Transfer method and method for manufacturing receptor substrate

Abstract

To provide a laser lift-off method capable of suppressing an occurrence of a damage to a transfer object at the time of transfer.SOLUTION: A laser lift-off method for transferring a transfer object 10 from a first substrate 1 provided with the transfer object 10 to a second substrate by a laser lift-off, comprises a batch transfer step of collectively irradiating an interface 11 between the plurality of transfer objects 10 and the first substrate 1 with a laser 20 to peel the plurality of transfer objects 10 off from the first substrate 1 and collectively transferring the transfer objects to the second substrate. In the batch transfer step, only a part of the interface 11 between the plurality of transfer objects 10 and the first substrate 1 is irradiated with the laser 20.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a laser lift-off method, a method for manufacturing a receptor substrate, a laser lift-off apparatus, and a photomask. [Background technology]

[0002] In recent years, nitride semiconductor optical devices have come to be used as backlights for liquid crystal displays and signage displays.

[0003] Optical devices are mass-produced on sapphire substrates, for example, using semiconductor processes. To produce a 4-inch display substrate using LEDs called micro LEDs, which are 100 μm square or less, several million micro LEDs are required. Micro LEDs, which are tiny devices measuring several tens of μm, are used after being separated from the sapphire substrate, which is the epitaxial substrate.

[0004] The common separation method is to bond a support substrate as a donor precursor substrate to the optical devices arranged on a sapphire substrate, and then separate the optical devices from the sapphire substrate by laser lift-off (LLO), thereby obtaining a donor substrate with a large number of optical devices arranged on its surface.

[0005] Such a method is not limited to optical devices, but can also be applied to manufacturing a donor substrate having a plurality of transfer objects, such as minute semiconductor devices, arranged on its surface.

[0006] In addition, the object to be transferred on the donor substrate can be transferred onto a receptor substrate so that it is arranged in a manner corresponding to the circuit board of the product, and then transferred from this receptor substrate to another substrate, such as the circuit board of the product, using a stamping method.

[0007] For example, Patent Document 1 proposes a method for transferring an object to be transferred from a donor substrate to a receptor substrate with high precision using laser irradiation.

[0008] Now, the laser lift-off method is a technology in which a substrate (first substrate) having an object to be transferred is irradiated with a laser at the interface between the object to be transferred and the first substrate, thereby peeling the object from the first substrate and transferring the peeled object to another substrate (second substrate).

[0009] Such laser lift-off methods are roughly divided into gap-laser lift-off (Gap-LLO) and contact laser lift-off (Contact-LLO). These methods will be briefly described below with reference to FIGS. 21 and 22.

[0010] In Gap-LLO, first, as shown in FIG. 21(a), for example, a first substrate (e.g., a sapphire substrate) 1 having transfer objects (e.g., micro LED chips) 10 and a second substrate (e.g., a quartz substrate) 2 having an adhesive layer 3 on its surface are placed opposite each other with a space between the transfer objects 10 and the adhesive layer 3, i.e., a gap being provided. In this state, a laser 20R is emitted from a laser oscillator 110 through the surface of the first substrate 1 opposite to the transfer objects 10, onto interfaces 11 between the first substrate 1 and the multiple transfer objects 10. The laser 20R is generally irradiated onto the entire surface of the interface 11 between the first substrate 1 and each of the transfer objects 10 one by one in sequence.

[0011] For example, in the case of the first substrate 1 being a sapphire substrate provided with a plurality of transfer objects 10 including a GaN layer at the interface 11, the GaN layer is decomposed (ablated) by irradiation with the laser 20R. When the bonding strength (adhesive strength, bonding strength, etc.) between the transfer objects 10 and the first substrate 1 is weakened by the ablation, the transfer objects 10 are peeled off from the first substrate 1. In addition, gas (e.g., nitrogen gas) is generated by the decomposition of the GaN layer. The pressure of this gas provides a driving force for the peeled transfer objects 10 toward the second substrate 2, causing them to move through the space between the first substrate 1 and the second substrate 2 and reach the adhesive layer 3 on the second substrate 2. In this manner, the transfer objects 10 are transferred onto the second substrate 2.

[0012] 21(b), the first substrate 1 is removed, thereby completing the transfer of the transfer object 10 from the first substrate 1 to the second substrate 2.

[0013] Contact-LLO is similar to Gap-LLO except that, during irradiation with laser 20R, as shown in Fig. 22(a), a first substrate 1 having a transfer object 10 and a second substrate 2 having an adhesive layer 3 on its surface are opposed to each other with the transfer object 10 and the adhesive layer 3 in contact with each other. After irradiation with laser 20R, the first substrate 1 is removed as shown in Fig. 22(b), thereby completing the transfer of the transfer object 10 from the first substrate 1 to the second substrate 2. [Prior art documents] [Patent documents]

[0014] [Patent Document 1] Japanese Patent Application Publication No. 2020-4478 Summary of the Invention [Problem to be solved by the invention]

[0015] Previously, when transferring using Gap-LLO, the transferred object could break. Even with Contact-LLO, the transferred object could sometimes be chipped.

[0016] The present invention has been made to solve the above problems, and aims to provide a laser lift-off method that can prevent damage to an object to be transferred during transfer, a method for manufacturing a receptor substrate that can produce a receptor substrate equipped with a damage-free object to be transferred, a laser lift-off apparatus that can prevent damage to an object to be transferred during transfer, and a photomask for laser lift-off that can prevent damage to an object to be transferred during transfer. [Means for solving the problem]

[0017] In order to solve the above-mentioned problems, the present invention provides a laser lift-off method for transferring an object from a first substrate having the object thereon to a second substrate by laser lift-off, the method comprising: a batch transfer step of irradiating interfaces between the plurality of transfer objects and the first substrate with a laser at the same time, thereby peeling the plurality of transfer objects from the first substrate and transferring them at the same time to the second substrate; In the collective transfer step, the laser lift-off method is provided, in which the laser is irradiated onto only a part of the interface between each of the plurality of transfer objects and the first substrate.

[0018] Here, "laser irradiation only partially" means that the laser irradiation at each interface is only partially irradiated at each interface. In other words, it is sufficient that the laser irradiation at each interface is only partially irradiated at each interface, and simultaneously with this irradiation, laser irradiation may be performed on an area where no transfer object is present. Therefore, the present invention also includes forms in which the laser is irradiated even on an area where no transfer object is present, such as between adjacent transfer objects, as illustrated in Figures 4, 5, and 6 described below.

[0019] In the batch transfer process, by irradiating the laser only to a portion of the interface between each of the multiple transfer objects and the first substrate (hereinafter also referred to as partial irradiation), the impact that occurs during laser lift-off can be reduced, and damage such as cracking and chipping of the transfer objects during transfer can be suppressed.

[0020] It is preferable that the method further includes a preliminary irradiation step, prior to the batch transfer step, of irradiating the interface between each of the plurality of transfer objects and the first substrate with a laser at an energy level that is lower than the energy irradiated in the batch transfer step and that does not cause the transfer objects to peel off from the first substrate.

[0021] By performing such a preliminary irradiation process, it is possible to further reduce the impact on the objects to be transferred in the batch transfer process, and to suppress the transfer position deviation of the objects to be transferred. Furthermore, in the batch transfer process, when a material having a crystalline structure such as a GaN layer is used as the ablation layer, it is possible to suppress the occurrence of cleavage and the occurrence of residues.

[0022] In this case, it is particularly preferable that in the preliminary irradiation step, the laser be irradiated only onto a portion of the interface between each of the plurality of transfer objects and the first substrate.

[0023] By performing partial irradiation in the preliminary irradiation step as well, when a material having a crystalline structure such as a GaN layer is used as the ablation layer, the occurrence of cleavage can be further suppressed, and therefore the occurrence of residues can be suppressed.

[0024] For example, the preliminary irradiation step can be carried out 1 to 4 times.

[0025] The number of times the preliminary irradiation step is performed is not particularly limited, but by performing the step multiple times, it becomes easier to control the impact on the object to be transferred during laser lift-off while maintaining an appropriate laser lift-off speed.

[0026] For example, in each of the preliminary irradiation process and the collective transfer process, it is preferable to perform laser irradiation so that the laser irradiation area is 10 to 60% of the area of ​​the interface between each of the multiple transfer objects and the first substrate.

[0027] If the irradiation area in the partial irradiation in each of the preliminary irradiation process and the batch transfer process is within the range of 10 to 60% of the area of ​​the interface between each of the multiple transfer objects and the first substrate, the transfer objects can be efficiently transferred from the first substrate to the second substrate, and a tolerance can be provided for laser irradiation errors.

[0028] It is preferable that the laser irradiation area be changed between the preliminary irradiation step and the collective transfer step.

[0029] By changing the laser irradiation area between the preliminary irradiation process and the batch transfer process, the occurrence of unirradiated areas between the object to be transferred and the first substrate can be suppressed, and the occurrence of cleavage areas can be suppressed when a material with a crystalline structure such as a GaN layer is used as the ablation layer.

[0030] It is preferable that the preliminary irradiation process and the collective transfer process are carried out so that there is no overlapping portion of the laser irradiation area, or so that the overlapping portion of the laser irradiation area is 10% or less of the area of ​​the interface between each of the multiple transfer objects and the first substrate.

[0031] The irradiation areas in the preliminary irradiation process and the batch transfer process may overlap, and by keeping the overlapping area to 10% or less, excessive deterioration of the objects to be transferred can be suppressed and a margin for laser irradiation error can be provided.

[0032] In the preliminary irradiation step and the collective transfer step, the laser can be irradiated onto 40 to 100% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate.

[0033] More efficient transfer can be achieved by irradiating the laser onto 40% or more of the area of ​​the interface between each of the plurality of transfer objects and the first substrate in the preliminary irradiation step and the batch transfer step combined. Alternatively, the laser may be irradiated onto the entire area of ​​the interface between each of the plurality of transfer objects and the first substrate, i.e., 100%, in the preliminary irradiation step and the batch transfer step combined.

[0034] For example, the output of the laser may be changed between the preliminary irradiation step and the collective transfer step.

[0035] For example, by changing the laser output between the preliminary irradiation step and the collective transfer step, the laser irradiation energy in the preliminary irradiation step can be made smaller than the irradiation energy in the collective transfer step.

[0036] Alternatively, a photomask including a first portion having a first laser transmittance and a second portion having a second laser transmittance lower than the first laser transmittance is provided; In the preliminary irradiation step, the laser is irradiated through the second portion of the photomask, In the collective transfer step, the laser may be irradiated through the first portion of the photomask.

[0037] This is advantageous for mass production, since there is no need to change the laser output between the preliminary irradiation step and the batch transfer step.

[0038] In the collective transfer step, it is preferable that the laser irradiation be performed so that the laser irradiation area occupies 40 to 90% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate.

[0039] If the area of ​​the laser irradiation region in the batch transfer step is within the above range, it is possible to prevent damage to the objects to be transferred while maintaining transfer efficiency.

[0040] In the collective transfer step, the laser may be irradiated onto the interface between each of the plurality of transfer objects and the first substrate so that a plurality of irradiation regions onto which the laser is irradiated are formed.

[0041] The form of partial irradiation is not particularly limited, but for example, a plurality of irradiation regions may be formed.

[0042] In this case, for example, in the collective transfer step, the laser can be irradiated so that the irradiation area has at least one shape selected from the group consisting of a circle, an ellipse, and a polygon.

[0043] The shape of the irradiation area is not particularly limited, but may be, for example, a circle, an ellipse, or a polygon.

[0044] Alternatively, in the collective transfer step, the laser can be irradiated so that the irradiation area has a line shape.

[0045] The illumination area may be in the shape of a line.

[0046] For example, in the batch transfer process, the laser can be irradiated so that the irradiation area has a rectangular or linear shape and the longitudinal direction of the irradiation area approximately coincides with the longitudinal direction of the object to be transferred.

[0047] Alternatively, in the batch transfer process, the irradiation area may have a rectangular or linear shape, and the laser may be irradiated so that the longitudinal direction of the irradiation area and the lateral direction of the object to be transferred approximately coincide with each other.

[0048] Alternatively, in the collective transfer step, the irradiation area may have a rectangular or linear shape, and the laser may be irradiated so that the irradiation area straddles the adjacent objects to be transferred.

[0049] In this way, the arrangement of the multiple irradiation areas on the transfer object is not particularly limited.

[0050] In the batch transfer process, the laser can be irradiated to the interface between each of the plurality of transfer objects and the first substrate so that a plurality of non-irradiated regions where the laser is not irradiated are formed.

[0051] Partial irradiation may be performed so that multiple non-irradiated areas are formed.

[0052] In this case, for example, in the collective transfer step, the laser can be irradiated so that the non-irradiated region has at least one shape selected from the group consisting of a circle, an ellipse, and a polygon.

[0053] The shape of the non-irradiated region is not particularly limited, but may be, for example, a circle, an ellipse, or a polygon.

[0054] Alternatively, in the collective transfer step, the laser may be irradiated so that the non-irradiated region has a line shape.

[0055] The non-irradiated area may be in the shape of a line.

[0056] For example, in the batch transfer process, the laser can be irradiated so that the non-irradiated area has a rectangular or linear shape and the longitudinal direction of the non-irradiated area approximately coincides with the longitudinal direction of the object to be transferred.

[0057] Alternatively, in the batch transfer process, the non-irradiated area may have a rectangular or linear shape, and the laser may be irradiated so that the longitudinal direction of the non-irradiated area and the short direction of the object to be transferred approximately coincide with each other.

[0058] Alternatively, in the collective transfer step, the non-irradiation area may have a rectangular or linear shape, and the laser may be irradiated so that the non-irradiation area straddles the adjacent objects to be transferred.

[0059] In this way, the arrangement of the plurality of non-irradiation areas on the transfer object is not particularly limited.

[0060] For example, the object to be transferred may be an object selected from the group consisting of a semiconductor chip, an LED chip, a resin material film, and an inorganic film.

[0061] The object to be transferred in the present invention is not particularly limited, but for example, the following items can be used as the object to be transferred.

[0062] The present invention also provides a method for manufacturing a receptor substrate on which a plurality of transfer objects are arranged, comprising the steps of: preparing a donor substrate having the plurality of transfer objects and a receptor precursor substrate; transferring the object from the donor substrate to the receptor precursor substrate by laser lift-off to obtain a receptor substrate; Including, The present invention provides a method for manufacturing a receptor substrate, in which, in the step of obtaining the receptor substrate, laser lift-off is performed from the donor substrate as the first substrate to the receptor precursor substrate as the second substrate by the laser lift-off method of the present invention.

[0063] The method for producing a receptor substrate of the present invention involves transferring a transfer object using the laser lift-off method of the present invention to obtain a receptor substrate, which allows the production of a receptor substrate with an undamaged transfer object, and also improves the yield of receptor substrate production.

[0064] Further, the present invention provides a laser lift-off apparatus for transferring an object from a first substrate having the object thereon to a second substrate by laser lift-off, the apparatus comprising: a laser oscillator; a stage that supports the first substrate and the second substrate so that they face each other; a photomask disposed in an optical path between the laser oscillator and the stage; Equipped with the laser oscillator, the photomask, and the stage are configured to collectively irradiate interfaces between the plurality of transfer objects and the first substrate with a laser from the laser oscillator; The photomask has a pattern that shapes the laser from the laser oscillator so that it irradiates only a portion of the interface between each of the plurality of transfer objects and the first substrate.

[0065] The laser lift-off device of the present invention can partially irradiate each of the multiple objects when transferring them all at once to a second substrate by laser lift-off, thereby reducing the impact generated during laser lift-off and suppressing damage such as cracking and chipping of the objects during transfer.

[0066] It is preferable that the laser is further configured to be able to switch the energy irradiated to the interface between the multiple transfer objects and the first substrate between energy that does not cause the transfer objects to peel off from the first substrate and energy that does cause the transfer objects to peel off from the first substrate.

[0067] By using such an apparatus, partial irradiation can be performed in multiple stages, and the impact on the transfer objects can be further reduced when multiple transfer objects are transferred collectively to a second substrate by laser lift-off. Furthermore, when multiple transfer objects are transferred collectively to a second substrate by laser lift-off, if a material having a crystalline structure such as a GaN layer is used as the ablation layer, the generation of cleavage can be suppressed, and the generation of residue can be suppressed.

[0068] In this case, for example, the pattern of the photomask includes a first pattern and a second pattern, the laser is irradiated through the first pattern at the same time to the interfaces between the plurality of transfer objects and the first substrate with the energy sufficient to peel the transfer objects from the first substrate; and The laser can be further configured to be able to irradiate the interfaces between the multiple transfer objects and the first substrate simultaneously through the second pattern with energy that will not cause the transfer objects to peel off from the first substrate.

[0069] Such a laser lift-off apparatus can perform partial irradiation in multiple stages without changing the laser output.

[0070] Further, in the present invention, as a photomask of a first aspect, there is provided a photomask used in a laser lift-off method for transferring a transfer object from a first substrate having the transfer object to a second substrate by laser lift-off, The laser beam is irradiated simultaneously onto the interface between each of the plurality of transfer objects and the first substrate, A photomask is provided that has a pattern for shaping the laser so that only a portion of the interface between each of the plurality of transfer objects and the first substrate becomes an irradiation area.

[0071] Here, "only a portion of the irradiated area" means that the laser irradiated area at each interface is a part of the interface. In other words, the laser irradiated area at each interface only needs to be a part of the interface, and in addition to this irradiated area, areas where no transfer objects are present may also be included in the pattern. Therefore, the present invention also includes patterns in which the laser is irradiated even to areas where no transfer objects are present, such as between adjacent transfer objects, as shown in Figures 4, 5, and 6, which will be described later.

[0072] By using such a photomask, when multiple objects are transferred to a second substrate at once by laser lift-off, it is possible to partially irradiate each of the multiple objects, thereby reducing the impact generated during laser lift-off and suppressing damage such as cracking and chipping of the objects during transfer.

[0073] For example, the pattern may be configured to shape the laser so that a plurality of the irradiation regions are formed.

[0074] Alternatively, the pattern can be configured to shape the laser so that multiple non-irradiated areas are formed at the interface between each of the multiple transfer objects and the first substrate, where the laser is not irradiated.

[0075] As described above, the pattern of the photomask according to the first aspect of the present invention may be one that forms a plurality of irradiated regions, or one that forms a plurality of non-irradiated regions.

[0076] a first portion having the pattern formed therein and having a first laser transmittance; a second portion having a second laser transmissivity lower than the first laser transmissivity; It may have the following structure.

[0077] The photomask of the first aspect of the present invention may include two or more portions having different laser transmittances. By using such a photomask, it is possible to change the energy of the laser irradiated onto the interface between each of the plurality of transfer objects and the first substrate without changing the laser output.

[0078] Further, in the present invention, there is provided a photomask according to a second aspect, which is a photomask used in a laser lift-off method for transferring a transfer object from a first substrate having the transfer object to a second substrate by laser lift-off, a first portion having a pattern formed thereon for shaping an received laser beam into the pattern and having a first laser transmittance; a second portion having a second laser transmissivity lower than the first laser transmissivity; A photomask having the following structure is provided.

[0079] With the photomask according to the second aspect of the present invention, when multiple objects are collectively transferred to a second substrate by laser lift-off, each of the objects can be partially irradiated, thereby reducing the impact generated during laser lift-off and suppressing damage such as cracking and chipping of the objects during transfer.

[0080] Furthermore, by using such a photomask, it is possible to change the energy of the laser irradiated onto the interface between each of the multiple transfer objects and the first substrate without changing the laser output. Therefore, it is not necessary to provide multiple laser oscillators in one laser lift-off apparatus, to perform two laser irradiation operations with different laser outputs of the laser oscillators in one laser lift-off apparatus, or to prepare two laser lift-off apparatuses with different laser outputs of the laser oscillators, and it is possible to perform laser irradiation at multiple levels of laser output in a single laser irradiation operation. [Effects of the Invention]

[0081] As described above, the laser lift-off method of the present invention can prevent damage to the object to be transferred during transfer.

[0082] Furthermore, the method for producing a receptor substrate of the present invention makes it possible to produce a receptor substrate having an object to be transferred without damage.

[0083] Furthermore, the laser lift-off apparatus of the present invention can perform a laser lift-off method that can suppress damage to the object to be transferred during transfer.

[0084] The photomask of the present invention can be used as a photomask for laser lift-off, which can suppress damage to an object to be transferred during transfer. [Brief explanation of the drawings]

[0085] [Figure 1] 1 is a schematic diagram showing a first example of a laser lift-off apparatus according to the present invention. FIG. [Figure 2] FIG. 10 is a schematic diagram showing a second example of the laser lift-off apparatus of the present invention. [Figure 3] 1 is a schematic diagram showing a collective transfer step in an example of the laser lift-off method of the present invention. FIG. [Figure 4] 1A to 1C are schematic diagrams showing some forms of partial irradiation in the collective transfer step of the laser lift-off method of the present invention. [Figure 5] 3A to 3C are schematic diagrams showing some examples of photomask patterns used in the laser lift-off method of the present invention. [Figure 6] 3A to 3C are schematic diagrams showing some examples of photomask patterns used in the laser lift-off method of the present invention. [Figure 7] 1A to 1C are schematic diagrams illustrating a preliminary irradiation step and a collective transfer step in an example of the laser lift-off method of the present invention. [Figure 8] 8 is a photograph of the first substrate after the transfer object has been transferred in the preliminary irradiation step and the collective transfer step shown in FIG. 7. [Figure 9]4 is a photograph of the first substrate after the objects to be transferred have been transferred in the batch transfer process shown in FIG. 3. [Figure 10] FIG. 4 is a schematic diagram showing the mechanism of the collective transfer step shown in FIG. 3. [Figure 11] 8 is a schematic diagram showing the mechanism of the preliminary irradiation step and the collective transfer step shown in FIG. 7. FIG. [Figure 12] 10A to 10C are schematic diagrams illustrating a preliminary irradiation step and a collective transfer step in another example of the laser lift-off method of the present invention. [Figure 13] 13 is an enlarged view of a portion XIII of the photomask shown in FIG. 12. [Figure 14] 10A to 10C are schematic diagrams illustrating a preliminary irradiation step and a collective transfer step in another example of the laser lift-off method of the present invention. [Figure 15] FIG. 15 is an enlarged view of a portion XV of the photomask shown in FIG. [Figure 16] 10A to 10C are schematic diagrams illustrating a preliminary irradiation step and a collective transfer step in another example of the laser lift-off method of the present invention. [Figure 17] FIG. 17 is an enlarged view of a portion XVII of the photomask shown in FIG. [Figure 18] FIG. 2 is a schematic diagram showing the arrangement of an object to be transferred and a photomask in an example of the laser lift-off method of the present invention. [Figure 19] FIG. 19 is a schematic diagram showing an example of an irradiated region when partial irradiation is performed using the photomask shown in FIG. [Figure 20] 1 is a photograph of the first substrate after being transferred in Example 1. [Figure 21] FIG. 1 is a schematic diagram illustrating a conventional Gap-LLO. [Figure 22] FIG. 1 is a schematic diagram illustrating a conventional Contact-LLO. DETAILED DESCRIPTION OF THE INVENTION

[0086] As described above, there has been a demand for the development of a laser lift-off method capable of suppressing damage to the transfer object during transfer, a method for manufacturing a receptor substrate capable of manufacturing a receptor substrate having a transfer object without damage, a laser lift-off apparatus capable of suppressing damage to the transfer object during transfer, and a photomask for laser lift-off capable of suppressing damage to the transfer object during transfer.

[0087] As a result of extensive research into the above-mentioned problems, the inventors have found that, in transfer by laser lift-off, a bulk transfer process is adopted in which multiple objects to be transferred are transferred at once by laser lift-off, and in this bulk transfer process, by irradiating the laser only to a portion of the interface between each of the multiple objects to be transferred and the first substrate, it is possible to suppress the transfer position shift of the objects to be transferred that occurs during laser lift-off, and to reduce the impact that occurs during laser lift-off, thereby suppressing the occurrence of damage such as cracks and chips to the objects to be transferred during transfer, and have completed the present invention.

[0088] That is, the present invention is a laser lift-off method for transferring an object from a first substrate having the object to a second substrate by laser lift-off, the method comprising: a batch transfer step of irradiating interfaces between the plurality of transfer objects and the first substrate with a laser at the same time, thereby peeling the plurality of transfer objects from the first substrate and transferring them at the same time to the second substrate; In the collective transfer step, the laser lift-off method irradiates the laser onto only a portion of the interface between each of the plurality of transfer objects and the first substrate.

[0089] The present invention also provides a method for manufacturing a receptor substrate on which a plurality of transfer objects are arranged, comprising the steps of: preparing a donor substrate having the plurality of transfer objects and a receptor precursor substrate; transferring the object from the donor substrate to the receptor precursor substrate by laser lift-off to obtain a receptor substrate; Including, In the step of obtaining the receptor substrate, the method for manufacturing a receptor substrate includes laser lift-off of the plurality of transfer objects from the donor substrate as the first substrate to the receptor precursor substrate as the second substrate using the laser lift-off method of the present invention.

[0090] The present invention also provides a laser lift-off apparatus for transferring an object from a first substrate having the object thereon to a second substrate by laser lift-off, the apparatus comprising: a laser oscillator; a stage that supports the first substrate and the second substrate so that they face each other; a photomask disposed in an optical path between the laser oscillator and the stage; Equipped with the laser oscillator, the photomask, and the stage are configured to collectively irradiate interfaces between the plurality of transfer objects and the first substrate with a laser from the laser oscillator; The photomask is a laser lift-off device having a pattern that shapes the laser from the laser oscillator so that it irradiates only a portion of the interface between each of the multiple transfer objects and the first substrate.

[0091] The present invention also provides a photomask for use in a laser lift-off method for transferring an object from a first substrate having the object to a second substrate by laser lift-off, the photomask comprising: The laser beam is irradiated simultaneously onto the interface between each of the plurality of transfer objects and the first substrate, The photomask has a pattern for shaping the laser so that only a portion of the interface between each of the plurality of transfer objects and the first substrate becomes an irradiation area.

[0092] The present invention also provides a photomask for use in a laser lift-off method for transferring a transfer object from a first substrate having the transfer object to a second substrate by laser lift-off, the photomask comprising: a first portion having a pattern formed thereon for shaping an received laser beam into the pattern and having a first laser transmittance; a second portion having a second laser transmissivity lower than the first laser transmissivity; The photomask has the following structure.

[0093] The present invention will be described in detail below, but the present invention is not limited thereto.

[0094] [Laser lift-off equipment] FIG. 1 shows a schematic diagram of a first example of the laser lift-off apparatus of the present invention.

[0095] The laser lift-off apparatus 100 shown in FIG. 1 is an apparatus configured to perform Gap-LLO.

[0096] The laser lift-off apparatus 100 includes a laser oscillator 110, a stage 160, and a photomask 130. The laser lift-off apparatus 100 further includes, as optional components, a shaping optical system 120, a folding mirror 140, a reduction projection lens 150, an alignment camera 170, and a controller 180.

[0097] The stage 160 is composed of an upper stage 161 having an opening 161a and supporting the first substrate 1, and a lower stage 162 supporting the second substrate 2. The first substrate 1 is equipped with a plurality of transfer objects 10, similar to the first substrate 1 shown in Figures 21(a) and 22(a). The stage 160 is configured to support the first substrate 1 and the second substrate 2 facing each other.

[0098] The laser oscillator 110 is configured to emit a laser beam 20a. In the laser lift-off apparatus 100, the laser beam 20a emitted from the laser oscillator 110 passes through a shaping optical system 120 to be shaped into a laser beam 20b, the laser beam 20b passes through a photomask 130 to be shaped into a laser beam 20c, the direction of travel of the laser beam 20c is changed by a folding mirror 140, and the laser beam 20 passes through a reduction projection lens 150 to become a laser beam 20, and this laser beam 20 passes through an opening 161a in an upper stage 161 to form an optical path that reaches the first substrate 1. In other words, the photomask 130 is disposed between the laser oscillator 110 and the stage 160 in the optical path.

[0099] In the laser lift-off apparatus 100 shown in FIG. 1, the laser oscillator 110, the photomask 130, and the stage 160 (upper stage 161 and lower stage 162) are configured to irradiate the laser 20 from the laser oscillator 110 simultaneously onto the interfaces between multiple transfer objects 10 and the first substrate 1.

[0100] The optical path of the laser emitted from the laser oscillator 110 will now be described.

[0101] The laser 20a emitted from the laser oscillator 110 is, for example, an excimer laser.

[0102] The optional shaping optical system 120 shapes the irradiation shape of the laser 20a emitted from the laser oscillator 110, for example, as shown in Fig. 1(a), into a rectangular irradiation shape, for example, as shown in Fig. 1(b), and emits it as laser 20b. The laser 20b having a rectangular irradiation shape can exhibit a uniform irradiation energy density, for example, a beam profile exhibiting a top hat shape. However, the laser shaping by the shaping optical system 120 is not limited to this.

[0103] The photomask 130 is configured to shape the irradiation shape of the incident laser 20b into a pattern as shown in Fig. 1(c) and emit it as laser 20c. More specifically, the photomask 130 has a pattern that shapes the laser from the laser oscillator 110 into a shape that irradiates only a portion of the interface between each of the multiple transfer objects 10 and the first substrate 1. The photomask 130 is also configured to irradiate the received laser simultaneously onto the interface between each of the multiple transfer objects 10 and the first substrate 1, and can also be said to have a pattern that shapes the laser so that only a portion of the interface between each of the multiple transfer objects 10 and the first substrate 1 becomes an irradiation area.

[0104] The photomask 130 may further have a pattern formed into a shape that irradiates the entire surface of the interface between each of the plurality of transfer objects 10 and the first substrate 1. Other details of the photomask 130 will be described later.

[0105] The laser beam 20c emitted from the photomask 130 has its direction of travel changed by a folding mirror 140 and enters a reduction projection lens 150. The reduction projection lens 150 reduces the irradiation shape of the incident laser beam 20c, for example, from that shown in FIG. 1(d) to that shown in FIG. 1(e), and emits the laser beam 20.

[0106] By incorporating the reduction projection lens 150 into the optical path, the energy of the laser 20b incident on the photomask 130 can be made smaller than the energy required to peel the transfer object 10 from the first substrate 1. If the reduction magnification of the reduction projection optical lens 150 is N, the energy of the laser 20b incident on the photomask 130 is 1 / (N 2) This prevents deterioration of the shaping optical system 120 and the photomask 130 due to laser irradiation, and also suppresses thermal drift due to the energy of the laser 20b, thereby suppressing thermal expansion of the photomask 130 and enabling highly accurate transfer even after a long period of laser lift-off. Furthermore, the effects of particles on the photomask 130 can also be reduced.

[0107] The alignment camera 170 and the controller 180 are configured to monitor the irradiation area of ​​the laser 20 on the first substrate 1, and to control the laser oscillator 110, the photomask 130, and the stage 160 (upper stage 161 and lower stage 162). The controller 180 can, for example, move the photomask 130 to change the position of the pattern on the photomask 130 relative to the optical path of the laser 20b. The controller 180 can also move and / or rotate the upper stage 161 on the same plane to change the position of the first substrate 1, particularly the position of the transfer target 10, relative to the optical path of the laser 20. The controller 180 can also move and / or rotate the lower stage 162 on the same plane to change the position of the second substrate 2 relative to the optical path of the laser 20.

[0108] The controller 180 can also control the laser lift-off apparatus 100 to perform the laser lift-off method of the present invention as described below.

[0109] In the laser lift-off apparatus 100 shown in FIG. 1, the laser oscillator 110, the photomask 130, the alignment camera 170, the upper stage 161, and the lower stage 162 are each electrically connected to a controller 180 via a communication line 18.

[0110] The laser lift-off apparatus 100 of the present invention is not limited to an apparatus that performs Gap-LLO as shown in FIG. 1, but may also be an apparatus that performs Contact-LLO.

[0111] Figure 2 is a schematic diagram of a second example of a laser lift-off apparatus of the present invention. The laser lift-off apparatus 100 shown in Figure 2 is an apparatus configured to perform Contact-LLO. The laser lift-off apparatus 100 shown in Figure 2 is the same as the laser lift-off apparatus 100 shown in Figure 1, except that a stage 160 having an opening 160a supports a first substrate 1 and a second substrate 2 in a state in which a transfer target 10 on the first substrate 1 is in contact with the second substrate 2.

[0112] [Laser lift-off method] As an example of the laser lift-off method of the present invention, an example using the laser lift-off apparatus 100 shown in Fig. 1 will be described below. However, the laser lift-off method of the present invention is not limited to being performed using the laser lift-off apparatus 100 shown in Fig. 1, and can also be performed using the laser lift-off apparatus 100 shown in Fig. 2 or other apparatuses.

[0113] The laser lift-off method of the present invention includes a batch transfer process using partial irradiation, which will be described below with reference to FIG.

[0114] Fig. 3(a) is a schematic cross-sectional view showing the concept of laser irradiation in the batch transfer step in an example of the laser lift-off method of the present invention, and Fig. 3(b) is a diagram showing the positional relationship between the photomask pattern and one transfer object during the laser irradiation shown in Fig. 3(a).

[0115] In this example, a laser beam 20a emitted from a laser oscillator 110 shown in Fig. 1 is shaped into a laser beam 20b by a shaping optical system 120. This laser beam 20b is incident on a photomask 130 shown in Figs. 3(a) and (b).

[0116] 3(a) and 3(b) includes a laser-transparent substrate 131 and a pattern-forming layer 132 formed on the substrate 131. As shown in FIG. 3(b), a pattern 31 including a plurality of openings 132a is formed in the pattern-forming layer 132.

[0117] Since portions of the pattern formation layer 132 other than the openings 132a block the laser, only the component of the laser 20b incident on the photomask 130 that passes through the portion corresponding to the openings 132a is transmitted through the photomask 130. As a result, a laser having an irradiation shape with a pattern 31 (laser 20c shown in FIG. 1) is emitted from the photomask 130. Next, although not shown in FIG. 3, the laser 20c is incident on the reduction projection lens 150 shown in FIG. 1. In the reduction projection lens 150, the laser 20c is reduced while maintaining the irradiation shape of the pattern 31 shown in FIG. 3(b), and is emitted as the laser 20.

[0118] The laser 20 emitted from the reduction projection lens 150 is incident on the surface of the first substrate 1 opposite to the object 10 to be transferred. The laser 20 passes through the first substrate 1 and reaches the interface 11 between the first substrate 1 and the object 10 to be transferred.

[0119] Here, the term "interface" does not mean a strict boundary surface, but rather a region that is decomposed or the like by laser irradiation. Therefore, it can also be referred to as an ablation layer. Specifically, this includes a form in which at least a portion of the side of the first substrate 1 on which the transfer target 10 is provided is an ablation layer, a form in which an ablation layer is formed on the side of the first substrate 1 on which the transfer target 10 is provided, a form in which at least a portion of the transfer target 10 on the first substrate 1 side is an ablation layer, a form in which an ablation layer is formed on the first substrate 1 side of the transfer target 10, and a form in which an ablation layer is located between the first substrate 1 and the transfer target 10. In addition, even if a portion of the first substrate 1 or the transfer target 10 is an ablation layer, an ablation layer may be provided separately from the first substrate 1 or the transfer target 10.

[0120] 3 shows only one transfer object 10, in the collective transfer step in the laser lift-off method of the present invention, the interfaces 11 between a plurality of transfer objects 10 and the first substrate 1 are irradiated with the laser 20 all at once using a pattern 31 as shown in FIGS. 4(a) and 4(b). However, the plurality of transfer objects 10 do not necessarily have to be adjacent to each other as shown in the figure, and may be, for example, a plurality of transfer objects 10 that are not adjacent to each other but are arranged apart from each other.

[0121] As described above, the laser 20 has an irradiation shape that has the pattern 31 of the photomask 130. Therefore, as shown in Figures 3(a) and 3(b), the laser 20 is irradiated only to a portion 11a of the interface 11 between each of the multiple transfer objects 10 and the first substrate 1, rather than to the entire interface 11. In other words, in the laser lift-off method of the present invention, in the batch transfer step, the laser 20 is irradiated only to a portion 11a of the interface 11 between each of the multiple transfer objects 10 and the first substrate 1 (partial irradiation).

[0122] In the batch transfer step, the plurality of transfer objects 10 are partially irradiated with the laser 20 in this manner, whereby the plurality of transfer objects 10 are peeled off from the first substrate 1.

[0123] The energy required for delamination is the energy that can weaken the bonding force (e.g., adhesive force or joining force) between the transfer target 10 and the first substrate 1, and separate the transfer target 10 from the first substrate 1. For example, if there is a GaN layer at the interface between the transfer target 10 and the first substrate 1, the GaN layer must be decomposed (ablated) in order to delaminate the transfer target 10. The laser energy density required for this is high. Furthermore, nitrogen gas is generated by the decomposition of the GaN layer. The pressure of the generated nitrogen gas acts as a driving force, and the transfer target 10, which has been decomposed from the first substrate 1, moves to the second substrate 2. This completes the transfer process.

[0124] GaN is not easily decomposed, but decomposes rapidly when the energy threshold is exceeded. Therefore, in the bulk transfer process, as shown in FIG. 22, if a laser 20R is irradiated onto the entire surface of the interface 11 of each of multiple transfer objects 10 with the first substrate 1 at an energy sufficient to separate the transfer objects 10 from the first substrate 1, a large amount of nitrogen gas is rapidly generated, and the ejection vector of the generated gas becomes too large. As a result, the transfer objects 10 peeled off from the first substrate 1 are subjected to excessive pressure or have an excessively large initial velocity, causing them to collide with the surface of the second substrate 2 with a very large ejection force. As a result, the transfer objects 10 are prone to cracking while moving from the first substrate 1 to the second substrate 2, or to cracking or chipping when they reach the second substrate 2. Furthermore, the excessively large ejection vector makes it difficult to control the movement of the transfer objects 10 to the second substrate 2, making it more likely that unintended positional misalignment will occur when transferring the transfer objects 10 to the second substrate 2.

[0125] In contrast, in the laser lift-off method of the present invention, as explained above, by partially irradiating the laser 20 onto only a portion of the interface 11 of multiple transfer objects 10 in the batch transfer process, the amount of gas generated when multiple transfer objects 10 are peeled from the first substrate 1 is reduced, and the pressure experienced by the transfer objects 10 peeled from the first substrate 1 can be reduced. As a result, the propulsive force applied to the transfer objects 10 peeled from the first substrate 1 is appropriately suppressed, and the impact caused by contact between the transfer objects 10 and the second substrate 2 can be reduced. Furthermore, the peeled transfer objects 10 can be moved straight from the first substrate 1 to the second substrate 2, achieving a lift-off process with high transfer position accuracy.

[0126] The above describes an example in which a GaN layer decomposes during delamination. However, because delamination by laser lift-off is based on ablation, the problem of the ejection vector becoming too large inevitably occurs when full-surface irradiation is used, as described above. On the other hand, in the laser lift-off method of the present invention, partial irradiation is performed during the batch transfer process, thereby minimizing the ejection vector. Therefore, regardless of the combination of the first substrate 1 and the transfer object 10, the transfer object 10 can be transferred while preventing damage such as cracking or chipping of the transfer object 10. Furthermore, while the application of partial irradiation to laser lift-off using ablation has been described here, even in transfer methods that do not use ablation but impart a propulsive force to the transfer object by laser irradiation, partial laser irradiation can alleviate the propulsive force, leading to improved transfer accuracy.

[0127] Furthermore, even when transferring using the Contact-LLO method using the laser lift-off apparatus 100 shown in Fig. 2, in the case of full-surface irradiation, cracks and chips may occur due to the ejection vector becoming too large, as described above. According to the laser lift-off method of the present invention, even with the Contact-LLO method, the transfer target 10 can be transferred while preventing damage such as cracks and chips to the transfer target 10.

[0128] Furthermore, in the case where decomposition products are generated by laser irradiation, the amount of the products generated can be reduced, and the subsequent cleaning process can be simplified.

[0129] The laser lift-off method and laser lift-off apparatus of the present invention can be modified in various ways, and several modifications will be described below.

[0130] [Irradiated and non-irradiated areas] In the laser lift-off method of the present invention, the laser 20 is partially irradiated onto only a portion of the interface 11 between each of the multiple transfer objects 10 and the first substrate 1, thereby forming an irradiated area where the laser 20 is irradiated and a non-irradiated area where the laser 20 is not irradiated.

[0131] For example, the portion corresponding to the opening 132a of the pattern 31 of the photomask 130 shown in Figures 4(a) and (b) becomes the irradiated area, and the portion corresponding to the non-opening 132b other than the opening 132a of the pattern 31 becomes the non-irradiated area.

[0132] The form of partial irradiation is not particularly limited, but for example, as shown in FIGS. 4(a) and 4(b), the laser 20 may be irradiated so as to form a plurality of irradiation regions.

[0133] The shape of the irradiation area can be changed as appropriate, for example, by the pattern 31 of the photomask 130.

[0134] 5(a) to 5(d) show schematic examples of photomask patterns that can be used to form a plurality of irradiation regions in the present invention.

[0135] For example, as shown in Figures 5(a) and (b), the openings 132a of the photomask 130 may be circular. In Figure 5(a), the circular openings 132a are arranged in a staggered pattern, i.e., alternately. In Figure 5(b), the circular openings 132a are arranged in a matrix, i.e., in rows and columns. The shape of the openings 132a arranged in a staggered or matrix pattern is not limited to a circular shape, and may be an ellipse, a polygon, or another shape, or a combination thereof.

[0136] 5(c) and (d) show examples in which the openings 132a of the photomask 130 are rectangular. In FIG. 5(c), the longitudinal direction of the multiple rectangular openings 132a and the short side direction of the transfer object 10 are approximately aligned. In FIG. 5(d), the longitudinal direction of the multiple rectangular openings 132a and the long side direction of the transfer object 10 are approximately aligned. Here, "approximately aligned" means that two straight lines are aligned or that the angle between them is 5° or less.

[0137] 5(c), a plurality of rectangular openings 132a are arranged so as to straddle adjacent transfer objects 10. By using such a photomask 130, it is possible to irradiate the laser 20 so that the irradiation area straddles adjacent transfer objects.

[0138] 4 and 5, the non-openings 132b other than the openings 132a are continuous. Therefore, by irradiating with a laser using such a photomask 130, one continuous non-irradiated region can be formed.

[0139] On the other hand, for example, by using the photomask 130 of the examples shown in Figures 6(a) to (d), which is an inverted version of the pattern of the photomask 130 of each example in Figure 5, the laser 20 can be irradiated so as to form multiple non-irradiated areas.

[0140] For example, as shown in Figures 6(a) and (b), the non-opening portions 132b of the photomask 130 may be circular. In Figure 6(a), the circular non-opening portions 132b are arranged in a staggered pattern, i.e., alternately. In Figure 6(b), the circular non-opening portions 132b are arranged in a matrix, i.e., in rows and columns. The shape of the non-opening portions 132b arranged in a staggered or matrix pattern is not limited to a circular shape, and may be an elliptical shape, a polygonal shape, or another shape, or a combination thereof.

[0141] 6(c) and (d) show examples in which the non-opening portions 132b of the photomask 130 are rectangular. In FIG. 6(c), the longitudinal direction of the multiple rectangular non-opening portions 132b and the short-side direction of the transfer target 10 approximately coincide. In FIG. 6(d), the longitudinal direction of the multiple rectangular non-opening portions 132b and the long-side direction of the transfer target 10 approximately coincide. Here, approximately coincide means that two straight lines coincide or the angle between them is 5° or less.

[0142] 6(c), a plurality of rectangular non-openings 132b are arranged so as to straddle adjacent transfer objects 10. By using such a photomask 130, it is possible to irradiate the laser 20 so that the non-irradiated regions straddle adjacent transfer objects.

[0143] The means for forming a plurality of irradiation regions and the means for forming a plurality of non-irradiation regions are not limited to the above examples.

[0144] In the collective transfer step, the laser irradiation is preferably performed so that the laser irradiation area is 40 to 90% of the area of ​​the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1.

[0145] If the area of ​​the laser irradiation region in the collective transfer step is within the above range, it is possible to prevent damage to the transfer target objects 10 while maintaining transfer efficiency.

[0146] [Multi-stage irradiation] In the laser lift-off method of the present invention, it is preferable to further include a preliminary irradiation step, prior to the batch transfer step described above, in which a laser is irradiated onto the interface 11 between each of the multiple transfer objects 10 and the first substrate 1 with an energy that is smaller than the energy irradiated in the batch transfer step and that does not cause the transfer objects 10 to peel off from the first substrate 1.

[0147] By performing such a preliminary irradiation step, it is possible to further reduce the impact on the transfer target 10 in the bulk transfer step. Furthermore, in the bulk transfer step, when a material having a crystalline structure such as a GaN layer is used as the ablation layer, it is possible to suppress the occurrence of cleavage and thus the occurrence of residues.

[0148] In the preliminary irradiation step, the entire interface 11 between each of the plurality of transfer objects 10 and the first substrate 1 may be irradiated with the laser, but it is particularly preferable to irradiate only a portion of the interface 11 with the laser.

[0149] By performing partial irradiation in the preliminary irradiation step as well, when a material having a crystalline structure such as a GaN layer is used as the ablation layer, the occurrence of cleavage can be further suppressed, and therefore the occurrence of residues can be suppressed.

[0150] In the preliminary irradiation step, there is no particular limitation on the means for irradiating the laser 20 with energy that is smaller than the energy irradiated in the collective transfer step and that does not cause the transfer target 10 to peel off from the first substrate 1. Hereinafter, several examples will be described.

[0151] <First example> Fig. 7(a) shows a schematic diagram of a first example of the preliminary irradiation step in the laser lift-off method of the present invention, and Fig. 7(b) shows an example of the collective transfer step performed after the preliminary irradiation step shown in Fig. 7(a).

[0152] In the preliminary irradiation process shown in Figure 7(a), a portion 11b of the interface 11 between each of the multiple transfer objects 10 and the first substrate 1 is irradiated with a laser 20e with energy that is smaller than the energy of the laser 20 irradiated in the batch transfer process shown in Figure 7(b) and that does not cause the transfer objects 10 to peel off from the first substrate 1.

[0153] 7, in this example, the portion 11b of the interface 11 that is irradiated with the laser 20e in the preliminary irradiation step is changed to the portion 11a that is irradiated with the laser 20 in the collective transfer step. Such partial irradiation is achieved, for example, by using a photomask 130 having a second pattern 32 of openings 132c that is different from the pattern (first pattern) 31 of openings 132a, as shown in FIG. 7, and performing preliminary irradiation through this second pattern 32.

[0154] Fig. 8 shows a photograph of the first substrate 1 after the transfer objects 10 have been transferred in the preliminary irradiation step and the batch transfer step shown in Fig. 7. For comparison, Fig. 9 shows a photograph of the first substrate 1 after the transfer objects 10 have been transferred in the batch transfer step shown in Fig. 3.

[0155] 8 and 9, residues remaining on the first substrate 1 in Fig. 8 after the transfer object 10 was transferred in the preliminary irradiation step and the collective transfer step were not observed, as was the case with the first substrate 1 in Fig. 9, which was not subjected to the preliminary irradiation step. The reason for this will be explained below with reference to Figs. 10 and 11.

[0156] Fig. 10 is a schematic view showing the mechanism of the collective transfer step shown in Fig. 3. Fig. 11 is a schematic view showing the mechanism of the preliminary irradiation step and collective transfer step shown in Fig. 7.

[0157] 3, as described above, a component (e.g., GaN) contained in a portion 11a of the interface 11 between the transfer object 10 and the first substrate 1 is decomposed. For example, since the energy required to decompose GaN is high, the energy of the laser 20 incident on the portion 11a of the interface 11 is set to, for example, 1.4 J / cm. 2 When laser 20 having such energy is irradiated onto portion 11a of interface 11, this portion 11a becomes a normal peeled portion, but the energy is also transmitted to a portion of interface 11 adjacent to portion 11a. Furthermore, nitrogen gas produced by decomposition of GaN generates a large ejection vector 14, which acts on portion 11a of interface 11 and applies stress to the portion of interface 11 adjacent to portion 11a. As a result, a cleavage portion 11c is formed in the portion of interface 11 adjacent to portion 11a.

[0158] The resulting cleavage portion 11c remains as a residue 13 on the first substrate 1 and / or the transfer object 10 when the transfer object 10 is peeled off from the substrate 1. The black matter shown in FIG. 9 is the residue.

[0159] On the other hand, in the preliminary irradiation step shown in FIG. 11(a), a portion 11b of the interface 11 between the transfer target 10 and the first substrate 1 is irradiated with a laser 20e at an energy level that does not cause the transfer target 10 to peel off from the first substrate 1. With this type of laser irradiation, the GaN is partially separated in the portion 11b, but the peeling is very thin, and the first substrate 1 and the transfer target 10 remain loosely bonded. Furthermore, because the amount of GaN decomposition is small, the ejection vector 14 is smaller than the ejection vector shown in FIG. 10. This type of preliminary irradiation can prevent the cleavage portion 11c shown in FIG. 10 from occurring.

[0160] In the example shown in FIG. 11, the preliminary irradiation step shown in FIG. 11(a) is followed by the bulk transfer step shown in FIG. 11(b). In this bulk transfer step, a laser beam 20 with enough energy to decompose the GaN at the interface 11 and peel the transfer target 10 from the first substrate 1 is irradiated, as in the bulk transfer step shown in FIG. 10. At this time, the same large ejection vector 14 as shown in FIG. 10 is applied to a portion 11a of the interface 11. However, a very thin peel has already been generated in the portion 11b adjacent to the portion 11a of the interface 11 by the preliminary irradiation step, so that stress that would cause a cleavage portion 11c is prevented from being applied to the portion 11b. As a result, even after the transfer target 10 is peeled from the first substrate 1 as shown in FIG. 8, it is possible to prevent residues such as those shown in FIG. 9 from remaining.

[0161] In this embodiment, although the residue 13 originates from a part of the transfer target 10, it is part of the components that allow the transfer target 10 to be held on the first substrate 1, and therefore does not significantly affect the function of the transfer target 10. Therefore, even if the residue 13 remains on the first substrate 1 or the transfer target 10, it does not mean that the transfer target 10 is damaged.

[0162] However, if residue 13 remains after transfer, if the object to be transferred is a light-emitting element, it may cause uneven light emission or become a source of dust, making it necessary to clean the first substrate 1 and the object to be transferred 10, so suppressing the generation of residue is advantageous for mass production.

[0163] Here, the cleavage that may occur when a material having a crystalline structure such as a GaN layer is used as the ablation layer has been described.

[0164] On the other hand, the present invention is also effective for ablation layers in which the occurrence of cleavage is not a problem. Specifically, when an organic film such as a polyimide film is used as the ablation layer, cleavage does not occur, but by performing partial laser irradiation, it is possible to alleviate the excessive propulsive force generated in the transfer object 10 during laser irradiation, and it becomes possible to control the transfer of the transfer object 10 to the second substrate 2. Examples of such organic films include, in addition to polyimide films, organic films such as polymethyl methacrylate, polycarbonate, polyethylene terephthalate, nitrocellulose, polystyrene, poly(α-methylstyrene), and polytetrafluoroethylene.

[0165] When an organic film such as a polyimide film is used as the ablation layer, the laser energy density required for ablation of the ablation layer tends to be lower than the energy density when an inorganic film such as a GaN layer is used as the ablation layer. Specifically, the energy density required for ablation of a GaN layer is 1200 to 1600 mJ / cm. 2 On the other hand, the energy density required for ablation of polyimide films is 50-300mJ / cm 2 Therefore, when the shape of the laser beam irradiated onto the photomask 6 is rectangular or linear, the length in the longitudinal direction of the laser beam can be increased without changing the length in the lateral direction of the laser beam. Specifically, when the energy density is 1200 to 1600 mJ / cm 2 When trying to obtain a rectangular or line-shaped laser beam of about 1000 mJ / cm, the longitudinal length is limited to about 30 mm, but the energy density is limited to 50 to 300 mJ / cm. 2For a rectangular or line-shaped laser of about 100 mm, its longitudinal length can be extended to about 90 mm. Therefore, using such a long laser makes it possible to perform laser lift-off on a large number of objects 10 at once. Even if the rate of defective transfer appears to be low at first glance, when transferring such a large number of objects 10 at once, a large number of defective transfers will occur due to the large number of objects 10 to be transferred. In other words, when transferring a large number of objects 10 at once, it is very important to improve the transfer accuracy, and the industrial effects obtained by applying the present invention are very significant.

[0166] In the examples shown in Figures 7 and 11, the energy of the laser 20e irradiated onto the portion 11b of the interface 11 in the preliminary irradiation process is made smaller than the energy of the laser 20 irradiated onto the portion 11a of the interface 11 in the bulk transfer process by changing the energy of the laser 20d incident on the photomask 130, i.e., the output of the laser oscillator 110 shown in Figure 1.

[0167] <Second example> Fig. 12(a) shows a schematic diagram of a second example of the preliminary irradiation step in the laser lift-off method of the present invention. Fig. 12(b) shows an example of a batch transfer step performed after the preliminary irradiation step shown in Fig. 12(a). Fig. 13 shows an enlarged view of part XIII of the photomask used in Fig. 12.

[0168] The second example differs from the first example in that the energy of the laser 20b incident on the photomask 130 is not changed in the preliminary irradiation process and the batch transfer process, i.e., the laser output of the laser oscillator 110 is not changed, and in that the second pattern 32 of the photomask 130 is used in the preliminary irradiation process.

[0169] As shown in FIGS. 12(a) and 13, the second pattern 32 of the photomask 130 in the second example has a plurality of openings 132c, and dot-shaped non-openings 132d are provided in each opening 132c.

[0170] Each of the dot-shaped non-openings 132d has a wavelength smaller than the irradiation wavelength of the laser 20b irradiated onto the photomask 130. Therefore, the non-openings 132d do not contribute to a change in the irradiation shape of the laser 20b. Meanwhile, when the laser 20b strikes the non-openings 132d, the energy of the laser 20b is attenuated. Therefore, as the laser 20b passes through the second pattern 32 having the non-openings 132d of the photomask 130, it is shaped into a pattern corresponding to the openings 132c, the same as when the non-openings 132d are not present, while its energy is attenuated and it is emitted from the photomask 130 as a laser 20f. As a result, in the preliminary irradiation step of FIG. 12(a), the laser 20f can be irradiated onto the portions 11b of the interfaces 11b of each of the multiple transfer objects 10 with the first substrate 1 with an energy smaller than that of the laser 20 irradiated in the collective transfer step shown in FIG. 12(b), which is sufficient to prevent the transfer objects 10 from peeling off from the first substrate 1.

[0171] <Third example> Fig. 14(a) shows a schematic diagram of a third example of the preliminary irradiation step in the laser lift-off method of the present invention. Fig. 14(b) shows an example of a batch transfer step performed after the preliminary irradiation step shown in Fig. 14(a). Fig. 15 shows an enlarged view of part XV of the photomask used in Fig. 14.

[0172] The third example differs from the second example in that stripe-shaped non-opening portions 132f are provided within each opening portion 132e in the second pattern 32 of the photomask 130.

[0173] The width of each of the stripe-shaped non-openings 132f is smaller than the wavelength of the laser 20b irradiated onto the photomask 130. Therefore, the non-openings 132f do not contribute to changes in the irradiation shape of the laser 20b. Meanwhile, when the laser 20b strikes the non-openings 132f, the energy of the laser 20b is attenuated. Therefore, as the laser 20b passes through the second pattern 32 having the non-openings 132f of the photomask 130, it is shaped into a pattern corresponding to the openings 132e, the same as when the non-openings 132f are not present, and the energy is attenuated before it is emitted from the photomask 130 as the laser 20g. As a result, in the preliminary irradiation step of FIG. 14(a), the laser 20g can be irradiated onto the portions 11b of the interfaces 11b of each of the multiple transfer objects 10 with the first substrate 1 with an energy smaller than that of the laser 20 irradiated in the collective transfer step shown in FIG. 14(b), which is sufficient to prevent the transfer objects 10 from peeling off from the first substrate 1.

[0174] <Fourth example> Fig. 16(a) shows a schematic diagram of a fourth example of the preliminary irradiation step in the laser lift-off method of the present invention. Fig. 16(b) shows an example of a batch transfer step performed after the preliminary irradiation step shown in Fig. 16(a). Fig. 17 shows an enlarged view of part XVII of the photomask used in Fig. 16.

[0175] The fourth example differs from the second example in that second pattern 32 of photomask 130 includes a plurality of phase shift mask portions 132g.

[0176] A portion of the laser beam 20b incident on the phase shift mask portion 132g passes through the phase shift film included in the phase shift mask portion 132g, resulting in a 180° phase shift. Because the phase-shifted component is 180° out of phase with the component that did not pass through the phase shift film, they cancel each other out. As a result, the energy of the laser beam 20b incident on the phase shift mask portion 132g is attenuated. As the laser beam 20b passes through the second pattern 32 having the phase shift mask portion 132g of the photomask 130, its energy is attenuated while it is shaped into a pattern corresponding to the phase shift mask portion 132g, and it is then emitted from the photomask 130 as the laser beam 20h. As a result, in the preliminary irradiation process of Figure 16(a), a portion 11b of the interface 11 between each of the multiple transfer objects 10 and the first substrate 1 can be irradiated with laser 20h at an energy that is smaller than the energy of laser 20 irradiated in the batch transfer process shown in Figure 16(b), and that does not cause the transfer objects 10 to peel off from the first substrate 1.

[0177] In this way, according to the second to fourth examples, for example, in the preliminary irradiation step, without changing the laser output from the laser oscillator 110, it is possible to irradiate the part 11b of the interface 11 with the first substrate 1 of each of the plurality of transfer objects 10 with a laser with energy that is smaller than the energy of the laser 20 irradiated in the subsequent collective transfer step and that does not cause the transfer objects 10 to peel off from the first substrate 1. Being able to perform the preliminary irradiation step and the collective transfer step without changing the output of the laser oscillator 110 is very advantageous in terms of mass production.

[0178] A specific example in which the preliminary irradiation step and the collective transfer step of the second example described with reference to FIGS. 12 and 13 can be performed will be described with reference to FIGS.

[0179] 18 is a schematic diagram showing an example of the arrangement of a photomask 130 and a plurality of transfer objects 10 that can perform the preliminary irradiation step and the collective transfer step of the second example. In FIG. 18, illustrations other than the photomask 130 and the plurality of transfer objects 10 are omitted.

[0180] The photomask 130 shown in FIG. 18 includes a second portion 134 having the second pattern 32 shown in FIG. 12(a) and a first portion 133 having the first pattern 31 shown in FIG. 12(b).

[0181] 18 indicates the movement direction of the multiple transfer objects 10. In this example, the photomask 130 and the transfer objects 10 are arranged so that the second pattern 32 of the photomask 130 is positioned on the multiple transfer objects 10 before the first pattern 31.

[0182] In the second pattern 32, a chromium shielding film, which is a pattern formation layer 132 having openings 132c and dot-shaped non-openings 132d as shown in Figures 12(a) and 13, is formed on a quartz glass substrate 131.

[0183] The dot-shaped non-opening portions 132d cover 15% of the opening area of ​​each opening portion 132c.

[0184] On the other hand, in the first pattern 31, a chromium shielding film as a pattern formation layer 132 in which an opening 132a shown in FIG. 12(b) is formed is formed on a quartz glass as a base material 131.

[0185] Thus, a first portion 133 of the photomask 130 has a first laser transmittance and a second portion 134 has a second laser transmittance that is lower than the first laser transmittance.

[0186] Specifically, when laser lift-off is performed with such an arrangement, the energy (energy density) of the laser 20f irradiated onto the part 11b of the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1 in the preliminary irradiation step shown in Fig. 12(a) is 15% lower than the energy of the laser 20 irradiated onto the part 11a of the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1 in the collective transfer step shown in Fig. 12(b). For example, if the energy irradiated onto the part 11a of the interface 11 in the collective transfer step is 1.4 J / cm 2In this case, the energy of the laser 20f irradiated onto the part 11b of the interface 11 in the preliminary irradiation step is 1.2 J / cm 2 This becomes:

[0187] When the preliminary irradiation process and the batch transfer process are performed in the arrangement shown in Figure 18, the second pattern 32 of the multiple irradiation areas 32a in the preliminary irradiation process and the first pattern 31 of the multiple irradiation areas 31a in the batch transfer process are formed misaligned, as shown in Figure 19, for example.

[0188] FIG. 18 shows, as an example, a photomask 130 having the second pattern 32 shown in FIGS. 12 and 13, but the photomask 130 used in the present invention may have the second pattern 32 of the other examples described above, or another second pattern.

[0189] The above-described preliminary irradiation step can be carried out in various ways.

[0190] For example, the preliminary irradiation step can be carried out 1 to 4 times.

[0191] Although the number of times of the preliminary irradiation step is not particularly limited, the speed of the transfer operation by laser lift-off can be improved by performing the preliminary irradiation step once or twice. Also, by performing the preliminary irradiation step three or four times, it becomes easier to control the impact on the object to be transferred during laser lift-off while maintaining a moderate speed of the transfer operation by laser lift-off.

[0192] For example, in each of the preliminary irradiation process and the batch transfer process, it is preferable to perform laser irradiation so that the laser irradiation area (for example, irradiation areas 31a and 32a shown in Figure 19) is 10 to 60% of the area of ​​the interface 11 with the first substrate 1 of each of the multiple transfer objects 10.

[0193] If the irradiation area in the partial irradiation in each of the preliminary irradiation process and the batch transfer process is within the range of 10 to 60% of the area of ​​the interface 11 with the first substrate 1 of each of the multiple transfer objects 10, the transfer objects can be efficiently transferred from the first substrate to the second substrate, and a tolerance can be provided for laser irradiation errors.

[0194] It is also preferable to change the laser irradiation area between the preliminary irradiation step and the collective transfer step.

[0195] By changing the laser irradiation area between the preliminary irradiation process and the batch transfer process, it is possible to suppress the occurrence of cleavage 13 as shown in FIG. 10 when a material having a crystalline structure such as a GaN layer is used as the ablation layer, as described with reference to FIG. 11, for example.

[0196] In addition, it is preferable to carry out the preliminary irradiation process and the batch transfer process so that there is no overlapping of the laser irradiation areas, or so that the overlapping of the laser irradiation areas is 10% or less of the area of ​​the interface 11 between each of the multiple transfer objects 10 and the first substrate 1.

[0197] The irradiation areas in the preliminary irradiation step and the collective transfer step may overlap, and by making the overlapping portion greater than 0% and equal to or less than 10%, it is possible to provide a margin for laser irradiation error.

[0198] For example, by arranging the openings in the first portion 133 and the second portion 134 of the photomask 130 in a matrix, the degree of overlap of the irradiated regions can be easily controlled.

[0199] Furthermore, when the irradiated or non-irradiated regions are linear as shown in Figures 4, 5(c) and (d), and 6(c) and (d), it is preferable to arrange the irradiated or non-irradiated regions at intervals equal to or greater than the width in the short direction of the irradiated or non-irradiated regions, which makes it easy to control the degree of overlap of the irradiated regions.

[0200] Furthermore, in total during the preliminary irradiation step and the collective transfer step, the laser can be irradiated onto 40 to 100% of the area of ​​the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1.

[0201] Transfer can be performed more efficiently by irradiating the laser onto 40% or more of the area of ​​the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1 in the preliminary irradiation step and the collective transfer step combined. Also, the laser may be irradiated onto the entire area of ​​the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1, i.e., 100%, in the preliminary irradiation step and the collective transfer step combined.

[0202] It is particularly preferable that the laser lift-off apparatus of the present invention is configured so as to be capable of carrying out the above-described preliminary irradiation step.

[0203] For example, the laser lift-off apparatus 100 of the present invention can be further configured so that the energy with which the laser is irradiated onto the interface 11 between the multiple transfer objects 10 and the first substrate 1 can be switched between energy that does not cause the transfer objects 10 to peel off from the first substrate 1 and energy that peels the transfer objects 10 from the first substrate 1, as in the first example described with reference to Figure 7.

[0204] 12 to 17, the laser lift-off apparatus 100 of the present invention can be further configured such that the pattern of the photomask 130 includes a first pattern 31 and a second pattern 32, and that the laser 20 can be irradiated simultaneously through the first pattern 31 to the interfaces 11 between the plurality of transfer targets 10 and the first substrate 1 with energy that separates the transfer targets 10 from the first substrate 1, and that the laser can be irradiated simultaneously through the second pattern 32 to the interfaces 11 between the plurality of transfer targets 10 and the first substrate 1 with energy that does not separate the transfer targets 10 from the first substrate 1. The laser lift-off apparatus 100 of this aspect is advantageous in terms of mass production.

[0205] [Items to be transferred] The object to be transferred in the present invention is not particularly limited. For example, the object to be transferred may be selected from the group consisting of a semiconductor chip, an LED chip, a resin material film, and an inorganic film. The resin material film may contain an inorganic material. The resin material film may have a multilayer structure, and the multiple films constituting the multilayer structure may consist solely of resin material films or may be a combination of resin material films and inorganic material films.

[0206] When a thin object to be transferred, with a thickness of 1 to 10 μm, is irradiated on its entire surface using a conventional laser lift-off method, the object becomes more susceptible to damage during laser lift-off if its longitudinal dimension or area increases. Specifically, when a thin object to be transferred, with a longitudinal dimension of 80 μm or more, or an area of ​​6400 μm, is irradiated on its entire surface using a conventional laser lift-off method, the object becomes more susceptible to damage during laser lift-off. 2 In the case of the above-mentioned transfer objects, the transfer objects are prone to cracking during laser lift-off due to full-surface irradiation, so the application of the present invention, which can alleviate the propulsion force applied to the transfer objects, is effective. There are no particular restrictions on the upper limits of the longitudinal dimension and the area, but from the viewpoint of ease of production, it is recommended that they be 500 μm or less and 40,000 μm or less, respectively. 2 It is about the following.

[0207] [Method for manufacturing receptor substrate] The laser lift-off method of the present invention described above can be applied to, for example, a method for manufacturing a receptor substrate.

[0208] For example, a method for manufacturing a receptor substrate on which a plurality of transfer objects are arranged includes the steps of preparing a donor substrate having the plurality of transfer objects and a receptor precursor substrate, and transferring the transfer objects from the donor substrate to the receptor precursor substrate by laser lift-off to obtain a receptor substrate, wherein in the step of obtaining the receptor substrate, laser lift-off is performed from the donor substrate as the first substrate to the receptor precursor substrate as the second substrate by the laser lift-off method of the present invention.In this case, since the transfer objects are transferred to obtain the receptor substrate by the laser lift-off method of the present invention, there is no misalignment of the transfer objects, and a receptor substrate with undamaged transfer objects can be manufactured.

[0209] The method for manufacturing a receptor substrate of the present invention is one example of the application of the laser lift-off method of the present invention, and the application of the laser lift-off method of the present invention is not limited thereto.

[0210] [Photomask] The photomask of the present invention is a photomask that can be used in the laser lift-off method of the present invention described above, and therefore encompasses all of the aspects of the photomask 130 described above.

[0211] For example, the photomask of the first embodiment of the present invention is a photomask 130 used in a laser lift-off method for transferring the transfer objects 10 from a first substrate 1 having the transfer objects 10 to a second substrate 2 by laser lift-off, and is configured to irradiate the received laser simultaneously onto the interface 11 between each of the multiple transfer objects 10 and the first substrate 1, and has a pattern 31 that shapes the laser so that only a portion 11a of the interface 11 between each of the multiple transfer objects 10 and the first substrate 1 becomes the irradiated area.

[0212] As explained above, the pattern 31 of the photomask 130 may be such that the laser is shaped to form multiple irradiation areas, or may be such that the laser is shaped to form multiple non-irradiation areas where the laser is not irradiated on the interface 11 between each of the multiple transfer objects 10 and the first substrate 1.

[0213] Furthermore, for example, by using a photomask 130 having a pattern (first pattern) 31 formed thereon and a first portion 133 having a first laser transmittance and a second portion 134 having a second laser transmittance lower than the first laser transmittance, the preliminary irradiation process and the collective transfer process described above can be carried out without changing the output of the laser oscillator 110.

[0214] Expressing such a photomask 130 from another perspective, the photomask of the second embodiment of the present invention can be said to be a photomask used in a laser lift-off method for transferring an object 10 from a first substrate 1 having the object 10 to a second substrate 2 by laser lift-off, and can be described as a photomask 130 having a first portion 133 having a first laser transmittance and a second portion 134 having a second laser transmittance lower than the first laser transmittance, on which a pattern 31 for shaping the received laser into a pattern is formed.

[0215] By performing the laser lift-off method of the present invention using the photomask 130 of the present invention, it is possible to prevent the object from being displaced during transfer and to prevent damage to the object. Note that the laser lift-off method of the present invention can also be performed without using the photomask 130 of the present invention. [Example]

[0216] EXAMPLES The present invention will be specifically explained below using examples and comparative examples, but the present invention is not limited to these.

[0217] Example 1 A sapphire substrate with 1.5 million LED chips, each measuring 40 μm x 60 μm, was prepared as the first substrate.

[0218] A quartz substrate having a silicone rubber layer as an adhesive layer on its surface was prepared as a second substrate.

[0219] In Example 1, a total of 1.5 million LED chips were transferred from a first substrate to a second substrate by the Contact-LLO method using the laser lift-off apparatus shown in FIG.

[0220] In Example 1, the preliminary irradiation step and the collective transfer step were carried out using the photomask 130 described with reference to FIGS. Specifically, in this embodiment, as shown in FIG. 18, multiple transfer objects are moved relative to the photomask in the direction of the arrow, so that the laser lift-off is actually performed in the following order: (i) a pre-irradiation step for the lower row (ii) a batch transfer step for the lower row and a preliminary irradiation step for the upper row (iii) a batch transfer step for the upper row and a preliminary irradiation step for the row one row above the upper row; (iv) a batch transfer step for the row one row above the upper row and a preliminary irradiation step for the row two rows above the upper row Of course, the preliminary irradiation step and the collective transfer step may be completed for each certain region, for example, for each row, and then the preliminary irradiation step and the collective transfer step may be performed for another region. Furthermore, a batch transfer process may be performed on all the LED chips after a preliminary irradiation process has been performed on all the LED chips. Here, the preliminary irradiation process for all the LED chips may be a single batch transfer process, or may be multiple batch transfer processes divided into certain areas. Furthermore, the batch transfer process for all the LED chips may be a single batch transfer process, or may be multiple batch transfer processes divided into certain areas.

[0221] The first pattern 31 and the second pattern 32 of the photomask 130 were each a 1:1 line and space pattern of 8 μm.

[0222] In the preliminary irradiation step, the energy (energy density) of the laser 20f irradiated onto the part 11b of the interface 11 between the first substrate 1 and each of the transfer objects 10 is set to 1.2 J / cm 2 It was decided.

[0223] Thereafter, the photomask 130 was moved by 8 μm in the direction of the arrow shown in FIG. 18, and a collective transfer step was carried out.

[0224] In the batch transfer process, the energy (energy density) of the laser 20 irradiated onto the part 11a of the interface 11 between each of the plurality of transfer objects 10 and the first substrate 1 is set to 1.4 J / cm 2 It was decided.

[0225] Example 2 In Example 2, a total of 1.5 million LED chips were transferred from the first substrate to the second substrate in the same manner as in Example 1, except that the preliminary irradiation step was not performed.

[0226] (Comparative Example) In the comparative example, a total of 1.5 million LED chips were transferred from the first substrate to the second substrate in the same manner as in Example 2, except that in the batch transfer process, the laser was irradiated to all of the interfaces 11 between each of the multiple transfer objects 10 and the first substrate 1.

[0227] When the LED chips transferred to the second substrate in Examples 1 and 2 were checked, it was found that the positional accuracy of the LED chips was high and no major damage to the LED chips was observed.

[0228] On the other hand, damage to 10% of the LED chips transferred to the second substrate in the comparative example was confirmed.

[0229] 20 shows a photograph of the first substrate after transfer in Example 1. As is clear from FIG. 20, almost no residue was observed on the first substrate after transfer in Example 1.

[0230] On the other hand, Fig. 9 is a photograph of the first substrate after transfer in Example 2. As is clear from Fig. 9, some residues were observed on the first substrate after transfer in Example 2.

[0231] In this evaluation, the residue was observed as a black residue due to the light used in the microscope.

[0232] In the above-described embodiment, an example was described in which an LED chip having a GaN layer, which is the transfer target, was lifted off from a sapphire substrate serving as a first substrate. However, this is not limited to this embodiment. Specifically, the present invention can also be applied to cases in which a chip-shaped resin material film, inorganic film, or microdevice or chip provided on a first substrate based on a sapphire substrate or glass substrate is transferred to a second substrate. Furthermore, this also includes cases in which a transfer target bonded via an ablation layer, such as a polyimide film, is transferred from a first substrate having an ablation layer formed on its surface to a second substrate.

[0233] Furthermore, the present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and exhibits similar effects is included within the technical scope of the present invention. The inventions described in the claims of the original application at the time of filing are as follows: [1] A laser lift-off method for transferring an object from a first substrate having the object to a second substrate by laser lift-off, comprising: a batch transfer step of irradiating interfaces between the plurality of transfer objects and the first substrate with a laser at the same time, thereby peeling the plurality of transfer objects from the first substrate and transferring them at the same time to the second substrate; A laser lift-off method in which, in the collective transfer step, the laser is irradiated onto only a portion of the interface between each of the plurality of transfer objects and the first substrate. [2] The laser lift-off method according to [1], further comprising a preliminary irradiation step, prior to the batch transfer step, of irradiating the interface between each of the plurality of transfer objects and the first substrate with a laser at an energy level that is lower than that irradiated in the batch transfer step and that does not cause the transfer objects to peel off from the first substrate. [3] The laser lift-off method according to [2], wherein in the preliminary irradiation step, the laser is irradiated onto only a portion of the interface between each of the plurality of transfer objects and the first substrate. [4] The laser lift-off method according to [2] or [3], wherein the preliminary irradiation step is carried out 1 to 4 times. [5] A laser lift-off method according to any one of [2] to [4], wherein in each of the preliminary irradiation process and the collective transfer process, laser irradiation is performed so that the laser irradiation area is 10 to 60% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate. [6] The laser lift-off method according to any one of [2] to [5], wherein the laser irradiation area is changed between the preliminary irradiation step and the collective transfer step. [7] The laser lift-off method described in [6], wherein the preliminary irradiation process and the collective transfer process are performed so that there is no overlapping portion of the laser irradiation areas, or so that the overlapping portion of the laser irradiation areas is 10% or less of the area of ​​the interface between each of the multiple transfer objects and the first substrate. [8] A laser lift-off method according to [6] or [7], wherein the laser is irradiated to 40 to 100% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate in the preliminary irradiation process and the batch transfer process combined. [9] The laser lift-off method according to any one of [2] to [8], wherein the output of the laser is changed between the preliminary irradiation step and the collective transfer step.

[10] providing a photomask including a first portion having a first laser transmittance and a second portion having a second laser transmittance lower than the first laser transmittance; In the preliminary irradiation step, the laser is irradiated through the second portion of the photomask, The laser lift-off method according to any one of [2] to [8], wherein in the collective transfer step, the laser is irradiated through the first portion of the photomask.

[11] The laser lift-off method according to [1], wherein in the batch transfer process, laser irradiation is performed so that the laser irradiation area is 40 to 90% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate.

[12] A laser lift-off method according to any one of [1] to

[11] , wherein in the batch transfer process, the laser is irradiated to the interface between each of the plurality of transfer objects and the first substrate so that a plurality of irradiation areas are formed where the laser is irradiated.

[13] The laser lift-off method according to

[12] , wherein in the collective transfer step, the laser is irradiated so that the irradiation area has at least one shape selected from the group consisting of a circle, an ellipse, and a polygon.

[14] The laser lift-off method according to

[12] , wherein in the collective transfer step, the laser is irradiated so that the irradiation area has a line shape.

[15] The laser lift-off method described in

[12] , wherein in the batch transfer process, the irradiation area has a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the irradiation area and the longitudinal direction of the object to be transferred approximately coincide.

[16] The laser lift-off method described in

[12] , wherein in the batch transfer process, the irradiation area has a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the irradiation area and the short side direction of the object to be transferred approximately coincide with each other.

[17] A laser lift-off method according to

[12] , wherein in the batch transfer process, the irradiation area has a rectangular or linear shape, and the laser is irradiated so that the irradiation area straddles the adjacent objects to be transferred.

[18] A laser lift-off method according to any one of [1] to

[11] , wherein in the batch transfer process, the laser is irradiated to the interface between each of the plurality of transfer objects and the first substrate so as to form a plurality of non-irradiated areas where the laser is not irradiated.

[19] The laser lift-off method according to

[18] , wherein in the batch transfer process, the laser is irradiated so that the non-irradiated area has at least one shape selected from the group consisting of a circle, an ellipse, and a polygon.

[20] The laser lift-off method according to

[18] , wherein in the collective transfer step, the laser is irradiated so that the non-irradiated region has a line shape.

[21] The laser lift-off method described in

[18] , wherein in the batch transfer process, the non-irradiated area has a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the non-irradiated area and the longitudinal direction of the object to be transferred are approximately aligned.

[22] The laser lift-off method described in

[18] , wherein in the batch transfer process, the non-irradiated area has a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the non-irradiated area and the short side direction of the object to be transferred are approximately aligned.

[23] The laser lift-off method described in

[18] , wherein in the batch transfer process, the non-irradiated area has a rectangular or linear shape, and the laser is irradiated so that the non-irradiated area straddles the adjacent objects to be transferred.

[24] The laser lift-off method according to any one of [1] to

[23] , wherein the object to be transferred is selected from the group consisting of a semiconductor chip, an LED chip, a resin material film, and an inorganic film.

[25] A method for manufacturing a receptor substrate on which a plurality of transfer objects are arranged, comprising: preparing a donor substrate having the plurality of transfer objects and a receptor precursor substrate; transferring the object from the donor substrate to the receptor precursor substrate by laser lift-off to obtain a receptor substrate; Including, A method for manufacturing a receptor substrate, in which, in the step of obtaining the receptor substrate, laser lift-off is performed from the donor substrate as the first substrate to the receptor precursor substrate as the second substrate by the laser lift-off method described in any one of [1] to

[23] .

[26] A laser lift-off apparatus for transferring an object from a first substrate having the object to a second substrate by laser lift-off, comprising: a laser oscillator; a stage that supports the first substrate and the second substrate so that they face each other; a photomask disposed in an optical path between the laser oscillator and the stage; Equipped with the laser oscillator, the photomask, and the stage are configured to collectively irradiate interfaces between the plurality of transfer objects and the first substrate with a laser from the laser oscillator; a photomask having a pattern for shaping the laser from the laser oscillator into a shape that irradiates only a portion of the interface between each of the plurality of transfer objects and the first substrate;

[27] The laser lift-off apparatus described in

[26] , further configured to be able to switch the energy with which the laser irradiates the interface between the plurality of transfer objects and the first substrate between an energy that does not cause the transfer objects to peel off from the first substrate and an energy that peels off the transfer objects from the first substrate.

[28] The pattern of the photomask includes a first pattern and a second pattern; the laser is irradiated through the first pattern at the same time to the interfaces between the plurality of transfer objects and the first substrate with the energy sufficient to peel the transfer objects from the first substrate; and

[27] The laser lift-off apparatus according to

[27] , further configured to be able to irradiate the laser through the second pattern at the same time to the interfaces between the plurality of transfer objects and the first substrate with the energy that does not cause the transfer objects to peel off from the first substrate.

[29] A photomask used in a laser lift-off method for transferring an object from a first substrate having the object to a second substrate by laser lift-off, The laser beam is irradiated simultaneously onto the interface between each of the plurality of transfer objects and the first substrate, a photomask having a pattern for shaping the laser so that only a portion of the interface between each of the plurality of transfer objects and the first substrate is an irradiated area;

[30] The photomask according to

[29] , wherein the pattern shapes the laser so that a plurality of the irradiation regions are formed.

[31] A photomask as described in

[29] , wherein the pattern is shaped by the laser so that multiple non-irradiated areas are formed at the interface between each of the multiple transfer objects and the first substrate, where the laser is not irradiated.

[32] a first portion having the pattern formed thereon and a first laser transmittance; a second portion having a second laser transmissivity lower than the first laser transmissivity; The photomask according to any one of

[29] to

[31] , comprising:

[33] A photomask used in a laser lift-off method for transferring an object from a first substrate having the object to a second substrate by laser lift-off, a first portion having a pattern formed thereon for shaping an received laser beam into the pattern and having a first laser transmittance; a second portion having a second laser transmissivity lower than the first laser transmissivity; A photomask having

Claims

1. A transfer method for transferring an object from a first substrate having the object to a second substrate by using a laser, comprising: a batch transfer step of irradiating interfaces between the plurality of transfer objects and the first substrate with a laser at the same time, thereby peeling the plurality of transfer objects from the first substrate and transferring them at the same time to the second substrate; In the collective transfer step, the laser is irradiated onto only a part of the interface between each of the plurality of transfer objects and the first substrate, In the batch transfer step, Irradiating the laser to the interface between each of the plurality of transfer objects and the first substrate so that a plurality of irradiation regions where the laser is irradiated are formed; or In the collective transfer step, the laser is irradiated onto the interface between each of the plurality of transfer objects and the first substrate so that a plurality of non-irradiated regions where the laser is not irradiated are formed. Transfer method.

2. 2. The transfer method according to claim 1, further comprising a preliminary irradiation step, prior to the batch transfer step, of irradiating the interface between each of the plurality of transfer objects and the first substrate with a laser at an energy level that is lower than the energy irradiated in the batch transfer step and that does not cause the transfer objects to peel off from the first substrate.

3. The transfer method according to claim 2 , wherein in the preliminary irradiation step, the laser is irradiated onto only a part of the interface between each of the plurality of transfer objects and the first substrate.

4. The transfer method according to claim 2, wherein the preliminary irradiation step is carried out 1 to 4 times.

5. 3. The transfer method according to claim 2, wherein in each of the preliminary irradiation process and the collective transfer process, the laser irradiation area is 10 to 60% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate.

6. The transfer method according to claim 2 , wherein the laser irradiation area is changed between the preliminary irradiation step and the collective transfer step.

7. 7. The transfer method according to claim 6, wherein the preliminary irradiation process and the batch transfer process are performed so that there is no overlapping portion of the laser irradiation areas, or so that the overlapping portion of the laser irradiation areas is 10% or less of the area of ​​the interface between each of the plurality of transfer objects and the first substrate.

8. The transfer method according to claim 6, wherein the laser is irradiated onto 40 to 100% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate in the preliminary irradiation process and the collective transfer process combined.

9. The transfer method according to claim 2 , wherein the output of the laser is changed between the preliminary irradiation step and the collective transfer step.

10. providing a photomask including a first portion having a first laser transmissivity and a second portion having a second laser transmissivity lower than the first laser transmissivity; In the preliminary irradiation step, the laser is irradiated through the second portion of the photomask, The transfer method according to claim 2 , wherein the collective transfer step includes irradiating the laser through the first portion of the photomask.

11. 2. The transfer method according to claim 1, wherein in the batch transfer step, the laser is irradiated so that the laser irradiation area is 40 to 90% of the area of ​​the interface between each of the plurality of transfer objects and the first substrate.

12. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form a plurality of irradiation areas, and the laser is irradiated so that the irradiation areas have at least one shape selected from the group consisting of a circle, an ellipse, and a polygon.

13. The transfer method according to claim 1 , wherein in the collective transfer step, the laser is irradiated so as to form a plurality of the irradiation regions, and the irradiation regions have a linear shape.

14. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form a plurality of irradiation areas, the irradiation areas have a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the irradiation areas and the longitudinal direction of the object to be transferred approximately coincide with each other.

15. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form a plurality of irradiation areas, the irradiation areas have a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the irradiation area and the short direction of the object to be transferred approximately coincide with each other.

16. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form a plurality of irradiation areas, the irradiation areas have a rectangular or linear shape, and the laser is irradiated so that the irradiation areas straddle adjacent objects to be transferred.

17. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form a plurality of non-irradiated areas, and the non-irradiated areas have at least one shape selected from the group consisting of a circle, an ellipse, and a polygon.

18. The transfer method according to claim 1 , wherein in the collective transfer step, the laser is irradiated so as to form a plurality of the non-irradiation regions, and the non-irradiation regions have a linear shape.

19. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form multiple non-irradiated areas, the non-irradiated areas have a rectangular or linear shape, and the longitudinal direction of the non-irradiated areas is approximately aligned with the longitudinal direction of the object to be transferred.

20. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form multiple non-irradiated areas, the non-irradiated areas have a rectangular or linear shape, and the laser is irradiated so that the longitudinal direction of the non-irradiated areas and the short direction of the object to be transferred approximately coincide with each other.

21. 2. The transfer method according to claim 1, wherein in the batch transfer process, the laser is irradiated so as to form multiple non-irradiated areas, the non-irradiated areas have a rectangular or linear shape, and the laser is irradiated so that the non-irradiated areas straddle adjacent objects to be transferred.

22. 2. The transfer method according to claim 1, wherein the object to be transferred is selected from the group consisting of a semiconductor chip, an LED chip, a resin material film, and an inorganic film.

23. The transfer method according to claim 1 , wherein the transfer using a laser is a laser lift-off.

24. A method for manufacturing a receptor substrate on which a plurality of transfer objects are arranged, comprising: preparing a donor substrate having the plurality of transfer objects and a receptor precursor substrate; transferring the object from the donor substrate to the receptor precursor substrate by a laser to obtain a receptor substrate; Including, A method for manufacturing a receptor substrate, in which, in the process of obtaining the receptor substrate, the plurality of transfer objects are transferred from the donor substrate as the first substrate to the receptor precursor substrate as the second substrate by the transfer method described in any one of claims 1 to 23.

25. 2. The method for producing a receptor substrate according to claim 1, wherein the transfer using a laser is laser lift-off.

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