TW202239036A - Workpiece handling sheet and device manufacturing method - Google Patents

Abstract

Provided is a workpiece handling sheet 1 comprising: a substrate 11; and an boundary surface ablation layer 12 which is laminated on one surface of the substrate 11 and which can hold small workpieces and perform boundary surface ablation by irradiation with a laser beam, wherein the boundary surface ablation layer 12 contains a photoinitiator, and the workpiece handling sheet has a 355 nm wavelength light ray absorbance of 1.5 or more. 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 chip that can be used to manipulate semiconductor components, semiconductor devices, etc. A workpiece processing chip for small workpieces such as micro light emitting diodes, power devices, and MEMS (Micro Electro Mechanical Systems), and a device manufacturing method using the workpiece processing chip.

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

During the above-mentioned assembly, the plurality of micro light-emitting diodes arranged on the supply substrate must be accurately placed on a specific position of the wiring substrate. In this case, a specific one must be selected from among a plurality of micro light emitting diodes and placed on the wiring board, and the plurality of micro light emitting diodes must be placed at the same time.

Irradiation with laser light has been studied from the viewpoint of performing such assembly satisfactorily. For example, after a plurality of micro light-emitting diodes are maintained on a support body through a specific layer, by irradiating the layer with laser light, the ablation of the layer occurs at the irradiated position, whereby the Research has been conducted on a method of placing micro-light emitting diodes that are separated (laser lift-off) on a wiring board (Patent Document 1). Since laser light has good directivity and convergence, it is easy to control the position of irradiation, and it can perform selective placement well. [Prior Art Literature] [Patent Document]

Patent Document 1: Japanese Patent No. 6546278

[Problem to be solved by the invention]

However, as micro-light emitting diodes are further miniaturized and micro-light-emitting diodes are assembled at a higher density, in response to these, more efficient operations are sought compared to conventional means such as Patent Document 1. It is a means of many tiny workpiece pieces such as micro light emitting diodes.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a workpiece processing sheet that can handle well even a small workpiece, and a device manufacturing method using the workpiece processing sheet. [means used to solve a problem]

In order to achieve the above object, firstly, the present invention provides a workpiece processing sheet, which includes: a base material, and a small piece laminated on one side of the base material, which can be used to maintain the workpiece, and the interface is ablated by irradiation of laser light The interface ablation layer contains a photopolymerization initiator, and the absorbance of light with a wavelength of 355 nm of the workpiece treatment sheet is 1.5 or more (Invention 1).

In the workpiece processing sheet related to the above invention (Invention 1), the interface ablation layer contains a photopolymerization initiator, the absorbance of light with a wavelength of 355 nm is within the above range, and the interface ablation is effectively performed when irradiated with laser light. The workpiece small pieces are well separated toward the object.

In the above invention (Invention 1), it is preferable that the photopolymerization initiator has an absorption peak in a wavelength range of not less than 200 nm and not more than 400 nm (Invention 2).

In the above inventions (Inventions 1 and 2), it is preferable to use the interface ablation layer as an adhesive layer (Invention 3).

In the above invention (Invention 3), it is preferable that the adhesive constituting the adhesive layer is an active energy ray-curable adhesive (Invention 4).

In the above inventions (Inventions 3 and 4), it is preferable that the adhesive constituting the adhesive layer is an acrylic adhesive (Invention 5).

In the above inventions (Inventions 1 to 5), it is preferable that the laser light has a wavelength in the ultraviolet range (Invention 6).

In the above inventions (Inventions 1 to 6), when the interface ablation layer causes interface ablation, it is preferable to form a blister at the position where the interface ablation occurs (Invention 7).

In the above-mentioned inventions (Inventions 1 to 7), the surface of the interface ablation layer opposite to the substrate is maintained by locally causing interface ablation in the interface ablation layer to be used. It is preferable that arbitrary workpiece small pieces among the plurality of workpiece small pieces are selectively separated from the above-mentioned interface ablation layer (Invention 8).

In the above invention (Invention 8), it is preferable that the workpiece small pieces are to be maintained on the surface of the above-mentioned interface ablation layer opposite to the base material, and the pieces can be obtained on this surface (Invention 9 ).

In the above inventions (Inventions 8 and 9), it is preferable that the workpiece chip is at least one selected from a semiconductor package and a semiconductor device (Invention 10).

In the above inventions (Inventions 8-10), the workpiece chip is preferably a light-emitting diode selected from miniature light-emitting diodes and micro-light-emitting diodes (invention 11).

Second, the present invention provides a device manufacturing method comprising: preparing a base material, and an interface ablation layer containing a photopolymerization initiator laminated on one side of the base material, and having an absorbance of 1.5 for light with a wavelength of 355 nm. In the above workpiece processing sheet, a preparation step of a laminate formed by maintaining a plurality of workpiece small pieces on the surface of the above-mentioned interface ablation layer side; A method of arranging the layered body on the surface of the workpiece small piece side; a step of arranging the above-mentioned laminated body; for the position where at least one of the above-mentioned workpiece small pieces is attached in the above-mentioned interface ablation layer in the above-mentioned laminated body, laser light is irradiated, and the above-mentioned interface is The interface ablation that occurs at the above-mentioned irradiated position in the ablation layer, the above-mentioned workpiece small piece existing at the position where the interface ablation occurs, is separated from the above-mentioned workpiece processing piece, and the above-mentioned workpiece small piece is placed on the above-mentioned object The separation step (invention 12).

In the above invention (Invention 12), by performing individualization on the surface of the workpiece maintained on the surface of the interface ablation layer opposite to the above-mentioned substrate in the above-mentioned preparatory step, it is possible to obtain The above workpiece small pieces are preferable (Invention 13).

In the above inventions (Inventions 12 and 13), it is preferable that the workpiece chip is at least one selected from a semiconductor package and a semiconductor device (Invention 14).

In the above-mentioned inventions (Inventions 12 to 14), a light-emitting device including a plurality of the above-mentioned light-emitting diodes is manufactured by using a light-emitting diode selected from miniature light-emitting diodes and micro-light-emitting diodes as the above-mentioned workpiece chip Better (invention 15).

In the above invention (Invention 15), it is preferable that the above-mentioned light-emitting device is a display (Invention 16). [Efficacy of the invention]

The workpiece processing sheet related to the present invention can be handled well even if it is a minute workpiece piece, and furthermore, according to the device manufacturing method related to the present invention, a device having excellent performance can be manufactured.

[Mode for Carrying Out the Invention]

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

In the workpiece processing chip 1 related to this embodiment, the interface ablation layer 11 can be used to maintain the workpiece chip. That is, the workpiece processing sheet 1 according to the present embodiment is a small workpiece laminated on the surface of the interface ablation layer 11 opposite to the base material 12, and can maintain its state.

Although the specific aspect of the above-mentioned maintenance is not limited, as a preferable example, the interface ablation layer 11 is maintained by exerting the adhesiveness to the workpiece chip. In this case, the interface ablation layer 11 preferably contains an adhesive as one of its constituent components as described below, in other words, it is preferably an adhesive layer.

In addition, the interface ablation layer 11 in this embodiment is one that performs interface ablation by irradiation of laser light. That is, the interface ablation layer 11 is one that locally performs interface ablation on the region irradiated with the above-mentioned laser light. And, as above-mentioned laser light, as long as can make interface ablation take place, will not be specifically limited, may have the laser light of any wavelength of ultraviolet region, visible light region and infrared region, wherein the laser light with the wavelength of ultraviolet region better.

In this specification, interfacial ablation refers to evaporating or volatilizing a part of the components constituting the interfacial ablation layer 11 by the energy of the above-mentioned laser light, whereby the gas generated is formed between the interfacial ablation layer 11 and the substrate. The interface between 12 stagnates to generate voids (bubbles). At this time, the shape of the interface ablation layer 11 is changed by the bubbles, and the workpiece pieces are peeled off from the interface ablation layer 11 to separate the workpiece pieces.

Then, the interface ablation layer 11 in this embodiment contains a photopolymerization initiator, and the workpiece processing sheet 1 according to this embodiment has an absorbance of light with a wavelength of 355 nm of 1.5 or more. In this way, since the photopolymerization initiator exists in the interface ablation layer 11 and the workpiece processing sheet 1 exhibits the above-mentioned absorbance, the efficiency of receiving energy from the laser light by the interface ablation layer 11 is improved. Thereby, interface ablation occurs efficiently, and the maintained workpiece small pieces can be separated well from the interface ablation layer 11 . In particular, the reduction of the irradiation amount of laser light necessary to sufficiently separate the workpiece small pieces can reduce the operating cost of the laser light irradiation device, and at the same time, only the target workpiece small pieces can be separated with good accuracy. Alternatively, damage to devices and the like due to excessive laser light irradiation can be prevented.

From the viewpoint of further improving the efficiency of receiving energy from laser light, the light absorbance is preferably 2.0 or higher, more preferably 2.2 or higher, particularly preferably 2.5 or higher, and further preferably 3.0 or higher. In addition, the upper limit of the above-mentioned absorbance is not particularly limited, and may be, for example, 6.0 or less. In addition, the detail of the measuring method of the said absorbance is as described in the following test example.

1. Interface ablation layer The specific composition and composition of the interface ablation layer 11 in this embodiment, as long as it can maintain the workpiece chip, and has properties such as interface ablation by irradiation of laser light, as long as it contains photopolymerization initiator At the same time, the above-mentioned absorbance can be achieved as the workpiece processing sheet 1, and is not particularly limited.

From the viewpoint of easily exhibiting properties such as being able to maintain workpiece chips, the interface ablation layer 11 preferably contains the above-mentioned adhesive as one of its constituent components. When the interface ablation layer 11 includes an adhesive, the interface ablation layer 11 is preferably formed of an adhesive composition containing a photopolymerization initiator.

(1) Photopolymerization initiator The kind of photopolymerization initiator in this embodiment is not specifically limited. As an example of a preferable photopolymerization initiator, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholinyl-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-(4-morphoxime Preferably at least one of olinophenyl)-butanone and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.

Along with the photopolymerization initiator described above, other photopolymerization initiators may be used in combination. 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, and benzoin isobutyl ether. , acetophenone, dimethylaminoacetylbenzene, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-diethoxy-2- Phenylacetylbenzene, 2-hydroxy-2-methyl-1-phenylpropan-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-phenyldiphenyl Ketone, 4,4'-diethylaminodiphenyl ketone, dichlorodiphenyl ketone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tertiary butylanthraquinone, 2-amine Anthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzene Methyl dimethyl ketal (benzil dimethyl ketal), acetyl xylylene dimethyl ketal, p-dimethylamino benzoate, oligo[2-hydroxy-2-methyl-1[4-( 1-methylvinyl)phenyl]acetone], 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, etc.

The photopolymerization initiator in this embodiment preferably has an absorption peak in the wavelength range of 200 nm to 400 nm. In this way, the interface ablation layer 11 absorbs the laser light efficiently, thereby becoming easy to perform interface ablation well. From this point of view, the lower limit of the above-mentioned range is particularly preferably 300 nm or more, and more preferably 330 nm or more. In addition, the upper limit of the above-mentioned range is preferably not more than 380 nm, more preferably not more than 370 nm.

In addition, the above-mentioned absorption peak can be specified by the following method. First, a photopolymerization initiator was 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 (for example, "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, especially 0.75 or more, and further preferably 1.0 or more. When the above-mentioned absorbance is 0.5 or more, the interface ablation layer 11 absorbs the laser light efficiently, thereby becoming easy to perform interface ablation well. In addition, although the upper limit 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 a methanol solution (when the photopolymerization initiator is insoluble in methanol, it is an acetonitrile solution) in which the concentration of the photopolymerization initiator is adjusted to 0.01% by mass, and the absorbance in the range of a wavelength of 200 to 500 nm in this solution, Measured using an ultraviolet-visible-near-infrared (UV-Vis-NIR) spectrophotometer (manufactured by Shimadzu Corporation, product name "UV-3600", optical path length: 10 mm).

The content of the photopolymerization initiator in the interface ablation layer 11 in this embodiment is preferably at least 1.8% by mass, especially preferably at least 3.0% by mass, further preferably at least 5.0% by mass. When the content of the photopolymerization initiator is 1.8% by mass or more, the interface ablation layer 11 absorbs laser light efficiently, thereby becoming easy to perform interface ablation well. In addition, the content of the photopolymerization initiator in the interface ablation layer 11 in this embodiment is preferably not more than 40.0 mass %, especially preferably not more than 30.0 mass %, further preferably not more than 25.0 mass %. When the content of the photopolymerization initiator is 40.0% by mass or less, the viscosity of the material for forming the interface ablation layer 11 becomes appropriate, and it is easy to ensure good film-forming properties.

In addition, when the interface ablation layer 11 in this embodiment is formed of the following adhesive composition, the photopolymerization initiator can also be formulated in the adhesive composition. In particular, when the photopolymerization initiator is compounded in the adhesive composition along with the following active energy ray-curable polymer (A), the compounding amount of the photopolymerization initiator in the adhesive composition is relative to the following activity 100 parts by mass of the energy ray-curable polymer (A), preferably at least 1.8 parts by mass, particularly preferably at least 3.0 parts by mass, further preferably at least 5.0 parts by mass. When the compounded amount of the photopolymerization initiator is 1.8 parts by mass or more, the interface ablation layer 11 absorbs the laser light efficiently, thereby facilitating favorable interface ablation. In addition, the compounded amount of the photopolymerization initiator in the above-mentioned adhesive composition is preferably not more than 40.0 parts by mass, particularly preferably not more than 30.0 parts by mass, based on 100 parts by mass of the active energy ray-curable polymer (A). , and further preferably 25.0 parts by mass or less. When the compounding quantity of a photoinitiator is 40.0 mass parts or less, the obtained adhesive becomes easy to exhibit desired adhesive force.

(2) Adhesive As mentioned above, the interface ablation layer 11 in this embodiment may also contain an adhesive agent in addition to a photopolymerization initiator. In this case, it is preferable that the interface ablation layer 11 is formed from an adhesive composition containing a photopolymerization initiator.

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

In addition, although the above-mentioned adhesive may be an adhesive that does not have active energy ray-curable properties, it is preferably an adhesive that has active energy ray-curable properties (hereinafter, sometimes referred to as "active energy ray-curable adhesive"). . When the interface ablation layer 11 is composed of an active energy ray-curable adhesive, the interface ablation layer 11 is hardened by irradiation of active energy rays, and the adhesion of the workpiece processing sheet 1 to the adherend can be easily reduced. .

In particular, the reduction of the adhesive force by the irradiation of active energy rays is carried out in conjunction with the above-mentioned interface ablation, and it becomes easy to separate the workpiece small pieces from the workpiece processing sheet 1 . In other words, before or simultaneously with the above-mentioned interface ablation, the adhesiveness is reduced by the irradiation of active energy rays, and the workpiece can be reliably removed from the workpiece processing sheet 1 according to this embodiment. Separation of small pieces. In addition, the irradiation amount of laser light necessary for sufficient separation of the workpiece small pieces can be further reduced.

The active energy ray-curable adhesive may be a polymer having active energy ray-curable properties as a main component, or an active energy ray non-curable polymer (polymer not curable by active energy ray). ) and a mixture of monomers and/or oligomers having at least one active energy ray-curable group as the main component. In addition, the active energy ray-curable adhesive may be a mixture of an active energy ray-curable polymer and a monomer and/or oligomer having at least one active energy ray-curable group.

The aforementioned active energy ray curable polymer is a (meth)acrylate (co)polymer (A) (hereinafter , sometimes called "active energy ray-curable polymer (A)". This active energy ray-curable polymer (A) is such that the acrylic copolymer ( a1), preferably obtained by reacting with an unsaturated group-containing compound (a2) having a functional group bonded to this functional group. And, in this specification, the so-called (meth)acrylate refers to acrylate and methacrylate. Other similar terms are also the same. Furthermore, "polymer" also includes the concept of "copolymer".

The acrylic copolymer (a1) preferably contains a structural unit derived from a functional group-containing monomer and a structural unit derived from a (meth)acrylate monomer or a derivative thereof.

The functional group-containing monomer as a constituent unit of the acrylic copolymer (a1) has a polymerizable double bond in the molecule, and a functional group such as a hydroxyl group, a carboxyl group, an amino group, a substituted amino group, an epoxy group, etc. The monomer is better.

Examples of hydroxyl-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, (meth)acrylic acid 2-Hydroxybutyl, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate etc. can be used individually or in combination of 2 or more types.

Examples of the carboxyl group-containing monomer include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. These may be used individually or in combination of 2 or more types.

Examples of the amino group-containing monomer or substituted amino group-containing monomer include aminoethyl (meth)acrylate, n-butylaminoethyl (meth)acrylate, and the like. These may be used individually or in combination of 2 or more types.

As the (meth)acrylate monomer constituting the acrylic copolymer (a1), other than alkyl (meth)acrylates having an alkyl group having 1 to 20 carbon atoms are preferably used, for example, in A monomer having an alicyclic structure in the molecule (monomer containing an alicyclic structure).

As the alkyl (meth)acrylate, especially the alkyl (meth)acrylate whose alkyl group has 1 to 18 carbon atoms, for example, methyl (meth)acrylate, ethyl (meth)acrylate, ester, propyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc. These may be used alone or in combination of two or more.

As monomers containing an alicyclic structure, for example, cyclohexyl (meth)acrylate, dicyclopentyl (meth)acrylate, adamantyl (meth)acrylate, Camphenyl, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and the like. These may be used alone or in combination of two or more.

The proportion of the acrylic copolymer (a1) containing the structural unit derived from the above-mentioned functional group-containing monomer is preferably at least 1% by mass, particularly preferably at least 5% by mass, and more preferably at least 10% by mass . In addition, the proportion of the acrylic copolymer (a1) containing the structural unit derived from the above-mentioned functional group-containing monomer is preferably at most 35% by mass, particularly preferably at most 30% by mass, and further preferably at most 25% by mass. better.

Furthermore, the proportion of the acrylic copolymer (a1) containing the constituent units derived from (meth)acrylate monomers or derivatives thereof is preferably 50% by mass or more, especially 60% by mass or more, Furthermore, it is more preferably 70% by mass or more. In addition, the proportion of the acrylic copolymer (a1) containing structural units derived from (meth)acrylate monomers or derivatives thereof is preferably at most 99% by mass, particularly preferably at most 95% by mass, and further It is preferably 90% by mass or less.

The acrylic copolymer (a1) can be obtained by copolymerizing the above-mentioned functional group-containing monomer with a (meth)acrylate monomer or its derivatives by a common method. However, it can also be obtained by Copolymerization of dimethylacrylamide, vinyl formate, vinyl acetate, styrene, etc. other than these monomers.

Active energy rays can be obtained by reacting the above-mentioned acrylic copolymer (a1) having a functional group-containing monomer unit with an unsaturated group-containing compound (a2) having a functional group bonded to the functional group. Hardening type polymer (A).

The functional group which the unsaturated group containing compound (a2) has can be selected suitably according to the kind of the functional group of the functional group containing monomeric unit which the acrylic-type copolymer (a1) has. For example, when the functional group that the acrylic copolymer (a1) has is a hydroxyl group, an amino group, or a substituted amino group, the functional group that the unsaturated group-containing compound (a2) has is an isocyanate group or an epoxy group. Preferably, when the functional group of the acrylic copolymer (a1) is an epoxy group, the functional group of the unsaturated group-containing compound (a2) may be an amine group, a carboxyl group or an aziridinyl group (aziridinyl) better.

In addition, in the above-mentioned unsaturated group-containing compound (a2), it is preferable that one molecule contains at least one energy-ray polymerizable carbon-carbon double bond, preferably 1 to 6, and more preferably 1 to 4. indivual. Specific examples of such an unsaturated group-containing compound (a2) include, for example, 2-methacryloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl methacryl isocyanate, methacryl isocyanate, allyl isocyanate, 1,1-(bisacryloxymethyl)ethyl isocyanate; diisocyanate compound or polyisocyanate compound, with hydroxyethyl (meth)acrylate Acryl monoisocyanate compound obtained by reaction; diisocyanate compound or polyisocyanate compound, polyol compound, and acryl monoisocyanate compound obtained by reaction of hydroxyethyl (meth)acrylate; (meth)acrylic acid Glycidyl ester; (meth)acrylic acid, 2-(1-aziridinyl)ethyl (meth)acrylate, 2-vinyl-2-oxazoline, 2-isopropenyl-2-oxazole phylloline etc.

The proportion of the above-mentioned unsaturated group-containing compound (a2) relative to the number of moles of the functional group-containing monomer of the above-mentioned acrylic copolymer (a1) is preferably 50 mole % or more, especially 60 mole % or more is preferable, and further preferably more than 70 mole %. In addition, the proportion of the above-mentioned unsaturated group-containing compound (a2) relative to the number of moles of the functional group-containing monomer of the above-mentioned acrylic copolymer (a1) is preferably 95 mole % or less, especially 93 It is preferably not more than mol%, more preferably not more than 90 mol%.

In the reaction between the acrylic copolymer (a1) and the unsaturated group-containing compound (a2), the functional groups corresponding to the acrylic copolymer (a1) and the unsaturated group-containing compound (a2) have The combination of functional groups can appropriately select the reaction temperature, pressure, solvent, time, presence or absence of a catalyst, and the type of catalyst. In this way, the functional group present in the acrylic copolymer (a1) reacts with the functional group in the unsaturated group-containing compound (a2) to introduce the unsaturated group into the acrylic copolymer (a1). In the side chain, the active energy ray-curable polymer (A) can be obtained.

The weight average molecular weight (Mw) of the active energy ray-curable polymer (A) thus obtained is preferably at least 10,000, particularly preferably at least 50,000, and further preferably at least 100,000. In addition, the weight average molecular weight (Mw) is preferably at most 3 million, particularly preferably at most 2 million, and further preferably at most 1.5 million. In addition, the weight average molecular weight (Mw) in this specification is the value measured by gel permeation chromatography (GPC method) in conversion of standard polystyrene.

Even when the active energy ray-curable adhesive contains an active energy ray-curable polymer such as the active energy ray-curable polymer (A) as a main component, the active energy ray-curable adhesive can further Contains energy ray curable monomers and/or oligomers (B).

As the active energy ray-curable monomer and/or oligomer (B), for example, a polyhydric alcohol, an ester of (meth)acrylic acid, or the like can be used.

Examples of the relevant active energy ray-curable monomers and/or oligomers (B) include monofunctional acrylates such as cyclohexyl (meth)acrylate and isobornyl (meth)acrylate. trimethylolpropane tri(meth)acrylate, neopentylthritol tri(meth)acrylate, neopentylthritol tetra(meth)acrylate, dipenteoerythritol hexa(meth)acrylate ester, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dimethylol tricyclic Polyfunctional acrylates such as decane di(meth)acrylate, polyester oligo(meth)acrylate, urethane oligo(meth)acrylate, and the like.

For the active energy ray-curable polymer (A), when the active energy ray-curable monomer and/or oligomer (B) is formulated, the active energy ray-curable monomer and the active energy ray-curable adhesive in the active energy ray-curable adhesive The content of/or the oligomer (B) is preferably more than 0 parts by mass, particularly preferably 60 parts by mass or more, based on 100 parts by mass of the active energy ray-curable polymer (A). In addition, the content is preferably at most 250 parts by mass, particularly preferably at most 200 parts by mass, based on 100 parts by mass of the active energy ray-curable polymer (A).

Next, for the active energy ray-curable adhesive, a mixture of an active energy ray non-curable polymer component and a monomer and/or oligomer having at least one active energy ray-curable group as a main component The situation is described below.

As the active energy ray non-curable polymer component, for example, the same component as the above-mentioned acrylic copolymer (a1) can be used.

As the monomer and/or oligomer having at least one active energy ray-curable group, the same ones as those for the above-mentioned component (B) can be selected. The compounding ratio of the active energy ray non-curable polymer component to the monomer and/or oligomer having at least one active energy ray-curable group is based on 100 parts by mass of the active energy ray non-curable polymer component, The monomer and/or oligomer having at least one active energy ray-curable group is preferably at least 1 part by mass, particularly preferably at least 60 parts by mass. In addition, the compounding ratio is 200 parts by mass or less of the monomer and/or oligomer having at least one active energy ray-curable group relative to 100 parts by mass of the active energy ray non-curable polymer component. Preferably, especially less than 160 parts by mass.

(3) Other ingredients In the above-mentioned adhesive composition, other appropriate components can also be compounded. Examples of other components include active energy ray non-curable polymer components or oligomer components (D), crosslinking agents (E) and the like.

As the active energy ray non-hardening polymer component or oligomer component (D), for example, polyacrylate, polyester, polyurethane, polycarbonate, polyolefin, etc., the weight average molecular weight (Mw) is 3000 ~2.5 million polymers or oligomers are preferred. By blending this component (D) into an energy ray-curable adhesive, the adhesiveness and peelability before curing, the strength after curing, the adhesiveness with other layers, the storage stability, and the like can be improved. The compounding quantity of this component (D) is not specifically limited, It is determined suitably within the range of more than 0 mass part and 50 mass parts or less with respect to 100 mass parts of energy ray hardening type copolymers (A).

From the viewpoint of easy adjustment of the storage modulus of the interface ablation layer 11 within a desired range, it is preferable to use a crosslinking agent (E). As the crosslinking agent (E), a polyfunctional compound having reactivity with a functional group contained in the active energy ray-curable copolymer (A) or the like can be used. Examples of such polyfunctional compounds include isocyanate compounds, epoxy compounds, amine compounds, melamine compounds, aziridine compounds, hydrazine compounds, aldehyde compounds, and oxazoline compounds. , metal alkoxide compound, metal chelate compound, metal salt, ammonium salt, reactive phenol resin, etc.

The compounded amount of the crosslinking agent (E) is preferably at least 0.001 parts by mass, particularly preferably at least 0.1 parts by mass, and further preferably at least 0.2 parts by mass, based on 100 parts by mass of the active energy ray-curable copolymer (A). better. In addition, the compounded amount of the crosslinking agent (E) is preferably not more than 20 parts by mass, particularly preferably not more than 10 parts by mass, and further preferably not more than 5 parts by mass relative to 100 parts by mass of the active energy ray-curable copolymer (A). Servings or less are preferred.

In addition, examples of other components that can be formulated in the above-mentioned adhesive composition include additives such as thickeners, coloring materials such as dyes and pigments, flame retardants, fillers, and antistatic agents. In addition, it is preferable that the above-mentioned adhesive composition does not contain a gas generating agent from the viewpoint of making separation of the workpiece small pieces easy to occur favorably. When a gas generating agent is used, gas is generated in the entire area of the interface ablation layer 11 . In this case, it is difficult to cause interface ablation only at a desired position, and it is difficult to separate only the workpiece small pieces located at this position, and the separation of the workpiece small pieces cannot be performed satisfactorily.

(4) The thickness of the interface ablation layer The thickness of the interface ablation layer 11 in this embodiment is preferably at least 3 μm, especially preferably at least 20 μm, and more preferably at least 25 μm. In addition, the thickness of the interface ablation layer 11 is preferably not more than 100 μm, especially not more than 50 μm, and more preferably not more than 40 μm. When the thickness of the interface ablation layer 11 is within the above-mentioned range, it becomes easy to achieve both maintenance of the workpiece small pieces on the interface ablation layer 11 and separation of the workpiece pieces by interface ablation.

2. Substrate The composition and physical properties of the substrate 12 in this embodiment are not particularly limited. It is preferable that the base material 12 is made of resin from the viewpoint of easily exhibiting desired functions of the workpiece processing sheet 1 . When the base material 12 is made of a resin, examples of the resin include polyester-based materials such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. Resin; polyolefin-based resins such as polyethylene, polypropylene, polybutene, polybutadiene, polymethylpentene, ethylene-norbornene copolymer, and norbornene resin; ethylene-vinyl acetate Ester copolymers; vinyl copolymer resins such as ethylene-(meth)acrylic acid copolymers, ethylene-methyl(meth)acrylate copolymers, and other ethylene-(meth)acrylate copolymers; Polyvinyl chloride-based resins such as polyvinyl chloride and vinyl chloride copolymer; (meth)acrylate copolymer; polyurethane; polyimide; polystyrene; polycarbonate; fluororesin, etc. In addition, the resin constituting the base material 12 may be one in which the above-mentioned resin is cross-linked, or one in which the above-mentioned resin is modified such as an ionomer. In addition, the base material 12 may be a single-layer film formed of the above-mentioned resin, or a laminated film formed by laminating a plurality of layers of this film. In this laminated film, the materials constituting each layer may be the same or different.

The surface of the base material 12 in this embodiment may be subjected to surface treatment such as oxidation, roughening, or primer treatment for the purpose of improving the adhesion to the interface ablation layer 11 . Examples of the above-mentioned oxidation method include corona discharge treatment, plasma discharge treatment, chromating treatment (wet method), flame treatment, hot air treatment, ozone, and ultraviolet irradiation treatment. , for example, sand blasting, melt blowing, etc.

The base material 12 in this embodiment may contain various additives such as colorants, flame retardants, plasticizers, antistatic agents, lubricants, and fillers. In addition, when the interface ablation layer 11 contains a material hardened by active energy rays, it is preferable that the base material 12 has a 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, it can be produced by molding the resin into a sheet shape by melt extrusion methods such as T-die method and circular die method; calendar method; solution method such as dry method and wet method, and the like.

The thickness of the substrate 12 in this embodiment is preferably at least 10 μm, especially preferably at least 30 μm, and further preferably at least 50 μm. In addition, the thickness of the substrate 12 is preferably not more than 500 μm, more preferably not more than 300 μm, especially preferably not more than 200 μm, more preferably not more than 150 μm, most preferably not more 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 in a specific balance, and becomes easy to perform good processing of workpiece small pieces.

3. Peeling sheet In this embodiment, when the interface ablation layer 11 contains an adhesive as one of its constituent components, it is also possible to protect the surface of the interface ablation layer 11 until the surface of the interface ablation layer 11 opposite to the base material 12 is attached to the workpiece chip. For the purpose, layer the release sheet on the surface.

The structure of the above-mentioned release sheet may be arbitrary, and for example, a plastic film is subjected to a release treatment with a release agent or the like. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyester films such as polypropylene and polyethylene. Polyolefin film. As the release agent, silicone-based, fluorine-based, long-chain alkane-based, etc. can be used. Among them, silicone-based ones that are inexpensive and can provide stable performance are 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 according to this embodiment, an adhesive layer may be formed on the surface of the interface ablation layer 11 opposite to the substrate 12 . In this sheet, a workpiece is attached to the surface of the adhesive layer opposite to the interface ablation layer 11, and the workpiece is cut together with the adhesive layer to obtain a workpiece chip in which the individualized adhesive layer is laminated. The wafer is easily fixed on the object on which the workpiece small piece is mounted through the singulated adhesive layer. As the material constituting the adhesive layer, those containing thermoplastic resin and low molecular weight thermosetting adhesive components, those containing B stage (B stage, semi-cured) thermosetting adhesive components, etc. are preferably used.

In addition, in the workpiece processing sheet 1 according to this embodiment, a protective film forming layer may be laminated on the surface of the interface ablation layer 11 opposite to the base material 12 . Such a sheet is obtained by attaching the surface of the protective film-forming layer opposite to the interface ablation layer 11 to a workpiece, cutting the workpiece together with the protective film-forming layer, and obtaining a laminated protective-film-forming layer in individual pieces. small pieces of workpiece. As the workpiece, it is preferable to use one with a circuit formed on one surface, and in this case, a protective film forming layer is usually deposited on the surface opposite to the surface on which the circuit is formed. By hardening the individualized protective film forming layer at a specific timing, a protective film having sufficient durability can be formed on a small workpiece. The protective film forming layer is preferably formed of an uncured curable adhesive.

5. Physical properties of the workpiece processing sheet The workpiece processing sheet 1 related to this embodiment preferably has an adhesion force to the mirror surface of the silicon wafer of 10 mN/25 mm or more, especially 100 mN/25 mm or more, and further preferably 200 mN/25 mm or more. When the said adhesive force is 10 mN/25mm or more, it becomes easy to fix adhered objects, such as a small workpiece|work piece, on the workpiece|work handling sheet 1 favorably, and it becomes what is excellent in workability. In addition, the above-mentioned adhesive force is preferably not more than 30000 mN/25mm, especially preferably not more than 15000 mN/25mm, and is further preferably not more than 10000 mN/25mm. When the said adhesive force is 30000mN/25mm or less, it becomes easy to perform separation of a workpiece|work small piece by laser light irradiation favorably.

In addition, when the interface ablation layer 11 in this embodiment is an adhesive layer composed of the above-mentioned active energy ray curable adhesive, it is preferable to satisfy the following conditions regarding the adhesive force after ultraviolet irradiation. In other words, the surface of the interface ablation layer 11 opposite to the substrate 12 is attached to the mirror surface of the silicon wafer, and the interface ablation layer 11 is irradiated with ultraviolet rays using a high-pressure mercury lamp to harden the interface ablation layer 11. , the adhesion to the mirror surface of the silicon wafer is preferably less than 2000mN/25mm, especially less than 1000mN/25mm, and further preferably less than 200mN/25mm. When the above-mentioned adhesive force is 2000 mN/25 mm or less, it becomes easy to separate the workpiece small pieces well by subsequent interface ablation. In addition, the lower limit of the adhesive force is not particularly limited, and may be, for example, 5 mN/25 mm or more, especially 10 mN/25 mm or more, and may be 20 mN/25 mm or more.

In addition, the detail of the measuring method of these adhesive forces is as described in the following test example.

6. Manufacturing method of workpiece handling sheet The method of manufacturing the workpiece processing sheet 1 according to this embodiment is not particularly limited. For example, the interface ablation layer 11 can be directly formed on the substrate 12 , or, after the interface ablation layer 11 is formed on a processing sheet, the interface ablation layer 11 can be transferred onto the substrate 12 .

When the interface ablation layer 11 contains an adhesive as one of its components, the interface ablation layer 11 can be formed by a known method. For example, a coating liquid containing an adhesive composition for forming the interface ablation layer 11 and, if necessary, a solvent or a dispersion medium is prepared. Then, the above-mentioned coating liquid is applied to one side of the base material or the side with releasability of the release sheet (hereinafter, sometimes referred to as "release surface"). Next, the interface ablation layer 11 can be formed by drying the obtained coating film.

Coating of the above-mentioned coating liquid can be performed by a known method, for example, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, etc. conduct. Further, the properties of the coating liquid are not particularly limited as long as it can be applied, and components for forming the interface ablation layer 11 may be contained as solutes or dispersoids. In addition, when the interface ablation layer 11 is formed on the release sheet, the release sheet can also be used as a process material for peeling off, and can also protect the interface ablation layer 11 during the period of sticking to the adherend.

When the adhesive composition for forming the interface ablation layer 11 contains the above-mentioned crosslinking agent, by changing the above-mentioned drying conditions (temperature, time, etc.), or by additionally providing heat treatment, the polymer component in the coating film The crosslinking reaction with the crosslinking agent progresses, and it is preferable that a crosslinked structure can be formed at a desired density in the interface ablative layer 11 . Moreover, in order to make the above-mentioned cross-linking reaction fully proceed, after the completion of the workpiece processing sheet 1, for example, it can also be left standing for several days at 23° C. in an environment with a relative humidity of 50% to perform so-called aging.

7. How to use the workpiece processing sheet The workpiece processing chip 1 according to this embodiment can be suitably used for handling small workpieces. As described above, in the workpiece processing sheet 1 according to the present embodiment, since the interface ablation layer 11 is efficiently ablated by the irradiation of laser light, the workpiece small pieces maintained on the interface ablation layer 11 can be processed at a high rate. Precision separates for a specific location.

As an example of the method of using the workpiece processing sheet 1 according to this embodiment, by causing the interface ablation layer 11 to locally ablate the interface, the surface opposite to the base material 12 maintained in the interface ablation layer 11 is exemplified. A method of selectively separating arbitrary workpiece small pieces from the interface ablation layer 11 among the plurality of workpiece small pieces on the surface.

In the above method of use, the plurality of workpiece small pieces maintained on the interface ablation layer 11 may be workpieces (materials to be used as workpiece small pieces) that will be maintained on the surface of the interface ablation layer 11 opposite to the base material 12 , which is obtained by sliced on this face. In other words, the small pieces of the workpiece can also be obtained by cutting the workpiece on the interface ablation layer 11 . Alternatively, the workpiece chip may be formed independently of the workpiece processing sheet 1 according to this embodiment, and then placed on the interface ablation layer 11 .

Furthermore, when the workpiece processing sheet 1 according to this embodiment includes the above-mentioned adhesive layer and protective film forming layer, it is preferable to cut these layers and the workpiece on the interface ablation layer 11 . In this way, it is possible to obtain a workpiece chip in which such layers are laminated and separated into pieces.

Although the shape and size of the workpiece piece in this embodiment are not particularly limited, the size of the workpiece piece is preferably 10 μm ² or more in plan view, especially 100 μm ² or more. In addition, the area of the small piece of workpiece is preferably less than 1mm ² , especially less than 0.25mm ² . In addition, as the dimensions of the workpiece piece, when the workpiece piece is rectangular, the smallest side of the workpiece piece is preferably 2 μm or more, especially 5 μm or more, and further preferably 10 μm or more. In addition, the above-mentioned smallest side is preferably 1 mm or less, especially preferably 0.5 mm or less. Specific examples of the dimensions 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 according to the present embodiment can handle such fine workpiece pieces, especially fine workpiece pieces that are not easily separated from the needle point-like sheet. On the other hand, the workpiece processing sheet 1 according to this embodiment is intended for relatively large workpieces such as those with an area exceeding 1 mm ² (for example, 1 mm ² to 2000 mm ² ) and those with a thickness of 1 to 10000 μm (for example, 10 to 1000 μm). Small piece, still handles well.

Examples of workpiece chips include semiconductor modules, semiconductor devices, and more specifically, micro light emitting diodes, power elements, MEMS (Micro Electro Mechanical Systems), and the like. Among them, it is suitable for the workpiece small pieces to be light emitting diodes, especially light emitting diodes selected from mini light emitting diodes and micro light emitting diodes. In recent years, research has been conducted on the development of devices in which miniature light-emitting diodes and micro-light-emitting diodes are arranged at a high density. In the manufacture of such devices, it is very suitable for this implementation that can operate these light-emitting diodes with high precision. Morphology-related workpiece processing piece 1.

Hereinafter, as a specific usage example of the workpiece processing sheet 1 , a device manufacturing method will be described with reference to FIG. 2 . This device manufacturing method includes at least three steps: a preparation step (FIG. 2(a)), an arrangement step (FIG. 2(b)), and a separation step (FIGS. 2(c) and (d)).

In the preparatory step, as shown in FIG. 2(a), in the workpiece processing sheet 1 according to this embodiment, a laminate in which a plurality of workpiece small pieces 2 are maintained on the surface on the interface ablation layer 11 side is prepared. . This laminate can be prepared by placing separately produced workpiece small pieces 2 on the workpiece processing sheet 1, or the workpiece held on the surface on the interface ablation layer 11 side can be individualized on the surface. (ie, cutting) and prepare. This cleavage can be performed by a known method.

The shape and size of the workpiece piece 2 are as above, and are not particularly limited, and the preferred size is also as above. Specific examples of the workpiece chip 2 include, as above, semiconductor components, semiconductor devices, etc., especially light emitting diodes such as miniature light emitting diodes and micro light emitting diodes.

In the subsequent arranging step, as shown in FIG. 2( b ), the laminate is arranged so as to face the surface of the laminate 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 corresponding to the device to be manufactured, but if the workpiece chip 2 is a light-emitting diode, as specific examples of the object 3, substrates, sheets, reels (reel) etc., and are particularly suitable for wiring boards provided with wiring.

After that, in the separation step, first, as shown in FIG. 2( c ), the interface ablation layer 11 in the above-mentioned laminate is irradiated with laser light to the position where at least one workpiece small piece 2 is attached. This irradiation may be performed simultaneously for a plurality of positions where the workpiece small piece 2 is attached, or may be performed sequentially for these positions. Irradiation conditions of laser light are not limited as long as interface ablation can occur. As a device for irradiation, known ones can be used.

By the above irradiation, as shown in FIG. 2( d ), interface ablation can occur at the irradiated position in the interface ablation layer 11 . Specifically, by irradiation of laser light, in the region of the interface ablation layer 11 close to the substrate 12 , the components constituting the region evaporate or volatilize, forming the reaction region 13 . Then, the gas generated by the above-mentioned evaporation or volatilization stays between the substrate 11 and the reaction region 13 to form the bubbles 5 . Due to the formation of the bubbles 5, the local interface ablation layer 11 is deformed at the position of the workpiece piece 2', and the workpiece piece 2' is separated so that the interface ablation layer 11 is peeled off. Through the above, the workpiece small piece 2' existing at the position where the interface ablation occurs can be placed on the object 3.

Moreover, the reaction region 13 and the bubble 5 generated by the irradiation of laser light usually remain after the separation of the workpiece small piece 2'. In FIG. 3 , the state of separating the workpiece small pieces 2 by sequentially irradiating laser light is shown, especially the state after separation (two on the left), the state during separation (center), and the state before separation (two on the right) . As shown in the figure, generally, the expanded bubble 5 after separation is slightly deflated compared with the expanded bubble 5 being separated.

In addition, when the interface ablation layer 11 in this embodiment is the adhesive layer composed of the above-mentioned active energy ray-curable adhesive, the above-mentioned device manufacturing method may include a subsequent hardening step. In other words, it is also possible to provide the entire interface ablation layer 11 in the laminate composed of a plurality of workpiece small pieces 2 maintained on the surface of the interface ablation layer 11, or for the interface ablation layer in the above-mentioned laminate. A hardening step in which at least one workpiece small piece 2 is attached in the etched layer 11 and irradiated with active energy rays to harden the interface ablated layer 11 entirely or locally. This hardening step can be carried out before the above-mentioned separation step, or can also be carried out simultaneously with the above-mentioned separation step.

As mentioned above, the whole or part of the interface ablation layer 11 is hardened by the irradiation of active energy rays, so that the adhesion of the workpiece processing sheet 1 to the workpiece small piece 2 can be reduced. Small piece 2 was separated. Irradiation of active energy rays in the curing step can be performed using known methods, for example, using an ultraviolet irradiation device equipped with a high-pressure mercury lamp as a light source and an ultraviolet LED, and a laser light irradiation device that can also be used in the separation step. When performing the curing step and the separating step simultaneously, it is preferable to perform irradiation of the laser light 4 using a laser light irradiation device also as irradiation of active energy rays.

The above device manufacturing method may include steps other than the preparation step, arrangement step, hardening step, and separation step. For example, at any point in time between the preparation step and the separation step, grinding, die bonding, wire bonding, molding, examination, transfer ( transfer) steps.

According to the device manufacturing method described above, various devices can be manufactured by appropriately selecting the workpiece 2 and the object 3 to be used. For example, when a light-emitting diode selected from mini light-emitting diodes and micro-light-emitting diodes is used as the workpiece chip 2, a light-emitting device equipped with a plurality of such light-emitting diodes can be manufactured, and more specifically, a light-emitting device can be manufactured. monitor. In particular, displays with micro light emitting diodes as pixels and displays with a plurality of miniature light emitting diodes as backlights can be manufactured.

In addition, the workpiece processing sheet 1 according to this embodiment can also be used in a method of selectively removing a specific workpiece small piece 2 among a plurality of workpiece small pieces 2 provided on the sheet.

For example, after manufacturing a plurality of light-emitting diodes and the like on the workpiece processing sheet 1 according to this embodiment, detection of the light-emitting diodes is performed on the sheet. Only light-emitting diodes identified as defective products can be caused to undergo interfacial ablation to detach and remove from the workpiece processing sheet 1 .

Furthermore, a collection of such good products can be transferred from the workpiece processing sheet 1 to the sheet for conveyance. At this time, when the interface ablation layer 11 is composed of the above-mentioned active energy ray-curable adhesive, the adhesive force of the workpiece processing sheet 1 to the light-emitting diode is reduced by irradiating the interface ablation layer 11 with active energy rays. , A collection of good products can be transferred favorably to a shipping sheet. Thereafter, by arranging a separately produced good product at the position where the defective product was removed, the workpiece processing sheet 1 provided with only the good product can be obtained.

As mentioned above, in the method of removing defective products by interface ablation, since there is no need to stretch the sheet and pick up defective products, it is not easy to change the spacing of the light emitting diodes and shift the position. Therefore, it becomes easy to transfer to the sheet|seat for conveyance.

The embodiments described above are described for easy understanding of the present invention, and are not described for limiting the present invention. Therefore, the gist of each element disclosed in the above embodiments includes all design changes and equivalents in the technical field to which the present invention pertains.

For example, between the interface ablation layer 11 and the substrate 12 in the workpiece processing sheet 1 related to this embodiment, or on the surface of the substrate 12 opposite to the interface ablation layer 11, other substrates may be laminated. Floor. As a specific example of this other layer, an adhesive layer is mentioned. At this time, the 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 does not easily absorb active energy rays and does not shield active energy rays. At this time, when the laser light is irradiated through the adhesive layer, the laser light easily reaches the interface ablation layer 11, and the interface ablation can be favorably generated. 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, even when the above-mentioned laser light is irradiated, the above-mentioned adhesive layer will not be cured, and thus it becomes possible to prevent unintended removal of the workpiece processing sheet 1 from the transparent substrate. peel off. Although it does not specifically limit as thickness of the said adhesive layer, For example, 5-50 micrometers is preferable. [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 70 mass parts of 2-ethylhexyl acrylate and 30 mass parts of 2-hydroxyethyl acrylate were polymerized by the solvent polymerization method, and the (meth)acrylate polymer was obtained. For this (meth)acrylate polymer, react it with 90 mole % of methacryloxyethyl isocyanate (MOI) relative to the 2-hydroxyethyl acrylate to obtain A (meth)acrylate copolymer having an active energy ray-curable group (active energy ray-curable polymer (A)). The weight average molecular weight (Mw) of this active energy ray curable polymer (A) was measured by the above-mentioned method, and it was 800,000.

100 parts by mass (in terms of solid content, the same below) of the active energy ray-curable polymer (A) obtained above was mixed with trimethylolpropane-modified methylene diisocyanate (Tosoh Co., Ltd., trade name "Coronate L") 2.5 parts by mass, and ethyl ketone as a photopolymerization initiator, 1-[9-ethyl-6-(2-methylbenzoyl)-9H- Carbazole-3-yl]-, 1-(O-acetyloxime) (manufactured by BASF Corporation, product name "Irugacure OXE02") 4 parts by mass were mixed in a solvent to obtain an adhesive composition with a solid content concentration of 30% by mass Coating solution for objects.

(2) Production of workpiece handling sheet On the easy-adhesive side of a polyethylene terephthalate film (manufactured by Toyobo Co., Ltd., product name "COSMOSHINE A4100", thickness: 50 μm) that has been easily-adhesively treated on one side as a base material, apply the above-mentioned step (1) The obtained coating liquid of the adhesive composition is dried by heating the obtained coating film. In this way, an interface ablation layer (adhesive layer) with a thickness of 30 μm was formed on the substrate.

Next, a release sheet (manufactured by LINTEC Corporation) formed of a silicone-based release agent layer was placed on the side of the interface ablation layer opposite to the substrate, and one side of a polyethylene terephthalate film with a thickness of 38 μm. , product name "SP-PET381031") peeling side bonding. In this way, the workpiece processing sheet is obtained by sequentially laminating the release sheet, the interface ablation layer and the base material.

(3) Determination method of weight average molecular weight The said weight average molecular weight (Mw) is the weight average molecular weight of the conversion standard polystyrene measured (GPC measurement) under the following conditions using the gel permeation chromatography (GPC). ＜Measurement conditions＞ ． Measuring device: Tosoh Co., Ltd., HLC-8320 ． GPC column (pass through in the following order): manufactured by Tosoh Co., Ltd. TSK gel super H-H TSK gel super HM-H TSK gel super H2000 ． Determination of solvent: tetrahydrofuran ． Measurement temperature: 40°C.

[Examples 2-3 and Comparative Examples 1-3] Except having changed the kind and content of a photoinitiator as shown in Table 1, it carried out similarly to Example 1, and manufactured the workpiece processing sheet. In addition, Comparative Example 1 is an example in which no photopolymerization initiator was used.

[Test Example 1] (Measurement of Ultraviolet Absorbance) The release sheet was peeled off from the workpiece processing sheets produced in the examples and comparative examples to expose the interface ablation layer. For this workpiece treatment sheet, use ultraviolet light. Visible light. The ultraviolet absorbance was measured with a near-infrared spectrophotometer (manufactured by Shimadzu Corporation, product name "UV-3600") and an attached large sample chamber (manufactured by Shimadzu Corporation, product name "MPC-3100"). This measurement was carried out by irradiating the surface of the interface ablation layer side with light having a wavelength of 355 nm with a slit width of 20 nm using the integrating sphere built in the above-mentioned large sample chamber. The results are shown in Table 1.

[Test Example 2] (Measurement of Adhesive Force) The workpiece processing sheets manufactured in Examples and Comparative Examples were cut into short strips with a width of 25 mm. The peeling sheet was peeled off from the obtained strip-shaped workpiece processing sheet, and the exposed surface of the exposed interface ablation layer was subjected to a temperature of 23° C. In an environment with a relative humidity of 50%, use a 2kg rubber roller (rubber roller) for attachment, and let it stand for 20 minutes as a sample for adhesion measurement.

Thereafter, using a universal tensile testing machine (manufactured by ORIENTEC Corporation, product name "TENSILON UTM-4-100"), the workpiece handling sheet was peeled from the silicon wafer at a peeling speed of 300 mm/min and a peeling angle of 180°. JIS Z0237:2009 is the standard 180° peeling method to measure the adhesion (mN/25mm) to the mirror surface of the silicon wafer. The results are shown in Table 1 as the adhesive force before ultraviolet irradiation.

In addition, for the interface ablation layer in the sample for adhesion measurement obtained in the same manner as above, an ultraviolet irradiation device (manufactured by LINTEC Corporation, product name "RAD-2000") equipped with a high-pressure mercury lamp as a light source was used through the substrate. , and irradiate ultraviolet rays (illuminance: 230mW/cm ² , light intensity: 190mJ/cm ² ) to harden the interface ablation layer. The adhesive force (mN/25mm) to the mirror surface of a silicon wafer was measured similarly to the above about the sample for adhesive force measurement after this ultraviolet-ray irradiation. The results are shown in Table 1 as adhesive force after ultraviolet irradiation.

[Test Example 3] (Evaluation of suitability for laser peeling) (1) Preparation of wafer on workpiece handling sheet (preparation step) On one side of a silicon wafer (#2000, thickness: 350 μm), a dicing sheet (LINTEC Corporation, product name "D-485H") adhesive surface. Next, a ring frame for dicing is attached to the peripheral portion (the position not overlapping the silicon wafer) of the above-mentioned adhesive surface on the dicing sheet. Further, the cutting pieces are cut according to the outer diameter of the ring frame. Thereafter, the silicon wafer was diced into wafers having a size of 300 μm×300 μm using a dicing device (manufactured by Disco Corporation, product name “DFD6362”). Thereafter, ultraviolet rays (illuminance: 230 mW/cm ² , light intensity: 190 mJ/cm ² ) were irradiated on the dicing sheet to obtain a laminate in which a plurality of wafers were placed on the dicing sheet.

Next, the peeling sheet was peeled off from the workpiece handling sheets produced in Examples and Comparative Examples, and the exposed surface exposed by this was bonded to the surface of the laminate obtained above where a plurality of wafers existed. Thereafter, the diced sheets are peeled off from the plurality of wafers. In this way, the plurality of wafers are transferred from the dicing sheet to the workpiece processing sheet, and a laminate in which the plurality of wafers are provided on the workpiece processing sheet is obtained.

(2) Separation of wafers irradiated with laser light (separation step) With respect to the laminate obtained in the above step (1) in which a plurality of wafers are placed on a workpiece processing sheet, a laser light irradiation device is used to irradiate the wafer with laser light through the workpiece processing sheet.

Specifically, using a laser light irradiation device (manufactured by KEYENCE Corporation, product name "MD-U1000C"), the wafer was irradiated with laser light having a wavelength of 355 nm through the workpiece processing sheet. This irradiation is performed by sequentially irradiating laser spots in a circle to the center of the wafer. At this time, the diameter of the laser spot was 25 μm, and the inner diameter of the ring formed as the trajectory of irradiation was 65 μm. As other irradiation conditions, frequency: 40 kHz, scanning speed: 500 mm/s, irradiation amount: 50 μJ/shot. In addition, irradiation was performed by selecting 100 wafers (total number of 10 vertically x 10 horizontally) from among a plurality of wafers.

(3) Confirmation of foaming and wafer separation For the workpiece processing sheet and the wafer subjected to the above irradiation, it was confirmed whether there is bubble generation at the interface between the base material and the interface ablation layer in the workpiece processing sheet, and whether there is detachment of the wafer from the workpiece processing sheet, according to the following criteria, Evaluation of suitability for laser ablation. The results are shown in Table 1. ◎...Bubbles occurred at the positions of all 100 wafers, and all 100 wafers were detached. ◯...The number of wafers in which bubbles occurred and detachment occurred was 80 or more and less than 100. ×...The number of wafers in which bubbles occurred and detachment occurred was less than 80 pieces.

In addition, details such as the abbreviations described in Table 1 are as follows. IrugacureOXE02: Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(0-acetyloxime) (manufactured by BASF Corporation , product name "IrugacureOXE02") Omnirad379: 2-Dimethylamino-2-(4-methylbenzyl)-1-(4-morpholino-phenyl)butan-1-one (manufactured by IGM Resins, product name "Omnirad379 」) Omnirad651: 2,2-dimethoxy-1,2-diphenylethane-1-one (manufactured by IGM Resins, product name "Omnirad651")

[Table 1] Photopolymerization initiator UV absorbance Adhesion (mN/25mm) Laser peeling suitability type Content (parts by mass) Before UV exposure after UV exposure Example 1 Irugacure OXE02 4 2.40 2300 30 ○ Example 2 Irugacure OXE02 8 3.36 2200 30 ◎ Example 3 Omnirad 379 20 3.21 2100 30 ◎ Comparative example 1 - - 0.10 2200 2200 x Comparative example 2 Omnirad 651 20 1.08 1700 30 x Comparative example 3 Irugacure OXE02 0.5 0.44 2200 30 x

It can be clearly seen from Table 1 that the workpiece processing sheets manufactured in the examples have excellent suitability for laser stripping. [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: Interface ablation layer 12: Substrate 13: Reaction area 2,2': small piece of workpiece 3: object 4: laser light 5: foaming 6: Laser light irradiation point

[ Fig. 1 ] is a cross-sectional view of a workpiece processing sheet according to an embodiment of the present invention. [ Fig. 2] 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. [FIG. 3] It is a cross-sectional view explaining the state of the bubble and reaction area which generate|occur|produce by irradiation of laser light.

1: Workpiece handling sheet

11: Interface ablation layer

12: Substrate

Claims (16)

A workpiece processing chip, in order to have: A substrate, and a workpiece treatment sheet laminated on one side of the above-mentioned substrate, which can be used to maintain a small piece of workpiece and perform an interface ablation layer by irradiation of laser light, is characterized in that: The above-mentioned interface ablation layer contains a photopolymerization initiator, The absorbance of light with a wavelength of 355 nm of the workpiece processing sheet is 1.5 or more. The workpiece processing sheet according to claim 1, wherein the photopolymerization initiator has an absorption peak in a wavelength range from 200 nm to 400 nm. The workpiece processing sheet according to claim 1, wherein the interface ablation layer is an adhesive layer. The workpiece processing sheet according to claim 3, wherein the adhesive constituting the adhesive layer is an active energy ray-curable adhesive. The workpiece processing sheet according to claim 3, wherein the adhesive constituting the adhesive layer is an acrylic adhesive. The workpiece processing sheet according to claim 1, wherein the laser light has a wavelength in the ultraviolet region. The workpiece processing sheet according to claim 1, wherein when the interface ablation layer causes interface ablation to occur, bubbles are formed at the position where the interface ablation occurs. The workpiece processing sheet according to claim 1, which is used to locally cause interface ablation on the above-mentioned interface ablation layer to maintain in the above-mentioned interface ablation layer opposite to the above-mentioned base material. Any one of the plurality of workpiece small pieces on the surface is selectively separated from the interface ablation layer. The workpiece processing sheet according to claim 8, wherein the workpiece small pieces are obtained by individualizing the workpiece held on the surface of the interface ablation layer opposite to the substrate. The workpiece processing chip according to claim 8, wherein the workpiece chip is at least one selected from a semiconductor device and a semiconductor device. The workpiece processing sheet as claimed in claim 8, wherein the workpiece chip is a light emitting diode selected from mini light emitting diodes and micro light emitting diodes. A device manufacturing method, characterized in that: Prepare a workpiece treatment sheet having a base material and an interface ablation layer containing a photopolymerization initiator laminated on one side of the base material, the absorbance of light having a wavelength of 355 nm being 1.5 or more, and on the side of the interface ablation layer A preparation step for a laminate formed by maintaining a plurality of workpiece small pieces on the surface; A step of arranging the laminated body so as to face a surface of the laminated body on the workpiece small piece side with respect to an object capable of holding the workpiece small piece; and Laser light is irradiated to a position in the interface ablation layer of the above-mentioned laminate body where at least one of the workpiece small pieces is attached, and interface ablation occurs in the above-mentioned irradiated position in the interface ablation layer, A separating step of separating the workpiece small piece existing at the position where the interface ablation occurs from the workpiece processing piece, and placing the workpiece small piece on the object. The device manufacturing method according to claim 12, wherein, in the preparation step, the workpiece maintained on the surface of the interface ablation layer opposite to the substrate is singulated on the surface , to obtain the above workpiece small pieces. The device manufacturing method according to claim 12, wherein the workpiece chip is at least one selected from a semiconductor device and a semiconductor device. The device manufacturing method according to claim 12, wherein a light-emitting device having a plurality of the above-mentioned light-emitting diodes is manufactured using a light-emitting diode selected from among miniature light-emitting diodes and micro-light-emitting diodes as the workpiece chip . The device manufacturing method according to claim 15, wherein the light emitting device is a display.

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