such as compressed gas, the heated pulse heating head 12 can be quickly cooled, which helps to avoid solidification during the dipping process before the next chip is heat-sealed. The vacuum air duct can adsorb the fixture and the chip through an external vacuum device.

[0020] Please combine Figure 5-7 As shown, the jig 13 includes a connecting plate 131 and a pressing head 132 that matches the chip specifications and is arranged at the lower end of the connecting plate 131. An I-shaped air groove 133 is provided on the connecting plate 131. An adsorption hole 134 that is connected to the air groove 133 is provided on the pressing head 132. One air passage of the pulse heating head 12 is connected to the vacuum suction holes distributed on the end surface of the pulse heating head 12 to adsorb the upper surface of the connecting plate 131, so as to quickly adsorb or replace different jigs 13, and the other air passage is connected to the air groove 133 and the adsorption hole 134 to quickly adsorb the chip on the lower surface of the pressing head 132.

[0021] The Z-axis lifting mechanism specifically includes a motor support seat 161, a Z-axis screw motor 15 disposed on the motor support seat 161, and a fixing frame 16 matched with a screw 151 of the Z-axis screw motor 15 through a nut 17. The U-axis rotation mechanism 10 is fixed on the fixing frame 16. The forward and reverse rotation of the Z-axis screw motor 15 can drive the nut 17 and drive the fixing frame 16, the pressure sensor 11, the pulse heating head 12, the fixture 13 and the chip thereon to be pressed down or raised together.

[0022] The Z-axis lifting mechanism also includes a lifting guide mechanism, which includes a pair of sliders 18 arranged on both sides of the fixed frame 16 and a pair of slide rails 19 respectively arranged to cooperate with the sliders. The upper end of the slide rail 19 can be connected and fixed to the lower end of the motor support seat 161, playing a guiding role in the lifting process.

[0023] In addition, the chip pressing head 3 can be used in the actual application of the thermal compression bonding equipment. Figure 1 , Figure 2 As shown, by arranging a gantry 14 on the frame 1, and arranging the motor support seat 161 of the Z-axis lifting mechanism on the gantry 14, a corresponding substrate support platform mechanism 2 is arranged below the patch pressing head of the utility model.

[0024] When in use, the chip is adsorbed on the fixture 13 by vacuum adsorption, and the U-axis rotation mechanism 10 is used to rotate and adjust the angle of the chip so that the chip is aligned with the substrate on the substrate support platform mechanism 2. The chip pressure head mechanism 3 controls the Z-axis lifting and pressing. At the same time, the pulse heating head 12 can quickly heat the chip pressed on the substrate for hot pressing bonding. The temperature control of fast heating can be raised to 250°C within 2 seconds, and the pressure sensor 11 of piezoelectric measurement technology can monitor the pressing process to avoid damage to the chip and substrate caused by overpressure, and defects such as cold soldering and bridging caused by insufficient pressure. After the hot pressing bonding is completed, the heating is stopped and the pressure head is quickly cooled by passing cooling gas, etc. The temperature of the fast cooling can be controlled to drop to 50°C within 1 second, so that the next chip can be extracted, dipped in glue, and hot pressed.

[0025] However, those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, any changes or modifications to the above embodiments will fall within the scope of the claims of the present invention.

Claims

1. A patch pressure head with rapid temperature rise and fall, characterized in that: It includes a Z-axis lifting mechanism, a U-axis rotation mechanism arranged on the Z-axis lifting mechanism, a pressure sensor connected to the lower end of the U-axis rotation mechanism, a pulse heating head arranged at the lower end of the pressure sensor, and a fixture adsorbed on the lower end of the pulse heating head for adsorbing chips. The pulse heating head is provided with a rapid cooling channel for passing a cooling medium and an airway for vacuuming the fixture and chips.

2. A patch pressure head with rapid temperature rise and fall according to claim 1, characterized in that: The Z-axis lifting mechanism comprises a motor support seat, a Z-axis screw motor arranged on the motor support seat, and a fixing frame matched with the screw of the Z-axis screw motor through a nut, and the U-axis rotation mechanism is fixed on the fixing frame.

3. A patch pressure head with rapid temperature rise and fall according to claim 2, characterized in that: The Z-axis lifting mechanism also includes a lifting guide mechanism, which includes a pair of sliders arranged on both sides of the fixed frame and a pair of slide rails respectively arranged to cooperate with the sliders, and the slide rails are connected and fixed to the motor support seat.

4. A patch pressure head with rapid temperature rise and fall according to claim 1, characterized in that: It also includes a gantry, and the Z-axis lifting mechanism is arranged on the gantry.

5. The patch pressure head with rapid temperature rise and fall according to claim 1, characterized in that: The fixture includes a connecting plate and a pressure head arranged at the lower end of the connecting plate and matching the chip specifications. The connecting plate is provided with an I-shaped air groove, and the pressure head is provided with an adsorption hole connected to the air groove. Two vacuum air ducts are provided in the pulse heating head, one of which is connected to the vacuum suction holes distributed on the end face of the pulse heating head to adsorb the upper surface of the connecting plate, and the other is connected to the air groove and the adsorption hole.

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