Method and apparatus for transferring this element

Abstract

The present invention provides an element transfer method and an element transfer apparatus that enable the transfer of elements while suppressing element damage. [Solution] This semiconductor chip transfer method comprises a laser beam shaping step of shaping a laser beam L into a linear or arc shape, and a laser beam irradiation step of irradiating a single semiconductor chip 1 with the laser beam L multiple times. The laser beam shaping step includes shaping the laser beam L into a linear or arc shape so that the boundary portion where the semiconductor chip 1 peels off from the support substrate 10, generated each time the laser beam L is irradiated, is linear or arc shape. The laser beam irradiation step includes irradiating a single semiconductor chip 1 multiple times with the laser beam L, which has been shaped into a linear or arc shape by the laser beam shaping step, while moving it relative to the support substrate 10 from one end of the semiconductor chip 1 to the other end, thereby peeling the semiconductor chip 1 off from the support substrate 10 at the irradiation position of the laser beam L.

Description

Technical Field

[0001] This invention relates to an element transfer method and an element transfer apparatus including a laser light oscillation unit that oscillates laser light.

Background Art

[0002] Conventionally, an element transfer method including a laser light oscillation unit that oscillates laser light has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses an element transfer method for transferring (lifting) an object attached to a donor substrate onto a receptor substrate. In Patent Document 1, the donor substrate and the receptor substrate are arranged to face each other. Further, the donor substrate is arranged above the receptor substrate. The object is attached to the lower surface of the donor substrate. An optical absorption layer is provided between the donor substrate and the object. In Patent Document 1, laser light is irradiated from a laser device arranged above the donor substrate toward the object attached to the donor substrate. Thereby, the optical absorption layer is ablated by the laser light transmitted through the donor substrate, and the object is transferred (lifted) onto the receptor substrate. Further, in Patent Document 1, laser light having a spot region substantially the same size as the object is irradiated onto the object. Thereby, the object is transferred onto the receptor substrate by one irradiation of laser light.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the above-mentioned Patent Document 1, since one object is transferred to the receptor substrate with a single laser beam irradiation, the spot area irradiated by the laser beam onto the object is approximately the same as the size of the object. Therefore, in the above-mentioned Patent Document 1, the range of laser beam irradiation is relatively large relative to the size of the object with a fine structure, and the impact on the object caused by the ablation of the light-absorbing layer by the laser beam (stress applied to the object from the support substrate side) and the bending deformation of the object due to the expansion deformation of the light-absorbing layer due to laser beam irradiation may exceed the physical strength of the object with a fine structure. Consequently, in the method described in the above-mentioned Patent Document 1, one object is transferred to the receptor substrate with a single laser beam irradiation, the object (element) may be damaged. For this reason, an element transfer method that transfers elements while suppressing element damage is desired.

[0006] This invention was made to solve the above-mentioned problems, and one of its objectives is to provide an element transfer method and an element transfer apparatus that can transfer elements while suppressing element damage. [Means for solving the problem]

[0007] To achieve the above objective, the element transfer method according to this first aspect comprises a laser beam shaping step of shaping laser light into a linear or arc shape, and a laser beam irradiation step of irradiating a single element multiple times with laser light from the side opposite to the surface on which the support substrate supports the element, toward the support substrate on which the element is supported, wherein the laser beam shaping step includes shaping the laser light into a linear or arc shape such that the boundary portion where the element peels off from the support substrate, generated each time the laser light is irradiated, is linear or arc shape, and the laser beam irradiation step includes irradiating a single element multiple times with the laser light shaped into a linear or arc shape by the laser beam shaping step, while moving relative to the support substrate from one end of the element toward the other end of the element when viewed from a direction perpendicular to the surface of the support substrate, thereby peeling the element off from the support substrate at the laser beam irradiation position.

[0008] In this first phase of element transfer, as described above, the laser beam shaping step includes shaping the laser beam into a linear or arc shape so that the boundary portion where the element detaches from the support substrate is linear or arc-shaped each time the laser beam is irradiated. The laser beam irradiation step includes irradiating a single element multiple times with the laser beam shaped into a linear or arc shape by the laser beam shaping step, while moving relative to the support substrate from one end to the other, viewed from a direction perpendicular to the surface of the support substrate. As a result, the element is irradiated with laser beam multiple times to detach it from the support substrate. By irradiating with laser beam in multiple stages, the spot area of ​​the laser beam irradiated onto the element to detach it from the support substrate can be made smaller compared to when the laser beam is irradiated once. As a result, the impact on the element caused by laser ablation and the bending deformation of the object caused by laser irradiation can be suppressed so as not to exceed the physical strength of the element. Here, a case where the boundary portion where the element detaches from the support substrate is not linear or arc-shaped is when it may be stepped or curved in multiple directions. In parts of the element corresponding to the corners of the stepped boundary portion or the inflection points of the curve, the shape of the boundary portion where the element detaches from the support substrate changes significantly, causing stress concentration and higher stress than the surrounding parts. Therefore, in the first curved surface element transfer method, by keeping the boundary portion where the element detaches from the support substrate linear or arc-shaped, it is possible to eliminate parts where the shape of the boundary portion where the element detaches from the support substrate changes significantly, thereby suppressing localized stress concentration from the support substrate to the element. This makes it possible to suppress localized large shocks from laser beam irradiation on the element. In addition, if the boundary portion where the element detaches from the support substrate is parallel to the crystal orientation of the single-crystal silicon that constitutes the element, the silicon is prone to fracture, and the element may be damaged.In the first phase of the element transfer method, by making the boundary portion where the element peels off from the support substrate arc-shaped, it is possible to prevent the boundary portion where the element peels off from the support substrate from being parallel to the crystal orientation of the single-crystal silicon that constitutes the element. As a result, it is possible to provide an element transfer method that can transfer the element while further suppressing damage to the element.

[0009] In the element transfer method according to the first aspect described above, preferably, the laser beam shaping step includes a step of shaping the laser beam in the laser beam shaping step into a plurality of dot-shaped laser beams arranged in a straight line or arc, such that the boundary portion where the element is peeled off from the support substrate each time the laser beam is irradiated is in a straight line or arc, and the laser beam irradiation step includes a step of irradiating a single element multiple times with the plurality of dot-shaped laser beams while moving relative to the support substrate from one end of the element to the other end. With this configuration, a plurality of dot-shaped laser beams arranged in a straight line or arc are irradiated multiple times while moving relative to the support substrate from one end of the element to the other end. As a result, a plurality of dot-shaped laser beams are irradiated onto the support substrate. Here, when a line-shaped laser beam is irradiated onto the support substrate, the spot area of ​​the laser beam is continuous in a line on the support substrate, so the irradiation energy of the laser beam received by the support substrate becomes large, and the force that the laser beam exerts to peel the element off the support substrate may become excessive. Therefore, by irradiating the support substrate with multiple dot-shaped laser beams, the spot regions of the multiple dot-shaped laser beams can be arranged at intervals that ensure the minimum force required for the laser beams to detach the element from the support substrate. As a result, the impact on the element caused by laser ablation and the bending deformation of the object caused by laser irradiation can be minimized.

[0010] In this case, preferably, the laser beam forming step includes a step of forming the laser beam in the laser beam forming step into a plurality of dot-shaped laser beams arranged in a straight line or arc, such that the boundary portion where the element is peeled off from the support substrate each time the laser beam is irradiated is in a straight line or arc shape from one side of the rectangular element to another side different from that one side, and the laser beam irradiation step includes a step of simultaneously irradiating a single element with a plurality of dot-shaped laser beams. With this configuration, since a plurality of dot-shaped laser beams are irradiated onto a single element simultaneously, the peeling time of the element can be shortened compared to when multiple dot-shaped laser beams are irradiated sequentially.

[0011] In the element transfer method according to the first aspect described above, preferably, the laser beam forming step includes a step of changing the number of multiple laser beams arranged in a straight line or arc according to the length of the boundary portion where the element peels off from the support substrate each time the laser beam is irradiated, and the laser beam irradiation step includes a step of irradiating a rectangular element with laser beam from one corner toward the other corner opposite to the first corner, while changing the number of multiple laser beams arranged in a straight line or arc according to the length of the boundary portion where the element peels off from the support substrate. Here, in the method of adjusting the shape (length) of the laser beam by the opening of the mask through which the laser beam passes, the shape (length) of the laser beam cannot be adjusted unless the mask is changed to one with a different opening size, so adjusting the shape (length) of the laser beam is time-consuming and laborious. In the laser beam irradiation step, the shape (length) of the laser beam can be adjusted by changing the number of multiple laser beams arranged in a straight line or arc. This eliminates the need to change the mask to one with a different opening size when adjusting the shape (length) of the laser beam. As a result, it becomes easier to adjust the shape (length) of the laser beam according to the length of the boundary portion where the element peels off from the support substrate.

[0012] The element transfer apparatus according to this second phase comprises a laser beam shaping unit that shapes laser light into a linear or arc shape, and a laser beam irradiation unit that irradiates a single element multiple times with laser light from the side opposite to the surface on which the support substrate supports the element, toward the support substrate on which the element is supported. The laser beam shaping unit shapes the laser light into a linear or arc shape so that the boundary portion where the element peels off from the support substrate each time the laser light is irradiated is linear or arc shape. The laser beam irradiation unit is configured to irradiate a single element multiple times with the laser light shaped into a linear or arc shape by the laser beam shaping unit, while moving relative to the support substrate from one end of the element toward the other end, when viewed from a direction perpendicular to the surface of the support substrate.

[0013] In this second phase of the element transfer apparatus, as described above, the laser beam shaping unit shapes the laser beam into a straight line or arc shape so that the boundary portion where the element detaches from the support substrate is straight or arc-shaped each time the laser beam is irradiated. The laser beam irradiation unit irradiates a single element multiple times with the laser beam shaped into a straight line or arc shape by the laser beam shaping unit, moving relative to the support substrate from one end of the element to the other end, viewed from a direction perpendicular to the surface of the support substrate. As a result, the element is irradiated with laser beam multiple times to detach it from the support substrate. By irradiating with laser beam in multiple passes, the spot area of ​​the laser beam irradiated onto the element to detach it from the support substrate can be made smaller compared to when the laser beam is irradiated once. As a result, the impact on the element caused by laser ablation and the bending deformation of the object caused by laser irradiation can be suppressed so as not to exceed the physical strength of the element. Here, a case in which the boundary portion where the element detaches from the support substrate is not straight or arc-shaped is when the boundary portion where the element detaches from the support substrate is stepped or curved in multiple directions. In the second-formed element transfer apparatus, stress concentrates in parts of the element corresponding to stepped corners at the boundary where the element detaches from the support substrate, or in parts corresponding to inflection points of curves, because the shape of the boundary where the element detaches from the support substrate changes significantly, resulting in higher stress than the surrounding areas. Therefore, in the second-formed element transfer apparatus, by keeping the boundary where the element detaches from the support substrate straight or curved, it is possible to eliminate areas where the shape of the boundary where the element detaches from the support substrate changes significantly, thereby suppressing localized stress concentration on the element from the support substrate. This suppresses the localized large impact of laser beam irradiation on the element. Furthermore, if the boundary where the element detaches from the support substrate is parallel to the crystal orientation of the single-crystal silicon that constitutes the element, the silicon is prone to fracture, and the element may be damaged. In the second-formed element transfer apparatus, by making the boundary where the element detaches from the support substrate curved, it is possible to prevent the boundary where the element detaches from the support substrate from being parallel to the crystal orientation of the single-crystal silicon that constitutes the element.As a result, the element can be transferred while further suppressing element damage. [Effects of the Invention]

[0014] According to the present invention, as described above, it is possible to provide an element transfer method and an element transfer apparatus that can transfer elements while suppressing element damage. [Brief explanation of the drawing]

[0015] [Figure 1] This is a schematic diagram showing the overall configuration of a semiconductor chip transfer apparatus according to the first to fifth embodiments. [Figure 2] This is a schematic diagram showing a configuration in which a semiconductor chip is supported on a support substrate. [Figure 3] This is a side view of a semiconductor chip transfer apparatus according to the first to fifth embodiments. [Figure 4] This is a flowchart illustrating the processing steps of the semiconductor chip transfer method according to the first to fifth embodiments. [Figure 5] This figure shows the irradiation position of the laser beam when peeling a semiconductor chip according to the first embodiment from one end to the other end of the support substrate. [Figure 6] This figure shows the laser beam irradiation position when peeling a semiconductor chip from the support substrate from one end to the other, according to a comparative example. [Figure 7] This figure shows the irradiation position of the laser beam when peeling a semiconductor chip from one side to the other side according to the second embodiment. [Figure 8] This figure shows the laser beam irradiation position when peeling a semiconductor chip from one side to the other using a comparative example. [Figure 9] This figure shows the laser beam irradiation position when the boundary portion where the semiconductor chip, generated each time laser light is irradiated, peels off from the support substrate is arc-shaped according to the third embodiment. [Figure 10]This is a diagram for explaining the length of the boundary portion where the square semiconductor chip generated each time laser light is irradiated according to the fourth embodiment peels off from the support substrate. [Figure 11] This is a diagram for explaining the length of the boundary portion where the rectangular semiconductor chip generated each time laser light is irradiated according to the fifth embodiment peels off from the support substrate.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, embodiments embodying the present invention will be described based on the drawings.

[0017] [First Embodiment] The semiconductor chip transfer device 100 according to the first embodiment will be described. Note that the semiconductor chip transfer device 100 is an example of the "element transfer device" in the claims. Also, the semiconductor chip 1 is an example of the "element" in the claims.

[0018] (Semiconductor Chip Transfer Device) As shown in FIG. 1, the semiconductor chip transfer device 100 is configured to transfer the semiconductor chip 1 supported on the support substrate 10 to the transfer target substrate 20 by the laser lift-off method.

[0019] The semiconductor chip transfer device 100 includes a support substrate holding portion 30, a transfer target substrate holding portion 40, a moving mechanism 50, a control portion 60, and a laser light output portion 70. In the drawings, the left-right direction (one direction in the horizontal plane) of the semiconductor chip transfer device 100 is defined as the X direction. Also, the up-down direction (vertical direction) of the semiconductor chip transfer device 100 is defined as the Z direction. Further, the upward direction is the Z1 direction, and the downward direction is the Z2 direction. Also, the direction orthogonal to the X direction and the Z direction of the semiconductor chip transfer device 100 (the other direction in the horizontal plane) is defined as the Y direction.

[0020] As shown in Figure 2, the semiconductor chip 1 is a thin, rectangular element with sides of approximately several hundred micrometers to tens of millimeters, such as a memory chip. Note that the semiconductor chip 1 is not limited to thin elements like memory chips, but may be other types of semiconductor elements. Furthermore, multiple semiconductor chips 1 are arranged on the support substrate 10. The pitch between multiple semiconductor chips 1 is relatively small. For example, if the semiconductor chip 1 has a rectangular shape, the pitch between multiple semiconductor chips 1 is smaller than the length of the side of the semiconductor chip 1 along the Y direction.

[0021] As shown in Figure 3, the support substrate 10 is formed from a material that transmits laser light L, such as an SiO2 (silicon dioxide) substrate or a sapphire substrate. The support substrate 10 supports the semiconductor chip 1 via an adhesive layer 2. The support substrate 10 also supports multiple semiconductor chips 1 via the adhesive layer 2. The adhesive layer 2 is also called a transfer material.

[0022] The adhesive layer 2 is located on the Z2-side surface 10a of the support substrate 10. Multiple semiconductor chips 1 are held on the Z2-side surface 2a of the adhesive layer 2. As shown in Figure 2, the multiple semiconductor chips 1 are arranged in a matrix at predetermined intervals on the support substrate 10 via the adhesive layer 2. The support substrate 10 has a circular shape. The adhesive layer 2 is made of a material that decomposes and generates gas components when irradiated with laser light L from the laser light irradiation unit 90 of the laser light output unit 70. By generating gas components, the adhesive layer 2 deforms into a convex shape that protrudes toward the Z2 side. For example, polyimide or silicon can be used as the adhesive layer 2.

[0023] As shown in Figure 1, the support substrate holder 30 holds the support substrate 10 on which the semiconductor chip 1 is supported. The support substrate holder 30 holds the support substrate 10 with the semiconductor chip 1 supported, with the surface 10a (see Figure 3) supporting the semiconductor chip 1 facing downwards. The support substrate holder 30 has an opening 31. Laser light L emitted from the laser light irradiation unit 90 of the laser light output unit 70 is irradiated onto the support substrate 10 held by the support substrate holder 30 through the opening 31. The support substrate holder 30 is configured to be able to move relative to the transfer substrate holder 40 in at least the X and Y directions by a moving mechanism 50.

[0024] As shown in Figure 3, the transfer substrate 20 is a substrate for manufacturing semiconductor products, for example, by transferring a large number of semiconductor chips 1 from a support substrate 10 onto the transfer substrate 20. The transfer substrate 20 has an adhesive layer 21 formed thereon for bonding the transferred semiconductor chips 1. The adhesive layer 21 is also called a catch layer. The transfer substrate 20 may also have wiring formed thereon that can be electrically connected to the transferred semiconductor chips 1. The transfer substrate 20 has a rectangular shape.

[0025] The substrate holding unit 40 holds the substrate 20 on which the semiconductor chip 1, supported by the support substrate 10, is transferred, from below (Z2 side).

[0026] As shown in Figure 1, the moving mechanism 50 moves the support substrate 10 and the substrate to be transferred holding part 40 relative to each other. Specifically, the moving mechanism 50 moves the support substrate holding part 30 and the substrate to be transferred holding part 40 individually. The moving mechanism 50 moves the support substrate holding part 30 and the substrate to be transferred holding part 40 relative to each other in at least the X and Y directions. Note that the moving mechanism 50 may move the support substrate holding part 30 without moving the substrate to be transferred holding part 40. The relative movement of the support substrate holding part 30 and the substrate to be transferred holding part 40 by the moving mechanism 50 makes it possible to adjust the relative position of the semiconductor chip 1 placed in the support substrate 10 with respect to the substrate to be transferred 20.

[0027] The control unit 60 includes, for example, a processor such as a CPU (Central Processing Unit) and memory such as ROM (Read Only Memory) and RAM (Random Access Memory), and performs various controls by executing a program (software). Alternatively, the control unit 60 may be configured by hardware, with a dedicated processor (processing circuit). The control unit 60 arbitrarily selects a semiconductor chip 1 within the transfer area and controls the detachment of the selected semiconductor chip 1 from the support substrate 10 and transfer it to the transfer substrate 20 by irradiating the laser light output unit 70 with laser light L. The control unit 60 also controls the operation of the moving mechanism 50.

[0028] The laser light output unit 70 includes a laser light oscillation unit 71, a laser light shaping unit 80, and a laser light irradiation unit 90.

[0029] The laser light oscillator 71 is positioned on the opposite side of the surface 10a of the support substrate 10 that supports the semiconductor chip 1, and emits laser light L toward the support substrate 10. The laser light oscillator 71 emits either a pulsed laser or a CW laser.

[0030] The laser light shaping unit 80 includes an optical system 81 that shapes the laser light L emitted from the laser light oscillation unit 71 into a line shape, and a GLV (Grating Light Valve: registered trademark) 82 that shapes the line-shaped laser light L into multiple dot-shaped laser light L. The GLV 82 is a spatial light modulator in which thousands of fine structures of silicon nitride film called "ribbons" are formed on a silicon chip. By electrically controlling the deflection of the ribbons, the GLV 82 functions as a diffraction grating. In addition to the GLV 82, a Planar Light Valve (PLV) or LCOS-SLM can also be used.

[0031] The laser beam irradiation unit 90 includes a mirror 91 and a projection lens 92. The mirror 91 bends the direction of propagation of the laser beam L toward the support substrate 10. For example, the mirror 91 bends the laser beam L traveling in the X1 direction toward the Z2 direction. The projection lens 92 focuses the laser beam L from the mirror 91 onto the transfer area of ​​the support substrate 10. That is, the projection lens 92 reduces the laser beam L and projects it onto the support substrate 10.

[0032] As shown in Figure 3, the control unit 60 controls the irradiation position of the laser beam L so that, when viewed from a direction perpendicular to the surface of the support substrate 10 (Z direction), the laser beam L moves relative to the support substrate 10 and is irradiated from one end 1a to the other end 1b of the semiconductor chip 1. The laser beam output unit 70 irradiates the laser beam L to the surface 10b of the support substrate 10, which is held by the support substrate holding unit 30, opposite to the surface 10a that supports the semiconductor chip 1, via the mirror 91 and the projection lens 92. When the laser beam L is irradiated onto the adhesive layer 2 via the support substrate 10, the semiconductor chip 1 is peeled off from the support substrate 10 and transferred from the support substrate 10 to the transfer substrate 20. In other words, a transfer is performed by the laser lift-off method. Note that surface 10b of the support substrate 10 is an example of a "surface" in the claims.

[0033] (Semiconductor chip transfer method) Next, the semiconductor chip transfer method will be described with reference to Figure 4. Note that the semiconductor chip transfer method is an example of the "device transfer method" described in the patent claims.

[0034] In step S1, the control unit 60 selects the semiconductor chip 1 to be transferred, which is supported on the support substrate 10. The control unit 60 then controls the moving mechanism 50 so that the selected semiconductor chip 1 is irradiated with laser light L. As a result, the positions of the support substrate holding portion 30 and the transfer substrate holding portion 40 are changed so that the selected semiconductor chip 1 is irradiated with laser light L.

[0035] In step S2, the control unit 60 controls the laser light oscillation unit 71 so that the laser light L is irradiated toward the support substrate 10 on which the semiconductor chip 1 is supported via the adhesive layer 2. The laser light L emitted from the laser light oscillation unit 71 is formed into a line shape by the optical system 81, and the GLV 82 forms the line-shaped laser light L into a plurality of dot-shaped laser light L (laser light shaping process). The control unit 60 also controls the position of the support substrate 10 so that the laser light L moves relative to the support substrate 10 and irradiates it multiple times, from one end 1a to the other end 1b of the semiconductor chip 1, when viewed from a direction perpendicular to the surface 10b of the support substrate 10 (laser light irradiation process). Specifically, the control unit 60 controls the movement mechanism 50 to move the support substrate 10 so that the laser light L moves relative to the support substrate 10 and irradiates it multiple times.

[0036] In the first embodiment, as shown in Figure 5, the laser irradiation step includes irradiating a single semiconductor chip 1 multiple times with a laser beam L that has been formed in a straight or arc shape by the laser beam shaping step, while moving relative to the support substrate 10 from one end 1a to the other end 1b of the semiconductor chip 1 when viewed from a direction perpendicular to the surface of the support substrate 10, thereby peeling the semiconductor chip 1 from the support substrate 10 at the irradiation position of the laser beam L.

[0037] Furthermore, in the first embodiment, the laser beam forming process includes a step of forming the laser beam L in the laser beam forming process into a plurality of dot-shaped laser beams L arranged in a straight line, such that the boundary portion (peeling boundary portion) 95 where the semiconductor chip 1 peels off from the support substrate 10, which is generated each time the laser beam L is irradiated, is linear.The laser beam irradiation process includes a step of irradiating a single semiconductor chip 1 multiple times with the plurality of dot-shaped laser beams L while moving relative to the support substrate 10 from one end 1a to the other end 1b of the semiconductor chip 1.Specifically, in the first embodiment, as shown in Figure 5, the laser beam L is irradiated multiple times on a single semiconductor chip 1 while moving (scanning) relative to the support substrate 10 from one end 1a to the other end 1b of the semiconductor chip 1 when viewed from a direction perpendicular to the surface of the support substrate 10 (Z direction).At this time, the laser beam L irradiated while scanning, such as the first irradiation position P1, the second irradiation position P2, and the third irradiation position P3, on the semiconductor chip 1 is composed of a plurality of dot-shaped laser beams L. In this case, the delamination boundary portion 95, which is generated each time multiple dot-shaped laser beams L are irradiated, is linear.

[0038] Next, in step S3, the control unit 60 determines whether the entire semiconductor chip 1 to be transferred has been transferred. If the result in step S3 is Yes, the semiconductor chip transfer method flow ends. If the result in step S3 is No, the process returns to step S1.

[0039] (Comparison with comparative example) Next, we will explain a comparison between the laser irradiation position when peeling a semiconductor chip from the support substrate from one end to the other according to the first embodiment, and the laser irradiation position when peeling a semiconductor chip from the support substrate from one end to the other according to the comparative example.

[0040] In the first embodiment, as shown in Figure 5, the laser beam L irradiated onto the semiconductor chip 1 while scanning is composed of multiple dot-shaped laser beams L, at the first irradiation position P1, the second irradiation position P2, and the third irradiation position P3. In this case, the delamination boundary portion 95 is linear. On the other hand, in the comparative example, as shown in Figure 6, the laser beam is irradiated onto the semiconductor chip 1 while scanning from one end to the other, at the first irradiation position P1, the second irradiation position P2, and the third irradiation position P3. In this case, the delamination boundary portion 95x is stepped and curved in multiple directions. In this case, stress concentrates in parts of the semiconductor chip 1 corresponding to the corners of the stepped delamination boundary portion 95x and parts of the semiconductor chip 1 corresponding to the inflection points of the curve, because the shape of the delamination boundary portion 95x changes significantly, resulting in higher stress than in the surrounding parts.

[0041] (Effects of the first embodiment) Next, the effects of the first embodiment will be described.

[0042] In the first embodiment, as described above, the laser beam shaping step includes a step of shaping the laser beam L into a straight line so that the delamination boundary portion 95 generated each time the laser beam L is irradiated becomes straight, and the laser beam irradiation step includes a step of irradiating a single semiconductor chip 1 multiple times with the laser beam L, which has been shaped into a straight line by the laser beam shaping step, while moving relative to the support substrate 10 from one end 1a to the other end 1b of the semiconductor chip 1 when viewed from a direction perpendicular to the surface of the support substrate 10. As a result, the semiconductor chip 1 is irradiated with the laser beam L multiple times in order to delaminate the semiconductor chip 1 from the support substrate 10. By irradiating with the laser beam L in multiple times, the spot area SA of the laser beam L irradiated onto the semiconductor chip 1 in order to delaminate the semiconductor chip 1 from the support substrate 10 can be made smaller compared to when the laser beam L is irradiated once. As a result, the impact on the semiconductor chip 1 caused by ablation by the laser beam L and the bending deformation of the object caused by laser beam irradiation can be suppressed so as not to exceed the physical strength of the semiconductor chip 1. Here, a case where the delamination boundary portion 95 is not linear is when the delamination boundary portion 95 is stepped or curved, bending in multiple directions. In parts of the semiconductor chip 1 corresponding to the corners of the stepped delamination boundary portion 95 or the inflection points of the curve, the shape of the delamination boundary portion 95 changes significantly, causing stress concentration and higher stress than in the surrounding areas. Therefore, in the semiconductor chip transfer method according to the first embodiment, by keeping the delamination boundary portion 95 linear, it is possible to eliminate parts where the shape of the delamination boundary portion 95 changes significantly, thereby suppressing localized stress concentration from the support substrate 10 to the semiconductor chip 1. This makes it possible to suppress localized and large impacts from the irradiation of laser light L on the semiconductor chip 1.

[0043] Furthermore, in the first embodiment, the laser beam forming process includes a step of forming the laser beam L in the laser beam forming process into a plurality of linearly arranged dot-shaped laser beams L such that the peel boundary portion 95 generated each time the laser beam L is irradiated is linear, and the laser beam irradiation process includes a step of irradiating a single semiconductor chip 1 multiple times with the plurality of dot-shaped laser beams L while moving relative to the support substrate 10 from one end 1a to the other end 1b of the semiconductor chip 1. As a result, the plurality of linearly arranged dot-shaped laser beams L are irradiated multiple times while moving relative to the support substrate 10 from one end 1a to the other end 1b of the semiconductor chip 1. As a result, the plurality of dot-shaped laser beams L are irradiated onto the support substrate 10. Here, when a line-shaped laser beam L is irradiated onto the support substrate 10, the spot area SA of the laser beam L is continuous in a line on the support substrate 10, so the irradiation energy of the laser beam L received by the support substrate 10 becomes large, and the force of the laser beam L to peel the semiconductor chip 1 from the support substrate 10 may be excessive. Therefore, by irradiating the support substrate 10 with multiple dot-shaped laser beams L, the respective spot regions SA of the multiple dot-shaped laser beams L can be arranged at intervals that ensure the minimum force necessary for the laser beams L to detach the semiconductor chip 1 from the support substrate 10. As a result, the impact on the semiconductor chip 1 caused by ablation by the laser beams L and the bending deformation of the object caused by laser irradiation can be minimized.

[0044] [Second Embodiment] The configuration of the semiconductor chip transfer apparatus according to the second embodiment is the same as that of the semiconductor chip transfer apparatus 100 according to the first embodiment, so a description will be omitted.

[0045] (Semiconductor chip transfer method) Next, with reference to Figure 4, a semiconductor chip transfer method according to the second embodiment will be described.

[0046] In step S1, similar to the semiconductor chip transfer method according to the first embodiment described above, the control unit 60 selects the semiconductor chip 1 to be transferred, which is supported on the support substrate 10.

[0047] In step S2a, the laser beam shaping step includes shaping the laser beam L in the laser beam shaping step into a plurality of dot-shaped laser beams L arranged in a straight line or arc, such that the delamination boundary portion 95a generated each time the laser beam L is irradiated is linear, extending from one side of the rectangular semiconductor chip 1 to another side different from that side, as shown in Figure 7. The laser beam irradiation step includes simultaneously irradiating a single semiconductor chip 1 with a plurality of dot-shaped laser beams L. Specifically, in the second embodiment, as shown in Figure 7, the laser beam L is irradiated multiple times onto a single semiconductor chip 1 while moving (scanning) relative to the support substrate 10 from one side of the semiconductor chip 1 to another side different from that side, as viewed from a direction perpendicular to the surface of the support substrate 10 (Z direction). Specifically, the laser beam L is irradiated onto the semiconductor chip 1 while scanning, from the first irradiation position P1 to the second irradiation position P2. At this time, the delamination boundary portion 95a generated each time the laser beam L is irradiated is linear.

[0048] In step S3, similar to the semiconductor chip transfer method according to the first embodiment described above, the control unit 60 determines whether or not the entire semiconductor chip 1 to be transferred has been transferred.

[0049] (Comparison with comparative example) Next, we will explain a comparison between the laser irradiation position when peeling a semiconductor chip from the support substrate from one side to the other according to the second embodiment and the laser irradiation position when peeling a semiconductor chip from the support substrate from one side to the other according to the comparative example.

[0050] In the second embodiment, as shown in Figure 7, the laser beam L irradiated onto the semiconductor chip 1 while scanning is composed of multiple dot-shaped laser beams L, at the first irradiation position P1, the second irradiation position P2, and the scanning laser beam L. In this case, the delamination boundary portion 95a is linear. On the other hand, in the comparative example, as shown in Figure 8, the laser beam is irradiated onto the semiconductor chip 1 while scanning from one end to the other, at the first irradiation position P1, the second irradiation position P2, and the third irradiation position P3. In this case, the delamination boundary portion 95y is stepped and curved in multiple directions. In this case, stress concentrates in parts of the semiconductor chip 1 corresponding to the corners of the stepped delamination boundary portion 95y and parts of the semiconductor chip 1 corresponding to the inflection points of the curve, because the shape of the delamination boundary portion 95y changes significantly, resulting in higher stress than in the surrounding parts.

[0051] (Effects of the second embodiment) Next, the effects of the second embodiment will be described.

[0052] In the second embodiment, as described above, the laser light forming step includes a step of forming the laser light L in the laser light forming step into a plurality of linearly arranged dot-shaped laser beams L such that the peel boundary portion 95a generated each time the laser light L is irradiated is linear, extending from one side of the rectangular semiconductor chip 1 to another side different from that side, and the laser light irradiation step includes a step of simultaneously irradiating a single semiconductor chip 1 with a plurality of dot-shaped laser beams L. As a result, since a plurality of dot-shaped laser beams L are irradiated onto a single semiconductor chip 1 simultaneously, the time required to peel off the semiconductor chip 1 can be shortened compared to the case where a plurality of dot-shaped laser beams L are irradiated sequentially.

[0053] [Third Embodiment] The configuration of the semiconductor chip transfer apparatus according to the third embodiment is the same as that of the semiconductor chip transfer apparatus 100 according to the first embodiment, so a description will be omitted.

[0054] (Semiconductor chip transfer method) Next, with reference to Figure 4, a semiconductor chip transfer method according to the third embodiment will be described.

[0055] In step S1, similar to the semiconductor chip transfer method according to the first embodiment described above, the control unit 60 selects the semiconductor chip 1 to be transferred, which is supported on the support substrate 10.

[0056] In step S2b, the laser shaping step includes shaping the laser beam L in the laser shaping step into a plurality of dot-shaped laser beams L arranged in an arc, such that the peeling boundary portion 95b generated each time the laser beam L is irradiated is arc-shaped, extending from one side of the rectangular semiconductor chip 1 to another side different from that side, as shown in Figure 9. The laser irradiation step includes simultaneously irradiating a single semiconductor chip 1 with a plurality of dot-shaped laser beams L. Specifically, in the third embodiment, as shown in Figure 9, the laser beam L is irradiated onto a single semiconductor chip 1 multiple times while moving (scanning) relative to the support substrate 10, from one side of the semiconductor chip 1 to another side different from that side, when viewed from a direction perpendicular to the surface of the support substrate 10 (Z direction). Specifically, the laser beam L is irradiated onto the semiconductor chip 1 while scanning, moving from the first irradiation position P1, the second irradiation position P2, the third irradiation position P3, the fourth irradiation position P4, and the fifth irradiation position P5. In this case, the delamination boundary portion 95b generated each time the laser light L is irradiated is arc-shaped. Also, for example, the crystal orientation of the single-crystal silicon that makes up the semiconductor chip 1 is along the X-axis.

[0057] In step S3, similar to the semiconductor chip transfer method according to the first embodiment described above, the control unit 60 determines whether or not the entire semiconductor chip 1 to be transferred has been transferred.

[0058] (Effects of the third embodiment) Next, the effects of the third embodiment will be described.

[0059] In the third embodiment, as described above, the laser light forming step includes a step of forming the laser light L in the laser light forming step into a plurality of dot-shaped laser beams L arranged in an arc shape such that the delamination boundary portion 95b generated each time the laser light L is irradiated is arc-shaped extending from one side of the rectangular semiconductor chip 1 to another side different from that side, and the laser light irradiation step includes a step of simultaneously irradiating a single semiconductor chip 1 with a plurality of dot-shaped laser beams L. If the delamination boundary portion 95b is parallel to the crystal orientation of the single crystal silicon that constitutes the semiconductor chip 1, the silicon is prone to fracture, and the semiconductor chip 1 may be damaged. In the semiconductor chip transfer method according to the third embodiment, by making the delamination boundary portion 95b arc-shaped, it is possible to prevent the delamination boundary portion 95b from being parallel to the crystal orientation of the single crystal silicon that constitutes the semiconductor chip 1. As a result, the semiconductor chip 1 can be transferred while further suppressing damage to the semiconductor chip 1.

[0060] [Fourth Embodiment] The configuration of the semiconductor chip transfer apparatus according to the fourth embodiment is the same as that of the semiconductor chip transfer apparatus 100 according to the first embodiment, so a description will be omitted.

[0061] (Semiconductor chip transfer method) Next, with reference to Figure 4, a semiconductor chip transfer method according to the fourth embodiment will be described.

[0062] In step S1, similar to the semiconductor chip transfer method according to the first embodiment described above, the control unit 60 selects the semiconductor chip 1 to be transferred, which is supported on the support substrate 10.

[0063] In step S2c, the laser beam shaping process includes a process of changing the number of a plurality of linearly arranged laser beams L according to the length of the peeling boundary portion 95c every time the laser beam L is irradiated. The laser beam irradiation process includes a process of irradiating the laser beam L while changing the number of a plurality of linearly arranged laser beams L according to the length of the peeling boundary portion 95c from one corner portion of the square semiconductor chip 1 toward the other corner portion facing the one corner portion. Specifically, in the fourth embodiment, as shown in FIG. 10, the laser beam L moves (scans) relatively to the support substrate 10 from one end 1a side of the square semiconductor chip 1 toward the other end 1b side while being perpendicular to the surface of the support substrate 10 (Z direction), and is irradiated to the single square semiconductor chip 1 a plurality of times. Specifically, the laser beam L is irradiated to the single square semiconductor chip 1 at the first irradiation position P1, the second irradiation position P2, the third irradiation position P3, and while scanning. At this time, the lengths of the single square peeling boundary portions 95c generated every time the laser beam L is irradiated are L1 for the first time, L2 for the second time, L3 for the third time, and L4 for the fourth time. Note that L1, L2, L3, and L4 have the relationship of L1 < L2 < L3 < L4.

[0064] In step S3, similarly to the semiconductor chip transfer method according to the first embodiment, the control unit 60 determines whether or not all of the semiconductor chips 1 to be transferred have been transferred.

[0065] (Effect of the Fourth Embodiment) Next, the effect of the fourth embodiment will be described.

[0066] In the fourth embodiment, as described above, the laser beam forming process includes a step of changing the number of linearly arranged laser beams L each time the laser beam L is irradiated, according to the length of the delamination boundary portion 95c. The laser beam irradiation process includes irradiating the rectangular semiconductor chip 1 from one corner toward the other corner opposite to the first corner, while changing the number of linearly arranged laser beams L according to the length of the delamination boundary portion 95c. In the method of adjusting the shape (length) of the laser beam L by changing the opening of the mask through which the laser beam L passes, it is not possible to adjust the shape (length) of the laser beam L without changing to a mask with a different opening size, which is time-consuming and requires effort to adjust the shape (length) of the laser beam L. In the process of irradiating the laser beam L, the shape (length) of the laser beam L can be adjusted by changing the number of linearly arranged laser beams L. This eliminates the need to change to a mask with a different opening size when adjusting the shape (length) of the laser beam L. As a result, the adjustment of the shape (length) of the laser beam L according to the length of the delamination boundary portion 95c becomes easier.

[0067] [Fifth Embodiment] The configuration of the semiconductor chip transfer apparatus according to the fifth embodiment is the same as that of the semiconductor chip transfer apparatus 100 according to the first embodiment, so a description will be omitted.

[0068] (Semiconductor chip transfer method) Next, with reference to Figure 4, a semiconductor chip transfer method according to the fifth embodiment will be described.

[0069] In step S1, similar to the semiconductor chip transfer method according to the first embodiment described above, the control unit 60 selects the semiconductor chip 1 to be transferred, which is supported on the support substrate 10.

[0070] In step S2d, as shown in FIG. 11, the laser beam shaping process includes a process of changing the number of a plurality of linearly arranged laser beams L according to the length of the peeling boundary portion 95d every time the laser beam L is irradiated. The laser beam irradiation process includes a process of irradiating the laser beam L while changing the number of a plurality of linearly arranged laser beams L according to the length of the peeling boundary portion 95d from one corner of the rectangular semiconductor chip 1 toward the other corner opposite to the one corner. Here, in the fifth embodiment, as shown in FIG. 11, the laser beam L is relatively moved (scanned) with respect to the support substrate 10 from one end side to the other end side of the rectangular semiconductor chip 1 as viewed from the direction (Z direction) perpendicular to the surface of the support substrate 10, and is irradiated a plurality of times to a single rectangular semiconductor chip 1. Specifically, the laser beam L is irradiated to a single rectangular semiconductor chip 1 at the first irradiation position P1, the second irradiation position P2, the third irradiation position P3, while being scanned. At this time, the lengths of the single rectangular peeling boundary portions 95d generated every time the laser beam L is irradiated are L1 for the first time, L2 for the second time, L3 for the third time, L4 for the fourth time, L5 for the fifth time, and L6 for the sixth time. Note that L1, L2, L3, L4, L5, and L6 have a relationship of L1 < L2 < L3 < L4 < L5 < L6.

[0071] In step S3, similar to the semiconductor chip transfer method according to the first embodiment, the control unit 60 determines whether or not all of the semiconductor chips 1 to be transferred have been transferred.

[0072] (Effect of the Fifth Embodiment) Next, the effect of the fifth embodiment will be described.

[0073] In the fifth embodiment, as described above, the laser beam forming process includes a step of changing the number of linearly arranged laser beams L each time the laser beam L is irradiated, according to the length of the delamination boundary portion 95d. The laser beam irradiation process includes irradiating the rectangular semiconductor chip 1 from one corner toward the other corner opposite to the first corner, while changing the number of linearly arranged laser beams L according to the length of the delamination boundary portion 95d. In the method of adjusting the shape (length) of the laser beam L by changing the opening of the mask through which the laser beam L passes, the shape (length) of the laser beam L cannot be adjusted unless the mask is changed to one with a different opening size, which is time-consuming and requires effort to adjust the shape (length) of the laser beam L. In the process of irradiating the laser beam L, the shape (length) of the laser beam L can be adjusted by changing the number of linearly arranged laser beams L. This eliminates the need to change the mask to one with a different opening size when adjusting the shape (length) of the laser beam L. As a result, the adjustment of the shape (length) of the laser beam L according to the length of the delamination boundary portion 95d becomes easier.

[0074] [Differentiation] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims rather than by the description of the embodiments above, and further includes all modifications (exceptions) within the meaning and scope equivalent to the claims.

[0075] For example, in the first to fifth embodiments described above, the laser light L emitted from the laser light oscillator 71 is formed into a line shape by the optical system 81, and the line-shaped laser light L is formed into a plurality of dot-shaped laser light L by the GLV 82. However, the laser light L emitted from the laser light oscillator 71 may also be formed into dots by a mask.

[0076] Furthermore, while the first to fifth embodiments described above show examples in which a line-shaped laser beam L is shaped into multiple dot-shaped laser beams L by the GLV82, the present invention is not limited thereto. For example, a diffractive optical element (DOE) that directly shapes the laser beam L emitted from the laser beam oscillator 71 into dot-shaped laser beams L may be used.

[0077] Furthermore, while the first to fifth embodiments described above show examples where the support substrate 10 is circular and the transfer substrate 20 is rectangular, the present invention is not limited thereto. For example, both the support substrate 10 and the transfer substrate 20 may be circular or polygonal.

[0078] Furthermore, while the first to fifth embodiments described above show examples in which the entire surface 1c of the semiconductor chip 1 is supported when it is supported on the support substrate 10 via the adhesive layer 2, the present invention is not limited thereto. For example, the semiconductor chip 1 may include a convex portion in part, and only the convex portion of the semiconductor chip 1 may be supported on the support substrate 10 via the adhesive layer 2.

[0079] Furthermore, while the first to fifth embodiments described above show examples in which the semiconductor chip 1 is used as the element of the present invention, the present invention is not limited thereto. Elements other than the semiconductor chip 1 may also be used as the element of the present invention.

[0080] Furthermore, while the first to fifth embodiments described above show examples in which the laser light L is irradiated onto a single semiconductor chip 1, the present invention is not limited thereto. For example, the laser light L may be irradiated onto multiple semiconductor chips 1.

[0081] Furthermore, while the fourth and fifth embodiments described above show examples in which the laser beams L are irradiated while changing the number of laser beams L arranged in a straight line, the present invention is not limited thereto. For example, the laser beams L may be irradiated while changing the number of laser beams L arranged in an arc. [Explanation of Symbols]

[0082] 1. Semiconductor chip (device) 1a One end of a semiconductor chip 1b Semiconductor chip other end 10 Support substrate 10a surface (surface supporting the element) 10b side (front) 80 Laser-formed section 90 Laser beam irradiation area 95, 95a, 95b, 95c, 95d Delamination boundary 100 Semiconductor chip transfer equipment (device transfer equipment) L Laser light L1~L6 Length of the delamination boundary P1~P6 Irradiation position of scanning laser beam SA Spot Area

Claims

1. A laser beam shaping process that shapes the laser beam into a straight line or an arc, The process includes a laser beam irradiation step of irradiating a single element multiple times with a support substrate on which the element is supported, from the side opposite to the surface on which the support substrate supports the element, The aforementioned laser photoforming process is, The process includes shaping the laser beam into a straight line or an arc so that the boundary portion where the element, generated each time the laser beam is irradiated, peels off from the support substrate is straight or arc-shaped. The laser light irradiation step is, The laser beam, which has been formed into a linear or arc shape by the laser beam shaping process, is irradiated onto a single element multiple times while moving relative to the support substrate from one end of the element to the other end, as viewed from a direction perpendicular to the surface of the support substrate. A method for transferring an element, comprising the step of peeling the element from the support substrate at the irradiation position of the laser light.

2. The aforementioned laser photoforming process is, The laser beam shaping process includes a step of shaping the laser beam into a plurality of dot-shaped laser beams arranged in a straight line or arc, such that the boundary portion where the element, generated each time the laser beam is irradiated, peels off from the support substrate is in a straight line or arc shape. The laser light irradiation step is, The method for transferring an element according to claim 1, further comprising the step of irradiating a single element multiple times with the plurality of dot-shaped laser beams while moving them relative to the support substrate from one end of the element to the other end.

3. The aforementioned laser photoforming process is, The laser beam shaping process includes a step of shaping the laser beam into a plurality of dot-shaped laser beams arranged in a straight line or arc, such that the boundary portion of the element that is generated each time the laser beam is irradiated is separated from the support substrate and is in a straight line or arc shape from one side of the rectangular element to another side different from the first side. The laser light irradiation step is, The method for transferring an element according to claim 2, further comprising the step of simultaneously irradiating a single element with a plurality of dot-shaped laser beams.

4. The aforementioned laser photoforming process is, Each time the laser beam is irradiated, the number of laser beams arranged in a straight line or arc is changed according to the length of the boundary portion where the element peels off from the support substrate, The laser light irradiation step is, The element transfer method according to claim 2, comprising the step of irradiating the rectangular element with laser light, changing the number of laser beams arranged in a straight line or arc according to the length of the boundary portion where the element peels off from the support substrate, from one corner of the rectangular element toward the other corner opposite the first corner.

5. A laser beam shaping unit that shapes the laser beam into a straight line or an arc, The system includes a laser beam irradiation unit that irradiates a single element multiple times with laser light from the side opposite to the surface on which the support substrate supports the element, toward the support substrate on which the element is supported, The laser photoforming section is The laser beam is shaped in a straight line or arc so that the boundary portion where the element, generated each time the laser beam is irradiated, separates from the support substrate is straight or arc-shaped. The laser light irradiation unit is An element transfer apparatus configured to irradiate a single element multiple times with the laser beam, which has been formed in a linear or arc shape by the laser beam shaping unit, while moving relative to the support substrate from one end of the element to the other end of the element, when viewed from a direction perpendicular to the surface of the support substrate.

Images