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CN-116525465-B - Grain transfer method for preventing bubble from being enclosed

CN116525465BCN 116525465 BCN116525465 BCN 116525465BCN-116525465-B

Abstract

The invention provides a grain transferring method for preventing air bubbles from being wrapped, which comprises the following steps that an adsorption device adsorbs grains by means of first negative pressure, the grains are bent, a die fixing device blows the grain placing area by means of positive pressure, the grain placing area bulges upwards, the center of the grain placing area is contacted with the center of the grains, gaps are formed between the periphery of the grain placing area and the periphery of the grains, the adsorption device stops adsorbing the grains by means of the first negative pressure, the grains are restored to be flat and are separated from the adsorption device, the die fixing device stops blowing the grain placing area by means of positive pressure, the grain placing area is restored to be flat, and the grains and the grain placing area extrude air in the gaps outwards, so that the gaps are closed, and the bottom surfaces of the grains are tightly attached to the top surfaces of the grain placing area. Therefore, the invention can achieve the effect of preventing the crystal grains and the crystal grain placement area from wrapping bubbles.

Inventors

  • LU YANHAO

Assignees

  • 梭特科技股份有限公司

Dates

Publication Date
20260505
Application Date
20220121

Claims (10)

  1. 1. A method of preventing bubble-encapsulated grain transfer, comprising: (a) An adsorption device adsorbs a die by a first negative pressure and moves to the upper part of a die placement area of a film, and the die is inwards sunken to bend; (b) A die bonding device for forming a gap between the periphery of the die placement area and the periphery of the die by blowing the die placement area with a positive pressure so that the die placement area bulges upward and the center of the die placement area contacts the center of the die, and (C) The adsorption device stops adsorbing the crystal grain by the first negative pressure to enable the crystal grain to be restored to be flat and separate from the adsorption device, meanwhile, the die fixing device stops blowing the crystal grain placement area by the positive pressure to enable the crystal grain placement area to be restored to be flat, in the process that the crystal grain and the crystal grain placement area synchronously restore to be flat, the crystal grain and the crystal grain placement area jointly extrude air in the gap outwards to enable the gap to be closed, and after the gap is completely closed, the bottom surface of the crystal grain is closely attached to the top surface of the crystal grain placement area.
  2. 2. The method of claim 1, wherein in the step (b), the curvature of the die placement area is larger than the curvature of the die.
  3. 3. The method of claim 1, wherein in the step (b), the positive pressure blows the stress balance of the die placement area in a state where the pressure of the positive pressure is averaged, so that the die placement area bulges upward.
  4. 4. The die transfer method for preventing air bubbles from being trapped in a die attach apparatus according to claim 1, wherein in the step (b), the pressure of the positive pressure is increased as the die attach apparatus is moved closer to the center of the die attach apparatus, so that the degree of bulge of the die attach area is gradually increased from the periphery to the center of the die attach area.
  5. 5. The method of claim 1, wherein the adsorption device comprises a fixing base and a suction nozzle, the fixing base is provided with a first vacuum channel, the first vacuum channel is connected with a vacuum device, the suction nozzle is arranged at the bottom of the fixing base and is provided with a second vacuum channel and a groove, the second vacuum channel is communicated with the first vacuum channel, and the groove is communicated with the second vacuum channel; Wherein in the step (a), the vacuum apparatus pumps the first vacuum channel, the gas in the groove sequentially passes through the second vacuum channel and the first vacuum channel to generate vacuum and provide the first negative pressure, the first negative pressure adsorbs the die through the groove, so that the die is concaved inwards to bend and sink into the groove, and wherein in the step (c), the vacuum apparatus stops pumping the first vacuum channel, the second vacuum channel and the groove no longer generate vacuum, the vacuum apparatus no longer provides the first negative pressure, and thus the suction nozzle stops adsorbing the die by the first negative pressure.
  6. 6. The method of claim 1, wherein the die bonding apparatus is provided with a first air pressure channel, the first air pressure channel is located in the middle of the die bonding apparatus and is connected with an air supply device, wherein in the step (b), the air supply device supplies air to the first air pressure channel to generate air flow and provide the positive pressure, the positive pressure blows the die placement area through the first air pressure channel, and wherein in the step (c), the air supply device stops supplying air to the first air pressure channel, the air flow is not generated any more by the first air pressure channel, the air supply device no longer provides positive pressure, and the die bonding apparatus stops blowing the die placement area by the positive pressure.
  7. 7. The method of claim 6, wherein a ring divides the first air pressure channel into a first chamber and a second chamber, a through hole is formed in the middle of the ring, the through hole is connected between the first chamber and the second chamber, and the diameter of the through hole is smaller than the diameters of the first chamber and the second chamber.
  8. 8. The method of claim 6, wherein the first air pressure channel has a width equal to a width of the die placement area.
  9. 9. The method according to claim 1, wherein in the step (b), the die bonding device adsorbs the outside of the die placement area by a second negative pressure, the adsorption device moves toward the die placement area, and wherein in the step (c), the adsorption device moves so that the adsorption device is away from the die, while the die bonding device stops adsorbing the outside of the die placement area by the second negative pressure.
  10. 10. The method of claim 9, wherein the die bonding apparatus is provided with a plurality of second air pressure channels, the plurality of second air pressure channels being disposed at intervals along a circumferential direction and being connected to a vacuum apparatus, wherein in the step (b), the vacuum apparatus pumps the plurality of second air pressure channels to generate vacuum and provide the second negative pressure, the second negative pressure adsorbs the outside of the die placement region through the plurality of second air pressure channels, and wherein in the step (c), the vacuum apparatus stops pumping the plurality of second air pressure channels, the plurality of second air pressure channels no longer generate vacuum, and the vacuum apparatus no longer provides the second negative pressure, whereby the die bonding apparatus stops adsorbing the outside of the die placement region through the second negative pressure.

Description

Grain transfer method for preventing bubble from being enclosed Technical Field The present invention relates to a method for transferring crystal grains, and more particularly, to a method for transferring crystal grains, which prevents air bubbles from being trapped. Background Integrated circuits are fabricated on semiconductor wafers in a batch-wise fashion through a number of processes, the wafer being further divided into a plurality of dies. In other words, the die is a small integrated circuit body fabricated from semiconductor material without packaging. Fig. 1 is a schematic diagram of step S10 of a conventional die transfer method, fig. 2 is a schematic diagram of step S20 of a conventional die transfer method, and fig. 3 is a schematic diagram of step S30 of a conventional die transfer method. In step S10, as shown in fig. 1, the divided dies 120 are orderly attached to a carrier film 110, an outer pushing member 141 of a pushing device 140 abuts against the bottom surface of the carrier film 110, and an inner pushing member 142 of the pushing device 140 pushes a target block 111 of the carrier film 110, so that the target block 111 bulges upward, and the dies 20 on the target block 111 contact a suction nozzle 132 of a suction device 130. In step S20, as shown in fig. 2, a vacuum device (not shown) pumps a first vacuum channel (not shown) of a fixing base 131 of the suction device 130, and the gas in a groove 1322 of the suction nozzle 132 sequentially passes through a second vacuum channel 1321 of the suction nozzle 132 and the first vacuum channel of the fixing base 131 to generate vacuum and provide a first negative pressure 161, and the first negative pressure 161 sucks the die 20 through the groove 1322. In step S30, as shown in fig. 3, the vacuum device stops evacuating the first vacuum channel, the second vacuum channel 1321 and the recess 1322 no longer generate vacuum, the vacuum device no longer provides the first negative pressure 161, and thus the suction nozzle 132 stops sucking the die 120 by the first negative pressure 161, and finally the die 120 is placed on a die placement area 151 of a film 150. However, as shown in fig. 2, when the suction nozzle 132 sucks the die 120 having a large size (size is greater than 5×5 mm) or the thin die 120 (size is less than 200 μm), since the area of the groove 1322 is relatively large, the suction area of the first negative pressure 161 is relatively large, and the die 120 is concaved inward to be bent and sunk into the groove 1322 when the first negative pressure 161 sucks the die 120 through the groove 1322. Therefore, as shown in fig. 3, after the die 120 is placed in the die placement area 151, the bottom surface of the curved die 120 and the top surface of the flat die placement area 151 together encapsulate the air bubbles to form a cavity 91 (void), which results in the die 120 not being thoroughly and tightly adhered to the die placement area 151, so that the subsequent processing procedure for picking or identifying the die 120 is easily affected by the air bubbles, and the yield of the product manufactured by the subsequent processing is reduced. Fig. 4 shows a schematic diagram of a conventional flat suction nozzle 132A sucking a die 120 with a flat surface. The conventional full-plane suction nozzle 132A has only the second vacuum passage 1321, and has no recess 1322, so that the bottom surface thereof is relatively flat. Therefore, the conventional full-plane suction nozzle 132A can suck the die 120 through the second vacuum through hole 1321 by the first negative pressure 161. Since the aperture of the second vacuum through-hole 1321 is relatively small, the suction area of the first negative pressure 161 is relatively small, and the die 120 is not concaved inward to be bent when the first negative pressure 161 sucks the die 120 through the second vacuum through-hole 1321, so that the die 120 can be kept flat. After the die 120 is placed in the die placement area 151, the bottom surface of the flat die 120 is thoroughly and tightly attached to the top surface of the flat die placement area 151, so that bubbles are not enclosed together, and no cavity 91 is formed, so that the subsequent processing procedure of picking or identifying the die 120 is not affected by the bubbles, and the product yield of subsequent processing is improved. Fig. 5 shows a schematic diagram of a conventional full-plane suction nozzle 132A sucking a die 120A with uneven surface. In some cases, the surface of the die 120A is uneven, such as particles adhering to the surface of the die 120A, or the die 120A is provided with copper pillars (bumps) or pads (pads), resulting in a gap 190 between the top surface of the die 120A and the bottom surface of the conventional full-plane suction nozzle 132A. Since the gap 190 is connected between the second vacuum path 1321 and the external space, the second vacuum path 1321 cannot generate vacuum, so that the conve