JP2007242662A - Microchip peeling method and peeling apparatus, and method of selecting and transferring microchip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microchip peeling method and a peeling apparatus thereof which effectively and highly accurately can pick up the required number of microchips, in a short time. <P>SOLUTION: Microchips 4 are peeled from among a group of microchips 4 stuck on an expansion sheet 3. The microchips 4 on the expansion sheet 3 are selectively supported by a plurality of fixed protrusions (push-up pins 14) arranged with a predetermined interval corresponding to the microchips 4 to be peeled, and the expansion sheet 3 is vacuum-sucked by vacuum-sucking holes 15, each being provided near respective push-up pins 14. In this way, only the microchip 4 desired to be selectively picked up from the densely provided microchip 4 in the group can exactly pop up in the upper part in the vertical direction from among the other microchips 4, while maintaining its horizontal positional direction. In this state, the plurality of microchips 4 selected by using a chip holding mechanism (e.g. a thermally peeling sheet 17 or a vacuum pickup 30) are peeled from the expansion sheet 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a microchip peeling method and a peeling apparatus applied when transferring a microchip (for example, a pixel control element) to a flat display substrate such as a liquid crystal display or an organic EL display with an increased interval. Furthermore, the present invention relates to a method for selective transfer of a microchip using this.

  For example, in a flat display represented by a liquid crystal display or an organic EL display, a microelectronic device such as a thin film transistor (TFT) that directly drives each pixel using a chemical vapor deposition method (CVD method) on a glass substrate is directly used. To be formed. By controlling on / off, shading, etc. of each pixel with this microelectronic device, it is possible to display an image.

  In this type of flat display, there is a strong demand for a large screen, and accordingly, there is an urgent need to increase the substrate area. Naturally, it is necessary to increase the area of the glass substrate to be used in response to the increase in the screen size. In the conventional technique, a thin film transistor or the like as a driving element is provided on the increased glass area. It is necessary to form directly.

  However, if a thin film transistor or the like, which is a driving element, is directly formed on a glass substrate having an increased area, it is accompanied by various difficulties and causes a significant increase in manufacturing cost. Specifically, as the substrate area expands, it is necessary to inevitably increase the size of manufacturing equipment (CVD equipment, etc.) for producing microelectronic devices such as thin film transistors on a glass substrate, and the clean room in which they are installed. Need to be larger. As a result, a large capital investment is required, which leads to an increase in manufacturing costs.

  In addition, the method of directly forming a thin film transistor as a driving element on a glass substrate still has a problem in terms of the characteristics of the element (thin film transistor), which is a great obstacle to improving the display quality of a flat display. . In the above method, an amorphous silicon (a-Si) film that can be produced with a deposited thin film at a low temperature of about 300 ° C. that can withstand a glass substrate must be used as a semiconductor film. The operation performance is inferior. In order to solve this problem, for example, it has been studied to melt a deposited a-Si film by laser irradiation to form polycrystalline silicon (polysilicon), and to form a thin film transistor having a high mobility using this. In this case, high cost is required for the production of polycrystalline silicon by laser melting, and at present, the application range is limited to a flat display having a relatively small area.

  Under such circumstances, the inventors of the present application form a large screen flat display by forming electronic devices such as thin film transistors in a dense state on a wafer or the like, and mounting diced microchips at predetermined positions on a glass substrate. Has been proposed (see, for example, Patent Document 1 and Patent Document 2).

  In Patent Document 1, a large number of pixel control elements are formed at a pitch obtained by dividing the pitch of the flat display substrate by a natural number, and pixel control elements corresponding to the pitch of the flat display substrate are selectively picked up, and the flat display substrate is placed on the flat display substrate. A pixel control element transfer method is disclosed in which the pixel control element is held by plastic deformation of the formed transparent thermoplastic resin film, and the periphery of the pixel control element is fixed by a transparent ultraviolet curable resin film. A method of manufacturing a flat display substrate by applying this is disclosed.

  By the way, in the method of transferring the microchips such as the pixel control element with the interval increased, it is necessary to selectively peel and take out a plurality of microchips to be transferred from the group of cut microchips in a dense state. . In the inventions described in Patent Document 1 and Patent Document 2, a method of adsorbing a microchip (pixel control element) on an adhesive tape using a vacuum chuck is disclosed. It is necessary to locally reduce the adhesive strength of the adhesive tape, and if the adhesive strength of the adhesive tape is high, it is difficult to reliably peel off by a vacuum chuck. Thus, it is difficult to accurately position the vacuum chuck.

  As a method for reliably taking out a predetermined microchip from a dense group of microchips, the microchip group is placed on a so-called expansion sheet, the position of the microchip to be taken out is determined, and then a pin is inserted from the back side of the microchip. A method is known in which a microchip is pushed out to be separated from another microchip and taken out by a pickup. However, in this case, as the number of microchips to be taken out increases, the takeout time becomes longer. As a result, the expansion sheet remains unbalanced and gradually becomes difficult to reliably take out the microchips. Will occur. In order to ensure the removal of the microchip, it is advantageous to increase the push-up amount of the microchip. However, if the push-up amount of the microchip is increased, the deformation amount of the expansion sheet increases and the microchip is increased. There is also a contradiction that it becomes difficult to take out.

  In order to eliminate such inconvenience, the expansion sheet around the microchip to be taken out is sucked by the suction hole arranged concentrically with the microchip protruding pin, and an attempt to reduce the protruding amount of the pin (See, for example, Patent Document 3).

Patent Document 3 discloses a method in which chips arranged on an adhesive sheet are individually picked up using a vacuum suction collet, and a portion of the adhesive sheet corresponding to the periphery of the chip is lowered at the tip of a cylindrical needle sleeve. The tip is pushed up by a predetermined amount from the tip, and the tip corresponding to the tip of the adhesive sheet is pushed up by a predetermined amount at the tip of the needle that fits inside the needle sleeve. A chip pick-up method for picking up by vacuum suction is disclosed.
Japanese Patent No. 3474187 Japanese Patent No. 3492679 Japanese Patent Laid-Open No. 5-121525

  However, the method described in Patent Document 3 is a method of picking up microchips individually, and there is a major drawback that the apparatus configuration becomes complicated when it is applied to an application for taking out a large number of microchips at once. No such proposal has been made.

  As described above, for example, an effective method for selectively picking up a large number of microchips that are closely packed on a wafer ring at the same time and selectively picking up microchips that have been separated has not been developed. Even if it can be taken out one by one or a plurality of pieces can be taken out, about tens of pieces are the limit, and there is no certainty, and it takes a long time to work.

  The present invention has been proposed in view of the above-described conventional circumstances, and can efficiently project only microchips selected from a group of closely spaced microchips, and can damage the expansion tape. It is another object of the present invention to provide a microchip peeling method and a peeling device that can effectively and accurately take out a required number of microchips in a short time. It is another object of the present invention to provide a selective transfer method of a microchip that can manufacture a transfer substrate and a large area substrate with high accuracy in a short time using the microchip thus taken out.

  In order to achieve the above-described object, the microchip peeling method of the present invention is a microchip peeling method for selectively peeling a microchip from a group of microchips attached on an expansion sheet, and is to be peeled off. A plurality of fixing protrusions arranged at predetermined intervals corresponding to the microchips selectively support the microchips on the expansion sheet, and the expansion sheet is vacuumed by a vacuum suction hole provided in the vicinity of each fixing protrusion. In this state, a plurality of microchips selected by the chip holding mechanism are peeled off from the expansion sheet.

  Moreover, the microchip peeling apparatus of the present invention is a microchip peeling apparatus that selectively peels a microchip from a group of microchips attached on an expansion sheet, and corresponds to a microchip to be peeled. A chip peeling plate having a plurality of fixed protrusions arranged at intervals of each other, a vacuum suction hole provided in the vicinity of each fixed protrusion, and a plurality of microchips to be peeled together, and the expansion sheet A chip holding mechanism for peeling from the chip, and selectively supporting the microchip on the expansion sheet by the fixing protrusion of the chip peeling plate, and vacuum-sucking the expansion sheet near the fixing protrusion by the vacuum suction hole. Peeling a plurality of microchips selected by the chip holding mechanism in the state from the expansion sheet And features.

  In the present invention, a vacuum suction hole is provided around the fixed protrusion for separating the microchip, and the expansion chip is drawn together with the microchip placed on the vacuum suction hole, so that the microchip to be selectively taken out can be obtained. Separated at once. That is, the present invention is not based on the idea of selectively pushing up the microchips to be taken out, but has a feature that all the microchips that are not selected are pushed down, and the microchips to be taken out are relatively lifted and separated from other microchips. .

  The peeling method and peeling apparatus of the present invention having the above-described features can be said to be an epoch-making peeling method and peeling apparatus that can peel a microchip to be peeled with high accuracy and reliability while having a simple structure. For example, since the position of the selected microchip does not change before and after the separation, a stable removal of the microchip is realized. In addition, since the other microchips around the microchip to be taken out are forcibly pressed down uniformly, the protruding height of the fixed protrusion can be suppressed to a fraction of that of the conventional system. Therefore, excessive tension is not applied to the expansion sheet, and the deformation does not proceed even if the microchip removal operation is repeated, and the microchip removal accuracy does not deteriorate.

  According to the peeling method and the peeling apparatus of the present invention having the above-described configuration, it is possible to efficiently separate only the microchip selected from the dense microchip group, and without causing damage to the expansion tape, It is possible to take out the required number of microchips with high accuracy in a short time. Therefore, according to the microchip selective transfer method of the present invention to which this is applied, a large-area substrate in which microchips are spaced apart can be manufactured with high accuracy in a short time. Large-screen high-performance displays and large-area high-performance solar cell panels that were considered difficult to be manufactured can be manufactured at low cost and in large quantities.

  Hereinafter, embodiments of a microchip peeling method and peeling apparatus to which the present invention is applied, and a microchip selective transfer method will be described in detail with reference to the drawings.

(Microchip transfer process)
Prior to the description of the microchip peeling method and peeling apparatus of the present invention, first, a microchip transfer process (microchip selective transfer method) to which the microchip peeling method and peeling apparatus of the present invention are applied will be described. .

  FIG. 1 shows an outline of the microchip transfer process. In this microchip transfer process, an element (for example, a pixel control element) formed on a silicon wafer is cut and selectively removed, and finally arranged on a mother board (for example, a flat display substrate) at a predetermined interval. For example, a large-screen flat display is realized by transferring the image onto the screen.

  In the microchip transfer process, a microelectronic device such as a thin film transistor is formed on the silicon wafer 1 as shown in FIG. In the case of manufacturing a large screen flat display, a pixel control element is formed.

  Next, the silicon wafer 1 in which the microelectronic device is built is placed on the extension sheet 3 stretched on the wafer ring 2 with a predetermined tension, and as shown in FIG. 1B, it corresponds to each microelectronic device. Then, the microchips 4 are cut (diced), and the microchip groups are placed densely on the extension sheet 3. The shape of each microchip 4 is, for example, a 0.4 mm square, and the chip interval is, for example, 0.06 mm. The number of microchips 4 placed on the extension sheet 3 is, for example, 125 × 125, and the microchip area where the microchips 4 are arranged is 57.5 mm square.

  By selectively taking out a plurality of microchips 4 on the extension sheet 3, the interval between the microchips 4 is expanded. For example, if three microchips 4 are skipped and every four chips are sequentially taken out, the interval between the microchips 4 is increased to 1.84 mm. As shown in FIG. 1C, the microchips 4 that are selectively taken out are transferred, for example, in the form of being arranged on a selective take-out sheet 5. In this example, the interval between the microchips 4 on the selective take-out sheet 5 is 1.84 mm, the number of microchips 4 is 25 × 25, and the microchip area where the microchips 4 are arranged is 46 mm square. .

  The microchips 4 on the selective take-out sheet 5 are transferred onto a chip batch transfer substrate 6 as shown in FIG. Here, the microchips 4 on the four selective take-out sheets 5 are transferred onto the chip batch transfer substrate 6. The shape of the chip batch transfer substrate 6 is, for example, 125 mm square, and the material is, for example, stainless steel. An adhesive material layer is formed on the surface of the chip batch transfer substrate 6 on which the microchips 4 are placed, and the microchips 4 are held by an adhesive force.

  As shown in FIG. 1 (E), a plurality of chip batch transfer substrates 6 such as 16 × 9 are prepared, and as shown in FIG. 1 (F), each chip batch transfer substrate 6 is prepared. The upper microchip 4 is sequentially transferred onto the mother board 7. The shape of the mother board 7 is a rectangular shape of 1620 mm × 948 mm. By transferring the microchips 4 of the 16 × 9 chip batch transfer substrate 6, 800 × 450 microchips 4 are arranged in a matrix on the mother board 7. In the case of a flat display, the display area is 1472 mm × 828 mm, and a large screen display is realized. The advantage of this method is that the transfer state can be confirmed at the stage of the chip batch transfer substrate 6 and the final yield of the mother board 7 can be increased. When the transfer state of the microchips 4 is confirmed at the final stage of the mother board 7, if there is a transfer failure, the whole mother board 7 becomes NG. However, the stage of the chip batch transfer board 6 is determined. In this case, by removing the chip batch transfer substrate 6 in which the transfer failure has occurred, the occurrence of the failure at the stage of the mother board 7 can be minimized.

(First embodiment)
The microchip peeling method and peeling apparatus of the present invention are applied to selective removal of the microchip 4 on the extension sheet 3 in the microchip transfer process. Hereinafter, although the peeling method and peeling apparatus of the microchip of this embodiment are demonstrated, this embodiment is embodiment in the case of peeling a microchip with the heat peeling sheet which has an adhesive surface.

  FIG. 2A to FIG. 2F show the microchip peeling method of this embodiment in the order of steps. In this embodiment, in order to selectively take out the microchips 4 on the extension sheet 3, first, as shown in FIG. 2A, the extension sheet 3 is stretched and the microchips 4 are placed in a dense state. The wafer ring 2 is installed in the peeling device. Although the wafer ring 2 has a ring shape here, the wafer ring 2 is not necessarily limited to this, and may be, for example, a square frame.

  In the peeling apparatus, a porous adsorption plate 12 is fixed on a stainless steel base 11, and a chip peeling plate 13 is attached thereon. Further, a positioning device (not shown) for positioning the wafer ring 2 is attached on the base 11 so as to surround the chip peeling plate 13.

  The positioning device aligns the wafer ring 2 by, for example, pushing the wafer ring 2 inward from four peripheral directions. By installing the positioning device, for example, even if the arrangement pitch of the microchips 4 arranged on the wafer ring 2 is larger than the arrangement pitch of the push-up pins formed on the chip peeling plate 13 described later, This can be absorbed. This is because the wafer ring 2 is compressed by increasing the amount of the wafer ring 2 pushed from the periphery by the positioning device, and the arrangement pitch of the microchips 4 on the wafer ring 2 is also compressed. Therefore, even if there is a slight difference between the arrangement pitch of the microchips 4 on the wafer ring 2 and the arrangement pitch of the push-up pins formed on the chip peeling plate 13, it can be absorbed by preparing the positioning device. Can do.

  As described above, a large number of push-up pins 14 for selectively taking out the microchips 4 are formed on the chip release plate 13 as fixed protrusions. The push-up pins 14 are arranged so as to be directly below the microchips 4 to be selectively taken out of the microchips 4 arranged on the extension sheet 3 of the wafer ring 2, for example, the arranged microchips. When every four of the four are taken out, they are arranged at a pitch corresponding to this.

  A vacuum suction hole 15 is formed around the push-up pin 14 of the chip peeling plate 13. The vacuum suction holes 15 are for adsorbing the expansion sheet 3 for adhering and fixing the microchips 4. For example, as shown in FIG. 3, the vacuum suction holes 15 are provided at four locations around each push-up pin 14 and in the region between the push-up pins 14. Is formed.

  The porous adsorption plate 12 is used for performing vacuum suction in a vacuum suction hole 15 provided in the chip peeling plate 13, and is provided with a pipe 12a for vacuum suction and pressure air release. An air pressure control mechanism for controlling the vacuum suction and the pressure air release is connected to the pipe 12a. The porous adsorption plate 12 does not necessarily have to be a porous plate. For example, if the porous adsorption plate 12 has a function of supporting the chip peeling plate 13 and adsorbing the expansion sheet 3 through the vacuum suction holes 15, for example, a cutting plate is used. It may be a grooved plate or a plate having a through hole immediately below the vacuum suction hole 15. In this case, it is also possible to form the push-up pin 14 integrally with a plate for vacuum suction so as to be integrated with the chip peeling plate 13.

  FIG. 2B shows a mounting state of the wafer ring 2 on which the extension sheet 3 is stretched and the microchips 4 are placed in a dense state to the peeling device. When peeling and taking out the microchips 4, the wafer ring 2 on which the cut and separated microchips 4 are densely adhered and fixed to the expansion sheet 3 is placed on the chip peeling plate 13. At this time, the surface (lower side surface) opposite to the surface to which the microchip 4 of the expansion sheet 3 is adhesively fixed is slightly in contact with the peripheral portion of the chip peeling plate 13 where the push-up pin 14 is not formed. It is placed on the pedestal 16 that has been adjusted to a height. Then, the wafer ring 2 is aligned so that a push-up pin 14 for pushing up the microchip 4 is positioned directly below the microchip 4 to be selectively taken out. This alignment may be performed using the positioning device. For example, when the arrangement pitch of the microchips 4 on the wafer ring 2 is larger than the arrangement pitch of the push-up pins 14, the alignment device is adjusted (for example, Then, the alignment screw is rotated in the opposite phase), and the wafer ring 2 is compressed and adjusted so that the microchip 4 to be taken out matches the pitch of the push-up pins 14.

  In this state, when vacuum suction is started from the pipe 12 a of the porous adsorption plate 12, air is sucked through the vacuum suction holes 15 of the chip peeling plate 13 placed thereon, and between the expansion sheet 3 and the chip peeling plate 13. The pressure in the space gradually decreases, and the expansion sheet 3 is pressed against the chip peeling plate 13 at atmospheric pressure. Further, since the vacuum suction hole 15 is also formed around the push-up pin 14, the expansion sheet 3 is pushed down in the vertical direction even in the immediate vicinity of the push-up pin 154. Therefore, the height of the push-up pin 14 may be small, and may be as high as about 0.4 mm, for example.

  As a result, as shown in FIG. 2 (C), the microchip 4 directly above the push-up pin 14 is shaped to ride on the push-up pin 14 and stays at a higher position than the other microchips 4. become. The other microchips 4 are not supported by the push-up pins 14, and are attracted to the chip peeling plate 13 while being attached to the expansion sheet 3. At this time, the microchip 4 around the push-up pin 14 is not completely drawn to the chip peeling plate 13, but the chip is peeled off from the microchip 4 on the push-up pin 14 according to the inclined surface of the expansion sheet 3. It will be located downward toward the direction of the plate 13.

  As described above, only the microchips 4 that are desired to be selectively taken out from the dense microchip group are accurately projected vertically above the other microchips 4 while maintaining the horizontal position. Further, in the microchip 4 on the push-up pin 14, since the contact area with the expansion sheet 3 is also small, the adhesive force by the expansion sheet 3 is reduced, and it becomes easy to peel off.

  Then, next, the microchip 4 to be taken out selectively (peeled-out microchip 4) is peeled (taken out). In this embodiment, thermal peeling is used as a chip holding mechanism for peeling the microchip 4. Use a sheet.

  The heat release sheet 17 is attached to the transparent resin frame 18, and is placed on the microchip 4 that selectively protrudes with the adhesive surface 17a on the bottom, as shown in FIG. And as shown in FIG.2 (E), when the surface on the opposite side to the adhesion surface 17a of the heat | fever peeling sheet 17 is pressed with a member like a squeegee in order from the edge of the microchip 4 group which is going to peel off. The pressed surface 17 a of the pressed part of the heat release sheet 17 is pressed against the top surface of the microchip 4. Thereafter, when the squeegee passes, the thermal peeling sheet 17 tries to return to the original position with the tension (return tension), and accordingly, the microchips 4 to be taken out are peeled in order. The pressing method of the heat release sheet 17 is not limited to the squeegee, and may be performed, for example, by applying air pressure to the heat release sheet 17.

  At the time of peeling, the microchip 4 is peeled off due to the difference in the adhesive force between the microchip 4 and the expansion sheet 3 and the adhesive force between the microchip 4 and the thermal release sheet 17. Here, the adhesive force of the heat release sheet 17 is set to be smaller than the adhesive force of the expansion sheet 3 if the area is the same, but actually, the area of the upper end of the push-up pin 14 is set to the microchip 4. Since the contact area (effective adhesive force) between the microchip 4 and the expansion sheet 3 is reduced by the pushing-up by the push-up pin 14, the microchip 4 is surely attached to the thermal peeling sheet 17. Will be peeled to the side. FIG. 2F shows a transfer state to the heat release sheet 17.

  The selective removal of the microchip 4 by the thermal release sheet 17 corresponds to the selective removal shown in FIGS. 1B to 1C in the previous microchip transfer process. This corresponds to the selective take-out sheet 5. Therefore, if it is applied to the microchip transfer process, the microchip 4 taken out on the thermal release sheet 17 is then transferred to a chip batch transfer substrate.

  4A to 4E show a transfer process of the microchips 4 on the thermal release sheet 17 to the chip batch transfer substrate 20.

  As shown in FIG. 4A, the chip batch transfer substrate 20 includes a chip batch transfer back plate 21 having a fitting hole 21a for positioning with respect to the suction portion 23, and an adhesive material formed thereon. In the transfer, the chip batch transfer substrate 20 is set on the suction portion 23. The suction portion 23 is installed on the base plate 24, and a plurality of vacuum suction holes 23a are provided, and a vacuum suction pipe 23b is provided. In addition, fitting pins 23 c for positioning the chip batch transfer substrate 20 are planted and formed in the suction portion 23. Furthermore, the base plate 24 is equipped with a heater for peeling the microchips 4 from the heat peeling sheet 17.

  On the other hand, as shown in FIG. 4B, in order to adsorb the four thermal release sheets 17 in a state where the microchips 4 are selectively taken out and adhered to the chip batch transfer substrate 20. The vacuum pick-up 25 is equipped, and each vacuum pick-up 25 is connected to a pipe 25a for vacuum and pressure air, and further connected to a pneumatic control device.

  In order to transfer the microchip 4 from the thermal release sheet 17 to the chip batch transfer substrate 20, first, the thermal release sheet 17 is adsorbed and fixed to the vacuum pickup 25 as shown in FIG. At this time, fitting holes 25b are formed in the vacuum pickup 25 corresponding to the microchips 4 on the heat release sheet 17, and the microchips 4 on each heat release sheet 17 are fitted into these fitting holes 25b. As shown in the figure, they are positioned and fixed by suction.

  At the time of transfer, as shown in FIG. 4C, the heat release sheets 17 are sucked one by one by the vacuum pickup 25 and placed on a predetermined position of the chip batch transfer substrate 20 for adhesion. At this time, since the physical arrangement of the vacuum pick-up 25 for adsorbing and fixing the thermal release sheet 17 and the base plate 24 to which the chip batch transfer substrate 20 is attached is determined, the thermal release sheet 17 is picked up and transferred to the chip batch. The operation of pressing against the mounting substrate 20 may be performed simply by performing a control of parallel translation by a predetermined distance.

  Next, as shown in FIG. 4D, the heater of the base plate 24 is turned on to heat the thermal release sheet 17, and the microchips 4 are released from the thermal release sheet 17 so that the chip batch transfer substrate 20 is over. Transcript to. At the time of the transfer, in addition to the heating by the base substrate 24, hot air may be separately blown to the thermal peeling sheet 17 to promote thermal peeling.

  After the transfer, the chip batch transfer substrate 20 is removed from the suction unit 23, and the process proceeds to the transfer process of the microchips onto the mother board in the chip transfer process.

  As described above, in the microchip peeling method and the microchip peeling apparatus of the present embodiment, the vacuum suction hole 15 for vacuum suction is provided around the push-up pin 14 for chip separation, and the expansion sheet 3 is passed through the vacuum suction hole 15. Is pulled together with the microchip 4 thereon, and the microchip 4 to be selectively taken out is separated at once. That is, the idea is not to push up the microchips 4 to be selectively extracted, but to push down all the microchips 4 that are not selected, and to separate the microchips 4 to be selectively lifted up relative to each other. Therefore, it is possible to realize the removal of the microchip 4 having a simple structure and high accuracy and stability.

  In addition, the microchip peeling method and the microchip peeling apparatus of this embodiment have various advantages. For example, since the position of the microchip 4 to be selected does not change before and after separation, stable chip removal is possible. In addition, since the other microchips around the microchip 4 to be taken out are forcibly pressed down uniformly, the height of the ejector pin 14 can be reduced to a fraction of that of the conventional system (the system for pushing up the pin). Can do. Therefore, an excessive force is not applied to the expansion sheet 3 and the deformation does not proceed even if the chip extraction operation is repeated, so that the chip extraction accuracy does not deteriorate.

  Furthermore, it is particularly convenient when the arrangement of the transfer destination microchips 4 is the same as the taken-out pitch, that is, when a large number of microchips 4 are selectively extracted. Even when it is taken out, the advantages of the present invention come into play. For example, if a large number of microchips 4 once positioned are separated, then the microchips 4 separated by a pickup or the like may be taken out in order. After all the microchips 4 are taken out, if the operation of selectively separating another microchip group is repeated, the push-up operation of the microchips 4 is simplified, and the chip takeout time is shortened. The accuracy does not deteriorate.

  In the present embodiment, the thermal release sheet 17 is used as a chip holding mechanism for peeling the separated microchips 4. This is effective for taking out microchips. As the surface area of the microchip 4 becomes smaller, for example, in a method of holding the microchip 4 using vacuum suction, it becomes difficult to take out a large number of microchips 4 at the same time. This is because if there is even one microchip 4 that is not attracted in the correct posture, the suction of other microchips 4 is hindered by the influence of the microchip 4. This is also related to the fact that the suction force using vacuum pressure is relatively small compared to disturbances such as friction force, electrostatic suction force, or intermolecular attractive force. The removal method using the adhesive force of the thermal release sheet 17 is disadvantageous in that a subsequent thermal release operation is necessary and that the thermal release sheet 17 itself is a consumable item. This has a great advantage that the certainty of simultaneous removal of the chips 4 is high.

  In addition, although this embodiment demonstrated the case where a heat release sheet was used as a chip | tip holding | maintenance mechanism, instead of using this heat release sheet, an ultraviolet curable sheet (UV curable sheet) having an adhesive surface was used. Also good. In that case, in order to peel the microchip from the expansion sheet 3, ultraviolet rays are irradiated from the opposite side of the adhesive surface instead of heating.

(Second Embodiment)
In this embodiment, a vacuum pickup is used as a chip holding mechanism when taking out a microchip from an expansion sheet. FIGS. 5A to 5F show a selective chip peeling process. In this chip peeling process, the steps from FIG. 5A to FIG. 5C are the same as the steps from FIG. 2A to FIG. 2C of the first embodiment. Therefore, the same symbols are attached to the same members, and the description thereof is omitted here.

  When the microchip 4 is selectively peeled (taken out) by the vacuum pickup 30, after the microchip 4 to be selectively taken out is popped out as shown in FIG. 5C, as shown in FIG. 5 (D9). The vacuum pickup 30 is disposed on the microchip 4. The vacuum pickup 30 has a recess 31 for fitting each microchip 4 and a through hole 32 penetrating the bottom of the recess 31, and further, A pipe 33 for vacuum and pressure air is connected to an air pressure control device, and the recess 31 is an integral number of the number of microchips 4 transferred to the chip batch transfer substrate 20, for example, 1 The number of recesses 31 is slightly shallower than the height of the microchip 4 so that the upper surface of the microchip 4 is slightly protruded. It has been set.

  In order to take out the microchip 4 with the vacuum pickup 30, as shown in FIG. 5E, the vacuum pickup 30 is positioned by positioning so that the microchip 4 fits into each recess 31 of the vacuum pickup 30. It is lowered and vacuum suction is performed from the pipe 33. Then, each microchip 4 is attracted and fixed to the recess 31 of the vacuum pickup 30 by the vacuum suction force. In this state, as shown in FIG. 5 (F), the vacuum pickup 30 is raised and the microchip 4 is peeled from the expansion sheet 3. As described above, in the microchip 4 on the push-up pin 14, the contact area with the expansion sheet 3 is also small, so that the adhesive force by the expansion sheet 3 is reduced and it is easy to peel off. Therefore, if the vacuum suction force of the vacuum pickup 30 is larger than the adhesive force by the expansion sheet 3, the microchip 4 can be easily peeled off.

  When the microchips 4 are selectively taken out by the vacuum pickup 30, for example, the chip batch transfer substrate 6 (chip batch shown in FIG. 1D) without passing through the selective take-out sheet 5 shown in FIG. Although it is possible to transfer to the transfer substrate 20), here, the chip position of the microchip 4 is corrected and then transferred to the chip batch transfer substrate 20.

  In the vacuum pickup 30, the size of the recess 31 provided corresponding to the microchip 4 is slightly larger than the actual size of the microchip 4. If the size of the concave portion 31 is exactly the same as the size of the microchip 4, it is necessary to manage the positioning accuracy very strictly. However, if the size of the concave portion 31 is formed larger than the actual size of the microchip 4, there is a possibility that the microchip 4 may be slightly displaced during vacuum suction or may be disadvantageous in that its orientation varies. . Therefore, in this embodiment, a chip position correction plate is used to correct the position, orientation, etc. of each microchip 4 and then transfer it to the chip transfer substrate 20.

  FIGS. 6A to 6G show a chip position correction process. In this chip position correction process, the microchip 4 fitted and separated in the recess 31 of the vacuum pickup 30 is first transferred to the chip position correction plate 40 to correct the position and orientation.

  The chip position correcting plate 40 is placed on a base plate 41, and a pipe 42 for vacuum and pressure air is connected to the air pressure control device. In addition, on the upper surface of the chip position correction plate 40, as many concave portions 43 and through holes 44 as the number of microchips 4 to be transferred to the chip batch transfer substrate 20 are formed. In the case of this embodiment, four times the number of recesses 43 formed in the vacuum pickup 30 is formed. As shown in FIG. 7A, the recess 43 is formed to be slightly larger than the size of the microchip 4, and two orthogonal sides (inner walls of the recess 43) are reference surfaces 43a and 43b for positioning. It is said that. The depth of the recess 43 is set slightly smaller than the height of the microchip 4 so that the upper surface slightly protrudes when the microchip 4 is fitted.

  When the chip position is corrected, first, as shown in FIG. 6 (A), the vacuum pickup 30 is moved to a predetermined position on the chip position correction plate 40, and the vacuum pickup 30 is positioned and positioned as shown in FIG. 6 (B). The pickup 30 is lowered. At this time, the microchip 4 held by the vacuum pickup 30 is fitted into the concave portion 43 of the chip position correcting plate 40. Then, as shown in FIG. 6C, by releasing the vacuum suction of the vacuum pickup 30 and raising the vacuum pickup 30, each microchip 4 held in the recess 31 of the vacuum pickup 30 becomes It moves into the recess 43 of the chip position correcting plate 40. At this time, as shown in FIG. 7A, each microchip 4 is arranged in the concave portion 43 of the chip position correcting plate 40 with a slight positional deviation, orientation variation, and the like.

  Thereafter, as shown in FIG. 6D, the vacuum pickup 30 is slightly moved in the direction opposite to the direction toward the reference surfaces 43a and 43b in the concave portion 43 of the chip position correcting plate 40, and FIG. As shown, the vacuum pickup 30 is lowered to attract the microchip 4 again. Further, the vacuum pick-up 30 is slightly lifted, and as shown in FIG. 6F, the microchip 4 is in the direction of the arrow in the figure (the direction in which the microchip 4 is pressed against the reference surfaces 43a and 43b of the concave portion 43 of the chip position correcting plate 40) And the microchips 4 are attracted to the concave portions 43 of the chip position correcting plate 40. At this time, as shown in FIG. 7 (B), two sides of each microchip 4 are positioned by the reference surfaces 43a and 43b of the recess 43 of the chip position correcting plate 40, and are arranged in an accurate position and orientation. The storage state of the microchip 4 by the chip position correction plate 40 is shown in FIGS. 6 (G) and 7 (B). The same operation is repeated three times to store all the microchips 4 on the chip position correction plate 40 in a state where they are accurately positioned.

  The configuration of the chip position correcting plate 40 is not limited to the above, and for example, a structure as shown in FIG. 8 can be adopted. In the example shown in FIG. 8, the suction position 51 is placed on the base plate 41, and the chip position correcting plate 40 is disposed via the support projection-provided substrate 52 on which the support projection 53 is formed. ing. As described above, the chip position correcting plate 40 is formed with the concave portions 43 and the through holes 44 corresponding to the number of microchips 4 to be transferred to the chip batch transfer substrate 20. When this structure is adopted, as shown in FIG. 8B, the back side of the chip position correcting plate 40 is supported by the support protrusions 53 of the support protrusion-equipped substrate 52 in the region between the recesses 43. Further, the vacuum suction of the microchip 4 is performed through the suction part 51. FIG. 8C shows a state in which the microchip 4 is stored when the above structure is adopted.

  As described above, after the microchip 4 is accurately positioned and stored on the chip position correcting plate 40, the transfer to the chip batch transfer substrate 20 is performed. FIG. 9A to FIG. 9C show this transfer process.

  When transferring, first, as shown in FIG. 9A, the chip batch transfer substrate 20 is arranged on the chip position correcting plate 40, and as shown in FIG. 9B, the chip position correcting plate 40 is placed. The chip batch transfer substrate 20 is overlaid thereon. At this time, positioning pins 61 are planted on the chip position correcting plate 40, and positioning holes 62 are formed in the chip batch transfer substrate 20, and these are fitted and positioned accurately to overlap. Match. Further, the chip batch transfer substrate 20 is placed on the chip position correcting plate 40 so that the adhesive material 22 faces downward and is gently pressed, and the microchip 4 is attached using the adhesive force of the adhesive material 22. Transcript. By stopping the vacuum suction on the chip position correction plate 40 side, the total number of microchips 4 can be transferred to the adhesive material 22. FIG. 9C shows a transfer state of the microchips 4 to the chip batch transfer substrate 20.

  In the present embodiment, since the microchip 4 is taken out using the vacuum pickup 30, when the microchip 4 becomes microscopic, it is necessary to devise a shape around the recess 31 of the vacuum pickup 30, The method of adsorbing the microchip 4 using the vacuum pressure has an advantage that the microchip 4 can be taken out inexpensively without any consumables.

  Further, when the microchip 4 is taken out by using the vacuum pickup 30, as described above, when the microchip 4 becomes fine, it is necessary to devise a shape around the recess 31 of the vacuum pickup 30. This is because the vacuum pressure cannot be used efficiently unless the individual microchips 4 are securely fitted into the recesses 31 and are attracted to the bottom surfaces thereof. For this reason, the size of the recess 31 of the vacuum pickup 30 depends on the processing accuracy of the microchip 4, and the size of the recess 31 is matched to the largest possible size of the microchip 4. When the size of the concave portion 31 of the vacuum pickup 30 is formed larger than the size of the microchips 4 as described above, when the microchip 4 group is simply transferred as it is, it moves in parallel when the microchips 4 are sucked. Therefore, the transfer is performed without correction. In the present embodiment, the minute chip 4 once adsorbed by the vacuum pickup 30 is corrected for positional deviation using the reference surfaces 43a and 43b of the chip position correcting plate 40 and transferred to the chip batch transfer substrate 20. As a result, the chip transfer accuracy is also improved.

It is a schematic perspective view which shows a chip transfer process. It is a figure which shows the chip | tip peeling process in 1st Embodiment. It is a principal part schematic plan view which shows an example of the push-up pin and vacuum suction hole which are provided in a chip | tip peeling plate. It is a figure which shows the chip | tip transfer process to the board | substrate for chip batch transfer in 1st Embodiment. It is a figure which shows the chip | tip peeling process in 2nd Embodiment. It is a figure which shows the chip transfer process to the chip position correction board in 2nd Embodiment. (A) is a top view which shows the state before position correction of a microchip, (B) is a top view which shows the state after position correction of a microchip. It is a figure which shows the other example of a chip position correction board. It is a figure which shows the chip | tip transfer process to the board | substrate for chip batch transfer in 2nd Embodiment.

Explanation of symbols

1 silicon wafer, 2 wafer ring, 3 extension sheet, 4 microchip, 5 selective take-out sheet, 6 chip batch transfer substrate, 7 motherboard, 11 base, 12 porous adsorption plate, 13 chip release plate, 14 push-up pin , 15 Vacuum suction hole, 17 Thermal release sheet, 20 Chip batch transfer substrate, 22 Adhesive material, 30 Vacuum pickup, 31 Recess, 40 Chip position correction plate, 43 Recess, 43a, 43b Reference plane

Claims (14)

A microchip peeling method for selectively peeling microchips from a group of microchips attached on an expansion sheet,
The microchips on the expansion sheet are selectively supported by a plurality of fixed protrusions arranged at predetermined intervals corresponding to the microchips to be peeled off, and by vacuum suction holes provided in the vicinity of the respective fixed protrusions. A microchip peeling method characterized by vacuum-sucking an expansion sheet and peeling a plurality of microchips selected by a chip holding mechanism in this state from the expansion sheet.   2. The microchip peeling method according to claim 1, wherein the vacuum suction is performed through a porous substrate.   The heat release sheet or UV curable sheet having an adhesive surface is used as the chip holding mechanism, and a plurality of microchips are released from the expansion sheet by pressing the adhesive surface against the microchips. 3. The microchip peeling method according to 2.   A vacuum pickup having a microchip fitting portion is used as the chip holding mechanism, and a plurality of microchips are peeled from the expansion sheet by aligning and vacuum-sucking the microchip to be peeled to the microchip fitting portion. The microchip peeling method according to claim 1 or 2.   The microchip sucked and held by the vacuum pickup is moved into a position correcting recess having a reference surface, and each microchip is abutted against the reference surface by moving the vacuum pickup in a predetermined direction, thereby correcting the position. The microchip peeling method according to claim 4, which is performed. A microchip peeling apparatus for selectively peeling microchips from a group of microchips attached on an expansion sheet,
A chip peeling plate having a plurality of fixed protrusions arranged at predetermined intervals corresponding to the microchips to be peeled, and vacuum suction holes provided in the vicinity of each fixed protrusion;
Holding a plurality of microchips to be peeled together and having a chip holding mechanism for peeling from the expansion sheet,
The microchip on the expansion sheet is selectively supported by the fixing protrusion of the chip peeling plate, and the expansion sheet near the fixing protrusion is vacuum-sucked by the vacuum suction hole, and in this state, the chip is selected by the chip holding mechanism. A microchip peeling apparatus for peeling a plurality of microchips from an expansion sheet.   The microchip peeling apparatus according to claim 6, further comprising a porous substrate installed on a back side of the chip peeling plate, and performing vacuum suction through the porous substrate.   The microchip peeling apparatus according to claim 6 or 7, further comprising a thermal peeling sheet or an ultraviolet curable sheet having an adhesive surface as the chip holding mechanism.   8. The microchip peeling apparatus according to claim 6, further comprising a vacuum pickup having a microchip fitting portion as the chip holding mechanism.   The microchip peeling apparatus according to claim 9, further comprising a position correction jig in which a position correction recess having a reference surface is formed.   The microchip peeling apparatus according to claim 10, wherein the position correcting recess has two reference surfaces orthogonal to each other.   The position correction jig includes a position correction substrate in which a position correction recess having a reference surface is formed and a through-hole is formed corresponding to each position correction recess, and for position correction of the position correction substrate. It is comprised from the board | substrate with a protrusion for support | pillar in which the protrusion for support | pillar which supports the area | region between recessed parts from the back was formed, and the adsorption | suction mechanism part which is installed in the back side of the said board | substrate with a protrusion for a support | pillar and has a vacuum suction hole. The microchip peeling apparatus according to claim 10 or 11, characterized in that:   The microchip peeled by the microchip peeling method according to any one of claims 1 to 5 is transferred to a transfer substrate, and the microchips on a plurality of transfer substrates are sequentially transferred to a large area substrate. A method for selective transfer of microchips.   The method of claim 13, wherein the large area substrate is a flat display substrate, and the minute chip is a pixel control element.

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