Method and device for transferring element

Abstract

To provide a method for transferring an element which can transfer an element while suppressing breakage of an element caused by deformation of an adhesive layer even when the element is relatively thin.SOLUTION: A method for transferring a semiconductor chip (a method for transferring an element) includes: an arrangement step of arranging an adhesive layer 2, a resist 3, and a semiconductor chip 1 in that order on a transfer substrate 10; and a transfer step of transferring a semiconductor chip 1 on a transfer target substrate 20 by radiating a laser beam L to the transfer substrate from the side opposite to the side of the transfer substrate 10 in which the semiconductor chip 1 is arranged. The adhesive force between the adhesive layer 2 and the resist 3 is larger than the adhesive force between the resist 3 and the semiconductor chip 1, and the resist 3 remains on the transfer substrate 10 side in the transfer step.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to an element transfer method and an element transfer apparatus, and more particularly to an element transfer method and an element transfer apparatus for transferring an element by irradiating a laser beam.

Background Art

[0002] Conventionally, an element transfer method for transferring an element by irradiating a laser beam has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a laser transfer method for transferring an article attached to a substrate to another substrate. In Patent Document 1, a blistering layer that deforms by irradiating a laser beam and an adhesive layer are provided between the substrate and the article, and the article is held by the adhesive layer. Then, in Patent Document 1, a laser beam is irradiated from the upper surface side of the substrate toward the blistering layer close to the adhesive layer, and the blistering layer deforms, so that the adhesive layer deforms convexly downward. As a result, the article is peeled off from the adhesive layer and transferred to another substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the conventional element transfer method as described in Patent Document 1, when the thickness of the article (element) is relatively small, due to the deformation of the adhesive layer (adhesive layer) during transfer, bending stress is applied to the element, and thus the element may be damaged. For this reason, even when the thickness of the element is relatively small, an element transfer method and an element transfer apparatus capable of transferring the element while suppressing damage to the element are desired.

[0006] The present invention has been made to solve the above-described problems, and one object of the present invention is to provide an element transfer method and an element transfer apparatus capable of transferring an element while suppressing damage to the element caused by deformation of the adhesive layer even in the case of an element having a relatively small thickness.

Means for Solving the Problems

[0007] In order to achieve the above object, an element transfer method according to a first aspect of the present invention includes an arranging step of arranging an adhesive layer, a release layer, and an element on a first substrate in this order, and a transferring step of irradiating the first substrate with laser light from the side opposite to the surface on which the element is arranged on the first substrate to transfer the element to a second substrate. The adhesive force between the adhesive layer and the release layer is greater than the adhesive force between the release layer and the element, and in the transferring step, the release layer remains on the first substrate side.

[0008] As described above, in the element transfer method according to the first aspect, the adhesive force between the adhesive layer and the release layer is greater than the adhesive force between the release layer and the element, and in the transferring step, the release layer remains on the first substrate side. As a result, since the adhesive force between the release layer and the element becomes relatively small, the bending stress applied to the element by the release layer deformed due to the deformation of the adhesive layer becomes small. Therefore, even when the element is relatively brittle, such as an element having a relatively small thickness, breakage of the element can be suppressed. As a result, an element transfer method capable of transferring an element while suppressing damage to the element caused by deformation of the adhesive layer can be provided. Further, since the release layer remains on the first substrate side, unlike the case where the release layer is transferred to the second substrate, the step of removing the release layer from the second substrate is reduced, so that the time required for the subsequent step of the step of transferring the element can be reduced.

[0009] In the element transfer method according to the first aspect, preferably, the placement step includes a step of placing an element on a first substrate via an adhesive layer and a release layer containing a resist. Here, in the manufacturing process of the element, a resist may be formed on the upper surface side of the element (the side opposite to the surface where the element and the manufacturing substrate face each other). Generally, the resist is transferred to the second substrate together with the element and is removed from the second substrate in a removal step in a subsequent step of the step of transferring the element. Therefore, if the release layer is configured to contain a resist, the resist remains on the first substrate side in the step of transferring the element. As a result, the time required for the subsequent steps of the step of transferring the element can be reduced by reducing the removal step of the resist from the second substrate.

[0010] In the element transfer method according to the first aspect, preferably, the placement step includes a step of placing an element on a first substrate via an adhesive layer and a release layer having a longitudinal elastic modulus greater than the longitudinal elastic modulus of the element. With this configuration, since the release layer has a longitudinal elastic modulus greater than the longitudinal elastic modulus of the element, the degree of deformation of the release layer becomes greater than the degree of deformation of the element. Thereby, the peeling of the element can be promoted. As a result, the element can be easily peeled off.

[0011] In this case, preferably, the transfer step includes a step of transferring the element while forming a gap between the release layer and the element by irradiating a laser beam, due to the difference in the degree of deformation caused by the difference in the longitudinal elastic modulus between the release layer and the element. With this configuration, the gap formed between the release layer and the element reduces the overall adhesive force between the release layer and the element, and can promote the peeling of the element while leaving the release layer on the first substrate side. As a result, by transferring the element while forming a gap between the release layer and the element, only the element can be more easily peeled off.

[0012] In the element transfer method according to the first aspect, preferably, the placement step includes a step of placing an element having a thickness smaller than the thickness of the release layer on the first substrate. In this way, even for an element having an extremely small thickness so as to be smaller than the thickness of the release layer, reducing the adhesive force between the release layer and the element to a relatively small value is particularly effective in suppressing damage to the element.

[0013] In the element transfer method according to the first aspect, preferably, the transfer step includes a step of irradiating a laser beam having a spot area smaller than the area of the element. Here, when the output density of the laser beam is equal, the larger the area of the spot region, the greater the height of the deformed portions of the adhesive layer and the release layer. That is, when transferring the element by a laser beam having a spot area equal to or larger than the area of the element, the bending stress applied to the element becomes large due to the relatively large height of the deformed portions of the adhesive layer and the release layer, so the element is likely to be damaged. Therefore, if the element is configured to be transferred by a laser beam having a spot area smaller than the area of the element, the height of the deformed portions of the adhesive layer and the release layer becomes relatively small, so the bending stress applied to the element becomes small, and damage to the element can be suppressed. As a result, the element can be transferred while suppressing damage to the element caused by deformation of the adhesive layer.

[0014] An element transfer apparatus according to a second aspect of the present invention includes a first substrate holding unit that holds a first substrate on which an adhesive layer, a release layer, and an element are arranged in this order, and is arranged on the side opposite to the surface of the first substrate on which the element is arranged, and irradiates a laser beam toward the first substrate to transfer the element to a second substrate. The adhesive force between the adhesive layer and the release layer is larger than the adhesive force between the release layer and the element, and the laser beam irradiation unit is configured to transfer the element so that the release layer remains on the first substrate side.

[0015] As described above, in the element transfer device according to this second aspect, the adhesive force between the adhesive layer and the release layer is greater than the adhesive force between the release layer and the element, and the laser light irradiation unit is configured to transfer the element so that the release layer remains on the first substrate side. As a result, since the adhesive force between the release layer and the element is relatively small, the bending stress applied to the element by the release layer deformed due to the deformation of the adhesive layer is reduced. Therefore, even when the element is relatively brittle, such as an element with a relatively small thickness, it is possible to suppress the element from being damaged. As a result, it is possible to provide an element transfer device that transfers the element while suppressing damage to the element caused by the deformation of the adhesive layer. Further, since the release layer remains on the first substrate side, the step of removing the release layer from the second substrate, which is required when the release layer is transferred to the second substrate, is reduced, so that the time required for the subsequent step of transferring the element can be reduced.

Advantages of the Invention

[0016] As described above, the element transfer method and the element transfer device of the present invention can transfer the element while suppressing damage to the element caused by the deformation of the adhesive layer even in the case of an element with a relatively small thickness.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0018] Hereinafter, embodiments embodying the present invention will be described with reference to the drawings.

[0019] With reference to FIGS. 1 to 4, the configuration of a semiconductor chip transfer device 100 according to an embodiment of the present invention will be described. Note that the semiconductor chip transfer device 100 is an example of the "element transfer device" in the claims.

[0020] (Semiconductor Chip Transfer Device) As shown in FIG. 1, the semiconductor chip transfer device 100 is configured to transfer the semiconductor chip 1 disposed on the transfer substrate 10 to the substrate to be transferred 20 by the laser lift-off method. Note that the transfer substrate 10 is an example of the "first substrate" in the claims. Also, the substrate to be transferred 20 is an example of the "second substrate" in the claims.

[0021] The semiconductor chip transfer device 100 includes a transfer substrate holding unit 30, a substrate to be transferred holding unit 40, a moving mechanism 50, a control unit 60, and a laser light irradiation unit 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. 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. Note that the transfer substrate holding unit 30 is an example of the "first substrate holding unit" in the claims.

[0022] As shown in FIG. 2, on the transfer substrate 10, a plurality of semiconductor chips 1 are arranged in a matrix (row - column shape) at a predetermined interval. The transfer substrate 10 has a circular shape. As the semiconductor chip 1, for example, a rectangular element having a side length of several tens of μm or more and several mm or less, such as an InP chip, and having a thickness of 200 nm or more and 800 nm or less is used.

[0023] As shown in FIG. 3, the transfer substrate 10 is formed of a material that transmits the laser light L, such as a SiO2 (silicon dioxide) substrate or a sapphire substrate, for example. The semiconductor chip 1 is disposed on the transfer substrate 10 via an adhesive layer 2, a resist 3, and a sacrificial layer 4. Note that the resist 3 is an example of the "release layer" in the claims. Both the sacrificial layer 4 and the semiconductor chip 1 are examples of the "element" in the claims. The adhesive layer 2 is also called a transfer material.

[0024] The adhesive layer 2 is disposed on the surface 10a on the Z2 side of the transfer substrate 10. The resist 3 is disposed on the surface 2a on the Z2 side of the adhesive layer 2. The sacrificial layer 4 is disposed on the surface 3a on the Z2 side of the resist 3. The semiconductor chip 1 is disposed on the surface 4a on the Z2 side of the sacrificial layer 4. The adhesive layer 2 is formed of a material that decomposes upon irradiation with the laser light L from the laser light irradiation unit 70 to generate gas components. And by generating gas components, the adhesive layer 2 deforms into a convex shape (see FIG. 7) protruding in the Z2 direction. The adhesive layer 2 is formed of, for example, polyimide or silicon.

[0025] The resist 3 is formed as a protective film (mask) when processing (patterning) the substrate in the manufacturing process of the semiconductor chip 1. As the resist 3, for example, "MICROPOSIT S1800 SERIES PHOTO RESIST" is used. The sacrificial layer 4 is formed to protect the surface of the semiconductor chip 1 in the manufacturing process of the semiconductor chip 1. Also, the sacrificial layer 4 is formed by growing crystals on the surface of the semiconductor chip 1 in the manufacturing process of the semiconductor chip 1. The semiconductor chip 1 and the sacrificial layer 4 are in contact via a chemical bond. The sacrificial layer 4 is formed of, for example, SiON.

[0026] As shown in FIG. 1, the transfer substrate holding unit 30 holds the transfer substrate 10 on which the semiconductor chip 1 is disposed via the adhesive layer 2, the resist 3, and the sacrificial layer 4. The transfer substrate holding unit 30 holds the transfer substrate 10 on which the semiconductor chip 1 is disposed with the surface on which the semiconductor chip 1 is disposed facing downward (in the Z2 direction). The transfer substrate holding unit 30 has an opening 31. The transfer substrate 10 held by the transfer substrate holding unit 30 is irradiated with the laser light L from the laser light irradiation unit 70 through the opening 31. The transfer substrate holding unit 30 is configured to be relatively movable with respect to the substrate to be transferred holding unit 40 at least in the X direction and the Y direction by the moving mechanism 50.

[0027] As shown in FIG. 3, the substrate to be transferred 20 is, for example, a substrate onto which a large number of semiconductor chips 1 arranged on the transfer substrate 10 are transferred in order to manufacture semiconductor products. An adhesive layer 21 for adhering the transferred semiconductor chips 1 is formed on the substrate to be transferred 20. Note that the adhesive layer 21 is also called a catch layer. Further, wiring electrically connectable to the transferred semiconductor chips 1 may be formed on the substrate to be transferred 20. The substrate to be transferred 20 has a rectangular shape.

[0028] The substrate to be transferred holding unit 40 holds the substrate to be transferred 20 onto which the semiconductor chips 1 arranged on the transfer substrate 10 are transferred from below (the Z2 side). The substrate to be transferred holding unit 40 is configured to be relatively movable with respect to the transfer substrate holding unit 30 at least in the X direction and the Y direction by a moving mechanism 50 (see FIG. 1). By performing one or both of the movement of the transfer substrate holding unit 30 and the movement of the substrate to be transferred holding unit 40 by the moving mechanism 50, the relative position of the semiconductor chips 1 arranged on the transfer substrate 10 with respect to the substrate to be transferred 20 can be adjusted.

[0029] As shown in FIG. 1, the control unit 60 is constituted by a processor such as a CPU (Central Processing Unit), for example, and performs various controls by executing a program (software). The control unit 60 arbitrarily selects the semiconductor chips 1 in the transfer region and controls the transfer of the selected semiconductor chips 1 onto the substrate to be transferred 20 by irradiating the laser light irradiation unit 70 with the laser light L. Further, the control unit 60 controls the operation of the moving mechanism 50 and the opening and closing operation of the slit 74.

[0030] The laser light irradiation unit 70 is configured to irradiate the transfer substrate 10 with the laser light L. The laser light irradiation unit 70 includes a laser light source 71, a galvano mirror 72, and an fθ lens 73. The laser light source 71 is a light source that emits the laser light L. The galvano mirror 72 is rotatable about two intersecting axes as rotation axes and reflects the laser light L at an arbitrary angle. The fθ lens 73 condenses the laser light L reflected by the galvano mirror 72 onto the transfer region of the transfer substrate 10.

[0031] Also, a slit 74 is provided between the laser light source 71 and the galvanometer mirror 72. By adjusting the size of the opening of the slit 74, the area SA (see FIG. 4) of the spot region of the laser light L is adjusted. The area SA of the spot region means the area on the adhesive layer 2 of the laser light L that has passed through the transfer substrate 10 and is irradiated onto the adhesive layer 2.

[0032] The laser light irradiation unit 70 irradiates the laser light L onto the surface 10b (see FIG. 3) on the opposite side of the surface 10a on which the semiconductor chip 1 of the transfer substrate 10 held by the transfer substrate holding unit 30 is disposed, via the galvanometer mirror 72 and the fθ lens 73. The laser light L is irradiated toward the selected semiconductor chip 1 by the galvanometer mirror 72 and the fθ lens 73.

[0033] As shown in FIG. 4, the laser light irradiation unit 70 irradiates the semiconductor chip 1 with the laser light L intermittently, for example. The control unit 60 controls the irradiation position of the laser light L so that the areas SA of the spot regions of the laser light L do not overlap each other. The area SA of the spot region of the laser light L is smaller than the area 1A of the semiconductor chip 1. The semiconductor chip 1 has, for example, a rectangular shape, and the length of one side of the semiconductor chip 1 is several tens of μm or more and several mm or less. Also, the spot region has, for example, a rectangular shape, and the length of one side of the spot region is several μm or more and several tens of μm or less.

[0034] (Semiconductor Chip Transfer Method) Next, with reference to FIGS. 5 and 6, the semiconductor chip transfer method of the present embodiment will be described.

[0035] As shown in FIGS. 6(a) and 6(b), the semiconductor chip 1 is placed on the transfer substrate 10 by a device or user (not shown). In the step of placing the semiconductor chip on the transfer substrate, as shown in FIG. 6(a), the manufacturing substrate 80 on which the semiconductor chip 1, the sacrificial layer 4, and the resist 3 are placed in this order is pressed against the transfer substrate 10 on which the adhesive layer 2 is placed so that the resist 3 and the adhesive layer 2 are in contact with each other. Then, as shown in FIG. 6(b), the semiconductor chip 1 is placed on the transfer substrate 10 by removing only the manufacturing substrate 80. Specifically, as shown in FIG. 6(a), the manufacturing substrate 80 is a substrate for manufacturing the semiconductor chip 1, and the semiconductor chip 1 is manufactured on the manufacturing substrate 80. The manufacturing substrate 80 and the semiconductor chip 1 are fixed by the tether portion T of the resist 3. Also, a space S is formed between the manufacturing substrate 80 and the semiconductor chip 1. The space S is formed by chemically removing a removal layer (not shown) formed in the manufacturing process of the semiconductor chip 1. As shown in FIG. 6(b), when the manufacturing substrate 80 is removed, the manufacturing substrate 80 and the semiconductor chip 1, the sacrificial layer 4, and the resist 3 are separated by the breaking of the tether portion T of the resist 3. The manufacturing substrate 80 is formed of, for example, InP.

[0036] After the step of placing the semiconductor chip on the transfer substrate, as shown in FIG. 5, in step S1, the control unit 60 irradiates a laser beam L from the side opposite to the surface 10a of the transfer substrate 10 on which the semiconductor chip 1 is placed (the Z1 side) toward the transfer substrate 10 on which the semiconductor chip 1 is placed via the adhesive layer 2, the resist 3, and the sacrificial layer 4. Then, when the laser beam L passes through the transfer substrate 10 and irradiates the adhesive layer 2, the sacrificial layer 4 and the semiconductor chip 1 are peeled off from the transfer substrate 10, and the sacrificial layer 4 and the semiconductor chip 1 are transferred from the transfer substrate 10 to the substrate to be transferred 20. That is, transfer by the laser lift-off method is performed. The outline of step S1 is shown in the step of transferring the semiconductor chip to the substrate to be transferred in FIG. 6(c). Here, in the present embodiment, the adhesive force RR (see FIG. 7) between the adhesive layer 2 and the resist 3 is larger than the adhesive force RS (see FIG. 7) between the resist 3 and the sacrificial layer 4. As a result, since the adhesive force RR (see FIG. 7) between the adhesive layer 2 and the resist 3 is larger than the adhesive force RS (see FIG. 7) between the resist 3 and the sacrificial layer 4, as shown in FIG. 6(c), in the step of transferring the semiconductor chip to the substrate to be transferred, the resist 3 remains on the transfer substrate 10 side. In FIGS. 6 and 9, for the sake of simplification of the figure, the semiconductor chip 1 is illustrated as if it were transferred by a single laser beam, but actually, as shown in FIG. 4, the semiconductor chip 1 is entirely peeled off and transferred by intermittently irradiating a laser beam having a spot area smaller than the area of the semiconductor chip 1 a plurality of times. The situation during the transfer of the semiconductor chip 1 will be described later.

[0037] In step S2, the control unit 60 determines whether or not all of the plurality of semiconductor chips 1 placed on the transfer substrate 10 have been transferred. In step S2, if the answer is No, the process returns to step S1. In step S2, if the answer is Yes, the process of the semiconductor chip transfer method ends.

[0038] (Situation during transfer of semiconductor chip) In this embodiment, as shown in FIG. 7, when the adhesive layer 2 is irradiated with the laser beam L, the adhesive layer 2 deforms into a convex shape protruding toward the Z2 side. Since the resist 3 has a relatively large longitudinal elastic modulus, the resist 3 deforms so as to follow the deformed adhesive layer 2. Further, since the resist 3 has a longitudinal elastic modulus larger than the longitudinal elastic moduli of the semiconductor chip 1 and the sacrificial layer 4, there is a difference in the degree of deformation between the resist 3, the semiconductor chip 1, and the sacrificial layer 4, so that a gap V is formed between the resist 3 and the sacrificial layer 4. Specifically, the degree of deformation of the semiconductor chip 1 and the sacrificial layer 4 is smaller than the degree of deformation of the resist 3. Thus, when the adhesive layer 2 and the resist 3 are deformed by the irradiation with the laser beam L, the semiconductor chip 1 and the sacrificial layer 4 cannot follow the deformation of the adhesive layer 2 and the resist 3, and a reaction force to return to the original shape is generated. When this reaction force becomes larger than the adhesive force between the resist 3 and the sacrificial layer 4, the sacrificial layer 4 peels off from the resist 3. As a result, the semiconductor chip 1 and the sacrificial layer 4 peel off from the resist 3, so that a gap V is formed between the resist 3 and the sacrificial layer 4. Here, since the semiconductor chip 1 and the sacrificial layer 4 are in contact via a chemical bond, the semiconductor chip 1 and the sacrificial layer 4 remain in contact when peeling off from the resist 3. The gap V promotes the peeling of the semiconductor chip 1 and the sacrificial layer 4 from the resist 3 by reducing the overall adhesive force between the resist 3 and the sacrificial layer 4. The resist 3 remains on the transfer substrate 10 side. The thickness t2 of the adhesive layer 2 is, for example, several μm or more and ten-odd μm or less. The thickness t3 of the resist 3 is, for example, several μm or more and ten-odd μm or less. The combined thickness of the thickness t4 of the sacrificial layer 4 and the thickness t1 of the semiconductor chip 1 is, for example, 200 nm or more and 800 nm or less. Note that the combined thickness of the thickness t4 of the sacrificial layer 4 and the thickness t1 of the semiconductor chip 1 is an example of the "thickness of the element" in the claims. Further, the thickness t3 of the resist 3 is an example of the "thickness of the peeling layer" in the claims.

[0039] (Influence of the magnitude relationship of the adhesive forces between the layers on the semiconductor chip) Here, FIG. 7 in the present embodiment shows the state of the semiconductor chip 1 when the adhesive force RR between the adhesive layer 2 and the resist 3 is greater than the adhesive force RS between the resist 3 and the sacrificial layer 4. FIG. 8, which is a comparative example of the present embodiment, shows the state of the semiconductor chip 1 when the adhesive force RR between the adhesive layer 2 and the resist 3 is less than or equal to the adhesive force RS between the resist 3 and the sacrificial layer 4. Here, it is assumed that the magnitudes of RR in FIGS. 7 and 8 are equal. The distance D (see FIGS. 7 and 8) indicates the distance between the blister B, which is the deformed portion of the adhesive layer 2 and the resist 3, and the boundary between the region where the resist 3 and the sacrificial layer 4 are peeled off and the region where the resist 3 and the sacrificial layer 4 are not peeled off. As shown in FIGS. 7 and 8, when the height h of the blister B is equal, the distance D is larger in FIG. 7. In FIG. 7 where the distance D is large, the bending stress applied to the semiconductor chip 1 by the blister B is smaller than in FIG. 8 where the distance D is small. In the case of FIG. 8, since the bending stress applied to the semiconductor chip 1 by the blister B is large, the semiconductor chip 1 breaks in the region where the bending stress of the semiconductor chip 1 is concentrated (the region surrounded by the broken line). Thus, making the adhesive force RR between the adhesive layer 2 and the resist 3 larger than the adhesive force RS between the resist 3 and the sacrificial layer 4 makes the semiconductor chip 1 less likely to break.

[0040] Also, even when the adhesive force RR between the adhesive layer 2 and the resist 3 is less than or equal to the adhesive force RS between the resist 3 and the sacrificial layer 4 as shown in FIG. 8, if the output of the laser beam L is reduced, the height h of the blister B becomes smaller, and the bending stress applied to the semiconductor chip 1 becomes smaller. However, if the output of the laser beam L is reduced too much, no gas component is generated in the adhesive layer 2, and no blister B is generated. For this reason, the semiconductor chip 1 is not transferred. That is, making the adhesive force RR between the adhesive layer 2 and the resist 3 larger than the adhesive force RS between the resist 3 and the sacrificial layer 4 is effective in transferring the semiconductor chip 1 while suppressing breakage of the semiconductor chip 1.

[0041] (Subsequent process to the process of transferring the semiconductor chip to the substrate to be transferred) Figs. 9(a) and 9(b) show the post-processes of the process of transferring the semiconductor chip 1 onto the substrate to be transferred 20 in the present embodiment. In the post-process of the process of transferring the semiconductor chip 1 onto the substrate to be transferred 20, unnecessary portions are removed in order to mount only the semiconductor chip 1 on a circuit board (not shown). Specifically, as shown in Fig. 9(a), for example, the adhesive layer between the chips is removed by the plasma gas 90. Also, as shown in Fig. 9(b), for example, the sacrificial layer is removed by immersing it in the cleaning liquid 91. Here, when the resist 3 is transferred onto the substrate to be transferred when transferring the semiconductor chip 1 onto the substrate to be transferred 20, different from the case of Fig. 9, a process of removing the resist 3 from the substrate to be transferred 20 is required in the post-process of the process of transferring the semiconductor chip 1 onto the substrate to be transferred 20. That is, in the present embodiment, since the resist 3 remains on the transfer substrate 10 side, the process of removing the resist 3 from the substrate to be transferred 20 is reduced in the post-process of the process of transferring the semiconductor chip 1 onto the substrate to be transferred 20. That is, the fact that the resist 3 remains on the transfer substrate 10 side when transferring the semiconductor chip 1 is effective in reducing the time required for the post-process of the process of transferring the semiconductor chip 1 onto the substrate to be transferred 20.

[0042] (Effects of the Embodiment) Next, the effects of the embodiment will be described.

[0043] In this embodiment, as described above, the adhesive force RR between the adhesive layer 2 and the resist 3 is greater than the adhesive force RS between the resist 3 and the sacrificial layer 4 provided on the surface of the semiconductor chip 1 facing the resist 3. In the step of transferring the semiconductor chip to the substrate to be transferred, the resist 3 remains on the side of the transfer substrate 10. As a result, since the adhesive force RS between the resist 3 and the sacrificial layer 4 provided on the surface of the semiconductor chip 1 facing the resist 3 becomes relatively small, the bending stress applied by the deformed resist 3 due to the deformation of the adhesive layer 2 to the sacrificial layer 4 and the semiconductor chip 1 becomes small. Therefore, even when the semiconductor chip 1 is relatively brittle, such as when the thickness t1 + t4 of the semiconductor chip 1 is relatively small, it is possible to suppress the semiconductor chip 1 from being damaged. As a result, it is possible to provide a semiconductor chip transfer method for transferring the semiconductor chip 1 while suppressing the damage of the semiconductor chip 1 caused by the deformation of the adhesive layer 2. Further, since the resist 3 remains on the side of the transfer substrate 10, unlike the case where the resist 3 is transferred to the substrate to be transferred 20, the step of removing the resist 3 from the substrate to be transferred 20 is reduced, so that the time required for the subsequent steps of the semiconductor chip transfer method can be reduced.

[0044] Also, in this embodiment, as described above, the step of disposing the semiconductor chip on the transfer substrate includes the step of disposing the semiconductor chip 1 on the transfer substrate 10 via the adhesive layer 2 and the release layer including the resist. Here, in the manufacturing process of the semiconductor chip, a resist may be formed on the upper surface side of the semiconductor chip (the side opposite to the surface where the semiconductor chip and the manufacturing substrate face each other with respect to the semiconductor chip). Generally, the resist is transferred to the substrate to be transferred together with the semiconductor chip and is removed from the substrate to be transferred in the removal step of the subsequent steps of the semiconductor chip transfer method. Therefore, if the release layer is configured to include the resist, in the step of transferring the semiconductor chip to the substrate to be transferred, the resist 3 remains on the side of the transfer substrate 10. As a result, since the step of removing the resist 3 from the substrate to be transferred 20 is reduced, the time required for the subsequent steps of the semiconductor chip transfer method can be reduced.

[0045] In addition, in the present embodiment, as described above, the step of disposing the semiconductor chip on the transfer substrate includes a step of disposing the semiconductor chip 1 on the transfer substrate 10 via the adhesive layer 2 and the resist 3 having a longitudinal elastic modulus greater than the longitudinal elastic moduli of the semiconductor chip 1 and the sacrificial layer 4. As a result, since the resist 3 has a longitudinal elastic modulus greater than the longitudinal elastic moduli of the semiconductor chip 1 and the sacrificial layer 4, the degree of deformation of the resist 3 becomes greater than the degrees of deformation of the sacrificial layer 4 and the semiconductor chip 1. Thereby, peeling of the sacrificial layer 4 provided on the semiconductor chip 1 can be promoted. As a result, the semiconductor chip 1 can be easily peeled off.

[0046] In addition, in the present embodiment, as described above, the step of transferring the semiconductor chip to the substrate to be transferred includes a step of forming a gap V between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1 by irradiating the laser beam L and depending on the difference in the degree of deformation due to the difference in the longitudinal elastic modulus between the resist 3, the semiconductor chip 1, and the sacrificial layer 4, and then transferring the semiconductor chip 1. With such a configuration, the gap V formed between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1 reduces the overall adhesive force between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1, and can promote the peeling of the semiconductor chip 1 while leaving the resist 3 on the transfer substrate 10 side. As a result, by transferring the semiconductor chip 1 while forming the gap V between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1, only the semiconductor chip 1 can be more easily peeled off.

[0047] In addition, in the present embodiment, as described above, the step of disposing the semiconductor chip on the transfer substrate includes a step of disposing the semiconductor chip 1 having a thickness smaller than the thickness t3 of the resist 3 on the transfer substrate 10. In this way, making the adhesive force RS between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1 relatively small even for the semiconductor chip 1 having an extremely small thickness so as to be smaller than the thickness t3 of the resist 3 is particularly effective in suppressing breakage of the semiconductor chip 1.

[0048] Further, in the present embodiment, as described above, the step of transferring the semiconductor chip to the substrate to be transferred includes a step of irradiating a laser beam L having a spot region with an area smaller than the area 1A of the semiconductor chip 1. Here, when the output density of the laser beam L is equal, the larger the area SA of the spot region, the larger the height h of the deformed portions (blisters B) of the adhesive layer 2 and the resist 3. That is, when transferring the semiconductor chip 1 with a laser beam L having a spot region with an area equal to or larger than that of the semiconductor chip 1, the bending stress applied to the semiconductor chip 1 becomes large due to the relatively large height h of the deformed portions (blisters B) of the adhesive layer 2 and the resist 3, so that the semiconductor chip 1 is likely to be damaged. Therefore, if the semiconductor chip 1 is configured to be transferred by a laser beam L having a spot region with an area smaller than the area 1A of the semiconductor chip 1, the height h of the deformed portions (blisters B) of the adhesive layer 2 and the resist 3 becomes relatively small, so that the bending stress applied to the semiconductor chip 1 becomes small, and damage to the semiconductor chip 1 can be suppressed. As a result, the semiconductor chip 1 can be transferred while suppressing damage to the semiconductor chip 1 caused by deformation of the adhesive layer 2.

[0049] [Modification Example] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims rather than the description of the above-described embodiments, and further includes all changes (modification examples) within the meaning and scope equivalent to the claims.

[0050] For example, in the above embodiment, an example in which a resist is applied as the release layer of the present invention is shown, but the present invention is not limited thereto. For example, the release layer may be formed of something other than a resist.

[0051] Further, in the above embodiment, an example in which the resist 3 has a longitudinal elastic modulus larger than the longitudinal elastic moduli of the semiconductor chip 1 and the sacrificial layer 4 is shown, but the present invention is not limited thereto. For example, the resist 3 may have a longitudinal elastic modulus equal to or less than the longitudinal elastic moduli of the semiconductor chip 1 and the sacrificial layer 4.

[0052] In the above embodiment, an example is shown in which a gap V is formed between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1 due to the difference in the degree of deformation caused by the difference between the longitudinal elastic modulus of the resist 3 and the longitudinal elastic moduli of the sacrificial layer 4 and the semiconductor chip 1, while transferring the sacrificial layer 4 and the semiconductor chip 1. However, the present invention is not limited to this. For example, a gap V may not be formed between the resist 3 and the sacrificial layer 4 provided on the semiconductor chip 1.

[0053] In the above embodiment, an example is shown in which the total thickness obtained by combining the thickness of the sacrificial layer 4 and the thickness of the semiconductor chip 1 is smaller than the thickness of the resist 3. However, the present invention is not limited to this. For example, the total thickness obtained by combining the thickness of the sacrificial layer 4 and the thickness of the semiconductor chip 1 may be equal to or greater than the thickness of the resist 3.

[0054] In the above embodiment, an example is shown in which the sacrificial layer 4 is provided on the surface of the semiconductor chip 1 facing the resist 3. However, the present invention is not limited to this. For example, as in the modified example shown in FIG. 10, the sacrificial layer 4 may not be provided on the surface of the semiconductor chip 1 facing the resist 3. Note that in FIG. 10, the adhesive force RR between the adhesive layer 2 and the resist 3 is greater than the adhesive force RT between the resist 3 and the semiconductor chip 1.

[0055] In the above embodiment, an example is shown in which the area SA of the spot region of the laser beam is smaller than the area 1A of the semiconductor chip 1. However, the present invention is not limited to this. For example, the area SA of the spot region of the laser beam may be equal to or greater than the area 1A of the semiconductor chip 1.

[0056] In the above embodiment, an example is shown in which the shape of the transfer substrate 10 is circular and the shape of the substrate to be transferred 20 is rectangular. However, the present invention is not limited to this. For example, the shapes of both the transfer substrate 10 and the substrate to be transferred 20 may be circular or polygonal.

[0057] In the above embodiment, an example is shown in which the intervals between the irradiation positions of the intermittently irradiated laser light L are equal on the semiconductor chip 1. However, the present invention is not limited to this. For example, the intervals between the irradiation positions of the intermittently irradiated laser light L may be adjusted to be different between the end side and the center side of the semiconductor chip 1.

[0058] In the above embodiment, an example is shown in which the manufacturing substrate 80 and the semiconductor chip 1 are fixed by the tether portion T of the resist 3. However, the present invention is not limited to this. For example, the manufacturing substrate 80 and the semiconductor chip 1 may be fixed by an adhesive instead of the tether portion T of the resist 3. When the manufacturing substrate 80 and the semiconductor chip 1 are fixed by an adhesive, there is no space S between the manufacturing substrate 80 and the semiconductor chip 1.

[0059] In the above embodiment, an example is shown in which the spot region of the laser light has a rectangular shape. However, the present invention is not limited to this. For example, the spot region of the laser light may have a circular shape.

[0060] In the above embodiment, an example is shown in which an element having a small thickness such as an InP chip is applied as the semiconductor chip 1. However, the present invention is not limited to this. For example, various semiconductor elements other than the InP chip may be applied as the semiconductor chip 1.

[0061] In the above embodiment, an example is shown in which the moving mechanism 50 is configured to be capable of moving both the transfer substrate holding portion 30 and the substrate to be transferred holding portion 40. However, the present invention is not limited to this. For example, the moving mechanism 50 may be provided separately for the transfer substrate holding portion 30 and the substrate to be transferred holding portion 40.

Explanation of Reference Numerals

[0062] 1 Semiconductor chip (element) 1A Area of semiconductor chip (area of element) 2 Adhesive layer 3 Resist (release layer) 4 Sacrificial layer 10 Transfer substrate (first substrate) 10a surface (surface on which the element is disposed, surface for disposing the element) 20 Transfer substrate (second substrate) 30 Transfer substrate holding portion (first substrate holding portion) 70 Laser light irradiation unit 100 Semiconductor chip transfer device (element transfer device) L Laser light SA Area of the spot region V Void t1, t4 Thickness (thickness of the element) t3 Thickness (thickness of the release layer) RR Adhesive force (adhesive force between the adhesive layer and the release layer) RS, RT Adhesive force (adhesive force between the release layer and the element)

Claims

1. An arranging step of arranging an adhesive layer, a release layer, and an element on a first substrate in this order; A transfer step of irradiating laser light toward the first substrate from the side opposite to the surface of the first substrate on which the element is arranged, and transferring the element to a second substrate, the method comprising: The adhesive force between the adhesive layer and the release layer is greater than the adhesive force between the release layer and the element; In the transfer step, the release layer remains on the first substrate side, the element transfer method.

2. The arranging step includes a step of arranging the element on the first substrate through the adhesive layer and the release layer containing a resist, the element transfer method according to claim 1.

3. The arranging step includes a step of arranging the element on the first substrate through the adhesive layer and the release layer having a longitudinal elastic modulus greater than the longitudinal elastic modulus of the element, the element transfer method according to claim 1.

4. The transfer step includes a step of irradiating the laser light to transfer the element while forming a gap between the release layer and the element due to a difference in the degree of deformation due to a difference in the longitudinal elastic modulus between the release layer and the element, the element transfer method according to claim 3.

5. The arranging step includes a step of arranging the element having a thickness smaller than the thickness of the release layer on the first substrate, the element transfer method according to claim 1.

6. The transfer step includes a step of irradiating the laser light having a spot area smaller than the area of the element, the element transfer method according to claim 1.

7. A first substrate holding portion for holding a first substrate on which an adhesive layer, a release layer, and an element are arranged in this order; A laser light irradiation portion that is arranged on the side opposite to the surface of the first substrate on which the element is arranged, irradiates laser light toward the first substrate, and transfers the element to a second substrate; The adhesive force between the adhesive layer and the release layer is greater than the adhesive force between the release layer and the element; The laser light irradiation portion is configured to transfer the element so that the release layer remains on the first substrate side, the element transfer device.

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