Transfer method

Abstract

To provide a transfer method that can prevent misalignment of elements after being transferred onto a transferred substrate by blistering.SOLUTION: A transfer method for transferring an element 21 held on a transfer substrate 22 to a transferred substrate 23, comprises: a transfer preparation process for bringing an element 21 held on the transfer substrate 22 and the transferred substrate 23 face to face; transfer process for holding the predetermined element 21 on the transferred substrate 23 by causing blisters 30 on the transferred substrate 22 in or near the holding area of the predetermined element 21; and a blister rupture process for rupturing the blisters 30.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a transfer method that irradiates a transfer substrate with light energy and transfers an element to a target substrate using blistering. [Background Art]

[0002] In recent years, semiconductor chips have been miniaturized for cost reduction, and efforts have been made to mount these miniaturized semiconductor chips with high precision. For mounting these miniaturized chips at high speed, a so-called laser lift-off method has been adopted, in which ablation is caused by irradiating a laser onto the bonding surface between a chip bonded to a transfer substrate and the transfer substrate, so that the chip is peeled from the transfer substrate, energized and transferred to a target substrate.

[0003] Patent Document 1 discloses a technique of ablating a blistering layer by irradiating a laser beam onto the blistering layer which is provided on a transfer substrate and has an adhesive layer on the surface side. In this blistering layer, ablation generates blisters (swellings), and the generation of blisters pushes out the article (element) adhered to the adhesive layer, thereby separating the article from the transfer substrate. [Prior Art Documents] [Patent Documents]

[0004] [Patent Document 1] Japanese National Publication of International Patent Application No. 2014-515883 [Summary of the Invention] [Problems to be Solved by the Invention]

[0005] However, in the method for transferring elements shown in Patent Document 1, there was a risk that the elements transferred to the substrate to be transferred may be misaligned. Specifically, as shown in Figure 7(a), when a laser beam 111 is irradiated onto the blistering layer 124 of the transfer substrate 122 to create a blister 130 and transfer the element 121 to the substrate to be transferred 123, depending on the size of the blister 130, as shown in Figure 7(b), the blistering layer 124 may remain attached to the element 121 even after the entire element 121 has been transferred to the catch layer 125 on the substrate to be transferred 123, until the blister 130 deflates. Here, if the adhesive force of the catch layer 125 is not sufficiently greater than the adhesive force of the blistering layer 124, for example, when the transfer substrate 122 and the substrate to be transferred 123 are moved relative to each other to change the spacing between the elements, there was a problem that the element 121 would be pulled by the blistering layer 124 that was still attached to the element 121, causing misalignment, as shown in Figure 7(c).

[0006] In view of the above-mentioned problems, the present invention aims to provide a transfer method that can prevent misalignment of elements after they have been transferred onto a substrate by blistering. [Means for solving the problem]

[0007] To solve the above problems, the present invention provides a transfer method for transferring an element held on a transfer substrate to a substrate to be transferred, characterized by comprising: a transfer preparation step of facing the element held on the transfer substrate and the substrate to be transferred; a transfer step of holding the predetermined element on the substrate to be transferred by generating a blister on the transfer substrate in or near the holding region of the predetermined element; and a blister rupture step of rupturing the blister.

[0008] According to the transfer method of the present invention, by having a blister rupture step, the blister used for transferring the element to the substrate can be forcibly deflated and separated from the element, thereby preventing misalignment of the element caused by the blister.

[0009] Furthermore, in the transfer step, it is preferable to generate the blister on the transfer substrate by irradiation with active energy rays, and in the blister rupture step, it is preferable to rupture the blister by irradiation with active energy rays.

[0010] This allows the blister rupture process to be carried out without the need for a large amount of equipment.

[0011] Furthermore, in the blister rupture step, it is preferable to rupture the blister by concentrating the irradiation positions of the blister with multiple activation energy rays more closely than in the transfer step.

[0012] This allows for the application of sufficient energy locally to cause the blister to burst.

[0013] In the transfer step, the blister is formed by intermittently irradiating the active energy ray while moving the irradiation position of the active energy ray near the holding position of the predetermined element, and in the blister rupture step, it is preferable to shorten the time interval between the emission of the active energy ray compared to the transfer step, thereby concentrating the irradiation positions of multiple active energy rays.

[0014] On the other hand, in the transfer step, the blister is formed by intermittently irradiating the active energy ray while moving the irradiation position of the active energy ray near the holding position of the predetermined element, and in the blister rupture step, the speed at which the irradiation position of the active energy ray moves is reduced or stopped compared to the transfer step, thereby concentrating multiple irradiation positions of the active energy ray.

[0015] Furthermore, in the blister rupture step, it is preferable to rupture the blister by increasing the energy density of the active energy rays compared to the transfer step.

[0016] This allows for the application of sufficient energy locally to cause the blister to burst.

[0017] Here, in the blister bursting step, it is preferable to increase the energy density of the active energy ray by adjusting the irradiation height of the active energy ray to position the transfer substrate closer to the focal point of the active energy ray than in the transfer step.

[0018] On the other hand, in the blister bursting step, the energy density of the active energy ray may be increased by increasing the output energy of the active energy ray.

[0019] It is also preferable to further comprise an alignment direction moving step of relatively moving the transfer substrate and the transfer-receiving substrate in the alignment direction of the elements on the transfer substrate after the blisters have burst.

[0020] By doing so, it is possible to avoid a state where blisters remain attached to the elements when the alignment direction moving step is performed, thereby preventing the elements from being pulled by the blisters and causing positional displacement during the alignment direction moving step.

Effects of the Invention

[0021] The transfer method of the present invention can prevent positional displacement of elements after the elements are transferred onto a transfer-receiving substrate by blistering. Brief Description of Drawings

[0022] [Figure 1] It is a diagram illustrating a transfer apparatus for carrying out the transfer method of the present invention. [Figure 2] It is a diagram illustrating a transfer step in one embodiment of the present invention. [Figure 3] It is a diagram illustrating a blister bursting step in one embodiment of the present invention. [Figure 4] It is a diagram illustrating a blister bursting step in another embodiment of the present invention. [Figure 5] It is a diagram illustrating a transfer method in one embodiment of the present invention. [Figure 6]It is a diagram illustrating a transfer step and a blister rupture step in another embodiment of the present invention. [Figure 7] It is a diagram illustrating an example of failed transfer of an element in a conventional transfer method. DETAILED DESCRIPTION OF THE INVENTION

[0023] A transfer apparatus for carrying out the transfer method of the present invention will be described with reference to FIG. 1.

[0024] The transfer apparatus 10 includes a laser irradiation unit 12 that emits a laser beam 11, a transfer substrate holding unit 13 that holds a transfer substrate 22 and is movable at least in the X-axis direction and the Y-axis direction, a target substrate holding unit 14 that is located below the transfer substrate holding unit 13 and holds a target substrate 23 so as to face the transfer substrate 22 with a gap therebetween, and a control unit (not shown). By irradiating the transfer substrate 22 with the laser beam 11, ablation occurs in the transfer substrate, and the element 21 is transferred from the transfer substrate 22 to the target substrate 23.

[0025] The laser irradiation unit 12 is an embodiment of the energy irradiation unit in the present invention, which is an apparatus that emits a laser beam 11 such as an excimer laser that is an active energy ray, and is fixedly provided in the transfer apparatus 10. In the present embodiment, the laser irradiation unit 12 intermittently emits a spot-shaped laser beam 11. The irradiation position of the laser beam 11 in the X-axis direction and the Y-axis direction is controlled via a galvano mirror 15 whose angle is adjusted by the control unit and an Fθ lens 16, and the laser beam 11 selectively irradiates a plurality of elements 21 arranged on the transfer substrate 22 held by the transfer substrate holding unit 13. When the laser beam 11 enters the vicinity of the element 21 through the transfer substrate 22, ablation occurs between the transfer substrate 22 and the element 21 due to the application of active energy (light energy), the element 21 is urged by this ablation, and the element 21 is transferred from the transfer substrate 22 to the target substrate 23. In the present description, the element 21 is, for example, a semiconductor chip.

[0026] Furthermore, the transfer apparatus 10 has a mirror 17a that reflects the laser light 11 emitted from the laser emission unit 12 directly downward (in the Z-axis direction), and a mirror 17b that reflects the laser light 11 reflected by mirror 17a and directs it into the galvanometer mirror 15. In addition, an optical system such as an expander lens and a collimating lens (not shown) is provided between the laser emission unit 12 and the mirror 17a.

[0027] Furthermore, the mirror 17b, galvanometer mirror 15, and Fθ lens 16, enclosed by the dashed line in Figure 1, are mounted on a common frame and can move together in the Z-axis direction. By moving them in the Z-axis direction, the focal position of the laser beam 11 in the Z-axis direction near the transfer substrate 22 can be adjusted.

[0028] The transfer substrate gripping portion 13 has an opening and grips the vicinity of the outer periphery of the transfer substrate 22 by suction. Laser light 11 emitted from the laser irradiation portion 12 can be directed onto the transfer substrate 22 held by the transfer substrate gripping portion 13 through this opening.

[0029] The transfer substrate 22 is a substrate made of glass or the like that can transmit laser light 11, and holds the element 21 on its lower surface. A blistering layer 24 is formed on the surface of the transfer substrate 22 that holds the element 21, and the surface of this blistering layer 24 is adhesive. The adhesive force of the surface of this blistering layer 24 becomes the holding force of the element 21, and the element 21 is held in place by adhesion.

[0030] Furthermore, the transfer substrate gripping portion 13 moves relative to the substrate gripping portion 14 in at least the X-axis and Y-axis directions by a moving mechanism (not shown). A control unit (not shown) controls this moving mechanism and adjusts the position of the transfer substrate gripping portion 13, thereby adjusting the relative position of the element 21 held on the transfer substrate 22 with respect to the substrate 23. The transfer substrate gripping portion 13 may also be movable in the Z-axis direction, and the relative height of the transfer substrate gripping portion 13 with respect to the substrate gripping portion 14 may be adjusted according to the thickness of the transfer substrate 22 and the substrate 23.

[0031] The substrate gripping portion 14 has a flat surface on its upper surface and grips the substrate 23 during the element transfer process so that the blistering layer 24 of the transfer substrate 22 and the element 21 held by the blistering layer 24 face the transfer surface of the substrate 23. Multiple suction holes are provided on the upper surface of the substrate gripping portion 14, and the back surface of the substrate 23 (the side on which the element 21 is not transferred) is gripped by suction force.

[0032] In this embodiment, the substrate 23 to be transferred is a substrate made of glass or the like, and an adhesive catch layer 25 is provided on the transfer surface (the surface that receives the element 21) to hold the element 21 transferred from the transfer substrate 22 in an adhesive manner.

[0033] In this embodiment, the transfer substrate gripping portion 13 moves in the X-axis and Y-axis directions, causing the transfer substrate gripping portion 13 and the substrate to be transferred gripping portion 14 to move relative to each other in the XY direction. However, if the dimensions of the substrate to be transferred 23 are large and the entire surface of the substrate to be transferred 23 cannot be positioned directly below the irradiation range of the laser beam 11, the substrate to be transferred gripping portion 14 may also be provided with a mechanism for movement in the X-axis and Y-axis directions.

[0034] In the transfer apparatus 10 having the above configuration, when the transfer substrate 22 and the substrate to be transferred 23 are facing each other with the element 21 in between, laser light 11 is irradiated from the transfer substrate 22 toward the element 21, and when the laser light 11 is irradiated onto the blistering layer 24, the energy of the laser light 11 causes a portion of the material of the blistering layer 24 to decompose and gas is generated. Due to this decomposition of the material of the blistering layer 24 and the generation of gas, a blister (bubble) 30 is generated inside the blistering layer 24 or between the glass surface 22a of the transfer substrate 22 and the blistering layer 24, as shown in Figure 1. In this explanation, the phenomenon in which such a blister 30 is generated is called blistering.

[0035] An embodiment of the transfer process, which is one step in the transfer method using the transfer apparatus of the present invention, will be explained with reference to Figure 2. Figure 2(a) is a view along the arrow AA in Figure 1, and Figure 2(b) is a front view including the transfer substrate 22 and the substrate to be transferred 23.

[0036] In the transfer process of this embodiment, as shown in Figure 2(a), the laser beam 11 is irradiated multiple times in the region (dashed line in Figure 2(a)) where one element 21 is held in the blistering layer 24 provided on the transfer substrate 22, while changing the irradiation position. This connects the small blisters generated at each irradiation position to form one large dome-shaped blister 30 as shown in Figure 2(b). By forming the blister 30 in this way, the element 21 is brought closer to the transfer substrate 23 while being held on the surface portion of the blistering layer 24, and the contact area between the blistering layer 24 and the element 21 is reduced, thereby transferring the element 21 from the transfer substrate 22 to the transfer substrate 23. In this embodiment, the change in the irradiation position of the laser beam 11 (hereinafter also called the irradiation spot) is performed by the galvanometer mirror 15, which is an irradiation position control unit, as described above.

[0037] In this embodiment, the trajectory of the laser beam 11's irradiation spot is roughly spiral-shaped, as shown in Figure 2(a), with repeated linear movement in the X-axis direction, a 90-degree rotation in the direction of movement, linear movement in the Y-axis direction, and a 90-degree rotation in the direction of movement. The laser beam 11 is irradiated so that the spacing between each irradiation spot is roughly uniform.

[0038] Next, an embodiment of the blister rupture step, which is one of the steps in the transfer method, will be described using Figure 3. Figure 3(a) is a view along the arrow AA in Figure 1, and Figure 3(b) is a front view including the transfer substrate 22 and the substrate to be transferred 23.

[0039] The blister rupture step in this invention is a step in which the blister 30 formed for the transfer of the element 21 is deliberately ruptured and deflated. In this embodiment, similar to the transfer step, the blister 30 is ruptured using laser light 11 emitted from the laser emission unit 12 and irradiated onto the transfer substrate 22.

[0040] Specifically, in the blister rupture process, a larger amount of energy than during the transfer process is locally applied to a portion of the blistering layer 24 surrounding the blister 30. As a result, a rupture portion 24a, which is a through-hole, is formed in the blistering layer 24 at the location where this large amount of energy is applied, as shown in Figure 3(b). This causes the blister 30 to rupture. When the blister 30 ruptures in this way, the gas inside the blister 30 escapes to the outside, and the blister 30 deflates. At that time, if the holding force of the element 21 by the catch layer 25 is greater than the holding force of the element 21 by the blistering layer 24, the blistering layer 24 peels off from the element 21 and separates as the blister 30 deflates. In this way, the blister rupture process forces the blistering layer 24 to separate from the element 21.

[0041] In this embodiment, in order to locally apply greater energy to the blistering layer 24 during the blister rupture process than during the transfer process, the positions of multiple irradiation spots are densely packed, as shown in the planned irradiation position 26c, compared to the spacing between positions where irradiation spots can be formed during the transfer process, such as the planned irradiation positions 26a and 26b shown in Figure 3(a). By densely packing the irradiation spots in this way, even if the same output laser light 11 as during the transfer process is used, sufficient energy to form the rupture portion 24a can be locally applied.

[0042] As a method for concentrating the irradiation spots in the blister rupture process, for example, the time interval between laser beams 11 emitted by the laser emission unit 12 can be shortened compared to the transfer process, or the movement speed of the galvanometer mirror 15 that controls the irradiation position can be reduced or stopped compared to the transfer process. In particular, by reducing or stopping the movement speed of the galvanometer mirror 15, the irradiation spots can be concentrated while the laser emission unit 12 maintains a state of emitting laser beams 11 of a constant output at constant time intervals, thereby avoiding disruption in the control of the laser beams 11.

[0043] Next, the blister rupture process in another embodiment of the present invention will be described with reference to Figure 4.

[0044] In the blister rupture process described above, sufficient energy to form the rupture portion 24a was locally applied by using multiple laser beams 11 with densely packed irradiation spots. In contrast, in the blister rupture process shown in Figures 4(a) and 4(b), the energy density of the laser beams 11 irradiated onto the blistering layer 24 is made higher than the energy density of the laser beams 11 used in the transfer process. This allows a small number of laser beams 11 to locally apply sufficient energy to form the rupture portion 24a, causing the blister to rupture.

[0045] Specifically, in the blister rupture process shown in Figure 4(a), the parameters of the laser light 11 emitted from the laser emission unit 12 are adjusted. In order to form an irradiation spot at the planned irradiation position 26d for the blister rupture process, the laser emission unit 12 emits the laser light 11 with a higher emission energy than when forming irradiation spots in other processes (such as the transfer process).

[0046] Furthermore, in the blister rupture process shown in Figure 4(b), the heights of the mirror 17b, galvanometer mirror 15, and Fθ lens 16 shown in Figure 1 are changed from those in the transfer process. In order to form an irradiation spot at the planned irradiation position 26e for the blister rupture process, the blistering layer 24 is positioned closer to the focal point of the laser beam 11 than in the transfer process, thereby increasing the energy density of the laser beam 11.

[0047] In the transfer process, the irradiation optical system for the laser beam 11 is adjusted so that a substantially uniform amount of energy is applied to a predetermined area with a single irradiation of the laser beam 11, and the transfer substrate 22 containing the blistering layer 24 is intentionally positioned at a location outside the focal point of the laser beam 11. In contrast, in the blister bursting process, the blistering layer 24 is positioned closer to the focal point of the laser beam 11 than in the transfer process, which reduces the size of the irradiation spot in the blistering layer 24 and increases the energy density. Therefore, even if the output of the laser beam 11 emitted from the laser emission unit 12 is the same during the transfer process and the blister bursting process, it is possible to create a difference in energy density at the irradiation spot, and this can be used to locally apply enough energy to form the burst portion 24a during the blister bursting process.

[0048] Furthermore, in the examples shown in Figures 4(a) and 4(b), the high-energy-density laser beam 11 is irradiated only once, but it may be irradiated multiple times.

[0049] Next, a series of steps in the transfer method according to one embodiment of the present invention will be explained using Figure 5.

[0050] First, as shown in the left half of Figure 5(a), the transfer substrate 22 holds the element 21, and with the element 21 and the substrate to be transferred 23 separated, the transfer substrate 22 and the substrate to be transferred 23 are placed facing each other so as to sandwich the element 21. In this explanation, this step is referred to as the transfer preparation step.

[0051] Next, as shown in the right half of Figure 5(a), a laser beam 11 is irradiated near a predetermined element 21 to create a blister 30 in the blistering layer 24, thereby bringing the element 21 closer to the transfer substrate 23 and holding it in place on the transfer substrate 23. This process is called the transfer process, as described above.

[0052] Figure 5(b) shows the state in which the transfer process has progressed, and the holding area of ​​one element 21 has been irradiated with laser light 11 multiple times, forming a large blister 30, and the entire element 21 has been transferred to the catch layer 25 of the transfer substrate 23 with the blistering layer 24 still attached to the element 21.

[0053] Next, as shown in Figure 5(c), a rupture section 24a is provided in the blistering layer 24 surrounding the blister 30, causing the blister 30 to rupture. This process is called the blister rupture process, as described above. As the blister 30 ruptures, it deflates, and the blistering layer 24 separates from the element 21.

[0054] After the elements 21 transferred to the substrate 23 and the blistering layer 24 are completely separated by the blister rupture process, the transfer substrate 22 and the substrate 23 move relative to each other in the direction of the arrangement of the elements 21 on the transfer substrate 22 (the X-axis direction in Figure 5), as shown in Figure 5(d). In this description, this process is referred to as the arrangement direction movement process. In this embodiment, the transfer substrate 22 and the substrate 23 move relative to each other as the transfer substrate gripping portion 13 moves in the X-axis direction.

[0055] As a result of this alignment direction movement process, the pitch of the elements 21 on the transfer substrate 22, which was originally a distance P1 as shown in Figure 5(a), can be arbitrarily adjusted, and multiple elements 21 can be arranged on the transfer substrate 23 at any pitch, as will be described later.

[0056] Here, if we were to attempt to carry out the alignment direction movement process without the blister rupture process as in the conventional method, the blistering layer 24 may continue to adhere to the element 21 even after the entire surface of the element 21 that is held by the transfer substrate 23 has been held by the transfer substrate 23, until the blister 30 naturally deflates.

[0057] Furthermore, if the alignment direction movement process is carried out while the blistering layer 24 remains attached to the element 21, the element 21 on the transfer substrate 23 may be pulled by the blistering layer 24, potentially causing misalignment.

[0058] Whether or not the blistering layer 24 causes the element 21 to shift position depends on several factors: if it is due to the blistering layer 24, it depends on variations in the pressing force and adhesion to the catch layer 25 due to the size and shape of the blister 30, and variations in the adhesive strength and thickness of the blistering layer 24 itself. If it is due to the element 21, it depends on the non-uniformity of the shape of the element 21 and the resulting variations in adhesion to the catch layer. If it is due to the catch layer 25, it depends on variations in its adhesive strength and thickness. If it is due to the laser beam 11, it depends on variations in its irradiation position and energy distribution.

[0059] In contrast, in the present invention, a blister rupture step is provided before the alignment direction movement step, so that the element 21 is completely separated from the blistering layer 24 at the start of the alignment direction movement step. Therefore, it is possible to prevent the misalignment of the element 21 on the transfer substrate 23 as described above.

[0060] Once the transfer substrate 22 and the substrate to be transferred 23 have moved relative to each other by a predetermined distance through the alignment direction movement process, the next element 21 to be transferred will be facing the substrate to be transferred 23, which corresponds to the completion of the transfer preparation process for the next element 21. Then, as shown in Figure 5(e), the transfer process for the next element 21 is performed by irradiating the next element 21 with laser light 11.

[0061] As described above, through the transfer preparation process, transfer process, blister bursting process, and alignment direction movement process, the pitch of the elements 21 on the substrate to be transferred 23 is adjusted to an arbitrary pitch with respect to the pitch of the elements 21 on the transfer substrate 22 (distance P1), as shown by distance P2 in Figure 5(e), and then the next element 21 is transferred from the transfer substrate 22 to the substrate to be transferred 23.

[0062] The above transfer method makes it possible to prevent misalignment of the elements after they have been transferred onto the substrate by blistering.

[0063] Herein, the transfer method of the present invention is not limited to the embodiments described above, but may be other embodiments within the scope of the present invention. For example, in the above description, the trajectory of the movement of the irradiation spot is roughly spiral-shaped as shown in Figure 2(a), but it is not limited to this, and may be zigzag-shaped as shown in Figure 6, for example.

[0064] Furthermore, if the area of ​​element 21 is sufficiently small, the laser light 11 may be irradiated only once during a single transfer process.

[0065] Furthermore, in the above description, the blister rupture process is performed after the entire element 21 has been transferred to the transfer substrate 23. However, this is not limited to this, for example, as shown in Figure 5(a), if the transfer process has a configuration in which a part of the element 21 comes into contact with the transfer substrate 23 first, and then the portion held by the transfer substrate 23 gradually increases until the entire element 21 is eventually held by the transfer substrate 23, the blister rupture process may be performed when a part of the element 21 is held by the transfer substrate 23.

[0066] Furthermore, in the above explanation, the laser beam 11 is irradiated into the element holding region shown by the dashed line in Figure 3(a), etc. However, the laser beam 11 may be irradiated in the vicinity of the element holding region and around the element holding region, provided that blistering brings the predetermined element 21 closer to the transfer substrate 23.

[0067] Furthermore, it is not necessarily required that the blistering layer 24 adheres to all elements 21 on the transfer substrate 22 even after transfer to the substrate 23. In cases where there is a risk that the blistering layer 24 may adhere to some elements 21 even after transfer to the substrate 23, the transfer method having a blister rupture step as described in the present invention can be suitably used.

[0068] Furthermore, in the above explanation, the blister rupture process involves irradiating the blister 30 from above through the transfer substrate 22 with laser light 11, similar to the transfer process. However, this is not limited to this method; for example, a separate laser beam for rupture, distinct from the blistering laser light 11, may be irradiated onto the blister 30 from the side to cause it to rupture.

[0069] Furthermore, the means of rupturing the blister 30 is not limited to laser light; for example, the blister 30 may also be ruptured with a needle or the like.

[0070] Furthermore, while the blistering layer and catch layer are described above as holding the element by adhesive force, the element may also be held by a holding force other than adhesive force. [Explanation of Symbols]

[0071] 10 Transfer device 11. Laser light (active energy rays) 12. Laser light source (energy irradiation section) 13 Transfer substrate gripping section 14 Transferred substrate gripping part 15 Galvano Mirror 16 Fθ lens 17a Miller 17b Miller 21 elements 22 Transfer substrate 22a Glass surface 23 Substrate to be transferred 24 blistering layers 24a Rupture part 25 Catch Layer 26a~e Planned irradiation locations 30 Blisters 111 Laser light 121 elements 122 Transfer substrate 123 Substrate to be transferred 124 blistering layers 125 Catch Layer 130 Blister

Claims

1. This is a transfer method for transferring an element held on a transfer substrate to a substrate to be transferred. A transfer preparation step in which the element held on the transfer substrate and the substrate to be transferred are brought into contact, A transfer step in which a predetermined element is held on the transfer substrate by causing a blister to form on the transfer substrate in or near the holding region of the predetermined element, After the predetermined element is held on the substrate to be transferred by the transfer step, a blister rupture step is performed to rupture the blister, A transfer method characterized by having the following features.

2. The transfer method according to claim 1, characterized in that, in the transfer step, a blister is generated on the transfer substrate by irradiation with an active energy ray, and in the blister rupture step, the blister is ruptured by irradiation with an active energy ray.

3. The transfer method according to claim 2, characterized in that the blister rupture step involves rupturing the blister by concentrating the irradiation positions of the blister with multiple active energy rays more closely than in the transfer step.

4. The transfer method according to claim 3, characterized in that, in the transfer step, the blister is formed by intermittently irradiating with an active energy ray while moving the irradiation position of the active energy ray near the holding position of the predetermined element, and in the blister rupture step, the time interval between the emission of the active energy ray is shortened compared to the transfer step, thereby concentrating multiple irradiation positions of the active energy ray.

5. The transfer method according to claim 3, characterized in that, in the transfer step, the blister is formed by intermittently irradiating the active energy ray while moving the irradiation position of the active energy ray near the holding position of the predetermined element, and in the blister rupture step, the speed of movement of the irradiation position of the active energy ray is reduced or stopped compared to the transfer step, thereby concentrating multiple irradiation positions of the active energy ray.

6. The transfer method according to claim 2, characterized in that the blister rupture step is performed by increasing the energy density of the active energy rays compared to the transfer step, thereby causing the blister to rupture.

7. The transfer method according to claim 6, characterized in that, in the blister rupture step, the energy density of the active energy rays is increased by adjusting the irradiation height of the active energy rays to position the transfer substrate closer to the focal point of the active energy rays than during the transfer step.

8. The transfer method according to claim 6, characterized in that the energy density of the active energy rays is increased by increasing the emission energy of the active energy rays in the blister rupture step.

9. The transfer method according to claim 1, further comprising an alignment direction movement step of moving the transfer substrate and the substrate to be transferred relative to each other in the direction of the arrangement of elements on the transfer substrate after the blister has burst.

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