TW202239021A - Workpiece handling sheet and device manufacturing method - Google Patents

Abstract

Provided is a workpiece handling sheet 1 comprising: a substrate 12; and a resin layer 11 which is laminated on one surface of the substrate 12 and which can hold small workpieces, wherein the resin layer 11 contains 10 mass% or more of a laser beam absorbing component having absorbing properties relative to laser beam wavelengths, and the resin layer 11 performs full ablation by laser beam irradiation. This workpiece handling sheet allows for proper handling even of very small workpieces.

Description

Workpiece processing sheet and device manufacturing method

The present invention relates to a workpiece processing sheet that can be used for processing small workpieces such as semiconductor elements and semiconductor devices, and a device manufacturing method using the workpiece processing sheet, especially for processing micro light emitting diodes, power elements, MEMS (Micro Electro A workpiece processing sheet that can be used for small workpieces such as Mechanical Systems, and a method for manufacturing a device using the workpiece processing sheet.

In recent years, the development of displays using micro light emitting diodes is advancing. In the display, each pixel is composed of micro-light-emitting diodes, and the light-emitting system of each micro-light-emitting diode is independently controlled. In the manufacture of such a display, generally, micro light emitting diodes arranged on a supply substrate such as sapphire or glass need to be mounted on a wiring substrate provided with wiring.

During the above-mentioned mounting, it is necessary to accurately mount the plurality of micro light-emitting diodes disposed on the supply substrate on a predetermined position of the wiring substrate. In this case, it is necessary to selectively mount a designated one among the plurality of micro light emitting diodes on the wiring board, or to simultaneously mount a plurality of micro light emitting diodes.

From the viewpoint of performing such mounting well, the use of irradiation with laser light has been considered. For example, after a plurality of micro light-emitting diodes are held on a support body through a predetermined layer, the layer is irradiated with laser light, whereby the ablation of the layer occurs in the irradiated position, whereby the already A method of placing micro light emitting diodes separated from a support (laser lift-off) on a wiring board (Patent Document 1). Since laser light is excellent in directivity and convergence, it is easy to control the position of irradiation, and it is possible to perform selective placement well. [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent No. 6546278

[Problem to be solved by the invention]

However, further miniaturization of micro-light emitting diodes, higher-density mounting of micro-light-emitting diodes, etc. are also being developed, and on the premise that they are also compatible with these, a means is required, which is different from that of patent document 1. The conventional method can more efficiently process small workpieces such as multiple micro-light-emitting diodes.

The present invention was made in view of such actual conditions, and an object of the present invention is to provide a workpiece processing sheet capable of processing fine workpiece processing sheets satisfactorily, and a device manufacturing method using the workpiece processing sheet. [means used to solve a problem]

In order to achieve the above object, first, the present invention provides a workpiece processing sheet, which is a workpiece processing sheet having a base material and a resin layer, the resin layer is laminated on one side of the base material and can hold a small workpiece, so The workpiece processing sheet is characterized in that the resin layer contains at least 10% by mass of a laser light absorbing component absorbing the wavelength of laser light, and the resin layer is completely ablated by irradiation of the laser light (Invention 1) .

In the workpiece processing sheet of the above-mentioned invention (Invention 1), the total ablation is effectively performed when the laser light is irradiated by the resin layer containing the laser light-absorbing component having absorption properties at the wavelength of laser light in the above-mentioned amount, In this way, the workpiece small pieces can be well separated toward the target object.

Second, the present invention provides a workpiece processing sheet, which is a workpiece processing sheet having a base material and a resin layer, the resin layer is laminated on one side of the base material and can hold a small workpiece, and the workpiece processing sheet It is characterized in that the above-mentioned resin layer contains a laser light-absorbing component having absorptivity to the wavelength of laser light, where the content of the above-mentioned laser light-absorbing component in the above-mentioned resin layer is X mass % and the thickness of the above-mentioned resin layer is Y μm In this case, the value of dividing X by Y (X/Y) is 2.0 or more (invention 2).

In the workpiece processing sheet of the above-mentioned invention (Invention 2), the resin layer contains a laser light-absorbing component that absorbs the wavelength of laser light so that the resin layer satisfies the above-mentioned conditions related to the thickness of the resin layer. In this case, total ablation is effectively performed, whereby the workpiece small pieces can be well separated toward the target object.

In the above inventions (Inventions 1 and 2), it is preferable that the laser light absorbing component is at least one of an ultraviolet absorber and a photopolymerization initiator (Invention 3).

In the above invention (Invention 3), it is preferable that the ultraviolet absorber is an organic compound (Invention 4).

In the above inventions (Inventions 3 and 4), it is preferable that the ultraviolet absorber is a compound having one or more heterocycles (Invention 5).

In the above inventions (Inventions 3 to 5), preferably, the ultraviolet absorber has at least one of a carbocycle and a heterocycle, and all the carbocycles and heterocycles in the ultraviolet absorber are monocyclic rings (Invention 6). ).

In the above inventions (Inventions 3 to 6), it is preferable that the ultraviolet absorber is a compound having a plurality of aromatic rings (Invention 7).

In the above inventions (Inventions 1 to 7), it is preferable that the resin layer is an adhesive layer (Invention 8).

In the above invention (Invention 8), it is preferable that the adhesive constituting the adhesive layer is an acrylic adhesive (Invention 9).

In the above inventions (Inventions 1 to 9), it is preferable that the laser light has a wavelength in the ultraviolet region (Invention 10).

In the above inventions (Inventions 1 to 10), it is preferable to selectively separate and hold in the resin layer from the resin layer by total ablation locally occurring in the resin layer opposite to the base material. Any one of the plurality of workpiece small pieces on the surface is used (invention 11).

In the above invention (Invention 11), it is preferable that the workpiece piece is obtained by singulating the workpiece held on the surface of the resin layer opposite to the base material on the surface (Invention 12) .

In the above inventions (Inventions 11 and 12), it is preferable that the workpiece chip is at least one selected from a semiconductor element and a semiconductor device (Invention 13).

In the above inventions (Inventions 11-13), it is preferable that the aforementioned workpiece chip is a light-emitting diode selected from submillimeter light-emitting diodes (mini LEDs) and micro-light-emitting diodes (micro LEDs) (Invention 14).

Third, the present invention provides a device manufacturing method characterized by comprising: a preparatory step of preparing a layered body, the layered system holding a plurality of workpiece small pieces in the aforementioned resin in the aforementioned workpiece processing sheet (Inventions 1 to 14) forming on the surface of the layer side; arranging the step of arranging the laminated body in such a manner as to face the surface of the aforementioned laminated body on the side of the aforementioned workpiece small piece with respect to the object capable of accommodating the aforementioned workpiece small pieces; Laser light is irradiated on the position of the aforementioned resin layer in the laminated body where at least one of the aforementioned workpiece small pieces is attached, and total ablation occurs at the aforementioned irradiated position in the aforementioned resin layer, whereby the workpiece processing piece is separated from the aforementioned workpiece processing piece. The workpiece small piece at the position where the total ablation occurs is placed on the object (invention 15).

In the above invention (Invention 15), it is preferable that, in the preparation step, the workpiece held on the surface of the resin layer opposite to the substrate is singulated on the surface to obtain the workpiece. Small tablets (invention 16).

In the above inventions (Inventions 15 and 16), it is preferable that the workpiece chip is at least one selected from a semiconductor element and a semiconductor device (Invention 17).

In the above-mentioned inventions (Inventions 15-17), it is preferable to use a light-emitting diode selected from submillimeter light-emitting diodes and micro-light-emitting diodes as the aforementioned workpiece chip, and to manufacture a light emitting diode having a plurality of the aforementioned light-emitting diodes. device (invention 18).

In the above invention (Invention 18), it is preferable that the light emitting device is a display (Invention 19). [Efficacy of the invention]

The workpiece processing sheet of the present invention can handle fine workpieces well, and according to the device manufacturing method of the present invention, a device having excellent performance can be manufactured.

[For Embodiment of Invention]

Embodiments of the present invention will be described below. In Fig. 1, a cross-sectional view of a workpiece processing sheet according to an embodiment is disclosed. The workpiece processing sheet 1 shown in FIG. 1 includes a base material 12 and a resin layer 11 laminated on one side of the base material 12 .

In the workpiece processing sheet 1 of this embodiment, the resin layer 11 can hold the workpiece small pieces. That is, the workpiece processing sheet 1 of this embodiment can hold the workpiece small piece laminated on the surface of the resin layer 11 opposite to the base material 12 as it is.

The specific aspect of the above-mentioned holding is not limited, but as a preferable example, holding by the resin layer 11 exerting adhesiveness to the workpiece piece can be mentioned. In this case, the resin layer 11 is preferably one containing an adhesive as one of its constituent components as will be described later, that is, an adhesive layer.

Furthermore, in the workpiece processing sheet 1 of the present embodiment, it is preferable that the resin layer 11 contains a laser light absorbing component that absorbs the wavelength of laser light in an amount of 10% by mass or more, and the total ablation is performed by irradiation of laser light. (Hereafter, these conditions may be referred to as "Condition 1").

In addition, in the workpiece processing sheet 1 of this embodiment, it is also preferable that the resin layer 11 contains a laser light absorbing component that absorbs the wavelength of laser light, and the content of the laser light absorbing component in the resin layer 11 In the case of X mass % and the thickness of the resin layer 11 being Y μm, the value (X/Y) of dividing X by Y is 2.0 or more (hereinafter, these conditions may be referred to as "Condition 2" ).

The workpiece processing sheet 1 of the present embodiment satisfies at least one of the above-mentioned condition 1 and condition 2, so that the total ablation can be performed satisfactorily when irradiated with laser light.

In this specification, the so-called total ablation means that the components constituting the resin layer 11 are evaporated or volatilized by the energy of the laser light, whereby the parts of the resin layer 11 irradiated with the laser light disappear. In addition, when this disappears, the components constituting the resin layer 11 may or may not be decomposed. And, the workpiece small pieces that originally existed in the above-mentioned disappearing positions lose their existence and become separated from the workpiece processing piece 1 of this embodiment.

As a conventional workpiece processing sheet, there is a workpiece processing sheet that generates voids at the interface between the base material and the resin layer by irradiation of laser light, thereby expanding the resin layer and separating workpiece small pieces. On the other hand, in the workpiece processing chip 1 of this embodiment, since the expansion of the resin layer does not occur, the workpiece small pieces can be separated, so when separating, the workpiece small pieces and the object receiving the workpiece small pieces can be shortened. distance. Therefore, the positional accuracy at the time of separating the object from the workpiece small piece is extremely high.

Furthermore, since the workpiece processing sheet 1 of this embodiment satisfies the condition 1 or the condition 2 and contains a laser light absorbing component at the same time, the efficiency of the resin layer 11 to receive energy from the laser light is improved. Thereby, total ablation occurs efficiently, and it becomes possible to separate the workpiece|work small piece held|maintained from the resin layer 11 favorably. In particular, the amount of laser light irradiation required to sufficiently separate the workpiece small pieces can be reduced, and the operating cost of the laser light irradiation device can be reduced. At the same time, it becomes easy to separate only the target workpiece small pieces well, and the accuracy can be improved. Improvement, moreover, can also prevent damage to devices and workpiece chips caused by excessive laser light irradiation.

In addition, as the above-mentioned laser light, it is not particularly limited as long as total ablation can occur, and it may be a laser light having any wavelength in the ultraviolet region, visible light region, and infrared region, and among them, one of the wavelengths in the ultraviolet region is preferable. laser.

1. Resin layer The specific configuration, composition, etc. of the resin layer 11 in this embodiment are not particularly limited as long as it can hold the workpiece piece and satisfies at least one of the conditions 1 and 2.

The resin layer 11 preferably contains an adhesive as one of its constituent components, as described above, from the viewpoint of easily exhibiting the property capable of holding the workpiece small pieces well. When the resin layer 11 includes an adhesive, the resin layer 11 is preferably composed of an adhesive composition containing a laser light absorbing component.

(1) Laser light absorbing components The above-mentioned laser light absorbing component is not particularly limited as long as it absorbs the wavelength of laser light, but is preferably at least one of an ultraviolet absorber and a photopolymerization initiator.

(1-1) UV absorber The kind of the above-mentioned ultraviolet absorber is not particularly limited. The ultraviolet absorber in this embodiment may be an organic compound or an inorganic compound, but is preferably an organic compound from the viewpoint that good total ablation is likely to occur.

In the case where the ultraviolet absorber is an organic compound, preferred examples of the ultraviolet absorber include hydroxyphenyltriazole-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and benzotriazole-based ultraviolet absorbers. Formic acid-based UV absorber, benzophenone-based UV absorber, phenyl salicylate-based UV absorber, cyanoacrylate-based UV absorber, nickel zirconium salt-based UV absorber, hydroquinone-based UV absorber, willow Compounds such as acid-based ultraviolet absorbers, malonate-based ultraviolet absorbers, and oxalic acid-based ultraviolet absorbers. These may be used alone or in combination of two or more.

Among the above-mentioned ultraviolet absorbers, it is preferable to use the hydroxyphenyl tri-sulphur-based ultraviolet absorber from the viewpoint of good absorption in the third harmonic (355nm) of YAG and good total ablation easily. At least one of UV absorbers, diphenyl ketone-based UV absorbers, and benzotriazole-based UV absorbers, particularly preferably hydroxyphenyltriazole-based UV absorbers.

Examples of the above-mentioned hydroxyphenyl trioxane-based ultraviolet absorbers include 2-[4-(octyl-2-methyl acetate)oxy-2-hydroxyphenyl]-4,6-[bis(2,4- Dimethylphenyl)]-1,3,5-trimethanone, 2-[4-(2-hydroxy-3-dodecyloxy-propyl)oxy-2-hydroxyphenyl]-4, 6-[bis(2,4-dimethylphenyl)-1,3,5-trimethanone, 2-[4-(2-hydroxy-3-tridecyloxy-propyl)oxy-2 -Hydroxyphenyl]-4,6-[bis(2,4-dimethylphenyl)-1,3,5-trimethylphenyl, 2-(2,4-dihydroxyphenyl)-4,6- Bis-(2,4-Dimethylphenyl)-1,3,5-Trisyloxy]-2-[4-(2-Hydroxy-3-(2'-Ethyl)hexyloxy]-2-Hydroxy Phenyl]-4,6-[bis(2,4-dimethylphenyl)-1,3,5-trimethanone, 2,4-bis[2-hydroxy-4-butoxyphenyl]- 6-(2,4-dibutoxyphenyl)-1,3-5-trimethanone, 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4 ,6-bis(4-phenylphenyl)-1,3,5-trimethanone, ginseng[2,4,6-[2-{4-(octyl-2-methyl acetate)oxy-2 -Hydroxyphenyl}]-1, 3, 5-triphenylene, etc. These can be used alone or in combination of two or more. Among them, it is preferable to use the reference [2, 4, 6- [2-{4-(octyl-2-methyl acetate)oxy-2-hydroxyphenyl}]-1,3,5-trisalpine and 2-(2-hydroxy-4-[1-octyl At least one of oxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triphenyl.

Furthermore, when the ultraviolet absorber is an organic compound, the ultraviolet absorber is preferably a compound having one or more heterocyclic rings as a characteristic of its chemical structure. In this case, the number of heterocycles is preferably 4 or less, particularly preferably 1.

And, as another chemical structural feature, the ultraviolet absorber in this embodiment preferably has at least one of carbocycle and heterocycle, and all the carbocycles and heterocycles possessed by the ultraviolet absorber are respectively single ring.

As a further chemical structural feature, the ultraviolet absorber in this embodiment is also preferably a compound having a plurality of aromatic rings. In this case, the number of aromatic rings is preferably two or more. In addition, the number of aromatic rings is preferably 6 or less, particularly preferably 3 or less.

Among the above-mentioned chemical structural features, each heterocycle preferably has at least one selected from nitrogen, oxygen, phosphorus, sulfur, silicon, and selenium as an element other than carbon constituting it, and particularly preferably has an element selected from At least one selected from nitrogen, oxygen, phosphorus and sulfur. Furthermore, the number of atoms constituting the ring structure of the heterocyclic ring is not particularly limited, and is, for example, 3 or more and 9 or less, particularly preferably 5 or more and 6 or less. Specific examples of preferable heterocyclic rings include trioxane, benzotriazole, thiophene, pyrrole, imidazole, pyridine, and pyridine.

In addition, among the aforementioned chemical structural features, preferred examples of the aromatic ring include benzene, naphthalene, anthracene, biphenyl, triphenyl, and the like.

As an example of an ultraviolet absorber having the above-mentioned chemical structural characteristics, an ultraviolet absorber having a structure of the following formula (1) (see [2,4,6-[2-{4-(octyl- 2-(methyl acetate)oxy-2-hydroxyphenyl}]-1,3,5-tri-(3) ) .

[chemical 1]

The ultraviolet absorber in the present embodiment preferably has an absorption peak in a wavelength range of not less than 250 nm and not more than 400 nm. Thereby, favorable total ablation becomes easy to occur.

In addition, the ultraviolet absorber in this embodiment preferably has an absorbance of light having a wavelength of 355 nm of 0.5 or more, particularly preferably 1.0 or more, and still more preferably 1.2 or more. Thereby, favorable total ablation becomes easy to occur. In addition, the upper limit value of the above-mentioned absorbance is not particularly limited, and may be, for example, 6.0 or less.

In addition, the above-mentioned absorption peak and the above-mentioned absorbance of the ultraviolet absorber can be obtained by preparing an acetonitrile solution with a concentration of 0.01% by mass and using a spectrophotometer ( For example, "UV-3600" manufactured by Shimadzu Corporation) is used for measurement.

(1-2) Photopolymerization initiator The kind of said photopolymerization initiator is not specifically limited. As an example of a preferable photopolymerization initiator, it is preferable to use 2-dimethylamino-2-(4-methylbenzyl)-1-(4-𠰌linyl-phenyl)butane- 1-ketone, ethyl ketone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetyloxime), 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(O-benzoyl oxime), 2-benzyl-2-dimethylamino-1 At least one of -(4-alphalinylphenyl)-butanone and 2-methyl-1-[4-(methylthio)phenyl]-2-alphalinylpropan-1-one.

It is also possible to use other photoinitiators together with the said photoinitiator. Examples of photopolymerization initiators that can be used in combination include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone, dimethylaminobenzene Ethanone, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl Base-1-phenylpropane-1-one, 1-hydroxycyclohexyl phenyl ketone, 4-(2-hydroxyethoxy)phenyl-2-(hydroxy-2-propyl) ketone, 1-[4 -(2-Hydroxyethoxy)-phenyl]-2-hydroxy-methylacetone, benzophenone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone , Dichlorodiphenyl ketone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tertiary-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylanthraquinone Benzyl thioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal , p-dimethylaminobenzoate, oligo[2-hydroxy-2-methyl-1[4-(1-methylvinyl)phenyl]acetone], 2,4,6-trimethyl Benzoyl-diphenyl-phosphine oxide, etc.

It is preferable that the photoinitiator in this embodiment has an absorption peak in the wavelength range of 200 nm or more and 400 nm or less. Thereby, the resin layer 11 absorbs laser light efficiently, and thereby it becomes easy to perform total ablation well. From this point of view, the lower limit of the above range is particularly preferably 300 nm or more, further preferably 330 nm or more. In addition, the upper limit of the above range is particularly preferably 380 nm or less, further preferably 370 nm or less.

In addition, the said absorption peak can be identified based on the following method. First, a photopolymerization initiator is dissolved in methanol or acetonitrile as a solvent to prepare a measurement solution having a concentration of 0.01% by mass. Next, the absorbance of this measurement solution is measured with a spectrophotometer (eg, "UV-3600" manufactured by Shimadzu Corporation) to obtain an absorption spectrum. Then, from the obtained absorption spectrum, the wavelength range of the absorption peak (nm) can be specified.

In addition, the photopolymerization initiator in this embodiment preferably has an absorbance at a wavelength of 355 nm in a solution having a concentration of 0.01% by mass of 0.5 or more, particularly preferably 0.75 or more, and still more preferably 1.0 or more. When the above-mentioned absorbance is 0.5 or more, the resin layer 11 absorbs laser light efficiently, thereby making it easy to perform total ablation well. In addition, the upper limit value of the above-mentioned absorbance is not particularly limited, for example, it may be 4.0 or less.

In addition, the above-mentioned absorbance is obtained by preparing a methanol solution with a photopolymerization initiator concentration of 0.01% by mass (if the photopolymerization initiator is insoluble in methanol, it is an acetonitrile solution) and using ultraviolet-visible light-near infrared rays (UV-Vis-NIR) A spectrophotometer (manufactured by Shimadzu Corporation, product name "UV-3600", optical path length: 10 mm) measures absorbance in the solution in a wavelength range of 200 to 500 nm.

(1-3) Blending amount of laser light absorbing components The workpiece processing sheet 1 of this embodiment preferably satisfies at least one of Condition 1 and Condition 2 related to the compounding amount of the laser light absorbing component, as described above.

That is, when condition 1 is satisfied, the content of the laser light absorbing component in the resin layer 11 is at least 10% by mass, particularly preferably at least 13% by mass, and still more preferably at least 16% by mass. When the content of the laser light absorbing component falls within such a range, the resin layer 11 efficiently absorbs laser light, thereby facilitating good total ablation. Furthermore, the content of the laser light absorbing component is preferably at most 60% by mass, particularly preferably at most 50% by mass, and even more preferably at most 40% by mass. Thereby, it becomes easy to ensure the compounding quantity of the component other than a laser light absorbing component (for example, the adhesive agent mentioned later), and it becomes easy to obtain the workpiece|work processing sheet 1 which has desired performance.

Also, regarding condition 1, when a laser light absorbing component is blended into an adhesive composition described later, the content of the laser light absorbing component in the adhesive composition is equal to the amount of the acrylic polymer (A) described later. 100 parts by mass, preferably at least 12 parts by mass, particularly preferably at least 16 parts by mass, even more preferably at least 20 parts by mass. When the content of the laser light absorbing component falls within such a range, the resin layer 11 efficiently absorbs laser light, thereby facilitating good total ablation. Furthermore, the content of the laser light absorbing component in the adhesive composition is preferably at most 72 parts by mass, particularly preferably at most 60 parts by mass, and still more preferably at most 48 parts by mass, relative to 100 parts by mass of the acrylic polymer (A) described later. Parts by mass or less. Thereby, it becomes easy to ensure the compounding quantity of the component other than a laser light absorbing component (for example, the adhesive agent mentioned later), and it becomes easy to obtain the workpiece|work processing sheet 1 which has desired performance.

And, in the case of satisfying condition 2, in the case where the content of the laser light absorbing component in the resin layer 11 is X mass % and the thickness of the resin layer 11 is Y μm, the value obtained by dividing X by Y ( X/Y) is 2.0 or more, particularly preferably 2.2 or more, and most preferably 2.3 or more. When the above-mentioned value (X/Y) falls within these ranges, the resin layer 11 absorbs the laser light efficiently, thereby facilitating good total ablation. In addition, the above-mentioned value (X/Y) is preferably 60 or less, more preferably 40 or less, particularly preferably 10 or less, and still more preferably 5 or less. Thereby, it becomes easy to ensure the compounding quantity of the component other than a laser light absorbing component (for example, the adhesive agent mentioned later), and it becomes easy to obtain the workpiece|work processing sheet 1 which has desired performance.

(2) Adhesive As mentioned above, the resin layer 11 in this embodiment may also contain an adhesive in addition to the laser light absorbing component. In this case, the resin layer 11 is preferably formed of an adhesive composition containing a laser light absorbing component.

The above-mentioned adhesive is not particularly limited as long as it can exhibit sufficient holding power (adhesive force) to adherends such as workpiece chips. Examples of the adhesive include acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyester adhesives, and polyvinyl ether adhesives. Among them, it is preferable to use an acrylic adhesive from the viewpoint of easily exhibiting a desired adhesive force.

As said acrylic adhesive agent, the acrylic adhesive agent which used an acrylic polymer (A) as a base polymer is mentioned. The weight average molecular weight (Mw) of the acrylic polymer (A) is preferably at least 10,000, particularly preferably at least 100,000. In addition, the weight average molecular weight (Mw) is preferably at most 2 million, particularly preferably at most 1.5 million. When the weight average molecular weight of the acrylic polymer (A) is 10,000 or more, it becomes easy to increase the cohesive force of the obtained adhesive force, and it becomes easy to suppress the adhesive remaining on the separated workpiece pieces. Moreover, it becomes easy to obtain the stable coating film of the resin layer 11 because a weight average molecular weight is 2 million or less. In addition, the weight average molecular weight (Mw) in this specification is the standard polystyrene conversion value measured by the gel permeation chromatography method (GPC method).

In addition, the glass transition temperature (Tg) of the acrylic polymer (A) is preferably -70°C or higher, particularly preferably -60°C or higher. In addition, the glass transition temperature (Tg) is preferably 20°C or lower, particularly preferably 10°C or lower. When the glass transition temperature (Tg) of an acryl-type polymer (A) is the said range, it becomes easy to achieve desired cohesive force, and simultaneously realizes desired adhesive force.

The above-mentioned acrylic polymer (A) preferably contains at least a (meth)acrylate monomer as a constituent monomer, and preferably has a functional group capable of reacting with a crosslinking agent (B) described later. Functional group (hereinafter also referred to as "reactive functional group").

As the (meth)acrylate monomer, specifically, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, ( Amyl methacrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, (meth)acrylate Base) Alkyl (meth)acrylates with an alkyl group of 1 to 18 carbon atoms such as isononyl acrylate, decyl (meth)acrylate, and lauryl (meth)acrylate; cycloalkyl groups with a carbon number of 1 to 18 Cycloalkyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, (meth)acrylic acid esters such as dicyclopentenyloxyethyl (meth)acrylic acid imide ester and other (meth)acrylic acid esters with a ring skeleton; (meth)hydroxymethyl acrylate, (meth) Hydroxyl-containing (meth)acrylates such as 2-hydroxyethyl acrylate and 2-hydroxypropyl (meth)acrylate; glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate Epoxy group-containing (meth)acrylates such as (3,4-epoxycyclohexyl)methyl (meth)acrylate, 3-epoxycyclo-2-hydroxypropyl (meth)acrylate, etc.

Further, monomers other than (meth)acrylate monomers such as acrylic acid, methacrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide may be copolymerized. These may be used individually by 1 type, and may use 2 or more types together.

The acrylic polymer (A) contains a reactive functional group and reacts with a functional group of a crosslinking agent (B) described later to form a three-dimensional network structure, thereby improving the cohesiveness of the resin layer 11 easily. Examples of reactive functional groups of the acrylic polymer (A) include carboxyl groups, amino groups, epoxy groups, and hydroxyl groups. Since it reacts with a valent isocyanate compound, it is preferable to contain a hydroxyl group.

The acrylic polymer (A) is formed by using the above-mentioned hydroxyl group-containing (meth)acrylate and a monomer having a reactive functional group such as acrylic acid, whereby the reactive functional group can be introduced into the acrylic polymer (A).

The proportion of monomers having reactive functional groups (hereinafter also referred to as monomers containing reactive groups) to all monomers constituting the acrylic polymer (A) is preferably at least 0.3% by mass, particularly preferably 0.5% by mass %above. In addition, the above ratio is preferably at most 40% by mass, particularly preferably at most 20% by mass. By including the reactive group-containing monomer in this range, it becomes easy to achieve desired cohesive force and simultaneously realize desired adhesive force.

In addition, the acrylic polymer (A) preferably contains the above-mentioned alkyl (meth)acrylate as a constituent monomer, more preferably an alkyl (meth)acrylate containing an alkyl group and having 1 to 10 carbon atoms. , particularly preferably an alkyl (meth)acrylate having an alkyl group and having 4 to 8 carbon atoms. When the acrylic polymer (A) contains the above-mentioned alkyl (meth)acrylate, the ratio of the alkyl (meth)acrylate to all monomers constituting the acrylic polymer (A) is preferably 30% by mass or more , especially preferably 35% by mass or more. In addition, the above ratio is preferably at most 99% by mass, particularly preferably at most 95% by mass. By containing the alkyl (meth)acrylate in this range, it becomes easy to achieve desired cohesive force and simultaneously realize desired adhesive force.

From the viewpoint of easily adjusting the storage modulus of the resin layer 11 to a desired range, it is preferable to use a crosslinking agent (B). As the crosslinking agent (B), a polyfunctional compound having reactivity with a reactive functional group contained in the acrylic polymer (A) or the like can be used. Examples of such polyfunctional compounds include isocyanate compounds, epoxy compounds, amine compounds, melamine compounds, acridine compounds, hydrazine compounds, aldehyde compounds, oxazoline compounds, metal alkoxide compounds, and metal chelate compounds. , metal salts, ammonium salts, reactive phenolic resins, etc.

The blending amount of the crosslinking agent (B) is preferably at least 0.001 parts by mass, particularly preferably at least 0.1 parts by mass, and still more preferably at least 0.2 parts by mass, based on 100 parts by mass of the acrylic polymer (A). Furthermore, the blending amount of the crosslinking agent (B) is preferably at most 20 parts by mass, particularly preferably at most 10 parts by mass, and still more preferably at most 5 parts by mass, based on 100 parts by mass of the acrylic polymer (A).

In addition, the adhesive constituting the resin layer 11 may be an active energy ray curable adhesive. As such an active energy ray-curing adhesive, known ones can be used, for example, those disclosed in International Publication No. 2018/084021 can be used.

In the adhesive composition for forming the resin layer 11, other additives may be added in addition to the above-mentioned components. Examples of such additives include coloring materials such as tackifiers, dyes, and pigments, flame retardants, fillers, and antistatic agents. Moreover, it is preferable that this adhesive composition does not contain a gas generating agent from a viewpoint of easy to generate|occur|produce separation of a workpiece|work piece well. If a gas generating agent is used, gas may be generated in the entire area of the resin layer 11 . In this case, total ablation occurs only at a desired position, and it becomes difficult to separate only the workpiece small pieces located there, and it may become difficult to perform good separation of the workpiece small pieces.

(3) The thickness of the resin layer The thickness of the resin layer 11 in this embodiment is preferably at least 1 μm, particularly preferably at least 2 μm, and even more preferably at least 3 μm. When the thickness of the resin layer 11 is 1 μm or more, favorable total ablation is likely to occur. In addition, the thickness of the resin layer 11 is preferably 60 μm or less, particularly preferably 40 μm or less, further preferably 20 μm or less. When the thickness of the resin layer 11 is 60 micrometers or less, it becomes easy to satisfy the said condition 2.

2. Substrate The base material 12 in this embodiment is not particularly limited in terms of its composition, physical properties, and the like. It is preferable that the base material 12 is comprised by resin from a viewpoint that the workpiece|work processing sheet 1 exhibits a desired function easily. When the substrate 12 is made of resin, examples of the resin include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate ) and other polyester-based resins; polyolefin-based resins such as polyethylene, polypropylene, polybutene, polybutadiene, polymethylpentene, ethylene-norbornene copolymer, and norbornene resin; ethylene-vinyl acetate Ester copolymers; ethylene-(meth)acrylic acid copolymers, ethylene-(meth)acrylate copolymers, other ethylene-(meth)acrylate copolymers and other ethylene-based copolymer resins; polyvinyl chloride, vinyl chloride Polyvinyl chloride-based resins such as copolymers; (meth)acrylate copolymers; polyurethanes; polyimides; polystyrene; polycarbonate; fluororesins, etc. In addition, the resin constituting the base material 12 may be cross-linked with the above-mentioned resin, modified by ion polymer or the like of the above-mentioned resin, or the like. In addition, the base material 12 may be a single-layer film made of the above-mentioned resin, or may be a laminated film in which a plurality of such films are laminated. In this laminated film, the materials constituting each layer may be of the same type or different types.

The surface of the substrate 12 in this embodiment may be subjected to surface treatment by oxidation, roughening, or primer treatment for the purpose of improving adhesion to the resin layer 11 . Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet method), flame treatment, hot air treatment, ozone, ultraviolet irradiation treatment, etc., and examples of the roughening method include sandblasting. method, thermal spray treatment, etc.

The base material 12 in this embodiment may contain various additives such as colorants, flame retardants, plasticizers, antistatic agents, lubricants, and fillers. Also, when the resin layer 11 includes a material cured by active energy rays, the base material 12 preferably has penetrability to the active energy rays.

The manufacturing method of the base material 12 in this embodiment is not specifically limited as long as the base material 12 is manufactured from resin. For example, the resin can be formed into a sheet by melt extrusion methods such as T-die (T-DIE) method and circular die method; calender method; solution method such as dry method and wet method, etc., thereby And manufacture.

The thickness of the base material 12 in this embodiment is preferably at least 10 μm, particularly preferably at least 30 μm, and even more preferably at least 50 μm. In addition, the thickness of the substrate 12 is preferably less than 500 μm, more preferably less than 300 μm, particularly preferably less than 200 μm, further preferably less than 150 μm, most preferably less than 100 μm. When the thickness of the base material 12 is in the above-mentioned range, the workpiece processing sheet 1 has rigidity and flexibility with a predetermined balance, and it becomes easy to handle the workpiece small pieces well.

3. Peeling sheet In the present embodiment, when the resin layer 11 contains an adhesive as one of its constituent components, it protects the workpiece chip until it is attached to the surface on the opposite side of the base material 12 in the resin layer 11. For the purpose, there can be a release sheet on the layer.

The structure of the said peeling sheet is arbitrary, and what peels the plastic film with a peeling agent etc. is mentioned as an example. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. . As the above-mentioned release agent, polysiloxane-based, fluorine-based, long-chain alkyl-based, etc. can be used, and among them, polysiloxane-based, which is inexpensive and can obtain stable performance, is preferable.

The thickness of the release sheet is not particularly limited, and may be, for example, not less than 20 μm and not more than 250 μm.

4. Other components In the workpiece processing sheet 1 of this embodiment, an adhesive layer may be formed on the surface of the resin layer 11 opposite to the substrate 12 . In this sheet, by attaching a workpiece to the surface opposite to the resin layer 11 in the adhesive layer, and cutting the workpiece together with the adhesive layer, a single-layered adhesive can be obtained. A small piece of workpiece in layers. The chip can easily fix the object on which the workpiece chip is mounted by the singulated adhesive layer. As the material constituting the above-mentioned adhesive layer, those containing thermoplastic resin and low molecular weight thermosetting adhesive components, those containing B-stage (semi-hardened) thermosetting adhesive components, etc. are preferably used.

Furthermore, in the workpiece processing sheet 1 of the present embodiment, a protective film forming layer may be formed on the surface of the resin layer 11 opposite to the substrate 12 . In such a sheet, by attaching a workpiece to the surface on the opposite side of the resin layer 11 in the protective film forming layer, and cutting the workpiece together with the protective film forming layer, a monolithic laminate can be obtained. The workpiece small piece of the protective film forming layer. As the workpiece, it is preferable to use one on which a circuit is formed on one side. In this case, a protective film forming layer is usually formed on the surface opposite to the surface on which the circuit is formed. The monomeric protective film forming layer can form a protective film with sufficient durability on a small workpiece by curing it at a predetermined time point. The protective film forming layer is preferably composed of an uncured curable adhesive.

5. Manufacturing method of workpiece handling sheet The manufacturing method of the workpiece processing sheet 1 of this embodiment is not particularly limited. For example, the resin layer 11 may be directly formed on the base material 12 , or the resin layer 11 may be transferred onto the base material 12 after forming the resin layer 11 on a process sheet.

When the resin layer 11 contains an adhesive as one of its constituent components, the resin layer 11 can be formed by a known method. For example, an adhesive composition for forming the resin layer 11, and a coating solution further containing a solvent or a dispersion vehicle as desired are prepared. Then, the above-mentioned coating liquid is applied to one side of the base material or the side having releasability of the release sheet (hereinafter, may be referred to as a “releasable surface”). Next, the resin layer 11 can be formed by drying the obtained coating film.

The coating of the above-mentioned coating liquid can be carried out by a known method, for example, by bar coating method, knife coating (knife coating) method, roll coating method, knife coating (blade coating) method, die coating method, gravure coating method etc. In addition, the characteristics of the coating liquid are not particularly limited as long as it can be applied, and the components for forming the resin layer 11 may be contained as solutes or dispersoids. In addition, when the resin layer 11 is already formed on the release sheet, the release sheet can be peeled off as a process material, and the resin layer 11 can be protected until it is attached to an adherend.

In the case where the adhesive composition for forming the resin layer 11 contains the aforementioned crosslinking agent, it is preferable to make the coating by changing the above-mentioned drying conditions (temperature, time, etc.) or by additionally setting heat treatment. The crosslinking reaction between the polymer component in the film and the crosslinking agent proceeds, and a crosslinked structure is formed in the resin layer 11 at a desired density. Moreover, in order to make the above-mentioned cross-linking reaction fully proceed, after the workpiece processing sheet 1 is completed, it can also be aged for several days at 23° C. and a relative humidity of 50% for several days.

6. How to use the workpiece processing sheet The workpiece processing sheet 1 of this embodiment can be preferably used for processing small workpieces. As mentioned above, in the workpiece processing sheet 1 of this embodiment, since the resin layer 11 is irradiated with laser light, it can be completely ablated efficiently, so the workpiece held on the resin layer 11 can be accurately removed. Small pieces are separated towards the specified position.

As an example of the usage method of the workpiece processing sheet 1 of this embodiment, the following usage method can be mentioned: the resin layer 11 is selectively separated from the resin layer 11 and held in the resin layer 11 by total ablation locally occurring in the resin layer 11. Any one of the plurality of workpiece small pieces on the surface opposite to the substrate 12.

In the above method of use, the plurality of workpiece pieces held on the resin layer 11 can be obtained by placing the workpieces held on the surface of the resin layer 11 opposite to the base material 12 (the material to be the workpiece pieces) on the surface. Those obtained by monomerization above. That is, the workpiece chip may be one obtained by cutting a workpiece on the resin layer 11 . Alternatively, the workpiece small piece may be formed independently of the workpiece processing sheet 1 of the present embodiment and placed on the resin layer 11 .

In addition, in the case where the workpiece processing sheet 1 of the present embodiment includes the aforementioned adhesive layer, protective film forming layer, and the like, it is preferable to cut these layers and the workpiece on the resin layer 11 . Thereby, a workpiece small piece in which these layers are laminated can be obtained.

The shape and size of the workpiece chip in this embodiment are not particularly limited, but the size of the workpiece chip is preferably 10 μm ² or more in plan view, particularly preferably 100 μm ² or more. In addition, the area of the small workpiece is preferably 1 mm ² or less, particularly preferably 0.25 mm ² or less in plan view. Furthermore, as the size of the workpiece piece, when the workpiece piece is rectangular, the smallest side of the workpiece piece is preferably 2 μm or more, particularly preferably 5 μm or more, and still more preferably 10 μm or more. In addition, the above-mentioned smallest side is preferably 1 mm or less, particularly preferably 0.5 mm or less. Specific examples of the size of the rectangular workpiece piece include 2 μm×5 μm, 10 μm×10 μm, 0.5 mm×0.5 mm, 1 mm×1 mm, and the like. The workpiece processing chip 1 of this embodiment can handle even such fine workpiece pieces, especially fine workpiece pieces that are difficult to be separated from the chip by upward pushing of the needles, and can be processed well. On the other hand, the workpiece processing sheet 1 of the present embodiment can also be used for large-sized workpiece chips with an area larger than 1 mm ² (for example, 1 mm ² to 2000 mm ² ) and a thickness of 1 to 10000 μm (for example, 10 to 1000 μm). Handle well.

Examples of workpiece small pieces include semiconductor elements, semiconductor devices, and more specifically, micro light emitting diodes, power elements, MEMS (Micro Electro Mechanical Systems, micro-electromechanical systems), and the like. Among them, the workpiece chip is preferably a light-emitting diode, particularly preferably a light-emitting diode selected from submillimeter light-emitting diodes and micro light-emitting diodes. In recent years, the development of devices that arrange sub-millimeter light-emitting diodes and micro-light-emitting diodes at a high density is being studied, and the workpiece processing sheet 1 of this embodiment that can process these light-emitting diodes with high precision is very suitable for the manufacture of such devices.

Hereinafter, a device manufacturing method will be described based on FIG. 2 as a specific usage example of the workpiece processing sheet 1 . The manufacturing method of the device has at least the following three steps: preparation step (Fig. 2(a)), configuration step (Fig. 2(b)) and separation step (Fig. 2(c) and (d)).

In the preparatory step, as shown in FIG. 2( a ), a laminate in which a plurality of workpiece small pieces 2 are held on the surface of the workpiece processing sheet 1 of the present embodiment on the resin layer 11 side is prepared. This laminated body can be prepared by placing a separately produced workpiece chip 2 on the workpiece handling sheet 1, or by singulating the workpiece held on the surface of the resin layer 11 side on the surface. (i.e. cutting) and prepare. This cutting can be performed by known methods.

The shape and size of the small workpiece 2 are not particularly limited as mentioned above, and the preferred size is also as mentioned above. Specific examples of the workpiece chip 2 are, as mentioned above, semiconductor elements, semiconductor devices, etc., particularly light emitting diodes such as submillimeter light emitting diodes and micro light emitting diodes.

In the next arranging step, as shown in FIG. 2( b ), the laminated body is arranged so as to face the surface of the laminated body on the workpiece small piece 2 side with respect to the object 3 capable of accommodating the workpiece small piece 2 . The example of the object 3 is appropriately determined according to the device for manufacturing, but in the case where the workpiece chip 2 is a light-emitting diode, specific examples of the object 3 include substrates, sheets, reels, etc., and are particularly suitable for use. Wiring substrate with wiring.

After that, in the separation step, first, as shown in FIG. 2( c ), laser light is irradiated to the position where at least one workpiece small piece 2 is attached in the resin layer 11 of the laminated body. The irradiation may be performed simultaneously to a plurality of positions where the workpiece small pieces 2 are attached, or sequentially to the positions. Irradiation conditions of laser light are not limited as long as total ablation can occur. As a device for irradiation, those known in the art can be used.

By the above irradiation, as shown in FIG. 2( d ), total ablation can occur at the irradiated position in the resin layer 11 . Specifically, by irradiation of laser light, the components constituting the resin layer 11 evaporate or volatilize, and the resin layer 11 in the irradiated position disappears. Thereby, the workpiece holding piece 2 on the workpiece handling piece 1 side disappears and falls toward the object 3 . As a result, the workpiece small piece 2' existing at the position where the total ablation has occurred can be placed on the object 3.

In addition, when the resin layer 11 in this embodiment is an adhesive layer composed of the above-mentioned active energy ray-curable adhesive, the above-mentioned device manufacturing method may further include the following curing step. That is, it may be possible to provide the entire resin layer 11 in the laminated body in which a plurality of workpiece pieces 2 are held on the surface of the resin layer 11 side, or affixed to the resin layer 11 in the above-mentioned laminated body. A hardening step in which the resin layer 11 is wholly or locally hardened by irradiating active energy rays to at least one position of the workpiece small piece 2 . This hardening step can be performed before, or simultaneously with, the separation step described above.

Irradiation of active energy rays in the hardening step can be performed using known methods. For example, as a light source, a high-pressure mercury lamp, an ultraviolet irradiation device equipped with an ultraviolet LED, or a laser light irradiation device used in the separation step can be used. In the case where the hardening step and the separation step are performed simultaneously, it is preferable to perform irradiation with laser light 4 using a laser light irradiation device, and make it also serve as irradiation of active energy rays.

The above-mentioned device manufacturing method may include steps other than the preparation step, arrangement step, hardening step, and separation step. For example, grinding, die bonding, wire bonding, molding, inspection, transfer steps, etc. may be performed at any point in time between the preparation step and the separation step.

According to the device manufacturing method described above, various devices can be manufactured by appropriately selecting the workpiece chip 2, the object 3, and the like to be used. For example, in the case of using a light-emitting diode selected from submillimeter light-emitting diodes and micro-light-emitting diodes as the workpiece chip 2, a light-emitting device with a plurality of such light-emitting diodes can be manufactured, more specifically , to manufacture displays. In particular, displays with micro light-emitting diodes as pixels, displays with multiple submillimeter light-emitting diodes as backlights, etc. can be manufactured.

Furthermore, the workpiece processing sheet 1 of this embodiment can also be used in a method of selectively removing a specified workpiece small piece 2 among a plurality of workpiece small pieces 2 provided on the sheet.

For example, after a plurality of light emitting diodes and the like have been produced on the workpiece processing sheet 1 of this embodiment, inspection of the light emitting diodes is performed on the sheet. Therefore, only the light-emitting diodes that have been confirmed as defective products can be completely ablated and removed from the workpiece processing sheet 1 .

Furthermore, it is also possible to transfer the collection of these good products from the workpiece processing sheet 1 to the shipping sheet. At this time, in the case where the resin layer 11 is composed of the aforementioned active energy ray-curable adhesive, the adhesive force of the light-emitting diode to the workpiece processing sheet 1 can be improved by irradiating the resin layer 11 with active energy rays. It is possible to transfer the set of good products to the shipping sheet well. Afterwards, another good product is arranged at the position where the defective product has been removed, so that a workpiece processing sheet 1 with only good products can be obtained.

In the method of removing defective products by total ablation as described above, since there is no need to expand the chip and pick up defective products, it is difficult to change the spacing of the light emitting diodes, shift the position, and the like. Therefore, it becomes easy to transfer to a shipment-use sheet in good condition.

The embodiments described above are described in order to facilitate understanding of the present invention, and are not described in order to limit the present invention. Therefore, the gist of each element disclosed in the above embodiments also includes all design changes, equivalents, and the like within the technical scope of the present invention.

For example, another layer may be laminated between the resin layer 11 and the base material 12 in the workpiece processing sheet 1 of this embodiment, or on the surface of the base material 12 opposite to the resin layer 11 . An adhesive layer is mentioned as a specific example of this other layer. In this case, the above-mentioned separation step and the like can be performed in a state where the surface on the side of the adhesive layer is attached to the support (transparent substrate such as a glass plate).

The adhesive constituting the adhesive layer is not particularly limited, but is preferably one that hardly absorbs active energy rays and blocks active energy rays. In this case, in the case of irradiating laser light that penetrates the adhesive layer, the laser light becomes easy to reach the resin layer 11, and good total ablation becomes easy to occur. Specifically, as the adhesive constituting the above-mentioned adhesive layer, it is preferable to use an adhesive that does not have active energy ray curability, and it is particularly preferable to use an adhesive that does not contain an active energy ray curable component. By using an adhesive that does not have active energy ray curability, the adhesive layer does not harden even when the laser light is irradiated, thereby preventing the workpiece processing sheet 1 from being unintentionally peeled off from the transparent substrate. The thickness of the adhesive layer is not particularly limited, but is preferably, for example, 5 to 50 μm. [Example]

Hereinafter, although an Example etc. demonstrate this invention more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1] (1) Preparation of adhesive composition By the solution polymerization method, 70 parts by mass of 2-ethylhexyl acrylate and 30 parts by mass of 2-hydroxyethyl acrylate were polymerized to obtain an acrylic polymer. When the weight average molecular weight (Mw) of this acrylic polymer was measured by the method mentioned later, it was 800,000.

100 parts by mass of the above-obtained acrylic polymer (in terms of solid content, the same applies hereinafter) and trimethylolpropane-modified methylene diisocyanate (manufactured by Tosoh Corporation, trade name "CORONATE") as a crosslinking agent were mixed in a solvent. L") 1.5 parts by mass, and ginseng [2,4,6-[2-{4-(octyl-2-methyl acetate)oxy-2-hydroxyphenyl}]-1 as a laser light absorbing component , 3,5-Trisin (a hydroxyphenyltrisin series ultraviolet absorber, manufactured by BASF, product name "Tinuvin 477") 5 parts by mass to obtain a coating liquid of an adhesive composition.

(2) Production of workpiece processing sheet For the easy-adhesive surface of a polyethylene terephthalate film (manufactured by Toyobo, product name "COSMOSHINE A4100", thickness: 50μm) that has been subjected to easy-adhesive treatment on one side as the base material, the coating is performed by the above steps ( 1) The obtained coating liquid of the adhesive composition is dried by heating the obtained coating film. Thereby, a resin layer (adhesive layer) with a thickness of 2 μm was formed on the substrate.

Next, a release sheet (LINTEC Co. Made, product name "SP-PET381031") to the peeling side for lamination. Thereby, the workpiece|work processing sheet which laminated|stacked the peeling sheet, the resin layer, and a base material sequentially was obtained.

In addition, when the content of the laser light absorbing component in the formed resin layer was calculated, it was 4.69% by mass. In addition, when calculating the value of dividing X by Y (X/Y) in the case where the content of the laser light absorbing component in the resin layer is X mass % and the thickness of the resin layer is Y μm for this example, , it is 2.35.

(3) Measurement method of weight average molecular weight The aforementioned weight average molecular weight (Mw) is a standard polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography (GPC) under the following conditions (GPC measurement). ＜Measurement conditions＞ ・Measuring device: Tosoh Co., Ltd., HLC-8320 ・GPC column (pass through in the following order): Tosoh Co., Ltd. TSK gel superH－H TSK gel superHM－H TSK gel superH2000 ・Measurement solvent: Tetrahydrofuran ・Measurement temperature: 40°C

[Examples 2-3 and Comparative Examples 1-2] A workpiece processing sheet was produced in the same manner as in Example 1 except that the content of the crosslinking agent, the content of the laser light absorbing component, and the thickness of the resin layer were changed as shown in Table 1. In addition, Comparative Example 1 is an example in which no laser light absorbing component is used.

In addition, in Table 1, for Examples 2-3 and Comparative Examples 1-2, the content (mass %) of the laser light-absorbing component in the resin layer and the content of the laser light-absorbing component in the resin layer are also shown. It is a value (X/Y) obtained by dividing X by Y when X mass % is assumed and the thickness of the resin layer is Y μm.

[Test example] (Evaluation of laser peeling suitability) (1) Preparation of wafer on workpiece handling sheet (preparation step) Attach a dicing sheet (manufactured by Lintec Co., Ltd., product name "D-485H") on the adhesive side. Next, a ring frame for dicing was attached to the peripheral portion (position not overlapping the silicon wafer) of the above-mentioned adhesive surface in the dicing sheet. Furthermore, the cutting pieces are cut according to the outer diameter of the ring. Thereafter, the silicon wafer was diced into wafers having a size of 300 μm×300 μm using a dicing device (manufactured by DISCO, product name “DFD6362”). Thereafter, the diced sheet was irradiated with ultraviolet rays (illuminance: 230 mW/cm ² , light intensity: 190 mJ/cm ² ). Thereby, a laminated body in which a plurality of wafers are provided on a dicing sheet is obtained.

Next, the peeling sheet was peeled off from the workpiece handling sheet manufactured by the Example and the comparative example, and the exposed surface exposed by this was bonded to the surface where many wafers existed in the laminated body obtained above. Thereafter, the diced sheets are peeled off from the plurality of wafers. Thereby, a plurality of wafers are transferred from the dicing sheet to the workpiece processing sheet, and a laminate in which a plurality of wafers are provided on the workpiece processing sheet is obtained.

(2) Separation of wafers by laser light irradiation (separation step) For the laminate obtained in the above step (1) with a plurality of wafers on the workpiece handling sheet, a laser light irradiation device is used to irradiate each wafer with laser light passing through the workpiece handling sheet.

Specifically, using a laser light irradiation device (manufactured by KEYENCE, product name "MD-U1000C"), the wafer was irradiated with laser light having a wavelength of 355 nm so as to pass through the workpiece processing wafer. This irradiation is carried out so that the laser spot is scanned from the outer periphery of the wafer toward the center in a swirl shape, and the entire surface of the wafer is irradiated. At this time, the diameter of the laser light spot is 20 μm, the frequency: 40 kHz, the scanning speed: 500 mm/s, and the irradiation amount: 50 μJ/shot. Then, 100 wafers (a cluster of 10 vertically × 10 horizontally wafers) are selected from among the plurality of wafers, and irradiated.

(3) Confirmation of the disappearance of the resin layer and the separation of the wafer With regard to the positions subjected to the above irradiation, the presence or absence of disappearance of the resin layer was confirmed using a laser microscope. Then, on the basis of the following criteria, evaluation was performed on the disappearance of the resin layer. The results are shown in Table 1. ○...disappeared sufficiently in all positions. ×... There are places where the disappearance is insufficient.

In addition, based on the following criteria, the presence or absence of detachment of the wafer from the workpiece processing sheet was confirmed, and the laser peeling suitability was evaluated. The results are shown in Table 1. ○... All 100 wafers were detached. ×...The number of wafers where detachment occurred was less than 100 pieces.

[Table 1] Content of crosslinking agent (relative to the amount of 100 parts by mass of acrylic polymer) (parts by mass) Content of laser light absorbing components Thickness of resin layer (μm) (Y) X/Y Disappearance of the resin layer Laser peeling suitability Amount relative to 100 parts by mass of acrylic polymer (parts by mass) Amount in resin layer (mass%) (X) Example 1 1.5 5 4.69 2 2.35 ○ ○ Example 2 1.5 10 8.97 2 4.48 ○ ○ Example 3 3.0 20 16.26 4 4.07 ○ ○ Comparative example 1 1.5 - - 1 - x x Comparative example 2 1.5 1 0.98 10 0.10 x x

As can be seen from Table 1, the workpiece processing sheets manufactured in the examples have excellent laser stripping properties. [Industrial Utilization]

The workpiece processing sheet of the present invention can be suitably used in the manufacture of displays and the like having micro light emitting diodes as pixels.

1: Workpiece handling sheet 11: resin layer 12: Substrate 2,2': small piece of workpiece 3: object 4: laser light

Fig. 1 is a cross-sectional view of a workpiece processing sheet according to an embodiment of the present invention. Fig. 2 is a cross-sectional view illustrating a method of manufacturing a device using a workpiece processing sheet according to an embodiment of the present invention.

1: Workpiece handling sheet

11: resin layer

12: Substrate

Claims (19)

A workpiece processing sheet, which is a workpiece processing sheet having a base material and a resin layer, the resin layer is laminated on one side of the base material and can hold a small workpiece, and is characterized in that: The aforementioned resin layer contains at least 10% by mass of a laser light absorbing component that absorbs the wavelength of laser light, The aforementioned resin layer is completely ablated by the irradiation of the aforementioned laser light. A workpiece processing sheet, which is a workpiece processing sheet comprising a base material and a resin layer, wherein the resin layer is laminated on one side of the base material and can hold a small piece of workpiece, and is characterized in that: The aforementioned resin layer contains a laser light absorbing component that absorbs the wavelength of laser light, When the content of the laser light absorbing component in the resin layer is X mass % and the thickness of the resin layer is Y μm, the value (X/Y) of dividing X by Y is 2.0 or more. The workpiece processing sheet according to claim 1 or 2, wherein the laser light absorbing component is at least one of an ultraviolet absorber and a photopolymerization initiator. The workpiece treatment sheet according to claim 3, wherein the ultraviolet absorber is an organic compound. The workpiece treatment sheet according to claim 3, wherein the ultraviolet absorber is a compound having one or more heterocycles. The workpiece processing sheet according to claim 3, wherein the ultraviolet absorber has at least one of a carbocyclic ring and a heterocyclic ring, All of the aforementioned carbocyclic rings and the aforementioned heterocyclic rings contained in the aforementioned ultraviolet absorber are monocyclic rings, respectively. The workpiece treatment sheet according to claim 3, wherein the ultraviolet absorber is a compound having a plurality of aromatic rings. The workpiece processing sheet according to claim 1 or 2, wherein the resin layer is an adhesive layer. The workpiece processing sheet according to claim 8, wherein the adhesive constituting the adhesive layer is an acrylic adhesive. The workpiece processing sheet according to claim 1 or 2, wherein the laser light has a wavelength in the ultraviolet region. The workpiece processing sheet according to claim 1 or 2, which is opposite to the base material held in the resin layer for selectively separating from the resin layer by total ablation locally occurring in the resin layer Any one of the plurality of workpiece small pieces on the surface of the surface is used. The workpiece processing sheet according to claim 11, wherein the workpiece small piece is obtained by singulating the workpiece held on the surface of the resin layer opposite to the base material on the surface. The workpiece processing chip according to claim 11, wherein the workpiece chip is at least one selected from semiconductor elements and semiconductor devices. The workpiece processing sheet according to claim 11, wherein the aforementioned small workpiece is a light-emitting diode selected from submillimeter light-emitting diodes and micro-light-emitting diodes. A method for manufacturing a device, characterized in that: A preparatory step, which prepares a laminate, wherein the laminate system is formed by holding a plurality of workpiece small pieces on the surface of the resin layer side in the workpiece processing sheet as described in claim 1 or 2; an arranging step of arranging the laminate so as to face the surface of the laminate on the workpiece small side with respect to the object capable of containing the workpiece; and A separation step of irradiating laser light to the position of the aforementioned resin layer in the aforementioned laminated body where at least one of the aforementioned workpiece small pieces is attached, and total ablation occurs at the aforementioned irradiated position of the aforementioned resin layer, whereby the aforementioned The workpiece processing piece separates the workpiece small piece present at the position where the total ablation occurs, and places the workpiece small piece on the object. The device manufacturing method according to claim 15, wherein, in the preparatory step, the workpiece held on the surface of the resin layer opposite to the base material is singulated on the surface, thereby obtaining The foregoing workpiece small pieces. The device manufacturing method according to claim 15, wherein the workpiece chip is at least one selected from a semiconductor element and a semiconductor device. The device manufacturing method according to claim 15, wherein a light-emitting diode selected from sub-millimeter light-emitting diodes and micro-light-emitting diodes is used as the aforementioned workpiece chip, and a light emitting diode having a plurality of the aforementioned light-emitting diodes is produced. device. The device manufacturing method according to claim 18, wherein the light-emitting device is a display.

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