Transfer method and transfer device

Abstract

To transfer elements such as semiconductor chips with high precision by using a simple configuration.SOLUTION: A transfer method in which elements 1 which are arranged in at least a first direction on a first main surface of a transfer substrate 20 while held on a holding layer 10 are transferred onto a transfer target substrate by laser lift-off executes a first element step in which at a first laser spot having a size that allows irradiation on a region wider than the entire region of at least one first element to be transferred, a laser beam is applied to a region centered on the holding layer holding a first element as a transfer target from a second main surface side of the transfer substrate, the holding layer that holds the entire region of the first element to be transferred is irradiated with a laser beam having an energy capable of separating the first element to be transferred, and the first element is transferred to the transfer target substrate 30.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a transfer method and a transfer apparatus for transferring an element such as a semiconductor chip with high precision. [Background technology]

[0002] Semiconductor chips are becoming smaller to reduce costs, and efforts are being made to mount LED chips, which are particularly small semiconductor chips, at high speed and with high precision.In particular, LEDs used in displays require LED chips called micro LEDs, which are 50μm x 50μm or less in size, to be mounted quickly and with a precision of a few μm.

[0003] Patent Document 1 describes a technique for transferring a semiconductor chip held on a substrate via a retaining layer by laser lift-off, in which the retaining layer is irradiated with a laser with a laser spot of the same size as the semiconductor chip. It also describes that if the retaining layer does not wrap around the side surface of the semiconductor chip, the semiconductor chip does not tilt during laser lift-off and can be transferred with high precision. [Prior art documents] [Patent documents]

[0004] Patent document 1: WO2020 / 166301 publication Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technique described in Patent Document 1 irradiates a laser onto a holding layer that adheres to a semiconductor chip with a laser spot of the same size as the semiconductor chip, which poses the problem of high cost because it is necessary to improve the positional accuracy of the laser irradiation in order to target a miniaturized semiconductor chip. Also, in order to eliminate the entire holding layer that adhesively holds a semiconductor chip by irradiating a laser with a laser spot of the same size as the semiconductor chip as in the technique described in Patent Document 1, an optical system that provides a cross-sectional profile of the laser that makes the irradiated surface flat is required, which poses the problem of a complex device.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to solve the above problems and to transfer elements such as semiconductor chips with high accuracy using a simple structure. [Means for solving the problem]

[0007] In order to solve the above problems, the present invention provides a transfer method for transferring elements arranged in at least a first direction on a first main surface of a transfer substrate and held by a holding layer to a transfer substrate by laser lift-off, the method comprising the steps of: irradiating the holding layer with a laser from the second main surface side of the transfer substrate, the holding layer being centered on an area holding the first element to be transferred, with a first laser spot having a size that allows the holding layer to be irradiated with a region wider than the entire area of ​​at least one first element to be transferred; A first element transfer step is performed in which the holding layer that holds the entire area of ​​the first element to be transferred is irradiated with a laser having energy capable of separating the first element, and the first element to be transferred is transferred to a transfer substrate. death, The region having energy capable of separating from the retention layer is larger than the entire area of ​​the first element and is large enough to include a part of the half of the adjacent element adjacent to the first element on the first element side. The present invention provides a transfer method comprising the steps of:

[0008] With this configuration, since the laser is irradiated with the first laser spot wider than the first element, the holding layer to which the element is adhered can be irradiated with the laser without performing highly accurate alignment. Also, even if a laser having a cross-sectional profile of an energy distribution that is maximum at the center of the first laser spot and weakens with distance in the width direction perpendicular to the irradiation direction (for example, a laser having a cross-sectional profile of a Gaussian distribution) is used, it is possible to irradiate the entire surface of the holding layer that holds the element with a laser energy that can separate the element, so that an element such as a semiconductor chip can be transferred with high accuracy with a simple configuration.

[0009] A transfer method, wherein the first laser spot has an energy distribution that is maximum at the center of a cross-sectional profile and becomes weaker as it moves away in a width direction perpendicular to an irradiation direction. Is It may be a configuration.

[0010] With this configuration, the laser is irradiated with a first laser spot that is wider than the first element and narrower than the area including the half of the adjacent element on the first element side, so that the holding layer adhering the first element can be irradiated with the laser without high-precision alignment. Also, since the part of the holding layer that holds the adjacent element is also irradiated with energy that can separate the element, the adjacent element is not transferred, but even if the holding layer wraps around the side of the adjacent element, the wrapped holding layer is ablated by the irradiation of the laser light, and the adjacent chip can be transferred stably after this.

[0013] A transfer method comprising the steps of: Adjacent to the first element A second element transfer process may be performed in which at least one second element arranged adjacent to the opposite side of the first element in the adjacent elements is transferred to a transfer substrate by irradiating a laser with the first laser spot from the second main surface side of the transfer substrate to an area centered on the holding layer that holds the second element.

[0014] With this configuration, by irradiating the second element with the first laser spot, it is possible to irradiate the entire surface of the holding layer holding the element with laser energy sufficient to separate the element, even if the laser has a cross-sectional profile of energy distribution that becomes weaker the farther in the width direction perpendicular to the irradiation direction. Therefore, elements such as semiconductor chips can be transferred with high precision using a simple configuration.

[0015] The transfer method may further include a transfer substrate having elements arranged and held via a holding layer in a second direction perpendicular to the first direction, and after the second element transfer step, a third element transfer step is carried out in which a third element arranged adjacent to the adjacent element in the second direction is transferred to a transferee substrate by irradiating a laser from the second main surface side of the transfer substrate with the first laser spot onto an area centered on the holding layer holding the third element.

[0016] With this configuration, by irradiating the holding layer that adheres the third element with the first laser spot, it is possible to irradiate the entire surface of the holding layer that holds the element with laser energy sufficient to separate the element, even if the laser has a cross-sectional profile of energy distribution that becomes weaker the farther in the width direction perpendicular to the irradiation direction. Therefore, elements such as semiconductor chips can be transferred with high precision using a simple configuration.

[0017] A transfer method comprising the steps of: The first laser spot is applied to the adjacent element. to, Alternatively, the transfer method described in claim 5 may be carried out by irradiating the holding layer holding the adjacent element from the second main surface side of the transfer substrate with a laser using a second laser spot smaller than the first laser spot, thereby transferring the adjacent element to a transfer substrate.

[0018] By performing the first element transfer process, the second element transfer process, and the third element transfer process, the retaining layer contacts the adjacent element only in an area equal to or closer to the surface of the adjacent element that is closest to the retaining layer, and the retaining layer does not wrap around the side of the adjacent element, so that the adjacent element can be transferred with high precision even when the laser is irradiated with a second laser spot that is smaller than the first laser spot. Effect of the Invention

[0021] The transfer method and transfer device of the present invention make it possible to transfer elements such as semiconductor chips with high precision using a simple configuration. [Brief description of the drawings]

[0022] [Figure 1] FIG. 2 is a diagram illustrating a transfer device according to the first embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram for explaining a laser profile in Example 1 of the present invention, where (a) shows a cross section of a support layer and an element, and (b) shows a cross-sectional profile of the laser. [Diagram 3] FIG. 2 is a diagram for explaining a laser profile in the first modified example of the present invention, where (a) shows a cross section of a support layer and an element, and (b) shows a cross-sectional profile of the laser. [Figure 4] 5A and 5B are diagrams for explaining a laser profile in Modification 2 of the present invention, where (a) shows a cross section of a support layer and an element, and (b) shows a cross-sectional profile of the laser. [Diagram 5] 4A to 4C are diagrams illustrating a first element transferring step and a second element transferring step in the first embodiment of the present invention. [Figure 6] 5A to 5C are diagrams illustrating a third element transfer step in the first embodiment of the present invention. [Figure 7] 6A to 6C are diagrams illustrating another first element transferring step and another second element transferring step in the first embodiment of the present invention. [Figure 8] 6A to 6C are diagrams illustrating another third element transfer step in the first embodiment of the present invention. [Figure 9]6A to 6C are diagrams illustrating another first element transferring step and another second element transferring step in the first embodiment of the present invention. [Figure 10] 4A to 4C are diagrams illustrating an adjacent element transfer step in the first embodiment of the present invention. [Figure 11] 5A to 5C are diagrams illustrating another adjacent element transfer process in the first embodiment of the present invention. [Figure 12] 10A to 10C are diagrams illustrating a first element transferring step and a second element transferring step in Example 2 of the present invention. [Figure 13] 11A to 11C are diagrams illustrating a third element transfer step in Example 2 of the present invention. [Figure 14] 10A to 10C are diagrams illustrating another first element transferring step and another second element transferring step in the second embodiment of the present invention. [Figure 15] 10A to 10C are diagrams illustrating another first element transferring step and another second element transferring step in the second embodiment of the present invention. [Figure 16] 10A to 10C are diagrams illustrating another first element transfer step in Example 2 of the present invention. [Figure 17] 11A to 11C are diagrams illustrating an adjacent element transfer step in the second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0023] A first embodiment of the present invention will be described with reference to FIGS. 1 to 11. FIG. 1 is a diagram for explaining a transfer device in a fourth embodiment of the present invention. FIG. 2 is a diagram for explaining a laser profile in the first embodiment of the present invention, where (a) shows a cross section of a retaining layer and an element, and (b) shows a cross-sectional profile of the laser. FIG. 3 is a diagram for explaining a laser profile in a first modified example of the present invention, where (a) shows a cross section of a retaining layer and an element, and (b) shows a cross-sectional profile of the laser. FIG. 4 is a diagram for explaining a laser profile in a second modified example of the present invention, where (a) shows a cross section of a retaining layer and an element, and (b) shows a cross-sectional profile of the laser. FIG. 5 is a diagram for explaining a first element transfer step and a second element transfer step in the first embodiment of the present invention. FIG. 6 is a diagram for explaining a third element transfer step in the first embodiment of the present invention. FIG. 7 is a diagram for explaining another first element transfer step and another second element transfer step in the first embodiment of the present invention. FIG. 8 is a diagram for explaining another third element transfer step in the first embodiment of the present invention. FIG. 9 is a diagram for explaining another first element transfer step and another second element transfer step in the first embodiment of the present invention. Fig. 10 is a diagram for explaining an adjacent element transfer process in the embodiment 1 of the present invention. Fig. 11 is a diagram for explaining another adjacent element transfer process in the embodiment 1 of the present invention.

[0024] (Transfer Apparatus) The transfer apparatus 100 in the first embodiment includes a transfer section 110. The transfer section 110 performs a first element transferring step, a second element transferring step, a third element transferring step, and an adjacent element transferring step.

[0025] 1 shows the details of the transfer unit 110. The transfer unit 110 includes a laser irradiation unit 112 that irradiates laser light 111, a transfer substrate holding unit 113 that holds a transfer substrate and is movable at least in the X-axis and Y-axis directions, a transferred substrate holding unit 114 that is located below the transfer substrate holding unit 113 and holds a transferred substrate so as to face the transfer substrate approximately parallel with a gap therebetween, and a control unit (not shown).

[0026] The laser irradiation unit 112 is a device for irradiating laser light 111 such as an excimer laser, and is fixed to the transfer unit 110. In the first embodiment, the laser irradiation unit 112 irradiates laser light 111 having a cross-sectional profile of a Gaussian distribution, and the irradiation position of the laser light 111 in the X-axis direction and the Y-axis direction is controlled via a galvanometer mirror 115 and an fθ lens 116 whose angle is adjusted by a control unit, and the laser light 111 is selectively irradiated to a plurality of semiconductor chips 1 ("elements" in claims) arranged on a transfer substrate 20 held by a transfer substrate holding unit 113 via a holding layer 10. When the laser light 111 is incident on the holding layer 10 that holds the semiconductor chip 1 of the transfer substrate 20, laser lift-off is performed, and the semiconductor chip 1 flies and is transferred from the transfer substrate 20 to the transferred substrate 30.

[0027] Further, the laser irradiation unit 112 in the first embodiment irradiates a laser from the second main surface side of the transfer substrate 20 to an area centered on the holding layer 10 holding the semiconductor chip 1 with a first laser spot 50 having a size such that the irradiation range of the laser having energy capable of separating the semiconductor chip 1 is wider than the entire area of ​​at least one semiconductor chip 1 to be transferred arranged adjacent to the transfer substrate 20 and is narrower than the area including half of an adjacent semiconductor chip ("adjacent element" in the claims) arranged adjacent to the semiconductor chip 1 in the X direction (first direction). As a result, the holding layer 10 holding the entire semiconductor chip 1 is irradiated with a laser having energy capable of separating the semiconductor chip 1, and the semiconductor chip 1 can be transferred to the transfer substrate 30. Further, in the first embodiment, the first laser spot 50 and the second laser spot 60 having a size smaller than the first laser spot 50 can be irradiated by switching between them using the control unit.

[0028] Here, the vertical axis of Fig. 2(b) is the power of the laser, and the horizontal axis indicates the widthwise spread of the cross-sectional profile. The laser irradiated in Example 1 has an energy distribution that is maximum at the center of the cross-sectional profile of the first laser spot as shown in Fig. 2(b) and becomes weaker as it moves away in the widthwise direction perpendicular to the irradiation direction, and the area having the energy PA capable of separating the semiconductor chip 1 from the retaining layer 10 is wider than the entire semiconductor chip 1, and has a size that is irradiated to an area narrower than the area including half of the adjacent semiconductor chip adjacent to the semiconductor chip 1. Note that P1 on the vertical axis of Fig. 2(b) indicates the energy irradiated to the entire surface of the first semiconductor chip 1.

[0029] In the first embodiment, the laser is irradiated with a first laser spot 50 that is wider than the first semiconductor chip and narrower than the area including half of the adjacent semiconductor chip adjacent to the first semiconductor chip 1, so that the entire semiconductor chip 1 and an area narrower than the area including half of the adjacent semiconductor chip adjacent to the semiconductor chip 1 are irradiated with a laser beam 111 having an energy PA capable of separating the semiconductor chip from the holding layer 10, as shown in FIG. 2(a). This does not require a complex optical system having a laser profile that makes the irradiated surface flat, and the semiconductor chip 1 can be transferred with high accuracy with a simple configuration without performing high-precision alignment. In addition, because a part of the holding layer 10 that holds the adjacent semiconductor chip is also irradiated with energy capable of separating the semiconductor chip, even if the holding layer 10 wraps around the side of the adjacent chip, the holding layer 10 that wraps around is ablated by the irradiation of the laser beam 111, and the adjacent chip can be transferred stably thereafter.

[0030] The transfer substrate holding unit 113 has an opening and adsorbs and holds the vicinity of the outer periphery of the transfer substrate 20. Laser light 111 emitted from a laser irradiation unit 112 can be applied to the transfer substrate 20 held by the transfer substrate holding unit 113 through this opening.

[0031] Furthermore, the transfer substrate holding part 113 is moved relative to the transferred substrate holding part 114 at least in the X-axis direction and the Y-axis direction by a movement mechanism (not shown). A control part controls this movement mechanism to adjust the position of the transfer substrate holding part 113, thereby making it possible to adjust the relative position of the semiconductor chip 1 held on the transfer substrate 20 with respect to the transferred substrate 30.

[0032] The transferred substrate holding part 114 has a flat upper surface, and holds the transferred substrate 30 during the transfer process of the semiconductor chip 1. The transferred substrate holding part 114 has a plurality of suction holes on the upper surface thereof, and holds the back surface of the transferred substrate 30 (the surface on which the semiconductor chip 1 is not transferred) by suction force.

[0033] In the first embodiment, only the transfer substrate holding part 113 moves in the X-axis and Y-axis directions to move the transfer substrate holding part 113 and the transferred substrate holding part 114 relatively, but in cases where the dimensions of the transferred substrate are large and the entire surface of the transferred substrate cannot be positioned directly under the irradiation range of the laser beam 111, the transferred substrate holding part 114 may also be provided with a mechanism for moving in the X-axis and Y-axis directions. Alternatively, neither the transfer substrate holding part 113 nor the transferred substrate holding part 114 may move, and the irradiation position of the laser beam 1111 in the X-axis and Y-axis directions may be controlled by the galvanometer mirror 115 and the fθ lens 116.

[0034] The laser irradiation unit 112 in Example 1 can change the spot size to be irradiated, and can switch between a first laser spot of a size that is wider than the entire area of ​​the semiconductor chip 1 and narrower than the area including half of the adjacent semiconductor chip adjacent to the semiconductor chip 1, and a second laser spot that is smaller than the first laser spot and equal in size to the size of the semiconductor chip 1.

[0035] As a result, since the laser irradiation is performed with a first laser spot that is irradiated to an area wider than the semiconductor chip 1 and narrower than the area including half of the adjacent semiconductor chip adjacent to the semiconductor chip 1, the laser irradiation can be performed on the holding layer adhering the semiconductor chip without high-precision alignment, and since the laser irradiation can be performed with energy PA that can separate the semiconductor chip from the holding layer adhering the semiconductor chip even with laser light having a cross-sectional profile with a Gaussian distribution that does not use a complex optical system, the semiconductor chip can be transferred with high precision with a simple configuration. Also, the adjacent semiconductor chip whose side is not wrapped around by the holding layer can be transferred with high precision with a simple configuration with a second laser spot that is smaller than the first laser spot.

[0036] In the first embodiment, the X direction is the first direction, but this is not necessarily limited to this and can be changed as appropriate. For example, the Y direction may be the first direction, or a diagonal direction between the X direction and the Y direction may be the first direction.

[0037] In the first embodiment, the laser light 111 having the energy PA capable of separating the semiconductor chip 1 from the retention layer 10 is irradiated to an area narrower than the area including the entire semiconductor chip 1 and half of the adjacent semiconductor chip adjacent to the semiconductor chip 1, but this is not necessarily limited to this and can be modified as appropriate. For example, the laser light 111 having the energy PA capable of separating the semiconductor chip 1 from the retention layer 10 may be irradiated to an area of ​​the retention layer 10 wider than the entire semiconductor chip 1, not including the area including the adjacent semiconductor chip.

[0038] (Variation 1) In Modification 1, the region having energy that allows separation from the retention layer by irradiation with laser light 211 is wider than the entire semiconductor chip 1 and narrower than the region of the adjacent semiconductor chip. Modification 1 will be described with reference to Fig. 3. Fig. 3 is a diagram for explaining the laser profile in Modification 1 of the present invention, where (a) shows a cross section of the retention layer and semiconductor chip, and (b) shows the cross-sectional profile of the laser.

[0039] The power of the laser in Modification 1 is smaller than that in Example 1. As shown in Fig. 3, the irradiated laser light 211 has an energy distribution that is maximum at the center of the cross-sectional profile of the first laser spot 50 and becomes weaker the farther in the width direction perpendicular to the irradiation direction, and the region having the energy PA capable of separating from the retention layer 10 is wider than the entire semiconductor chip 1 but narrower than the region of the adjacent semiconductor chip.

[0040] This eliminates the need for highly accurate laser irradiation with a laser spot of the same size as the semiconductor chip, and allows elements such as semiconductor chips to be transferred with high accuracy using a simple configuration.

[0041] (Variation 2) In the cross-sectional profile, the tip of the laser light 311 in the second modification is nearly flat, and has an irradiation range that is wider than the entire area of ​​the semiconductor chip 1 and narrower than the area of ​​the adjacent semiconductor chip. The second modification will be described with reference to Fig. 4. Fig. 4 is a diagram for explaining the cross-sectional profile of the laser in the second modification of the present invention, where (a) shows a cross section of the retention layer and the semiconductor chip, and (b) shows the cross-sectional profile of the laser.

[0042] In the second modification, the irradiation range of the laser light 311 is restricted by a mask to a substantially rectangular shape, and the irradiation range of the energy capable of separating the semiconductor chip 1 is wider than the entire semiconductor chip 1 and narrower than the area of ​​the adjacent semiconductor chip. In the cross-sectional profile of the laser, the tip portion is nearly flat, and has an energy distribution that does not become weaker even with distance in the width direction perpendicular to the irradiation direction, and the area having the energy PA capable of separating the semiconductor chip 1 from the retention layer 10 is wider than the entire semiconductor chip 1 and narrower than the area of ​​the adjacent semiconductor chip.

[0043] In the second modification, a substantially rectangular laser spot is irradiated, but this is not necessarily limited to this and can be modified as appropriate. For example, a substantially circular or elliptical laser spot can be irradiated, and the shape of the laser spot can be made to match the shape of the element.

[0044] This eliminates the need for highly accurate laser irradiation with a laser spot of the same size as the semiconductor chip, and allows elements such as semiconductor chips to be transferred with high accuracy using a simple configuration.

[0045] In the second modification, the region having the energy PA capable of separating from the retention layer 10 is wider than the entire semiconductor chip 1 and narrower than the region of the adjacent semiconductor chip, but this is not necessarily limited to this and can be modified as appropriate. For example, the region having the energy PA capable of separating from the retention layer 10 may be wider than the entire semiconductor chip 1 and have a size that is irradiated to at least a part of the adjacent semiconductor chip adjacent to the semiconductor chip 1, with the tip portion being almost flat in the cross-sectional profile of the laser and having an energy distribution that does not become weaker even with distance in the width direction perpendicular to the irradiation direction.

[0046] (Transfer Method) In the first embodiment, the semiconductor chip 1 arranged in the first direction (X direction) and the second direction (Y direction) on the first main surface 21 of the transfer substrate 20 as shown in Fig. 5 and held by the holding layer 10 is transferred to the transferee substrate 30 by laser lift-off. Laser lift-off refers to a process in which a laser beam 111 is transmitted through the transfer substrate 20 to reach the holding layer 10 between the semiconductor chip 1 and the transfer substrate 20, whereby the polymer of the holding layer 10 is decomposed to generate gas, and the semiconductor chip 1 is biased downward by the generation of this gas. As a result, the semiconductor chip 1 flies downward from the transfer substrate 20 and lands on the transferee substrate 30.

[0047] The transfer substrate 20 is a flat plate made of a material such as SiO2 or sapphire that transmits the laser light 111. The retaining layer 10 is made of an adhesive material such as polyimide, silicon, or dimethylpolysiloxane (PDMS). The transfer substrate 30 can be made of any material such as SiO2, sapphire, glass epoxy, ceramic, or metal.

[0048] A transfer method in Example 1 will be described. A semiconductor chip 1a ("first element" in the claims) arranged on a first main surface 21 of a transfer substrate 20 is irradiated with laser light 111 from a second main surface 22, and the semiconductor chip 1a is transferred to a transfer substrate 30 by laser lift-off. The laser spot of the laser light 111 at this time is a first laser spot 50 having a size that irradiates an area narrower than an area including at least the entire area of ​​one transfer target semiconductor chip 1a, a semiconductor chip 1b ("adjacent element" in the claims) adjacent to the semiconductor chip 1a in the X direction (first direction), and a half of the semiconductor chip 2a adjacent to the semiconductor chip 1a in the Y direction (second direction). In the description of this transfer method, the laser irradiation area is shaped into a substantially rectangular shape by a mask.

[0049] As a result, the laser is irradiated onto the holding layer 10 holding the semiconductor chip 1a from the second main surface 22 of the transfer substrate 20, the exposed holding layer 10 around the semiconductor chip 1a, and the holding layer 10 adhering to the semiconductor chip 1b adjacent in the first direction and the semiconductor chip 2a adjacent in the second direction, in part of the half of the semiconductor chip 1a side, so that the semiconductor chip 1a can be transferred to the transfer substrate 30. At this time, in addition to the holding layer 10 adhering to the semiconductor chip 1b and the half of the semiconductor chip 2a, the holding layer 10 adhering to the end of the semiconductor chip 2b on the semiconductor chip 1a side is also gasified and disappears. This process is called the first element transfer process.

[0050] In this way, in the first element transfer step, since the laser is irradiated with the first laser spot larger than the first semiconductor chip, the laser can be irradiated onto the holding layer to which the semiconductor chip is adhered without high-precision alignment, and the semiconductor chip can be transferred with high precision with a simple configuration. In addition, even if the laser light has a cross-sectional profile with a Gaussian distribution that does not use a complex optical system, the irradiated surface on the holding layer that holds the semiconductor chip can be made almost flat, so the semiconductor chip can be transferred with high precision with a simple configuration.

[0051] After the first element transfer step, a second element transfer step is performed. In the second element transfer step, a semiconductor chip 1c ("second element" in claims) adjacent to the semiconductor chip 1a in the X direction is irradiated with laser light 111 with a size of the first laser spot 50 from a second main surface 22 of the transfer substrate 20 to an area centered on the holding layer 10 holding the semiconductor chip 1c, thereby transferring the semiconductor chip 1c to the transfer substrate 30.

[0052] At this time, the area of ​​the first laser spot 50 centered on the holding layer 10 holding the semiconductor chip 1c is a size that is irradiated to an area narrower than the area including the entire semiconductor chip 1c to be transferred, and the semiconductor chip 1d adjacent to the semiconductor chip 1c in the X direction (first direction) and half of the semiconductor chip 1c side of the semiconductor chip 2c adjacent to the semiconductor chip 1c in the Y direction (second direction).

[0053] In the second element transfer process, the semiconductor chip 1c is transferred to the transfer substrate 30 by laser lift-off, and in addition to the retaining layer 10 adhering to a portion of the above-mentioned half area of ​​the semiconductor chip 1d and the semiconductor chip 2c, the retaining layer 10 adhering to the corner portion of the semiconductor chip 2e on the semiconductor chip 1c side is also gasified and disappears. In this way, in the second element transfer process, the holding layer adhering the second semiconductor chip is also irradiated with laser using a first laser spot larger than the second semiconductor chip, so that the holding layer adhering the semiconductor chip can be irradiated with laser without high-precision alignment, and even if laser light has a cross-sectional profile with a Gaussian distribution that does not use complex optical systems, the holding layer adhering the semiconductor chip can be used as the irradiation surface, so that high-precision transfer of the semiconductor chip can be performed with a simple configuration.

[0054] After the second element transfer process for the semiconductor chip 1c, a second element transfer process is similarly performed for the semiconductor chip 1e (the "second element" in the claims). Furthermore, after that, a second element transfer process is performed for the semiconductor chip 1g (the "second element" in the claims). In the second element transfer process for the semiconductor chips 1e and 1g, similar to the second element transfer process for the semiconductor chip 1c, the first laser spot 50 sequentially irradiates the laser light 111 from the second main surface 22 of the transfer substrate 20 to an area centered on the holding layer 10 holding the semiconductor chips 1e and 1g, thereby sequentially transferring the semiconductor chips 1e and 1g to the transfer substrate 30.

[0055] As a result, the semiconductor chips 1a, 1c, 1e, and 1g that were adhered to the transfer substrate 20 as shown in Figure 5(b) are transferred to the transferred substrate 30, and as shown in Figure 5(c), the semiconductor chip 1b is adhered to the holding layer 11b and held on the transfer substrate 20, the semiconductor chip 1d is adhered to the holding layer 11d and held on the transfer substrate 20, and the semiconductor chip 1f is adhered to the holding layer 11f and held on the transfer substrate 20.

[0056] In the first embodiment, the semiconductor chips 1b, 1d, and 1f correspond to the adjacent elements in the claims, and the semiconductor chips 1c, 1e, and 1g correspond to the second elements in the claims. However, this is not limited to this and can be modified as appropriate. For example, when three semiconductor chips 1a to 1c are arranged in the X direction on the transfer substrate 20, the semiconductor chip 1b corresponds to the adjacent elements in the claims, and the semiconductor chip 1c corresponds to the second elements in the claims. Furthermore, when eight or more semiconductor chips are arranged in the X direction on the transfer substrate 20, the number of adjacent elements and second elements in the claims will be greater than in the first embodiment.

[0057] In the first element transfer step for the semiconductor chip 1a and the second element transfer step for the semiconductor chips 1c, 1e, 1g, the holding layers 11b, 11d, 11f have a part of the half area on the end side of the adhesive surface of the semiconductor chips 1b, 1d, 1f burned away, so that the area to which the semiconductor chips are adhered can be reduced. As a result, the holding layers 11b, 11d, 11f do not wrap around the sides of the semiconductor chips 1b, 1d, 1f, and as described below, the semiconductor chips 1b, 1d, 1f can be transferred by the second laser spot 60, which is smaller than the first laser spot 50 and is equal in size to the semiconductor chips 1b, 1d, 1f.

[0058] Following the first element transferring step and the second element transferring step, the third element transferring step is carried out. In the third element transferring step, as shown in Fig. 6, first, a semiconductor chip 2b (the "third element" in the claims) arranged adjacent to the semiconductor chip 1b (the "adjacent element" in the claims) in the Y direction (second direction) perpendicular to the X direction (first direction) is irradiated with a laser from a second main surface 22 of the transfer substrate 20 to an area centered on the holding layer 10 holding the semiconductor chip 2b, thereby transferring the semiconductor chip 2b to the transfer substrate 30.

[0059] At this time, the area of ​​the first laser spot 50 centered on the holding layer 10 holding the semiconductor chip 2b is an area of ​​a size that is irradiated to the entire semiconductor chip 2b to be transferred, and part of the half of the area on the semiconductor chip 2b side of the semiconductor chips 2a, 2c adjacent to the semiconductor chip 2b in the X direction (first direction) and the semiconductor chips 1b, 3b adjacent to the semiconductor chip 2b in the Y direction (second direction).

[0060] In the third element transfer process, the holding layer to which the third element is adhered is also irradiated with a first laser spot that is larger than the third element. This makes it possible to irradiate the holding layer to which the semiconductor chip is adhered with laser without high-precision alignment. In addition, even if laser light has a cross-sectional profile with a Gaussian distribution that does not use complex optical systems, the holding layer to which the semiconductor chip is adhered can be used as the irradiated surface, making it possible to perform high-precision transfer of the semiconductor chip with a simple configuration.

[0061] Next, in the same manner, the third element transfer step is sequentially performed on the semiconductor chip 2d and the semiconductor chip 2f. That is, the laser beam 111 is sequentially irradiated from the first laser spot 50 onto the semiconductor chip 2d and the holding layer 10 to which the semiconductor chip 2f is adhered, and the semiconductor chip 2d and the semiconductor chip 2f are sequentially transferred onto the transfer substrate 30.

[0062] As a result, the semiconductor chips 2a to 2g that were adhered to the transfer substrate 20 as shown in Figure 6(b) are transferred to the transferred substrate 30 as shown in Figure 6(c), while the semiconductor chip 2a is adhered to the holding layer 12a and held on the transfer substrate 20, the semiconductor chip 2c is adhered to the holding layer 12c and held on the transfer substrate 20, the semiconductor chip 2e is adhered to the holding layer 12e and held on the transfer substrate 20, and the semiconductor chip 2g is adhered to the holding layer 12g and held on the transfer substrate 20.

[0063] Next, as shown in Figure 7, a first element transfer process is performed on the semiconductor chip 3a in the same manner as the first element transfer process on the semiconductor chip 1a, and a second element transfer process is sequentially performed on the semiconductor chips 3c, 3e, and 3g in the same manner as the second element transfer process on the semiconductor chips 1c, 1e, and 1g.

[0064] Then, as shown in FIG. 8, the third element transfer step is sequentially performed on the semiconductor chips 4b, 4d, and 4f in the same manner as the third element transfer step on the semiconductor chips 2b, 2d, and 2f.

[0065] Furthermore, as shown in Figure 9, a first element transfer process is performed on the semiconductor chip 5a in the same manner as the first element transfer process for the semiconductor chip 3a described above, and a second element transfer process is sequentially performed on the semiconductor chips 5c, 5e, and 5g in the same manner as the second element transfer process for the semiconductor chips 3c, 3e, and 3g.

[0066] The semiconductor chips adhesively held on the transfer substrate 20 by the first element transfer step, the second element transfer step, and the third element transfer step remain in a staggered pattern as shown in Fig. 10. Next, the remaining semiconductor chips are transferred. In this case, since the first element transfer step, the second element transfer step, and the third semiconductor chip step have been performed, the holding layers 11b, 11d, and 11f of the semiconductor chips 1b, 1d, and 1f ("adjacent elements" in the claims) lose a part of the peripheral half of the area that adheres the semiconductor chips 1b, 1d, and 1f, and become smaller than the outer shape of the semiconductor chips 1b, 1d, and 1f as shown in Fig. 10(b), and the holding layers do not wrap around the sides of the semiconductor chips 1b, 1d, and 1f.

[0067] Therefore, as shown in Figure 10, an adjacent element transfer process is performed in which a laser is irradiated from the second main surface 22 of the transfer substrate 20 to the holding layer 11b holding the semiconductor chip 1b with a second laser spot 60 that is smaller than the first laser spot 50 and equal to or smaller than the size of the semiconductor chip 1b, thereby transferring the semiconductor chip 1b (the "adjacent element" in the claims) to the transferred substrate 30.

[0068] At this time, as described above, since the retention layer 11b is smaller than the outer shape of the semiconductor chip 1b, even if the second laser spot 60 is smaller than the first laser spot 50 and equal to or smaller than the size of the semiconductor chip 1b, the semiconductor chip 1b can be transferred with high precision without being tilted.

[0069] In the first embodiment, the transfer is performed using the second laser spot 60, which is smaller than the first laser spot 50 and equal to or smaller than the size of the semiconductor chip 1b, but this is not necessarily limited to this and can be modified as appropriate. For example, the transfer may be performed using a laser spot of the same size as the first laser spot 50. In this case, the transfer can be performed with high accuracy even if the accuracy of the laser irradiation is not high as long as the retention layer 11b is included in the laser spot.

[0070] Next, the adjacent element transfer step is sequentially performed on the semiconductor chips 1d and 1f in the same manner as the semiconductor chip 1b, whereby all of the semiconductor chips 1a to 1g are transferred onto the transfer substrate 30, as shown in FIG.

[0071] Next, as shown in Fig. 11, similarly to the adjacent element transfer process for the semiconductor chips 1b, 1d, and 1f described above, an adjacent element transfer process is performed for the semiconductor chips 2a, 2c, 2e, and 2g. As for the semiconductor chips 2a, 2c, 2e, and 2g, a part of the peripheral half area of ​​the holding layer 12a, 12c, 12e, and 12g that adheres the semiconductor chips 2a, 2c, 2e, and 2g disappears by the first element transfer process, the second element transfer process, and the third element transfer process, and as shown in Fig. 11(b), it becomes smaller than the outer shape of the semiconductor chips 2a, 2c, 2e, and 2g. Therefore, it is possible to transfer with high accuracy with the second laser spot 60 that is smaller than the first laser spot 50 and is equal to or smaller than the size of the semiconductor chips 2a, 2c, 2e, and 2g.

[0072] Furthermore, although not shown, the remaining semiconductor chips 3b, 3d, and 3f, semiconductor chips 4a, 4c, 4e, and 4g, and semiconductor chips 5b, 5d, and 5f can be transferred in the same manner as described above by performing an adjacent element transfer process, so that all of the semiconductor chips can be transferred.

[0073] As described above, in the adjacent element transfer process, part of the surrounding half of the retaining layer that holds the semiconductor chip is eliminated, thereby narrowing the area, so that the retaining layer does not wrap around the sides of the semiconductor chip and the semiconductor chip does not tilt during laser lift-off, allowing for precise transfer.

[0074] In the first embodiment, the semiconductor chips arranged in the X direction (first direction) and the Y direction (second direction) are transferred, but this is not necessarily limited to this and can be modified as appropriate. For example, the semiconductor chips arranged only in the X direction may be transferred, or the semiconductor chips arranged only in the Y direction may be transferred. In this case, the third element transfer process is not performed.

[0075] In the first embodiment, the first element, the second element, the third element, and the adjacent element are semiconductor chips, but they are not limited to this and can be changed as appropriate. For example, they can be electronic components such as resistors and capacitors, and materials such as metal pieces.

[0076] In the first embodiment, the elements are transferred to the same substrate, but the present invention is not limited to this and can be modified as appropriate. For example, the elements may be transferred to separate substrates.

[0077] Thus, in the first embodiment, a transfer method for transferring elements arranged at least in a first direction on a first main surface of a transfer substrate and held by a holding layer to a transferee substrate by laser lift-off, comprising: irradiating a laser from a second main surface side of the transfer substrate to an area centered on the holding layer holding the first element to be transferred with a first laser spot having a size that irradiates an area wider than the entire area of ​​at least one first element to be transferred; irradiating the holding layer holding the entire area of ​​the first element to be transferred with a laser with energy capable of separating the first element, and performing a first element transfer step of transferring the first element to the transferee substrate, the method is characterized in that the laser irradiation is performed with a first laser spot wider than the first element, so that the holding layer to which the element is adhered can be irradiated with a laser without performing highly accurate positioning. In addition, even if a laser has a cross-sectional profile of an energy distribution that is maximum at the center of the first laser spot and becomes weaker as it gets farther in the width direction perpendicular to the irradiation direction, a laser with energy capable of separating the element can be irradiated to the entire surface of the holding layer to which the element is adhered, so that an element such as a semiconductor chip can be transferred with high accuracy with a simple configuration.

[0078] Also, a transfer apparatus that transfers elements arranged in at least a first direction on a first main surface of a transfer substrate and held by a holding layer to a transfer substrate by laser lift-off, comprising: A transfer substrate holding unit that holds the transfer substrate; a transfer substrate holding section that holds the transfer substrate substantially parallel to the transfer substrate; a laser irradiation unit capable of irradiating a second main surface of the transfer substrate with a first laser spot having a size that is larger than the entire area of ​​at least one first element to be transferred, the first laser spot being arranged on the transfer substrate via a retention layer, and a second laser spot having a size smaller than the first laser spot; A control unit that switches between the first laser spot and the second laser spot, A transfer device characterized in that when irradiated with the first laser spot, at least the entire area of ​​the first element is irradiated with a laser having energy sufficient to separate the first element from the retention layer, and since laser irradiation is performed with a first laser spot that is wider than the first element, it is possible to irradiate the laser to the retention layer to which the element is adhered without having to perform highly accurate alignment. Furthermore, even if the laser has a cross-sectional profile of energy distribution that is maximum at the center of the first laser spot and weakens as it moves away from the spot in the width direction perpendicular to the irradiation direction, it is possible to irradiate the entire surface of the retention layer that adheres the element with a laser with enough energy to separate the element, thereby enabling elements such as semiconductor chips to be transferred with high precision using a simple configuration. In addition, the second laser spot, which is smaller than the first laser spot, can be used to accurately transfer adjacent elements whose sides are not covered by a retention layer with a simple configuration. EXAMPLES

[0079] Example 2 of the present invention is different from Example 1 in that the first element transfer step is performed on a plurality of first elements. Example 2 will be described with reference to Figs. 12 to 17. Fig. 12 is a diagram for explaining the first element transfer step and the second element transfer step in Example 2 of the present invention, where (a) is a view of the second surface of the transfer substrate, (b) shows the AA' cut surface and shows the state of the semiconductor chip before the laser spot is irradiated, and (c) shows the AA' cut surface and shows the state of the semiconductor chip after the laser spot is irradiated ((a) to (c) are the same as Figs. 13 to 16). Fig. 13 is a diagram for explaining the third element transfer step in Example 2 of the present invention. Fig. 14 is a diagram for explaining another first element transfer step and another second element transfer step in Example 2 of the present invention. Fig. 15 is a diagram for explaining another first element transfer step and another second element transfer step in Example 2 of the present invention. Fig. 16 is a diagram for explaining another first element transfer step in Example 2 of the present invention. Fig. 17 is a diagram for explaining the adjacent element transfer step in Example 2 of the present invention.

[0080] In the second embodiment, first, as shown in Fig. 12, a first element transfer step is performed for a plurality of semiconductor chips 1a, 1b, 2a, 2b ("first elements" in the claims). In the first element transfer step in the second embodiment, a first laser spot 70 having a size for irradiating the entire area of ​​the plurality of first semiconductor chips 1a, 1b, 2a, 2b to be transferred and a part of a half area on the first semiconductor chips 1a, 1b, 2a, 2b side of adjacent semiconductor chips 1c, 2c adjacent to the first semiconductor chips 1a, 1b, 2a, 2b in the X direction (first direction) is irradiated from the second main surface 22 of the transfer substrate 20 to an area centered on the holding layer 10 holding the first semiconductor chips 1a, 1b, 2a, 2b, to transfer the first semiconductor chips 1a, 1b, 2a, 2b to the transfer substrate 30.

[0081] Next, a second element transfer step is performed for the plurality of semiconductor chips 1d, 1e, 2d, 2e ("second elements" in the claims). In the second element transfer step in the second embodiment, a laser is irradiated from a second main surface 22 of a transfer substrate 20 to a region centered on a holding layer 10 holding the second semiconductor chips 1d, 1e, 2d, 2e in the second main surface 22 of a transfer substrate 20 with a first laser spot 70 to the plurality of second semiconductor chips 1d, 1e, 2d, 2e arranged adjacent to the first semiconductor chips 1a, 1b, 2a, 2b on the opposite side to the first semiconductor chips 1a, 1b, 2a, 2b in the adjacent semiconductor chips 1c, 2c adjacent to the first semiconductor chips 1a, 1b, 2a, 2b in the first direction, thereby transferring the second semiconductor chips 1d, 1e, 2d, 2e to a transfer substrate 30.

[0082] Next, a second element transfer step is performed for the semiconductor chips 1g and 2g. As a result, as shown in Fig. 12(c), among the semiconductor chips 1a to 1g, the semiconductor chips 1a, 1b, 1d, 1e, and 1g are transferred to the transfer substrate 30, and the semiconductor chips 1c and 1f are adhered to the transfer substrate 20 by the retaining layers 11c and 11f, respectively. At this time, the retaining layers 11c and 11f are smaller than the outer shape of the semiconductor chips 1c and 1f, as shown in Fig. 12(c), because a part of the periphery adhering the semiconductor chips 1c and 1f has disappeared due to the first element transfer step and the second element transfer step already performed.

[0083] Although not shown, among the semiconductor chips 2a to 2g, the semiconductor chips 2a, 2b, 2d, 2e, and 2g are transferred to the transferred substrate 30, and the semiconductor chips 2c and 2f are adhered to the transfer substrate 20 by the holding layers 11c and 11f, respectively. The holding layers 12c and 12f (not shown) that adhesively hold the semiconductor chips 2c and 2f have lost a part of the periphery that adheres the semiconductor chips 2c and 2f due to the first element transfer step and the second element transfer step that have already been performed, and are therefore smaller than the outer shape of the semiconductor chips 2c and 2f.

[0084] 13, a third element transfer process for the semiconductor chip 2c (the "third semiconductor chip" in the claims) and a third element transfer process for the semiconductor chip 2f (the "third semiconductor chip" in the claims) are sequentially performed. As a result, all of the semiconductor chips 2a to 2g are transferred to the transfer substrate 30.

[0085] Furthermore, as shown in Fig. 14, a first semiconductor transfer process is carried out for the semiconductor chips 3a, 3b, 4a, and 4b. Thereafter, a second semiconductor transfer process is carried out for the semiconductor chips 3e, 4d, and 4e, and a second semiconductor transfer process is carried out for the semiconductor chip 4g. As a result, as shown in Fig. 14(c), all of the semiconductor chips 3a to 3g are transferred onto the transfer substrate 30. Although not shown, the semiconductor chips 4a, 4b, 4d, 4e, and 4g are also transferred onto the transfer substrate 30.

[0086] Next, as shown in Fig. 15, a first element transfer process is carried out for the semiconductor chips 5a and 5b. After that, a second element transfer process is carried out for the semiconductor chips 5d and 5e, and a second element transfer process is carried out for the semiconductor chip 5g. As a result, as shown in Fig. 15(c), the semiconductor chips 5a, 5b, 5d, 5e, and 5g are transferred to the transfer substrate 30, and the semiconductor chips 5c and 5f are adhesively held to the transfer substrate 20 via the holding layers 15c and 15f.

[0087] At this time, since the first element transfer process and the second element transfer process have already been carried out on the retaining layers 15c, 15f, part of the periphery of the retaining layers 15c, 15f that adhere the semiconductor chips 5c, 5f has disappeared, and the retaining layers 15c, 15f are smaller than the outer shape of the semiconductor chips 5c, 5f, as shown in Figure 15(c).

[0088] 16, a first element transfer step is sequentially performed on the semiconductor chips 4c, 5c and the semiconductor chips 4f, 5f. As a result, all of the semiconductor chips 4a to 4g, 5a to 5g are transferred to the transfer substrate 30. At this time, the holding layers 14c, 14f, 15c, 15f adhering the conductor chips 4c, 5c, 4f, 5f all lose a part of their periphery and become smaller than the outer shape of the semiconductor chips 4c, 5c, 4f, 5f. Therefore, as in the adjacent element transfer step described later, the transfer can be performed with high accuracy even if a second laser spot smaller than the first laser spot is used.

[0089] Finally, as shown in Fig. 17, an adjacent element transfer process for semiconductor chip 1c (the "adjacent element" in the claims) and an adjacent element transfer process for semiconductor chip 1f (the "adjacent element" in the claims) are performed. The second laser spot 80 in the adjacent element transfer process in Example 5 has the same laser spot size as the second laser spot 60 in Example 1.

[0090] Also in the second embodiment, in the adjacent element transfer process, the ends of the retaining layer holding the semiconductor chip disappear, narrowing the area, so that the retaining layer does not wrap around the sides of the semiconductor chip. This prevents the semiconductor chip from tilting during laser lift-off, and enables accurate transfer even with a laser spot 80 that is equal to or smaller than the size of the semiconductor chip.

[0091] Thus, in the second embodiment, a transfer method for transferring elements arranged at least in a first direction on a first main surface of a transfer substrate and held by a holding layer to a transferee substrate by laser lift-off includes irradiating a laser from a second main surface side of the transfer substrate to an area centered on the holding layer holding the first element to be transferred with a first laser spot having a size that irradiates an area wider than the entire area of ​​at least one first element to be transferred, and irradiating the holding layer holding the entire area of ​​the first element to be transferred with a laser with energy capable of separating the first element, and performing a first element transfer step of transferring the first element to the transferee substrate. Since the laser irradiation is performed with a first laser spot wider than the first element, the holding layer to which the element is adhered can be irradiated with a laser without performing highly accurate positioning. In addition, even if a laser has a cross-sectional profile of an energy distribution that is maximum at the center of the first laser spot and becomes weaker as it gets farther in the width direction perpendicular to the irradiation direction, a laser with energy capable of separating the element can be irradiated to the entire surface of the holding layer to which the element is adhered, so that an element such as a semiconductor chip can be transferred with high accuracy with a simple configuration.

[0092] Also, a transfer apparatus that transfers elements arranged in at least a first direction on a first main surface of a transfer substrate and held by a holding layer to a transfer substrate by laser lift-off, comprising: A transfer substrate holding unit that holds the transfer substrate; a transfer substrate holding section that holds the transfer substrate substantially parallel to the transfer substrate; a laser irradiation unit capable of irradiating a second main surface of the transfer substrate with a first laser spot having a size that is larger than the entire area of ​​at least one first element to be transferred, the first laser spot being arranged on the transfer substrate via a retention layer, and a second laser spot having a size smaller than the first laser spot; A control unit that switches between the first laser spot and the second laser spot, A transfer device characterized in that when irradiated with the first laser spot, at least the entire area of ​​the first element is irradiated with a laser having energy sufficient to separate the first element from the retention layer, and since laser irradiation is performed with a first laser spot that is wider than the first element, it is possible to irradiate the laser to the retention layer to which the element is adhered without having to perform highly accurate alignment. Furthermore, even if the laser has a cross-sectional profile of energy distribution that is maximum at the center of the first laser spot and weakens as it moves away from the spot in the width direction perpendicular to the irradiation direction, it is possible to irradiate the entire surface of the retention layer that adheres the element with a laser with enough energy to separate the element, thereby enabling elements such as semiconductor chips to be transferred with high precision using a simple configuration. In addition, the second laser spot, which is smaller than the first laser spot, can be used to accurately transfer adjacent elements whose sides are not covered by a retention layer with a simple configuration. [Industrial Applicability]

[0093] The transfer method and transfer device of the present invention can be widely used in the field of transferring and mounting elements such as semiconductor chips. [Explanation of symbols]

[0094] 1(1a, 1b, 1c, 1d, 1e, 1f, 1g): Semiconductor chip 2(2a, 2b, 2c, 2d, 2e, 2f, 2g): Semiconductor chip 3(3a, 3b, 3c, 3d, 3e, 3f, 3g): Semiconductor chip 4(4a, 4b, 4c, 4d, 4e, 4f, 4g): Semiconductor chip 5(5a, 5b, 5c, 5d, 5e, 5f, 5g): Semiconductor chip 10: Holding layer 11(11a, 11b, 11c, 11d, 11e, 11f, 11g): Holding layer 12(12a, 12b, 12c, 12d, 12e, 12f, 12g): Holding layer 13(13a, 13b, 13c, 13d, 13e, 13f, 13g): Holding layer 14(14a, 14b, 14c, 14d, 14e, 14f, 14g): Holding layer 15(15a, 15b, 15c, 15d, 15e, 15f, 15g): Holding layer 20: Transfer substrate 21: First main surface 22: Second main surface 30: Substrate to be transferred 50: First laser spot 60: Second laser spot 70: First laser spot 80: Second laser spot 100: Transfer device 110: Transfer section 111: Laser light 112: Laser irradiation section 113: Transfer substrate holding section 114: Substrate to be transferred holding section 115: Galvano mirror 116 fθ lens 211: Laser light 311: Laser light

Claims

1. A transfer method for transferring elements arranged in at least a first direction on a first main surface of a transfer substrate and held by a holding layer to a transfer substrate by laser lift-off, comprising: irradiating the holding layer with a laser from the second main surface side of the transfer substrate, the holding layer being centered on an area holding the first element to be transferred, with a first laser spot having a size that allows the holding layer to be irradiated with a region wider than the entire area of ​​at least one first element to be transferred; a first element transferring step is carried out in which the holding layer holding the entire area of ​​the first element to be transferred is irradiated with a laser having energy capable of separating the first element, and the first element to be transferred is transferred to a transfer substrate; A transfer method characterized in that a region having energy capable of separating the first element from the retention layer is larger than the entire area of ​​the first element and is large enough to include a portion of the half of the first element side of an adjacent element adjacent to the first element.

2. 2. The transfer method according to claim 1, wherein the first laser spot has an energy distribution that is maximum at the center of the cross-sectional profile and becomes weaker with increasing distance in a width direction perpendicular to the irradiation direction.

3. After the first element transfer step, The transfer method according to claim 1 or 2, characterized in that a second element transfer step is carried out, in which a laser is irradiated from the second main surface side of the transfer substrate to an area centered on the holding layer that holds the second element, using the first laser spot, to at least one second element that is adjacent to the first element and arranged on the opposite side of the first element in an adjacent element adjacent to the first element, thereby transferring the second element to a transferred substrate.

4. The transfer substrate has elements arranged and held via a holding layer in a second direction perpendicular to the first direction, After the second element transfer step, The transfer method according to claim 3, characterized in that a third element transfer process is carried out, in which a third element arranged adjacent to the adjacent element in the second direction is transferred to a transfer substrate by irradiating a laser from the second main surface side of the transfer substrate to an area centered on the holding layer that holds the third element with the first laser spot.

5. After the third element transfer step, The transfer method according to claim 4, further comprising the step of: irradiating the holding layer holding the adjacent element from the second main surface side of the transfer substrate with a laser using the first laser spot or a second laser spot smaller than the first laser spot to transfer the adjacent element to a transfer substrate.

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