Method for transferring optical device layer

Abstract

Provided is a method for transferring an optical device layer. When transferring the optical device layer and performing laser lift-off, the reduction in the transfer rate of the optical device to the transfer member can be suppressed. The transfer method for transferring the optical device layer includes a transfer member bonding step, a buffer layer destruction step, an optical device layer transfer step, an adhesive removal step, and an optical device layer transfer step. In the transfer member bonding step, the optical device wafer and the transfer member are bonded by means of an adhesive, and the adhesive is filled in the gap between the optical device layer divided into chip sizes on the optical device wafer and the optical device layer. In the adhesive removal step, at least a part of the adhesive filled in the gap between the optical device layer and the optical device layer is removed so that the optical device layer embedded in the adhesive layer through the transfer member bonding step protrudes from the adhesive layer.

Description

Technical Field

[0001] The present invention relates to a method for transferring an optical device layer, and transfers the optical device layer from an optical device wafer. Background Art

[0002] Optical devices such as LEDs (Light Emitting Diodes) are formed, for example, by epitaxially growing an n-type semiconductor layer and a p-type semiconductor layer constituting a pn junction on the front surface of a sapphire substrate. There is known a peeling technique called laser peeling for peeling the thus-formed optical device layer from the sapphire substrate and transferring it to a transfer member (see Patent Documents 1 and 2). In recent years, manufacturing techniques for extremely small-sized LEDs called micro-LEDs have also been developed, and there is known a technique for fabricating a large number of LEDs by dividing a semiconductor layer by etching (see Patent Document 3).

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2004-072052

[0004] Patent Document 2: Japanese Patent Application Laid-Open No. 2016-021464

[0005] Patent Document 3: Japanese Patent Application Laid-Open No. 2018-107421

[0006] However, when laser peeling is performed on the above-described micro-LEDs, there is a problem that the transfer rate of the LEDs to the transfer member decreases. Summary of the Invention

[0007] Accordingly, an object of the present invention is to provide a method for transferring an optical device layer, which transfers the optical device layer from an optical device wafer and can suppress a decrease in the transfer rate of the optical device to the transfer member during laser peeling.

[0008] According to the present invention, there is provided a method for transferring an optical device layer, which transfers the optical device layer of an optical device wafer. The optical device wafer is obtained by laminating a plurality of optical device layers divided into chip sizes on the front surface of an epitaxial substrate with a buffer layer interposed therebetween. The method for transferring the optical device layer includes the following steps: a transfer member bonding step of bonding the optical device wafer and a transfer member with an adhesive, and filling the adhesive into the gap between the optical device layers divided into chip sizes in the optical device wafer; a buffer layer destruction step of, after performing the transfer member bonding step, irradiating a pulsed laser beam having a wavelength that is transmissive to the epitaxial substrate and absorptive to the buffer layer from the back side of the epitaxial substrate of the optical device wafer to which the transfer member is bonded, to destroy the buffer layer; an optical device layer transfer step of, after performing the buffer layer destruction step, peeling the epitaxial substrate from the optical device layer, and transferring the optical device layer laminated on the epitaxial substrate to the transfer member; an adhesive removal step of, after the optical device layer transfer step, removing at least a part of the adhesive filled into the gap between the optical device layers so that the optical device layer embedded in the adhesive layer by the transfer member bonding step protrudes from the adhesive layer; and an optical device layer transfer step of, after the adhesive removal step, transferring the optical device layer protruding from the adhesive layer to a mounting substrate.

[0009] According to the invention of the present application, the transfer rate of the optical device to the transfer member can be suppressed from decreasing during laser lift-off. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a perspective view of an optical device wafer to be transferred, which includes the transfer method of the embodiment of the present invention.

[0011] Figure 2 is Figure 1 a cross-sectional view of the optical device wafer.

[0012] Figure 3 is a flowchart showing the transfer method of the embodiment.

[0013] Figure 4 is a cross-sectional view showing Figure 3 a state of the transfer member bonding step.

[0014] Figure 5 is a cross-sectional view showing Figure 3 a state Figure 4 after the transfer member bonding step.

[0015] Figure 6 is a cross-sectional side view showing Figure 3 an example of the buffer layer destruction step.

[0016] Figure 7Is a cross-sectional view showing an example of the step of transferring the optical device layer Figure 3 as shown in Figure 3 .

[0017] Figure 8 Is a partial cross-sectional side view showing an example of the step of removing the adhesive Figure 3 as shown in Figure 3 .

[0018] Figure 9 Is a cross-sectional view showing a state of the step of transferring the optical device layer Figure 3 as shown in Figure 3 .

[0019] Figure 10 Is a cross-sectional view showing a state after the step of transferring the optical device layer Figure 3 as shown in Figure 3 . Figure 9 after the step of transferring the optical device layer as shown in Figure 3 .

[0020] Reference numeral description

[0021] 1: Optical device wafer; 2: Epitaxial substrate; 3: Front surface; 4: Buffer layer; 5: Optical device layer; 7: Optical device; 8: Back surface; 11: Transfer member; 12: Adhesive; 100: Mounting substrate. Detailed description of the specific embodiment

[0022] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the content described in the following embodiments. In addition, among the constituent elements described below, there are those that can be easily conceived by those skilled in the art and those that are substantially the same. In addition, the structures described below can be appropriately combined. In addition, various omissions, replacements, or changes in the structure can be made without departing from the gist of the present invention.

[0023] [Embodiment]

[0024] A transfer method according to an embodiment of the present invention will be described with reference to the drawings. Figure 1 Is a perspective view of an optical device wafer 1 which is an object to be transferred including the transfer method of the embodiment. Figure 2 Is Figure 1 a cross-sectional view of the optical device wafer 1 as shown in Figure 1 . In addition, Figure 1 and Figure 2 in Figure 1 and Figure 2 , for the purpose of explaining this embodiment, the optical device layer 5 etc. are schematically shown to be larger than the actual size with respect to the optical device wafer 1, and the same applies to the subsequent drawings. As Figure 2 shown in Figure 2 , the optical device wafer 1 includes an epitaxial substrate 2 and an optical device layer 5 laminated on the front surface 3 side of the epitaxial substrate 2 with a buffer layer 4 interposed therebetween.

[0025] In this embodiment, the epitaxial substrate 2 is a sapphire substrate having a disc shape with a diameter of about 2 inches (about 50 mm) and a thickness of about 300 μm. In this embodiment, as Figure 2As shown, the optical device layer 5 is an n-type gallium nitride semiconductor layer 5-1 and a p-type gallium nitride semiconductor layer 5-2 formed on the front surface 3 of the epitaxial substrate 2 by epitaxial growth method with a total thickness of about 6 μm, and is used as an LED (Light Emitting Diode), for example. In the embodiment, the buffer layer 4 is a gallium nitride (GaN) layer with a thickness of about 1 μm formed between the front surface 3 of the epitaxial substrate 2 and the p-type gallium nitride semiconductor layer 5-2 of the optical device layer 5 when the optical device layer 5 is stacked on the epitaxial substrate 2.

[0026] In the present embodiment, as Figure 1 shown, the optical device layer 5 is divided and stacked in a chip size in a plurality of regions divided by a plurality of spacer channels 6 intersecting in a lattice shape to form an optical device 7. The interval between the optical device layers 5, that is, the interval between the optical devices 7 is the same as the width of the spacer channel 6, which is about 5 μm in the present embodiment. In addition, the size of the optical device layer 5, that is, the size of the optical device 7 is the same as the interval between the spacer channels 6, which is 10 μm or more and 20 μm or less in the present embodiment. That is, in the present embodiment, about 2 million optical devices 7 used as micro LEDs are formed on the epitaxial substrate 2 with a diameter of 2 inches.

[0027] Next, the transfer method of the embodiment will be described. Figure 3 is a flowchart showing the transfer method of the embodiment. The transfer method is a transfer method for transferring the optical device layer 5 of the optical device wafer 1. As Figure 3 shown, the transfer method includes a transfer component bonding step ST11, a buffer layer breaking step ST12, an optical device layer transfer step ST13, an adhesive removing step ST14, and an optical device layer transfer step ST15.

[0028] Figure 4 is a cross-sectional view showing Figure 3 a state of the transfer component bonding step ST11. Figure 5 is a cross-sectional view showing Figure 3 a state of the transfer component bonding step ST11 of Figure 4 after. As Figure 4 and Figure 5 shown, the transfer component bonding step ST11 is a step of bonding the optical device wafer 1 and the transfer component 11 with an adhesive 12 and filling the gap between the optical device layers 5 divided into chip sizes in the optical device wafer 1 with the adhesive 12.

[0029] In the transfer component bonding step ST11, specifically, as Figure 4As shown, first, a transfer substrate having the same size as the epitaxial substrate 2 is prepared as the transfer member 11, and an adhesive 12 is coated on one surface of the transfer member 11. The adhesive 12 has a volume equal to or greater than the total volume of the spacer channels 6 corresponding to the gaps between the optical device layers 5.

[0030] In addition, in the present embodiment, the transfer member 11 uses a glass substrate having a thickness of about 0.3 mm, which is the same degree as the epitaxial substrate 2, as an appropriate substrate. However, the present invention is not limited thereto, and any other substrate made of various materials such as a metal substrate can be used as long as it can be bonded to the adhesive 12 composed of an organic compound.

[0031] In addition, the adhesive 12 uses an adhesive composed of an organic compound, such as a paste used in an adhesive tape, as an appropriate adhesive. The adhesive 12 has the following properties: it softens upon heating, reducing its viscosity, and undergoes a chemical reaction such as a hardening reaction upon further heating or ultraviolet irradiation, thereby hardening and further reducing its viscosity.

[0032] In the transfer member bonding step ST11, next, the optical device layer 5 laminated on the epitaxial substrate 2 is opposed to the adhesive 12 coated on the transfer member 11, and they are brought close to each other and contacted. In the transfer member bonding step ST11, further pressing is performed from the back surface 8 side, which is the side opposite to the front surface 3 of the epitaxial substrate 2, toward the transfer member 11, or from the side of the transfer member 11 opposite to the side coated with the adhesive 12 toward the epitaxial substrate 2, so that Figure 5 As shown, the adhesive 12 is deformed along the optical device layer 5 so that the optical device layer 5 completely enters the adhesive 12. Thus, in the transfer member bonding step ST11, the adhesive 12 is filled in the gaps between the optical device layers 5 of the optical device wafer 1 divided into chip sizes.

[0033] Here, in the transfer member bonding step ST11, regarding the pressing force, the stronger the better as long as the optical device wafer 1 and the transfer member 11 are not damaged. In this case, by deforming the adhesive 12 more appropriately along the optical device layer 5, the gaps between the optical device layers 5 can be filled more appropriately. In addition, in the transfer member bonding step ST11, it is preferable to heat from the back surface 8 side of the epitaxial substrate 2 or the transfer member 11 to such an extent that the adhesive 12 does not undergo a chemical reaction such as a hardening reaction. In this case, the viscosity of the adhesive 12 decreases, so that by deforming the adhesive 12 more appropriately along the optical device layer 5, the gaps between the optical device layers 5 can be filled more appropriately.

[0034] Figure 6 is shown Figure 3A partial cross-sectional side view of an example of the buffer layer destruction step ST12. As Figure 6 shown, in the buffer layer destruction step ST12, after the transfer component bonding step ST11 is performed, pulsed laser light 34 having a wavelength that is transmissive to the epitaxial substrate 2 and absorptive to the buffer layer 4 is irradiated from the back surface 8 side of the epitaxial substrate 2 of the optical device wafer 1 to which the transfer component 11 is bonded, thereby destroying the buffer layer 4.

[0035] In the buffer layer destruction step ST12, specifically, as Figure 6 shown, first, the surface on the transfer component 11 side of the assembly of the optical device wafer 1 and the transfer component 11 bonded through the transfer component bonding step ST11 is attracted and held by the holding surface 21 of the chuck table 20 connected to a vacuum source (not shown).

[0036] In the buffer layer destruction step ST12, then, the pulsed laser light 34 having a wavelength that is transmissive to the epitaxial substrate 2 and absorptive to the buffer layer 4 is irradiated from the back surface 8 side of the epitaxial substrate 2 of the assembly of the optical device wafer 1 and the transfer component 11 held by the chuck table 20, thereby destroying the buffer layer 4. In the present embodiment, the pulsed laser light 34 is irradiated over the entire surface of the epitaxial substrate 2 in the buffer layer destruction step ST12, but the present invention is not limited thereto, and the pulsed laser light 34 may be irradiated only at the position where the buffer layer 4 is formed on the epitaxial substrate 2.

[0037] Here, as Figure 6 shown, the laser light irradiation unit 30 generates the pulsed laser light 34 of the above-described specified wavelength by the laser light generation unit 31, changes the direction of the pulsed laser light 34 from the laser light generation unit 31 to a direction perpendicular to the back surface 8 of the epitaxial substrate 2 of the assembly held by the chuck table 20 through the optical reflector 32, and converges the pulsed laser light 34 from the optical reflector 32 through the condenser lens 33 to adjust the spot diameter and defocus of the pulsed laser light 34, thereby adjusting the irradiation conditions of the pulsed laser light 34 in the buffer layer destruction step ST12.

[0038] In the buffer layer destruction step ST12, for example, ultraviolet laser light having a wavelength of about 257 nm with a repetition frequency of 50 kHz or more and 200 kHz or less, an average output of 0.1 W or more and 2.0 W or less, and a pulse width of 20 ps or less is used as the pulsed laser light 34, the spot diameter is set to 10 μm or more and 50 μm or less, and the defocus is adjusted to about 1.0 mm to perform the destruction process of the buffer layer 4.

[0039] Figure 7 shows Figure 3A perspective view of an example of the optical device layer transfer step ST13. The optical device layer transfer step ST13 is a step of peeling the epitaxial substrate 2 from the optical device layer 5 after performing the buffer layer destruction step ST12 and transferring the optical device layer 5 originally stacked on the epitaxial substrate 2 to the transfer member 11.

[0040] In the optical device layer transfer step ST13, specifically, ultrasonic vibration is applied from the back surface 8 side of the epitaxial substrate 2 of the bonded body in which the buffer layer 4 is destroyed by the buffer layer destruction step ST12 through a horn provided with an ultrasonic vibration unit (not shown), so that the epitaxial substrate 2 is peeled from the optical device layer 5 starting from the destroyed buffer layer 4, and the optical device layer 5 is transferred to the transfer member 11.

[0041] In this way, by performing so-called laser lift-off based on the buffer layer destruction step ST12 and the optical device layer transfer step ST13, the optical device layer 5 (optical device 7) is embedded and transferred into the adhesive 12 formed by coating one surface of the transfer member 11. Figure 7 The optical device layer transfer substrate 10 shown.

[0042] Figure 8 It is a perspective view showing an example of Figure 3 the adhesive removal step ST14. As Figure 8 shown, the adhesive removal step ST14 is a step of removing at least a part of the adhesive 12 filled in the gap between the optical device layers 5 so that the optical device layer 5 embedded in the adhesive layer as the adhesive 12 protrudes from the adhesive layer through the transfer member bonding step ST11.

[0043] In the adhesive removal step ST14, specifically, first as Figure 6 shown, the surface on the transfer member 11 side of the optical device layer transfer substrate 10 obtained through the optical device layer transfer step ST13 is sucked and held by the holding surface 21 of the chuck table 20. In the adhesive removal step ST14, alignment is then performed, that is, the alignment of the irradiation position of the laser beam 41 of the laser beam irradiation unit 40 and the optical device layer transfer substrate 10 held by the holding surface 21 of the chuck table 20 is carried out.

[0044] In addition, in the present embodiment, the laser beam irradiation unit 40 used in the adhesive removal step ST14 is different from the laser beam irradiation unit 30 used in the buffer layer destruction step ST12. However, in the present invention, this is not limited thereto, and the same laser beam irradiation unit can be used in the buffer layer destruction step ST12 and the adhesive removal step ST14.

[0045] In the adhesive removing step ST14, then, from the side where the optical device layer 5 (optical device 7) is transferred in the adhesive 12 of the optical device layer transfer substrate 10, the laser beam 41 is irradiated to at least a part of the adhesive 12 between the optical device layers 5 (optical device 7) while avoiding the irradiation of the laser beam 41 to the optical device layer 5 (optical device 7), and the adhesive 12 is selectively laser ablated and removed.

[0046] In the adhesive removing step ST14, for example, a laser beam in the ultraviolet region to visible light region with a repetition frequency of 100 kHz or more and 1000 kHz or less, an average output of 0.2 W or more and 1.5 W or less, and a wavelength of about 257 nm or more and about 515 nm or less is used as the laser beam 41. The spot diameter is reduced to 0.5 μm or more and 3 μm or less, and such a laser beam 41 is scanned on the adhesive 12 at 100 mm / s or more and 600 mm / s or less, thereby performing the removal process of the adhesive 12.

[0047] In the adhesive removing step ST14, it is preferable that the removal thickness 12-1 of the adhesive 12 is more than half of the thickness of the optical device layer 5 (optical device 7). In this case, in the subsequent optical device layer transfer step ST15, the optical device layer 5 (optical device 7) can be appropriately picked up from the adhesive 12. In addition, in the adhesive removing step ST14, it is preferable that the removal thickness 12-1 of the adhesive 12 is less than the amount reaching the depth of the transfer member 11. In this case, the possibility of laser ablation of the transfer member 11 by the laser beam 41 can be suppressed.

[0048] In addition, in the adhesive removing step ST14, it is preferable that the removal thickness 12-1 of the adhesive 12 is within a specified range, and more preferably, the removal thickness 12-1 of the adhesive 12 is constant. In these cases, in the subsequent optical device layer transfer step ST15, the optical device layer 5 (optical device 7) can be stably picked up from the adhesive 12 with a force within a specified range.

[0049] In the present embodiment, the area where the optical device layer 5 (optical device 7) is transferred is about 10 μm or more and 20 μm or less, the area where the adhesive 12 is exposed is about 5 μm, which is the same as the width of the isolation channel 6, and the removal thickness 12-1 of the adhesive 12 is about 3 μm, which is about the same as half of the thickness of the optical device layer 5 (optical device 7). In the adhesive removing step ST14, since laser ablation is performed by the laser beam 41, the removal area 12-2 and the removal thickness 12-1 of the adhesive 12 in the order of μm as in the present embodiment can be controlled.

[0050] In the present embodiment, the regions where the optical device layer 5 (optical device 7) is transferred and the regions where the adhesive 12 is exposed are arranged periodically. Therefore, in the adhesive removal step ST14, it is preferable to remove the adhesive 12 by, for example, so-called Hasen Cut (registered trademark) in which the laser beam 41 is turned on and off repeatedly according to a set period while performing laser ablation processing, or by scanning the laser beam 41 using a scanning unit having an electric scanner, a resonant scanner, an acousto-optic deflector, or a polygon mirror. In the adhesive removal step ST14, specifically, the laser beam 41 is irradiated while repeating the opening and closing. For example, in the regions where the adhesive 12 is exposed, the laser beam 41 is irradiated in an open state, and in the regions where the optical device layer 5 (optical device 7) is transferred, the laser beam 41 is turned off and passed through.

[0051] Figure 9 is a cross-sectional view showing Figure 3 a state of the optical device layer transfer step ST15. Figure 10 is a cross-sectional view showing Figure 3 a state after the optical device layer transfer step ST15 of Figure 9 As shown in Figure 9 and Figure 10 the optical device layer transfer step ST15 is a step of transferring the optical device layer 5 protruding from the adhesive layer to the mounting substrate 100 after the adhesive removal step ST14.

[0052] In the optical device layer transfer step ST15, specifically, it is first preferable to perform an adhesiveness reduction treatment for reducing the adhesiveness of the adhesive 12 that supports the optical device layer 5 (optical device 7) before picking up each optical device layer 5 (optical device 7) using the picking portions 51 arranged in a row at positions facing the optical device layer 5 (optical device 7) of the picking unit 50. The adhesiveness reduction treatment is, for example, a treatment for reducing the viscosity of the adhesive 12 by heating the adhesive 12, or a treatment for reducing the adhesiveness of the adhesive 12 by irradiating the adhesive 12 with ultraviolet rays or further heating to cause a hardening reaction such as a polymerization reaction, so that the optical device layer 5 (optical device 7) can be picked up with a lower force using the picking unit 50, the picking accuracy can be improved, and the remaining adhesive 12 on the optical device layer 5 (optical device 7) can be reduced and suppressed.

[0053] In the optical device layer transfer step ST15, then, as shown in Figure 9 each optical device layer 5 (optical device 7) is picked up by gripping or adsorbing and holding it using each picking portion 51 of the picking unit 50. In the optical device layer transfer step ST15, then, as shown in Figure 10As shown, each optical device layer 5 (optical device 7) picked up by each picking part 51 of the picking unit 50 is moved and placed on the bonding layer 110 arranged on the mounting substrate 100 in the same shape, size, interval, etc. as the optical device layer 5 (optical device 7).

[0054] Each optical device layer 5 (optical device 7) transferred to the bonding layer 110 of the mounting substrate 100 by the optical device layer transfer step ST15 is bonded and mounted on the mounting substrate 100 by means of the bonding layer 110.

[0055] In this way, in the optical device layer transfer step ST15, in the present embodiment, each optical device layer 5 (optical device 7) protruding from the adhesive 12 is transferred to the mounting substrate 100 in a one-time manner over the entire surface by each picking part 51 of the picking unit 50, so that the optical device layer 5 (optical device 7) can be transferred efficiently. In addition, in the present invention, not limited to this, each optical device layer 5 (optical device 7) protruding from the adhesive 12 can also be transferred to the mounting substrate 100 one by one by using one picking part 51. In this case, the transfer accuracy of each optical device layer 5 (optical device 7) can be improved.

[0056] In the transfer method of transferring the optical device layer 5 of the optical device wafer 1 in the embodiment, in the transfer component bonding step ST11, the state is such that the adhesive 12 is filled in the gap between the optical device layers 5 of the optical device wafer 1 divided into chip sizes, and the optical device wafer 1 and the transfer component 11 are bonded by means of the adhesive 12. Therefore, the following effects are achieved: when laser lift-off is performed, the transfer rate of the optical device 7 to the transfer component 11 (optical device layer 5) can be suppressed from decreasing.

[0057] In addition, in the transfer method of transferring the optical device layer 5 of the optical device wafer 1 in the embodiment, at least a part of the adhesive 12 filled in the gap between the optical device layers 5 is removed in the adhesive removal step ST14, so that the optical device layer 5 embedded in the adhesive layer in the transfer component bonding step ST11 protrudes from the adhesive layer. Therefore, the following effects are achieved: the transfer efficiency and transfer accuracy of transferring the optical device layer 5 (optical device 7) to the mounting substrate 100 can be suppressed from decreasing.

[0058] [Modification Example]

[0059] The transfer method of the modification example of the embodiment of the present invention will be described. The transfer method of the modification example is the same as that of the embodiment except that the adhesive removal step ST14 is different.

[0060] In the adhesive removal step ST14 of the modification example, the adhesive 12 is selectively removed by using an etching process or a scribing process instead of the irradiation of the laser beam 41 in the embodiment.

[0061] In the adhesive removing step ST14 of the modified example, an etchant containing a compound of a liquid or a gas that removes the adhesive 12 by a chemical reaction with the adhesive 12 and hardly causes a significant chemical reaction with the optical device layer 5 is provided toward the optical device layer 5 and the adhesive 12, so that the adhesive 12 is selectively removed by an etching process.

[0062] Further, in the adhesive removing step ST14 of the modified example, for example, a scriber using a tool made of metal, diamond, or the like with a tip diameter of about several μm or less that is the same as or smaller than the exposed area of the adhesive 12 and the width of the isolation trench 6 is used to cut the exposed area of the adhesive 12 along the isolation trench 6, so that the adhesive 12 is selectively removed by a scribing process.

[0063] The transfer method for transferring the optical device layer 5 of the optical device wafer 1 in these modified examples has the same effect as the transfer method for transferring the optical device layer 5 of the optical device wafer 1 in the embodiment.

[0064] In addition, the present invention is not limited to the above-described embodiment. That is, various modifications can be made and implemented without departing from the gist of the present invention.

Claims

1. A method for transferring an optical device layer, which transfers the optical device layer of an optical device wafer. The optical device wafer is obtained by laminating a plurality of optical device layers of chip size with a buffer layer interposed therebetween on the front surface of an epitaxial substrate. Among them, The method for transferring the optical device layer has the following steps: Transfer component bonding step: bonding the optical device wafer and the transfer component with an adhesive, and filling the adhesive into the gap between the optical device layers of chip size in the optical device wafer; Buffer layer destruction step: after performing the transfer component bonding step, irradiating the buffer layer with pulsed laser light of a wavelength that is transmissive to the epitaxial substrate and absorptive to the buffer layer from the back side of the epitaxial substrate of the optical device wafer bonded with the transfer component to destroy the buffer layer; Optical device layer transfer step: after performing the buffer layer destruction step, peeling the epitaxial substrate from the optical device layer and transferring the optical device layer laminated on the epitaxial substrate to the transfer component; Adhesive removal step: after the optical device layer transfer step, removing at least a part of the adhesive filled in the gap between the optical device layers so that the optical device layer embedded in the adhesive layer by the transfer component bonding step protrudes from the adhesive layer; And Optical device layer transfer step: after the adhesive removal step, transferring the optical device layer protruding from the adhesive layer to the mounting substrate, In the adhesive removal step, irradiating at least a part of the adhesive between the optical device layers with laser light while avoiding irradiating the optical device layer with the laser light, and selectively removing the adhesive.

2. The method for transferring an optical device layer according to claim 1, wherein, In the transfer component bonding step, heating the adhesive to reduce the viscosity of the adhesive, and deforming the adhesive along the optical device layer, so as to fill the adhesive into the gap between the optical device layers.

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