Element transfer method and element transfer device

Abstract

To provide an element transfer method and element transfer apparatus capable of peeling the element from an adhesive layer even for elements with relatively small thickness.SOLUTION: The semiconductor chip transfer method (element transfer method) comprises: a charging process for charging at least a second substrate among the elements placed on a first substrate via an adhesive layer and the second substrate; and a transfer process for transferring elements to the second substrate by irradiating the first substrate with laser light from the side opposite to where the elements of the first substrate are placed, while at least the second substrate is charged among the elements and the second substrate, and the charging process includes a process for charging at least the second substrate among the elements and the second substrate so that electrostatic attraction acts on the elements and the second substrate during the transfer process.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to an element transferring method and an element transferring apparatus, and more particularly to an element transferring method and an element transferring apparatus for transferring elements by irradiating them with laser light. [Background technology]

[0002] BACKGROUND ART Conventionally, there is known an element transfer method in which an element is transferred by irradiating it with laser light (see, for example, Patent Document 1).

[0003] The above-mentioned Patent Document 1 discloses a laser transfer method for transferring an article attached to a substrate to another substrate. In the above-mentioned Patent Document 1, a blistering layer that deforms when irradiated with laser light and an adhesive layer are provided between the substrate and the article, and the article is held by the adhesive layer. In the above-mentioned Patent Document 1, laser light is irradiated from the upper surface side of the substrate toward the blistering layer adjacent to the adhesive layer, and the blistering layer deforms, causing the adhesive layer to deform into a downward convex shape. 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] Special Publication No. 2014-515883 Summary of the Invention [Problem to be solved by the invention]

[0005] In a conventional element transfer method such as that described in Patent Document 1, if the thickness of the article (element) is relatively small, the element's own weight is smaller than the adhesive force between the adhesive layer (adhesive layer) and the element, and the element may not be peeled off from the adhesive layer and transferred to another substrate. Therefore, there is a demand for an element transfer method and element transfer device that can peel off an element from the adhesive layer even when the element is relatively thin.

[0006] The present invention has been made to solve the above-mentioned problems, and one object of the present invention is to provide an element transfer method and element transfer device that are capable of peeling an element from an adhesive layer even in the case of an element with a relatively small thickness. [Means for solving the problem]

[0007] In order to achieve the above object, an element transfer method according to a first aspect of the present invention includes a charging step of charging an element arranged on a first substrate via an adhesive layer and at least the second substrate out of the second substrate, and a transfer step of irradiating laser light toward the first substrate from the side opposite to the side on which the element is arranged on the first substrate, while the element and at least the second substrate out of the second substrate are charged, thereby transferring the element to the second substrate, wherein the charging step includes a step of charging at least the second substrate out of the element and the second substrate so that an electrostatic attraction force acts on the element and the second substrate in the transfer step.

[0008] In the element transfer method according to the first aspect, as described above, in the step of irradiating a laser beam toward the first substrate from the side opposite to the side on which the elements are arranged to transfer the elements to the second substrate, at least the second substrate out of the elements and the second substrate is charged so that an electrostatic attraction force acts on the elements and the second substrate. As a result, the electrostatic attraction force acting on the elements acts to assist in peeling the elements from the adhesive layer, so that even in the case of elements with a relatively small thickness, the elements can be peeled from the adhesive layer.

[0009] In the element transfer method according to the first aspect, the charging step preferably includes charging at least the surface of the second substrate facing the element among the surfaces of the element and the second substrate facing each other in the transfer step, and the transfer step includes irradiating a laser beam toward the first substrate from the side opposite to the side on which the element is disposed, while charging at least the surface of the second substrate facing the element among the surfaces of the element and the second substrate facing each other, thereby transferring the element to the second substrate. With this configuration, the distance between the charged surfaces of the element and the second substrate is relatively small, and therefore the electrostatic attraction force acting on the element and the second substrate is relatively large. As a result, the relatively large electrostatic attraction force acts to assist in the release of the element from the adhesive layer, making it easy to release the element from the adhesive layer even in the case of an element with a relatively small weight, such as a relatively thin element.

[0010] In the element transfer method according to the first aspect, the charging step preferably includes a step of charging the second substrate to a polarity different from the polarity to which the elements are likely to be charged by peeling charging, and the transferring step preferably includes a step of irradiating a laser beam toward the first substrate from the side opposite to the side on which the elements are arranged on the first substrate, while the second substrate is charged to a polarity different from the polarity to which the elements are likely to be charged by peeling charging, thereby transferring the elements to the second substrate. With this configuration, the elements and the second substrate can be charged to different polarities without actively charging the elements, thereby allowing an electrostatic attraction force to act on the elements and the second substrate. As a result, the elements can be easily peeled from the adhesive layer.

[0011] In the element transfer method according to the first aspect, the charging step preferably includes a step of charging the second substrate to a positive polarity that is different from the polarity to which elements made of a silicon-containing material are likely to be charged by peeling charging, and the transferring step preferably includes a step of irradiating a laser beam toward the first substrate from the side opposite to the side on which the elements of the first substrate are arranged, in a state in which the second substrate is charged to a positive polarity that is different from the polarity to which elements made of a silicon-containing material are likely to be charged by peeling charging. In this way, even for elements made of a silicon-containing material, the elements and the second substrate can be charged to different polarities without the need to actively charge the elements, so that an electrostatic attraction force can be easily exerted on the elements and the second substrate.

[0012] In the element transferring method according to the first aspect, the charging step preferably includes a step of charging both the element and the second substrate to polarities opposite to each other, and the transferring step preferably includes a step of irradiating a laser beam toward the first substrate from a side of the first substrate opposite to the side on which the element is arranged, in a state in which an electrostatic attraction force acts on the element and the second substrate by charging both the element and the second substrate to polarities opposite to each other, thereby transferring the element to the second substrate. With this configuration, the electrostatic attraction force can be more effectively exerted on the element and the second substrate.

[0013] In the element transfer method according to the first aspect, the charging step preferably includes at least a second charging step of: a first charging step of charging the element by irradiating ions while moving a first charging unit that irradiates ions to charge the element relative to the element in a direction along the surface of the element; and a second charging step of charging the second substrate by irradiating ions while moving a second charging unit that irradiates ions to charge the element relative to the second substrate in a direction along the surface of the second substrate. With this configuration, at least the second substrate out of the element and the second substrate can be charged simply by moving the charging unit that irradiates ions, so that the element can be easily peeled off from the adhesive layer.

[0014] In this case, the first charging step preferably includes a step of irradiating ions onto the elements while moving the first charging unit relative to the elements in a direction along the surface of the elements from one end to the other end of the area where the elements are arranged, and the second charging step preferably includes a step of irradiating ions onto the second substrate while moving the second charging unit relative to the second substrate in a direction along the surface of the second substrate from one end to the other end of at least the area where the elements are arranged, to charge the second substrate. This configuration allows at least the second substrate, of the elements and the second substrate, to be charged over a wider area, thereby increasing the electrostatic attraction force acting on the elements and the second substrate. This allows the elements to be effectively peeled off from the adhesive layer.

[0015] An element transfer device according to a second aspect of the present invention includes a first substrate holding unit that holds a first substrate on which elements are arranged via an adhesive layer so that a predetermined distance is maintained between the elements and the second substrate, a charging unit that charges at least the second substrate out of the elements and the second substrate, and a laser light irradiation unit that irradiates laser light toward the first substrate from the side opposite to the side on which the elements are arranged on the first substrate, and the laser light irradiation unit is configured to irradiate laser light toward the first substrate in a state in which at least the second substrate out of the elements and the second substrate is charged so that an electrostatic attraction force acts on the elements and the second substrate when the elements are transferred, thereby transferring the elements to the second substrate.

[0016] In the element transfer device according to this second aspect, as described above, the laser light irradiation unit is configured to transfer the elements to the second substrate by irradiating laser light toward the first substrate while charging at least the second substrate among the elements and the second substrate so that an electrostatic attraction force acts on the elements and the second substrate when transferring the elements. This allows the electrostatic attraction force acting on the elements to assist in peeling the elements from the adhesive layer, so that the elements can be peeled from the adhesive layer even in the case of elements with a relatively small weight, such as elements with a relatively small thickness. As a result, it is possible to provide an element transfer device that can peel elements from the adhesive layer even in the case of elements with a relatively small thickness. [Effects of the Invention]

[0017] As described above, the element transfer method and element transfer apparatus of the present invention can peel the element from the adhesive layer even in the case of an element having a relatively small thickness. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a schematic diagram showing the overall configuration of a semiconductor chip transfer device according to a first embodiment. [Figure 2] FIG. 1 is a plan view showing a state in which a semiconductor chip according to a first embodiment is arranged on a transfer substrate. [Figure 3] 1 is a cross-sectional view of a semiconductor chip transfer apparatus according to a first embodiment. [Figure 4] FIG. 3 is a diagram for explaining a spot area of ​​a laser beam according to the first embodiment. [Figure 5] 4 is a flowchart for explaining a process of the semiconductor chip transfer method according to the first embodiment. [Figure 6] 5A to 5C are schematic views for explaining a step of charging the semiconductor chip according to the first embodiment. [Figure 7] 5A to 5C are schematic views for explaining a step of charging a transferred portion according to the first embodiment. [Figure 8] 3A and 3B are diagrams showing a surface to be charged of a semiconductor chip and a charging portion according to the first embodiment; [Figure 9] 3A and 3B are diagrams illustrating a surface to be charged of a transferred portion and a charging portion according to the first embodiment. [Figure 10] 5 is a cross-sectional view for explaining a force applied to the semiconductor chip after laser light irradiation according to the first embodiment. FIG. [Figure 11] 10 is a flowchart for explaining the steps of a semiconductor chip transfer method according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings.

[0020] [First embodiment] The configuration of a semiconductor chip transfer apparatus 100 according to a first embodiment of the present invention will be described with reference to Figures 1 to 4. The semiconductor chip transfer apparatus 100 is an example of the "element transfer apparatus" in the claims.

[0021] (Semiconductor chip transfer device) As shown in Fig. 1, a semiconductor chip transfer device 100 is configured to transfer a semiconductor chip 1 arranged on a transfer substrate 10 to a transfer target portion 20 by a laser lift-off method. The transfer substrate 10 is an example of a "first substrate" in the claims. The transfer target portion 20 is an example of a "second substrate" in the claims.

[0022] The semiconductor chip transfer apparatus 100 includes a transfer substrate holding unit 30, a transferee substrate holding unit 40, a drive mechanism 50, a control unit 60, a laser light irradiation unit 70, and a charging unit 80. In FIG. 1, the left-right direction of the semiconductor chip transfer apparatus 100 (one direction in a horizontal plane) is defined as the X direction. The up-down direction (vertical direction) of the semiconductor chip transfer apparatus 100 is defined as the Z direction. The upward direction is defined as the Z1 direction, and the downward direction is defined as the Z2 direction. The direction perpendicular to the X and Z directions of the semiconductor chip transfer apparatus 100 (the other direction in a horizontal plane) is defined as the Y direction. The transfer substrate holding unit 30 is an example of a "first substrate holding unit" in the claims.

[0023] The charging unit 80 is configured to emit ions of positive or negative polarity by, for example, corona discharge. The charging unit 80 includes a first charging unit 80a and a second charging unit 80b. The first charging unit 80a is configured to emit ions of negative polarity. The second charging unit 80b is configured to emit ions of positive polarity.

[0024] As shown in FIG. 2, a plurality of semiconductor chips 1 are arranged in a matrix (rows and columns) at predetermined intervals on the transfer substrate 10. The transfer substrate 10 has, for example, a circular shape. The semiconductor chip 1 is, for example, a thin element, such as a memory, that is rectangular with a side length of several tens of μm to several mm and has a thickness of several μm to 30 μm. The semiconductor chip 1 is made of a material containing silicon. The semiconductor chip 1 is an example of an "element" in the claims.

[0025] 3, the semiconductor chip 1 is placed on a transfer substrate 10 via an adhesive layer 2. The transfer substrate 10 is formed of a material that transmits laser light L, such as an SiO2 (silicon dioxide) substrate or a sapphire substrate. The adhesive layer 2 is also called a transfer material.

[0026] The adhesive layer 2 is disposed on the Z2-side surface 10a of the transfer substrate 10. The semiconductor chip 1 is disposed on the Z2-side surface 2a of the adhesive layer 2. The adhesive layer 2 is formed from a material that decomposes and generates gas components when irradiated with laser light L from the laser light irradiation unit 70 (see FIG. 1). By generating the gas components, the adhesive layer 2 is deformed into a convex shape (see FIG. 10) that protrudes toward the Z2 side. The adhesive layer 2 is formed, for example, from a material containing resin.

[0027] As shown in FIGS. 1 and 3, the transfer substrate holding unit 30 holds a transfer substrate 10 on which a semiconductor chip 1 is arranged via an adhesive layer 2. The transfer substrate holding unit 30 holds the transfer substrate 10 on which the semiconductor chip 1 is arranged, with the surface on which the semiconductor chip 1 is arranged facing downward (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 laser light L from a laser light irradiation unit 70 through the opening 31. The transfer substrate holding unit 30 is configured to be movable relative to the transferred substrate holding unit 40 in at least the X direction and Y direction by a drive mechanism 50.

[0028] 3, the transferred portion 20 includes an adhesive layer 20a for adhering the transferred semiconductor chip 1 and a transferred substrate 20b on which the adhesive layer 20a is disposed. The transferred portion 20 is, for example, a substrate onto which a large number of semiconductor chips 1 disposed on a transfer substrate 10 are transferred during the manufacturing process of a semiconductor product. The transferred portion 20 may also have wiring formed thereon that can be electrically connected to the transferred semiconductor chip 1. The transferred portion 20 has a rectangular shape in a plan view. The adhesive layer 20a is also called a catch layer.

[0029] The transfer substrate holding unit 40 holds the transfer substrate 20b, onto which the semiconductor chip 1 arranged on the transfer substrate 10 is transferred, from below (Z2 side). The transfer substrate holding unit 40 is configured to be movable relative to the transfer substrate holding unit 30 at least in the X and Y directions by a drive 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 transfer substrate holding unit 40 by the drive mechanism 50, it is possible to adjust the relative position of the semiconductor chip 1 arranged on the transfer substrate 10 with respect to the transfer substrate 20.

[0030] 1, the control unit 60 is configured with a processor such as a CPU (Central Processing Unit) and performs various controls by executing a program (software). The control unit 60 arbitrarily selects a semiconductor chip 1 in the transfer area and controls the laser light emitting unit 70 to irradiate laser light L, thereby transferring the selected semiconductor chip 1 to the transfer target unit 20. To irradiate the laser light L onto the selected semiconductor chip 1, the control unit 60 rotates a galvanometer mirror 72 to reflect the laser light L at an arbitrary angle. The control unit 60 also controls the operation of the drive mechanism 50, the operation of the charging unit 80, and the opening and closing of the slit 74.

[0031] The laser light irradiation unit 70 is configured to irradiate the transfer substrate 10 with laser light L. The laser light irradiation unit 70 includes a laser light source 71, a galvanometer mirror 72, and an fθ lens 73. The laser light source 71 is a light source that emits laser light L. The galvanometer 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 focuses the laser light L reflected by the galvanometer mirror 72 onto the transfer region of the transfer substrate 10.

[0032] A slit 74 is provided between the laser light source 71 and the galvanometer mirror 72. The size of the opening of the slit 74 is adjusted to adjust the area SA (see FIG. 4) of the spot region of the laser light L. The area SA of the spot region means the area on the surface of 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.

[0033] The laser light irradiation unit 70 irradiates laser light L via a galvanometer mirror 72 and an fθ lens 73 onto a surface 10b (see FIG. 3) opposite to a surface 10a on which the semiconductor chip 1 is arranged of the transfer substrate 10 held by the transfer substrate holding unit 30. The laser light L is focused by the galvanometer mirror 72 and the fθ lens 73 onto the selected semiconductor chip 1.

[0034] As shown in FIG. 4, the laser light irradiation unit 70 (see FIG. 1) intermittently irradiates the semiconductor chip 1 with laser light L, for example. The control unit 60 (see FIG. 1) controls the irradiation position of the laser light L so that the areas SA of the spot areas of the laser light L do not overlap each other. The control unit 60 also moves the irradiation position of the laser light L relative to the transfer substrate 10, controlling the irradiation position of the laser light L so that the laser light L is irradiated from one end side 1a (see FIG. 3) to the other end side 1b (see FIG. 3) in the X-axis direction of the semiconductor chip 1. The area SA of the spot area of ​​the laser light L is smaller than the area 1A of the semiconductor chip 1. The laser outputs of all the intermittently irradiated laser lights L are the same. The spot area of ​​the laser light L has, for example, a rectangular shape, with a side length of several μm to several tens of μm.

[0035] (Semiconductor chip transfer method) Next, the semiconductor chip transfer method of the first embodiment will be described with reference to FIGS.

[0036] As shown in FIG. 5, in step S1, the control unit 60 (see FIG. 1) neutralizes the semiconductor chip 1 and the transferred portion 20 using a static eliminator such as an ionizer (not shown).

[0037] In step S2, the control unit 60 (see FIG. 1) charges the semiconductor chip 1 and the transferred unit 20 to polarities opposite to each other. Specifically, as shown in FIG. 6, the control unit 60 operates the first charger 80a to emit negative ions, and then moves the first charger 80a relative to the transfer substrate holding unit 30 (semiconductor chip 1) so that the emitted negative ions impinge on the semiconductor chip 1, thereby charging the semiconductor chip 1 to a negative polarity. Also, as shown in FIG. 7, the control unit 60 operates the second charger 80b to emit positive ions, and then moves the second charger 80b relative to the transferred substrate holding unit 40 (transferred unit 20) so that the emitted positive ions impinge on the transferred unit 20, thereby charging the transferred unit 20 to a positive polarity. Here, the first charging section 80a and the second charging section 80b are moved relative to the transfer substrate holding section 30 and the transferred substrate holding section 40, respectively, by operating the drive mechanism 50.

[0038] The process of charging the semiconductor chip 1 in step S2 is outlined in FIGS. 6(a), 6(b), and 6(c). In the first embodiment, as shown in FIGS. 6(a), 6(b), and 6(c), a first charging unit 80a emitting negative ions Ia is moved along the surface of the semiconductor chip 1 from one end to the other end of the area where the semiconductor chip 1 is to be placed, thereby negatively charging the surface of the semiconductor chip 1 opposite the adhesive layer 2. Here, the surface of the semiconductor chip 1 opposite the adhesive layer 2 is the surface that faces the transfer target 20 when the semiconductor chip 1 is transferred. Note that FIG. 6(a) shows a state in which the first charging unit 80a is located at one end of the area where the semiconductor chip 1 is to be placed. Also, FIG. 6(b) shows a state in which the first charging unit 80a is located in the center of the area where the semiconductor chip 1 is to be placed. Also, FIG. 6(c) shows a state in which the first charging unit 80a is located at the other end of the area where the semiconductor chip 1 is to be placed.

[0039] 8 shows the surface to be charged of the semiconductor chip 1 in the state shown in FIG. 6(b) and the first charging unit 80a. As shown in FIG. 8, in a plane along the surface of the semiconductor chip 1, in a direction perpendicular to the direction in which the first charging unit 80a moves when charging the semiconductor chip 1, the length Da of the first charging unit 80a is equal to or greater than the length da of the area in which the semiconductor chip 1 is arranged. Therefore, by moving the first charging unit 80a in a direction along the surface of the semiconductor chip 1 from one end to the other end of the area in which the semiconductor chip 1 is arranged, it is possible to charge all of the semiconductor chips 1 arranged on the transfer substrate 10.

[0040] The process of charging the transferee 20 in step S2 is outlined in FIGS. 7(a), 7(b), and 7(c). In the first embodiment, as shown in FIGS. 7(a), 7(b), and 7(c), the second charging unit 80b, which emits positive ions Ib, is moved along the surface of the transferee 20 from one end to the other end of the transferee 20, thereby positively charging the surface of the transferee 20 opposite the transferee substrate holding unit 40. Here, the surface of the transferee 20 opposite the transferee substrate holding unit 40 is the surface that faces the semiconductor chip 1 when the semiconductor chip 1 is transferred. Note that FIG. 7(a) shows a state in which the second charging unit 80b is located at one end of the transferee 20. Also, FIG. 7(b) shows a state in which the second charging unit 80b is located at the center of the transferee 20. 7(c) shows a state in which the second charging portion 80b is located on the other end side of the transferred portion 20. In FIG.

[0041] 9 shows the charged surface of the transferred unit 20 in the state shown in FIG. 7(b) and the second charging unit 80b. As shown in FIG. 9, in a plane along the surface of the transferred unit 20, in a direction perpendicular to the direction in which the second charging unit 80b moves when charging the transferred unit 20, the length Db of the second charging unit 80b is equal to or greater than the length db of the transferred unit 20. Therefore, by moving the second charging unit 80b in a direction along the surface of the transferred unit 20 from one end to the other end of the transferred unit 20, it is possible to charge the entire area of ​​the transferred unit 20.

[0042] The temperature, humidity, air pressure, and dielectric constant of the space in which the semiconductor chip transfer device 100 is installed are preferably managed and controlled. For example, because the critical charging voltage drops sharply when the humidity exceeds 40%, it is preferable to manage and control the humidity in the space to 40% or less using air conditioning equipment. Furthermore, based on Paschen's law, it is preferable to manage and control the air pressure in the space using a pressure / decompression pump or the like to prevent spark discharge before laser transfer. Furthermore, it is preferable to manage and control the dielectric constant in the space by gas replacement or the like so that the electrostatic attraction force C (see FIG. 10) acting on the semiconductor chip 1 and the transfer target 20 is optimal.

[0043] Returning to FIG. 5, in step S3, the control unit 60 (see FIG. 1) holds the transfer substrate 10 so that the semiconductor chip 1 and the transferred portion 20 are spaced a predetermined distance apart. Specifically, the control unit 60 causes the drive mechanism 50 to move the transfer substrate holding unit 30, which holds the transfer substrate 10 on which the semiconductor chip 1 is arranged, relative to the transferred substrate holding unit 40, to hold the transfer substrate 10 so that the semiconductor chip 1 and the transferred portion 20 are spaced a predetermined distance apart. The state of the semiconductor chip 1 after step S3 is shown in FIG. 3. As shown in FIG. 3, the semiconductor chip 1 is held at a predetermined distance D from the transferred portion 20. Electrostatic attraction forces act on the semiconductor chip 1 and the transferred portion 20, which are charged with opposite polarities and spaced apart by the predetermined distance D, in directions that attract each other.

[0044] Returning to FIG. 5, in step S4, the control unit 60 (see FIG. 1) transfers the semiconductor chip 1 by irradiating the semiconductor chip 1 and the transferee 20 with laser light L while applying an electrostatic attraction force to the semiconductor chip 1 and the transferee 20. Specifically, while applying an electrostatic attraction force to the semiconductor chip 1 and the transferee 20, the control unit 60 irradiates the transfer substrate 10, on which the semiconductor chip 1 is arranged, with the laser light L from the side opposite to the surface 10a of the transfer substrate 10 on which the semiconductor chip 1 is arranged (Z1 side) via the adhesive layer 2. The laser light L then penetrates the transfer substrate 10 and irradiates the adhesive layer 2, thereby peeling the semiconductor chip 1 from the transfer substrate 10 and transferring the semiconductor chip 1 from the transfer substrate 10 to the transferee 20. That is, the transfer is performed by the laser lift-off method. Note that, as shown in FIG. 4, the entire semiconductor chip 1 is peeled and transferred by intermittently irradiating the semiconductor chip 1 with laser light L having a spot area smaller than the area of ​​the semiconductor chip 1 multiple times. The situation during the transfer of the semiconductor chip 1 will be described later.

[0045] Returning to Fig. 5, in step S5, the control unit 60 (see Fig. 1) determines whether all of the semiconductor chips 1 arranged on the transfer substrate 10 have been transferred. If the answer is No in step S5, the process returns to step S4. If the answer is Yes in step S5, the process of the semiconductor chip transfer method ends.

[0046] (Situation during transfer of semiconductor chip) As shown in FIG. 10, when the adhesive layer 2 is irradiated with laser light L, the adhesive layer 2 is deformed into a convex shape that protrudes toward the Z2 side. The deformed portion B of the adhesive layer 2 pushes the semiconductor chip 1 in the Z2 direction, thereby peeling the semiconductor chip 1 from the adhesive layer 2. The semiconductor chip 1 pushed out by the deformed portion B of the adhesive layer 2 is subjected to adhesive forces F1, F2, F3, and F4, the weight G of the semiconductor chip 1 due to gravity, and an electrostatic attraction force C. Here, the adhesive forces F1, F2, F3, and F4 act in the direction toward the adhesive layer 2 (Z1 direction) and therefore hinder the transfer of the semiconductor chip 1. The weight G acts in the direction toward the transfer recipient 20 (Z2 direction), therefore assisting the transfer of the semiconductor chip 1. The electrostatic attraction force C acts in the direction toward the transfer recipient 20 (Z2 direction), therefore assisting the transfer of the semiconductor chip 1. When the sum of the weight G and the electrostatic attraction force C is greater than the sum of the adhesive forces F1, F2, F3, and F4, the semiconductor chip 1 is peeled off from the adhesive layer 2 and transferred. In other words, irradiating the semiconductor chip 1 and the transferred portion 20 with laser light L while applying electrostatic attraction force is particularly effective in peeling the semiconductor chip 1 from the adhesive layer 2, even when the weight G of the semiconductor chip 1 is relatively small, such as in the case of a semiconductor chip 1 with a relatively small thickness. The deformed portion B of the adhesive layer 2 is also called a blister.

[0047] (Effects of the first embodiment) Next, the effects of the first embodiment will be described.

[0048] As described above, the first embodiment includes a charging step of charging at least the transferred portion 20 of the semiconductor chip 1 and the transferred portion 20 arranged on the transfer substrate 10 via the adhesive layer 2, and a transfer step of irradiating laser light L toward the transfer substrate 10 from the side of the transfer substrate 10 opposite to the side on which the semiconductor chip 1 is arranged, with at least the transferred portion 20 of the semiconductor chip 1 and the transferred portion 20 being charged, thereby transferring the semiconductor chip 1 to the transferred portion 20. The charging step includes a step of charging at least the transferred portion 20 of the semiconductor chip 1 and the transferred portion 20 so that an electrostatic attraction force C acts on the semiconductor chip 1 and the transferred portion 20 in the transfer step. As a result, the electrostatic attraction force C acting on the semiconductor chip 1 acts to assist the peeling of the semiconductor chip 1 from the adhesive layer 2, so that the semiconductor chip 1 can be peeled from the adhesive layer 2 even in the case of a semiconductor chip 1 with a relatively small thickness.

[0049] Furthermore, in the first embodiment, as described above, the charging step includes a step of charging at least the surface of the transferred portion 20 facing the semiconductor chip 1 among the surfaces of the semiconductor chip 1 and the transferred portion 20 facing each other in the transfer step, and the transfer step includes a step of irradiating laser light L toward the transfer substrate 10 from the side opposite to the side on which the semiconductor chip 1 is placed, to transfer the semiconductor chip 1 to the transferred portion 20, while at least the surface of the transferred portion 20 facing the semiconductor chip 1 among the surfaces of the semiconductor chip 1 and the transferred portion 20 facing each other is charged. As a result, the distance between the charged surfaces of the semiconductor chip 1 and the transferred portion 20 becomes relatively small, and therefore the electrostatic attraction force C acting on the semiconductor chip 1 and the transferred portion 20 becomes relatively large. As a result, the relatively large electrostatic attraction force C acts to assist in the peeling of the semiconductor chip 1 from the adhesive layer 2, so that the semiconductor chip 1 can be easily peeled from the adhesive layer 2 even in the case of a semiconductor chip 1 having a relatively small thickness and therefore a relatively small weight G of the semiconductor chip 1.

[0050] Furthermore, in the first embodiment, as described above, the charging step includes a step of charging both the semiconductor chip 1 and the transferred portion 20 to polarities different from each other, and the transfer step includes a step of irradiating laser light L toward the transfer substrate 10 from the side of the transfer substrate 10 opposite to the side on which the semiconductor chip 1 is placed, in a state in which an electrostatic attraction force C is exerted on the semiconductor chip 1 and the transferred portion 20 by charging both the semiconductor chip 1 and the transferred portion 20 to polarities different from each other, thereby transferring the semiconductor chip 1 to the transferred portion 20. This allows the electrostatic attraction force C to be exerted on the semiconductor chip 1 and the transferred portion 20 more effectively.

[0051] Furthermore, in the first embodiment, as described above, the charging step includes at least the second charging step of: a first charging step in which a first charging unit 80a, which irradiates ions Ia to charge the semiconductor chip 1, is moved relative to the semiconductor chip 1 in a direction along the surface of the semiconductor chip 1 to irradiate ions Ia, and a second charging step in which a second charging unit 80b, which irradiates ions Ib to charge the transferred unit 20, is moved relative to the transferred unit 20 in a direction along the surface of the transferred unit 20 to irradiate ions Ib, and the second charging step includes at least the second charging step of: a first charging unit 80a, which irradiates ions Ia to charge the semiconductor chip 1, is moved relative to the transferred unit 20 in a direction along the surface of the transferred unit 20 to charge the transferred unit 20, which irradiates ions Ib, and the second charging step of charging the transferred unit 20. As a result, at least the transferred unit 20 out of the semiconductor chip 1 and the transferred unit 20 can be charged simply by moving the charging unit that irradiates ions. This makes it possible to easily peel the semiconductor chip 1 from the adhesive layer 2.

[0052] Furthermore, in the first embodiment, as described above, the first charging step includes a step of irradiating the semiconductor chip 1 with ions Ia while moving the first charging unit 80a relative to the semiconductor chip 1 in a direction along the surface of the semiconductor chip 1 from one end to the other end of the area where the semiconductor chip 1 is to be placed, thereby charging the semiconductor chip 1. The second charging step includes a step of irradiating the transferred unit 20 with ions Ib while moving the second charging unit 80b relative to the transferred unit 20 in a direction along the surface of the transferred unit 20 from one end to the other end of the area where at least the semiconductor chip 1 is to be placed, thereby charging the transferred unit 20. This allows at least the transferred unit 20, out of the semiconductor chip 1 and the transferred unit 20, to be charged over a wider area, thereby increasing the electrostatic attraction force C acting on the semiconductor chip 1 and the transferred unit 20. This allows the semiconductor chip 1 to be effectively peeled off from the adhesive layer 2.

[0053] [Second embodiment] Next, a semiconductor chip transfer method according to the second embodiment will be described. Unlike the first embodiment in which the semiconductor chip 1 and the transferred portion 20 are charged to different polarities, the semiconductor chip transfer method according to the second embodiment charges only the transferred portion 20.

[0054] The configuration of the semiconductor chip transfer device 100 of the second embodiment is similar to that of the first embodiment.

[0055] A semiconductor chip transfer method according to the second embodiment will be described with reference to Figures 1, 10 and 11. Note that a description of the same reference numerals as in the first embodiment will be omitted.

[0056] As shown in FIG. 11 , in the second embodiment, the control unit 60 (see FIG. 1 ) charges the transferred portion 20 to a positive polarity in step S21. The specific charging method for the transferred portion 20 is the same as in the first embodiment. Here, as shown in FIG. 10 , the semiconductor chip 1 is pushed out by the deformed portion B of the adhesive layer 2 and is charged by peeling when peeled off from the adhesive layer 2. In the second embodiment, the semiconductor chip 1 is formed of a material containing silicon, which is easily negatively charged by peeling, and therefore is negatively charged by peeling when peeled off from the adhesive layer 2. In other words, by charging the transferred portion 20 to a positive polarity, which is opposite to the polarity to which the semiconductor chip 1 is easily charged by peeling, an electrostatic attraction force C acts on the semiconductor chip 1 and the transferred portion 20. Note that the polarity to which the semiconductor chip 1 is easily charged by peeling is determined by comparing the materials of the semiconductor chip 1 and the adhesive layer 2 based on the triboelectric series.

[0057] 11, in step S41, the control unit 60 (see FIG. 1) irradiates the transferred portion 20 with laser light L while the transferred portion 20 is positively charged, thereby transferring the semiconductor chip 1. The specific method of irradiating the laser light L is the same as in the first embodiment.

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

[0059] In the second embodiment, as described above, the charging step includes a step of charging the transferred portion 20 to a polarity different from the polarity to which the semiconductor chip 1 is likely to be charged due to peeling charging, and the transfer step includes a step of irradiating the transferred portion 20 with laser light L from the side of the transfer substrate 10 opposite to the side on which the semiconductor chip 1 is placed, thereby transferring the semiconductor chip 1 to the transferred portion 20. This allows the semiconductor chip 1 and the transferred portion 20 to be charged to different polarities without actively charging the semiconductor chip 1, thereby allowing an electrostatic attraction force C to act on the semiconductor chip 1 and the transferred portion 20. As a result, the semiconductor chip 1 can be easily peeled off from the adhesive layer 2.

[0060] Furthermore, in the second embodiment, as described above, the charging step includes a step of charging the transferred portion 20 to a positive polarity that is different from the polarity to which the semiconductor chip 1 made of a material containing silicon is likely to be charged due to peeling charging, and the transfer step includes a step of irradiating the transferred portion 20 with laser light L from the side of the transfer substrate 10 opposite to the side on which the semiconductor chip 1 is placed, in a state in which the transferred portion 20 is charged to a positive polarity that is different from the polarity to which the semiconductor chip 1 made of a material containing silicon is likely to be charged due to peeling charging, thereby transferring the semiconductor chip 1 to the transferred portion 20. In this way, even for elements made of a material containing silicon, the semiconductor chip 1 and the transferred portion 20 can be charged to different polarities without actively charging the semiconductor chip 1, so that the electrostatic attraction force C can be easily exerted on the semiconductor chip 1 and the transferred portion 20.

[0061] [Variations] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than the above description of the embodiments, and further includes all modifications (variations) within the meaning and scope of the claims.

[0062] For example, in the first embodiment, an example was shown in which the mutually facing surfaces of the semiconductor chip 1 and the transferred part 20 were charged, but the present invention is not limited to this. For example, the side surfaces of the semiconductor chip 1 and the transferred part 20 may be charged. The side surfaces of the semiconductor chip 1 refer to the surface of the semiconductor chip 1 facing the transferred part 20 and any surface other than the surface of the semiconductor chip 1 facing the adhesive layer 2. Furthermore, the side surfaces of the transferred part 20 refer to the surface of the transferred part 20 facing the semiconductor chip 1 and any surface other than the surface of the transferred part 20 facing the transferred substrate holding part 40.

[0063] In the first and second embodiments, the charging unit 80 is configured to emit ions of positive or negative polarity by corona discharge, but the present invention is not limited to this. For example, the charging unit 80 may be charged by a method other than the method of emitting ions of positive or negative polarity by corona discharge.

[0064] Furthermore, in the first embodiment, an example was shown in which the charging unit 80 was charged while moving relative to the semiconductor chip 1 and the transferred unit 20, but the present invention is not limited to this. For example, the charging unit 80 does not need to be moved. In this case, only a portion of the semiconductor chip 1 and the transferred unit 20 may be charged, or the entire semiconductor chip 1 and the transferred unit 20 may be charged without moving the charging unit 80 by holding the charging unit 80 in a position where the entire semiconductor chip 1 and the transferred unit 20 can be charged.

[0065] In the first embodiment, the semiconductor chip 1 is negatively charged and the transferred portion 20 is positively charged, but the present invention is not limited to this. For example, the semiconductor chip 1 may be positively charged and the transferred portion 20 may be negatively charged. In this case, the semiconductor chip 1 is positively charged with a sufficient amount of charge so that the semiconductor chip 1 is not negatively charged due to peeling charging during transfer.

[0066] In the first embodiment, the first charging unit 80a and the second charging unit 80b are separate, but the present invention is not limited to this. For example, the first charging unit 80a and the second charging unit 80b may be a common unit that can switch the polarity of the ions it emits between negative and positive polarities.

[0067] In the first and second embodiments, the area SA of the spot region of the laser light is smaller than the area 1A of the semiconductor chip 1, but the present invention is not limited to this. For example, the area SA of the spot region of the laser light may be equal to or larger than the area 1A of the semiconductor chip 1.

[0068] In the first and second embodiments, the transfer substrate 10 has a circular shape and the transferred portion 20 has a rectangular shape, but the present invention is not limited to this. For example, the shapes of the transfer substrate 10 and the transferred portion 20 may both be circular or polygonal.

[0069] In the first and second embodiments, the intervals between the irradiation positions of the intermittently irradiated laser light L are uniform on the semiconductor chip 1, but 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.

[0070] Furthermore, in the first and second embodiments, the spot area of ​​the laser light L is rectangular, but the present invention is not limited to this. For example, the spot area of ​​the laser light L may be circular.

[0071] In the first and second embodiments, an example was shown in which a thin element such as a memory was used as the semiconductor chip 1, but the present invention is not limited to this. For example, various semiconductor elements other than a memory may be used as the semiconductor chip 1.

[0072] In the first and second embodiments, an example has been shown in which the common drive mechanism 50 is configured to be able to move the transfer substrate holding unit 30, the transferee substrate holding unit 40, and the charging unit 80, but the present invention is not limited to this. For example, the drive mechanism 50 may be provided separately for the transfer substrate holding unit 30, the transferee substrate holding unit 40, and the charging unit 80.

[0073] Furthermore, in the first embodiment, the length Da of the first charging portion 80a in a direction perpendicular to the direction in which the first charging portion 80a moves when charging the semiconductor chip 1 within a plane along the surface of the semiconductor chip 1 is equal to or greater than the length da of the area in which the semiconductor chip 1 is disposed. However, the present invention is not limited to this. For example, the length Da of the first charging portion 80a in a direction perpendicular to the direction in which the first charging portion 80a moves when charging the semiconductor chip 1 within a plane along the surface of the semiconductor chip 1 may be smaller than the length da of the area in which the semiconductor chip 1 is disposed. In this case, the entire semiconductor chip 1 can be charged by moving the first charging portion 80a back and forth multiple times between one end and the other end of the area in which the semiconductor chip 1 is disposed.

[0074] Furthermore, in the first and second embodiments, the length Db of the second charging portion 80b in the direction perpendicular to the direction in which the second charging portion 80b moves when charging the transferred portion 20 within a plane along the surface of the transferred portion 20 is equal to or greater than the length db of the transferred portion 20. However, the present invention is not limited to this. For example, the length Db of the second charging portion 80b in the direction perpendicular to the direction in which the second charging portion 80b moves when charging the transferred portion 20 within a plane along the surface of the transferred portion 20 may be smaller than the length db of the transferred portion 20. In this case, the entire transferred portion 20 can be charged by moving the second charging portion 80b back and forth between one end and the other end of the transferred portion 20 multiple times.

[0075] Although the first and second embodiments have described an example in which the second charging unit 80b is moved from one end to the other end of the transferee 20, the present invention is not limited thereto. For example, the second charging unit 80b may be moved from one end to the other end of a region of the transferee 20 corresponding to the region where the semiconductor chip 1 is to be placed. Here, the region of the transferee 20 corresponding to the region where the semiconductor chip 1 is to be placed refers to a region of the transferee 20 that overlaps with the region where the semiconductor chip 1 is to be placed when the semiconductor chip 1 is transferred, as viewed from the Z-axis direction. Furthermore, when the second charging unit 80b is moved from one end to the other end of the region of the transferee 20 corresponding to the region where the semiconductor chip 1 is to be placed, in order to improve the transfer position accuracy of the semiconductor chip 1, a region of the transferee 20 other than the region where the semiconductor chip 1 is to be placed may be charged to the same polarity as the polarity to which the semiconductor chip 1 is charged during transfer.

[0076] Furthermore, in the first and second embodiments, examples have been shown in which the laser output of the intermittently irradiated laser light L is the same for all laser beams, but the present invention is not limited to this. For example, the control unit 60 may be configured to adjust the laser output of the laser light L according to the degree of charge of the semiconductor chip 1 and the transferred unit 20. Specifically, the control unit 60 may be configured to relatively increase the laser output of the laser light L irradiated onto portions of the semiconductor chip 1 and the transferred unit 20 that are relatively lightly charged, and to relatively decrease the laser output of the laser light L irradiated onto portions of the semiconductor chip 1 and the transferred unit 20 that are relatively heavily charged.

[0077] In the second embodiment, the polarity to which the semiconductor chip 1 is likely to be charged by peeling electrification is negative, but the present invention is not limited to this. For example, the polarity to which the semiconductor chip 1 is likely to be charged by peeling electrification may be positive. The polarity to which the semiconductor chip 1 is likely to be charged by peeling electrification is determined by comparing the materials of the semiconductor chip 1 and the adhesive layer 2 based on the triboelectric series.

[0078] In the first and second embodiments, the peeling of the semiconductor chip 1 from the adhesive layer 2 is assisted by charging at least the transferred portion 20 out of the semiconductor chip 1 and the transferred portion 20, but the present invention is not limited to this. For example, the peeling of the semiconductor chip 1 from the adhesive layer 2 may be assisted by stretching the adhesive layer 2, which has elasticity. [Explanation of symbols]

[0079] 1. Semiconductor chip (element) 2 Adhesive layer 10 Transfer substrate (first substrate) 20 Transferred part (second substrate) 30 Transfer substrate holding unit (first substrate holding unit) 70 Laser light irradiation unit 80 Charging section 80a First charging section 80b Second charging section 100 Semiconductor chip transfer device (element transfer device) L laser light Ia negative polarity ions (ions) Ib Positive polarity ions (ions) C Electrostatic attraction force D. Predetermined interval

Claims

1. a charging step of charging at least the second substrate out of the element disposed on the first substrate via the adhesive layer and the second substrate; a transfer step of irradiating a laser beam onto the first substrate from a side of the first substrate opposite to a side on which the elements are arranged, while at least the second substrate out of the elements and the second substrate is charged, thereby transferring the elements onto the second substrate; The element transfer method, wherein the charging step includes a step of charging at least the second substrate out of the element and the second substrate so that an electrostatic attraction force acts on the element and the second substrate in the transfer step.

2. the charging step includes a step of charging at least a surface of the second substrate facing the element among surfaces of the element and the second substrate facing each other in the transfer step, 2. The element transfer method according to claim 1, wherein the transfer step includes a step of irradiating the laser light toward the first substrate from a side opposite to the side on which the element of the first substrate is arranged, while charging at least the surface of the second substrate facing the element, of the surfaces of the element and the second substrate facing each other.

3. the charging step includes a step of charging the second substrate to a polarity different from a polarity to which the elements are likely to be charged by peeling charging, 2. The element transfer method according to claim 1, wherein the transfer step includes a step of irradiating the laser light toward the first substrate from the side opposite to the side on which the element is arranged on the first substrate, while charging the second substrate with a polarity different from the polarity to which the element is likely to be charged by peeling charging, thereby transferring the element to the second substrate.

4. the charging step includes a step of charging the second substrate to a positive polarity that is different from a polarity to which the elements formed of a material containing silicon are likely to be charged by peeling charging, 2. The element transfer method according to claim 1, wherein the transfer step includes a step of irradiating the laser light toward the first substrate from the side opposite to the side on which the elements of the first substrate are arranged, while charging the second substrate with a positive polarity that is different from the polarity to which the elements formed from a material containing silicon are likely to be charged by peeling charging, thereby transferring the elements to the second substrate.

5. the charging step includes a step of charging both the element and the second substrate to polarities opposite to each other; 2. The element transfer method according to claim 1, wherein the transfer step includes a step of irradiating a laser beam toward the first substrate from a side of the first substrate opposite to the side on which the element is arranged, while applying an electrostatic attraction force to the element and the second substrate by charging both the element and the second substrate with polarities different from each other, thereby transferring the element to the second substrate.

6. 2. The element transfer method according to claim 1, wherein the charging step includes at least a first charging step of irradiating ions to charge the element while moving a first charging unit that irradiates ions to charge the element relative to the element in a direction along the surface of the element, and a second charging step of irradiating ions to charge the second substrate while moving a second charging unit that irradiates ions to charge the second substrate relative to the second substrate in a direction along the surface of the second substrate.

7. the first charging step includes a step of irradiating ions onto the elements while moving the first charging unit relative to the elements in a direction along the surface of the elements from one end to the other end of an area in which the elements are arranged, thereby charging the elements; 7. The element transfer method according to claim 6, wherein the second charging step includes a step of charging the second substrate by irradiating ions while moving the second charging unit relative to the second substrate in a direction along the surface of the second substrate from one end to the other end of an area corresponding to at least an area in which the element is arranged.

8. a first substrate holding section that holds the first substrate on which the elements are arranged via an adhesive layer so that the elements and the second substrate are spaced apart by a predetermined distance; a charging unit that charges at least the second substrate out of the element and the second substrate; a laser light irradiation unit that irradiates laser light toward the first substrate from a side of the first substrate opposite to a side on which the element is arranged, the laser light irradiation unit is configured to irradiate the laser light toward the first substrate while charging at least the second substrate out of the element and the second substrate so that an electrostatic attraction force acts on the element and the second substrate when the element is transferred, thereby transferring the element to the second substrate.

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