Method and device for picking up and placing ultrathin substrate chip

Abstract

The invention discloses a method and a device for picking and placing an ultrathin substrate chip, aiming at the ultrathin chip with the thickness of several microns, a volatile alcohol solution is dipped on the surface of a tip object, and the holding force in the chip picking process is provided by utilizing the principle of liquid surface tension; a tip object holding the chip through surface tension is controlled under a microscope, the tip object is close to the surface of a carrier needing to be placed, and the tension effect between the bottom of the chip and the carrier is provided through rapid spreading of the solution on the surface of the carrier; slowly lifting the tip object to realize that the ultrathin substrate chip is placed on the surface of the carrier; and finally, slowly heating to mildly dry volatile alcohols on the surface of the chip and between the bottom of the chip and the carrier so as to form effective chip placement. According to the method, mechanical damage to the ultrathin chip with only several micrometers in the mechanical picking and placing process can be avoided, and a feasible method is provided for effective placement of effective positions of the ultrathin substrate chip and the packaging carrier.

Description

Technical Field

[0001] The invention relates to a method and a device for picking up an ultra-thin substrate chip, and in particular to a method and a device for picking up and placing an ultra-thin substrate chip. Background Art

[0002] In the field of microwave and terahertz circuits, in order to reduce the parasitic losses caused by the substrate, it is often necessary to reduce the substrate of the chip to tens of microns or even less than ten microns. In the case of this chip thickness, after the chip is diced on the surface of the wafer, it can no longer be removed from the expanded wafer adhesive film surface using an automatic picker using the usual technical method. For such ultra-thin substrate chips, since the substrate of this type of chip only retains a few microns, its mechanical strength is not enough to support the chip in the vacuum suction nozzle suction operation, and it is very easy to find chip breakage, causing the vacuum suction nozzle to be blocked and increase the overall cost. Therefore, for this type of ultra-thin substrate chip, it is necessary to find a technical method that has lower mechanical strength for the chip during the pick-up and placement process and is conducive to actual operation. Summary of the invention

[0003] Purpose of the invention: In view of the above problems, the present invention proposes a method and device for picking up and placing ultra-thin substrate chips, which avoids the mechanical damage to the ultra-thin substrate chips caused by using a machine vacuum suction head or manual chip picking during traditional chip picking and placement, and improves the chip processing yield.

[0004] Technical solution: The technical solution adopted by the present invention is a method for picking up and placing ultra-thin substrate chips, comprising the following steps:

[0005] (1) placing a temporary support base on which the ultra-thin substrate chip is split upside down into a temporary support material removal tank, wherein the temporary support material removal tank contains a temporary support material removal solution, and the ultra-thin substrate chip sinks to the surface of the carrier located at the bottom of the temporary support material removal tank;

[0006] (2) lifting the carrier with the ultra-thin substrate chip on its surface from the solution, and drying the temporary support material remaining on the carrier and the chip surface to remove the solution;

[0007] (3) using the tip structure to dip into an alcohol solution, the amount of alcohol solution dipped into the tip structure ensures the formation of droplets, and the droplets cover the entire end of the tip structure without dripping; moving the tip structure to a carrier carrying an ultra-thin substrate chip, operating the tip structure to slowly approach the ultra-thin substrate chip to be picked up under a microscope, and picking up the chip by contacting the ultra-thin substrate chip with the droplet at the end of the tip structure;

[0008] (4) removing the carrier, moving the chip placement carrier under the ultra-thin substrate chip, and slowly bringing the tip structure with the chip picked up close to the surface of the chip placement carrier under a microscope until the alcohol solution is observed to spread on the surface of the chip placement carrier, and then slowly lifting the tip structure to leave the ultra-thin substrate chip attached to the surface of the chip placement carrier;

[0009] (5) Drying the alcohol solution on the ultra-thin substrate chip to achieve placement of the ultra-thin substrate chip.

[0010] The tip structure is a probe whose end diameter is in the range of 0.5 to 1 times the size of the ultra-thin chip.

[0011] As a preferred solution of the method for picking up and placing ultra-thin substrate chips described in the present invention, the temporary support material removal solution is a toluene solution or an environmentally friendly cleaning agent.

[0012] As a preferred solution of the method for picking up and placing ultra-thin substrate chips described in the present invention, the carrier is made of dust-free paper or filter paper.

[0013] As a preferred solution of the method for picking up and placing ultra-thin substrate chips described in the present invention, the alcohol solution is anhydrous ethanol or isopropanol.

[0014] As a preferred embodiment of the method for picking up and placing ultra-thin substrate chips described in the present invention, the drying process in step (2) adopts: drying temperature 40-50°C, drying time 1-2 hours; the drying process in step (5) adopts: drying temperature 40-45°C, drying time 0.5-1 hour.

[0015] As a preferred embodiment of the method for picking up and placing ultra-thin substrate chips described in the present invention, before moving the chip placement carrier in step (4), the chip placement carrier is pretreated, and the pretreatment adopts gas plasma cleaning, and the gas adopts pure argon or oxygen, and the cleaning time is 4-5 minutes.

[0016] The present invention provides a device for picking up and placing ultra-thin substrate chips, comprising: a temporary support material removal tank, an operating arm, a pick-up liquid dipping tank, a microscope, a chip placement carrier fixture and a heating plate;

[0017] The temporary support material removal tank comprises a reaction tank, a carrier and a carrier lifting device; the reaction tank is filled with a temporary support material removal solution for removing the temporary support material; the carrier is movably placed at the bottom of the container and is used to carry the ultra-thin substrate chip after the temporary support material is removed; the carrier lifting device is used to lift the carrier from the bottom of the container;

[0018] The operating arm comprises a moving structure and a tip structure, and the moving structure is controlled to move by an operating handle;

[0019] The pickup liquid dipping tank is arranged below the initial position of the operating arm, and contains an alcohol solution;

[0020] The microscope comprises a plurality of microscope lenses of different magnifications;

[0021] The chip placement carrier fixture is used to clamp the chip placement carrier;

[0022] The heating plate is used for drying the carrier, the chip placement carrier and the ultra-thin substrate chip.

[0023] The tip structure includes a probe whose end diameter is in the range of 0.5 to 1 times the size of the ultra-thin chip, and the probe is connected to the moving structure through a base.

[0024] As a preferred solution of the device for picking up and placing ultra-thin substrate chips described in the present invention, the device also includes a display module for converting the image collected by the microscope lens to be displayed on a display.

[0025] Beneficial effects: Compared with the prior art, the present invention has the following advantages: This method adopts a method for picking up and placing ultra-thin substrate chips using liquid surface tension, cleverly using the tension of alcohol liquid as a picking force on the carrier surface to achieve chip picking, and in the placement process, the alcohol liquid tension is used again to adsorb the ultra-thin substrate chip on the chip placement carrier, and the residual alcohol liquid is dried to achieve the placement of the ultra-thin substrate chip. The whole process is simple and easy to operate, which greatly improves the chip processing yield. This method can avoid mechanical damage to ultra-thin chips of only a few microns during mechanical picking and placement, and provides a feasible method for the effective placement of ultra-thin substrate chips and packaging carriers. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a flow chart of the method for picking up and placing ultra-thin substrate chips according to the present invention;

[0027] Figure 2 A schematic diagram of a segmented ultra-thin substrate chip on a temporary supporting substrate surface;

[0028] Figure 3 Schematic diagram of ultra-thin substrate chip separation;

[0029] Figure 4 It is a schematic diagram of the tip structure having an alcohol solution device contacting and picking up an ultra-thin substrate chip;

[0030] Figure 5 Schematic diagram of an ultra-thin substrate chip placed on a carrier surface and dried;

[0031] Figure 6It is a module diagram of the ultra-thin substrate chip picking and placing device of the present invention;

[0032] Description of the drawings: 1 is a temporary supporting base, 2 is an ultra-thin substrate chip, 3 is a dewaxing agent solution, 4 is a filter paper, 5 is a probe, 6 is an ethanol solution, and 7 is a tube shell. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0034] Example 1

[0035] The method for picking up and placing ultra-thin substrate chips of the present invention is shown in the flowchart as follows: Figure 1 As shown, the following steps are included:

[0036] (1) The chips separated into ultra-thin chips are placed on the temporary support substrate surface, such as Figure 2 As shown, the ultra-thin substrate chip is placed in Remover 2112 wax remover and soaked for 24 hours to remove and separate the wax remover used for temporary bonding between the ultra-thin substrate chip and the temporary support base. The separated ultra-thin substrate chip will sink to the filter paper pre-laid at the bottom of the container due to gravity;

[0037] (2) Pick up the filter paper with the ultra-thin substrate chip on the bottom surface of the container from bottom to top, ensuring that the chip on the surface does not fall off during the picking process;

[0038] (3) Place the removed filter paper on a hot plate at 45°C and bake for 2 hours to completely evaporate the Remover 2112 solvent remaining on the filter paper and the ultra-thin substrate chip, and then cool to room temperature. Figure 3 As shown;

[0039] (4) Place the dried filter paper carrying the ultra-thin substrate chip under a microscope, and adjust the magnification of the microscope so that the ultra-thin substrate chip on the surface of the filter paper can be observed at a farther focal length. Take another carrier with a pointed tip, such as a pointed probe, and ensure that the size of the tip is close to the size of the ultra-thin substrate chip. After dipping the tip of the probe in a small amount of ethanol solution, manually place it under the microscope and slowly contact the single ultra-thin substrate chip to be picked up on the surface of the filter paper. Due to the tension of the ethanol solution at the tip of the probe, the ethanol solution will quickly cover the surface of the chip, thereby achieving a picking force between the tip of the probe and the surface of the chip, such as Figure 4 As shown;

[0040] (5) The carrier where the chip is to be placed is first cleaned with pure argon plasma at a power of 100 W for 4 minutes to increase the activation degree of the carrier surface and improve the liquid wettability. The pretreated carrier is also placed under a microscope, and the probe with the ultra-thin chip picked up by the ethanol liquid in the previous step is slowly moved to the position on the carrier surface to be placed, and the chip is slowly put down until the chip is observed to be in contact with the substrate under the microscope, and the ethanol solution wrapped in the chip is spread on the contacting carrier surface under the action of tension; after observing the phenomenon in the previous step, the probe tip is slowly lifted artificially to break the liquid adhesion between the tip-ethanol-chip, so that the chip is attached to the carrier surface under the action of the surface tension of the ethanol solution;

[0041] (6) Place the carrier with the ultra-thin substrate chip attached in the previous step on a hot plate at 40° C. and bake for 30 minutes to evaporate the ethanol solution on the surface and bottom of the chip in contact with the carrier, and finally form a placement contact between the chip and the carrier surface. Figure 5 As shown, preparation is completed for the subsequent further processes.

[0042] Example 2

[0043] The device for picking up and placing ultra-thin substrate chips of the present invention has a structural schematic diagram as shown in FIG. Figure 6 As shown, it includes: a temporary support material removal tank, a manipulation arm, a pick-up liquid dipping tank, a microscope, a chip placement carrier fixture and a heating plate;

[0044] Among them, the temporary support material removal tank includes a reaction tank, a carrier and a carrier lifting device; the reaction tank is filled with a temporary support material removal solution for removing the temporary support material; the carrier is movably placed at the bottom of the container for carrying the ultra-thin substrate chip after the temporary support material is removed; the carrier lifting device is used to lift the carrier from the bottom of the container. The operating arm includes a moving structure and a tip structure, and the movement of the moving structure is controlled by an operating handle. The pickup liquid dipping tank is arranged below the initial position of the operating arm, and the tank is filled with an alcohol solution. The microscope includes a plurality of microscope lenses of different magnifications for magnifying the field of view to move the operating arm to the desired position. The chip placement carrier fixture is used to clamp the chip placement carrier, and the chip placement carrier is a structure for placing the ultra-thin substrate chip picked up by the tip structure. The chip placement carrier can be an external rack carrier structure. The heating plate is used to dry the carrier, the chip placement carrier and the ultra-thin substrate chip.

[0045] The tip structure includes a probe whose end diameter is in the range of 0.5 to 1 times the size of the ultra-thin chip, and the probe is connected to the moving structure through a base.

[0046] The device also includes a display module, which is used to convert the image collected by the microscope lens to a display for display.

Claims

1. A method for picking up and placing ultra-thin substrate chips, characterized in that: The following steps are involved: (1) placing a temporary support base on the surface of which the ultra-thin substrate chip has been split upside down into a temporary support material removal tank, wherein the temporary support material removal tank contains a temporary support material removal solution, and the ultra-thin substrate chip sinks to the surface of the carrier located at the bottom of the temporary support material removal tank; (2) lifting the carrier with the ultra-thin substrate chip on its surface from the solution, and drying the temporary support material remaining on the carrier and the chip surface to remove the solution; (3) using the tip structure to dip the alcohol solution, the amount of alcohol solution dipped by the tip structure ensures that a droplet is formed, and the droplet covers the entire end of the tip structure without dripping; Move the tip structure to the carrier carrying the ultra-thin substrate chip, operate the tip structure to slowly approach the ultra-thin substrate chip to be picked up under a microscope, and pick up the chip by contacting the ultra-thin substrate chip with the droplet at the end of the tip structure; (4) removing the carrier, moving the chip placement carrier under the ultra-thin substrate chip, and slowly bringing the tip structure with the chip picked up close to the surface of the chip placement carrier under a microscope until the alcohol solution is observed to spread on the surface of the chip placement carrier, and then slowly lifting the tip structure to leave the ultra-thin substrate chip attached to the surface of the chip placement carrier; (5) Drying the alcohol solution on the ultra-thin substrate chip to achieve placement of the ultra-thin substrate chip.

2. The method for picking up and placing ultra-thin substrate chips according to claim 1, characterized in that: The temporary support material removal solution is a toluene solution or an environmentally friendly cleaning agent.

3. The method for picking up and placing ultra-thin substrate chips according to claim 1, characterized in that: The carrier is made of dust-free paper or filter paper.

4. The method for picking up and placing ultra-thin substrate chips according to claim 1, characterized in that: The tip structure is a probe whose end diameter is in the range of 0.5 to 1 times the size of the ultra-thin chip.

5. The method for picking up and placing ultra-thin substrate chips according to claim 1, characterized in that: The alcohol solution is anhydrous ethanol or isopropanol.

6. The method for picking up and placing ultra-thin substrate chips according to claim 1, characterized in that: The drying process in step (2) adopts: drying temperature 40-50°C, drying time 1-2 hours; the drying process in step (5) adopts: drying temperature 40-45°C, drying time 0.5-1 hour.

7. The method for picking up and placing ultra-thin substrate chips according to claim 1, characterized in that: Before moving the chip placement carrier in step (4), the chip placement carrier is pretreated, and the pretreatment adopts gas plasma cleaning, the gas adopts pure argon or oxygen, and the cleaning time is 4-5 minutes.

8. An ultra-thin substrate chip pick-up and placement device, characterized in that: include: Temporary support material removal tank, manipulator arm, pick-up fluid dip tank, microscope, chip placement carrier fixture and heating plate; The temporary support material removal tank comprises a reaction tank, a carrier and a carrier lifting device; the reaction tank is filled with a temporary support material removal solution for removing the temporary support material; the carrier is movably placed at the bottom of the container and is used to carry the ultra-thin substrate chip after the temporary support material is removed; the carrier lifting device is used to lift the carrier from the bottom of the container; The operating arm comprises a moving structure and a tip structure, and the moving structure is controlled to move by an operating handle; The pickup liquid dipping tank is arranged below the initial position of the operating arm, and contains an alcohol solution; The microscope comprises a plurality of microscope lenses of different magnifications; The chip placement carrier fixture is used to clamp the chip placement carrier; The heating plate is used for drying the carrier, the chip placement carrier and the ultra-thin substrate chip.

9. The device for picking up and placing ultra-thin substrate chips according to claim 8, characterized in that: The tip structure comprises a probe whose end diameter is in the range of 0.5 to 1 times the size of the ultra-thin chip, and the probe is connected to the moving structure through a base.

10. The device for picking up and placing ultra-thin substrate chips according to claim 8, characterized in that: The device also includes a display module, which is used to convert the image collected by the microscope lens to a display for display.

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