JP2009164501A - Method for manufacturing semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor element which can well perform a pickup process, which is the following process, while performing a water jet laser dicing with good dicing grade. <P>SOLUTION: In the method for manufacturing the semiconductor element, one surface of a cut body is stuck on an adhesive sheet for water jet laser dicing which is made by laminating an adhesive layer on a base film having a punched hole, and the water jet laser dicing is performed. The other side of the diced cut body is stuck and transferred on a pickup tape which is made by laminating the adhesive layer on the base film having no punched hole. Thereafter, the cut body is provided to the pickup process. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a semiconductor device, and more specifically, a method for manufacturing a semiconductor device to be subjected to a pickup process after water jet laser dicing a workpiece such as a semiconductor wafer and / or a semiconductor-related material.

  Conventionally, semiconductor wafers and semiconductor-related materials have been cut using a rotating blade and separated into chips and IC components. In this dicing process, usually, the semiconductor wafer or the like is bonded to an adhesive sheet in order to fix it, and the wafer or the like is cut into chips and then peeled off from the adhesive sheet by a pickup.

  However, in the conventional method, die fly may occur due to physical stress by the rotating blade, and defects such as cracking and chipping occur, and the quality of these chips and the like deteriorates, and the productivity of this cutting method is reduced. There was a problem of lowering. In particular, due to the recent demand for downsizing and thinning of electronic devices, these are more serious problems.

Therefore, as an alternative to cutting technology for semiconductor wafers using a rotating blade, a dicing method using a laser beam, particularly using a laser beam guided by a liquid jet, cutting, drilling, welding, marking and peeling. A material processing method based on the above has been proposed (for example, Patent Document 1).
In this method, since the wafer or the like is only exposed to the water flow from above, die fly or the like due to physical stress caused by the rotating blade can be prevented.

Moreover, in the cutting method using this laser technology, there is a problem that chips and the like are easily peeled off from the adhesive sheet for fixing them due to the use of water flow. A water-permeable adhesive sheet that can be suitably used has been proposed (for example, Patent Document 2).
WO95 / 32834 JP 2001-316648 A

  Usually, the separated semiconductor element is subjected to a pickup / die bonding process. In this step, generally, the semiconductor element is pushed up and picked up by a needle from below the fixing adhesive sheet.

  However, when using a laser beam as described above, cutting is performed using a water-permeable special adhesive sheet. The base film of this pressure-sensitive adhesive sheet is provided with perforations, thereby ensuring liquid permeability. Therefore, in the pick-up process, the pushed-up needle may directly collide with the adhesive from the perforation of the base film, causing the adhesive to adhere firmly to the semiconductor element and leave a residue after the pick-up. As a result, the semiconductor element is contaminated and the semiconductor element is destroyed due to the adhesive residue, the reliability is lowered, and the manufacturing yield of the semiconductor element is significantly reduced. Further, as the number of pick-ups is increased, adhesive residue is accumulated on the needle, which causes a reduction in production efficiency such as cleaning of the needle.

  Furthermore, at the time of pick-up, the vicinity of the push-up needle is adsorbed under reduced pressure from the back surface of the pressure-sensitive adhesive sheet to fix the pressure-sensitive adhesive sheet or to follow the needle, thereby making it easy to pick up, but provided on the base film. Due to the perforation, there is a problem that the vacuum suction on the needle side breaks through, the adhesive sheet cannot be fixed, pickup failure occurs, and production efficiency is lowered.

  The present invention has been made in view of the above problems, and provides a method for manufacturing a semiconductor device capable of satisfactorily performing the next pickup process while performing water jet laser dicing with good dicing quality. Objective.

In the method for producing a semiconductor element of the present invention, one surface of an object to be cut is attached to an adhesive sheet for water jet laser dicing in which an adhesive layer is laminated on a base film having perforations, and water jet laser dicing is performed.
The other surface of the diced object to be cut is pasted and transferred to a pickup tape in which an adhesive layer is laminated on a base film having no perforations,
Thereafter, the object to be cut is subjected to a pickup process.

In this method of manufacturing a semiconductor element, it is preferable that the pickup process is performed by a needle push-up type.
Moreover, it is preferable that the pressure-sensitive adhesive sheet for water jet laser dicing has a mesh structure or is formed of a base film made of a nonwoven fabric.
Further, the pickup tape is preferably formed of a base film having a thickness of 10 μm or more and 300 μm or less, or a tensile Young's modulus of 30 MPa or more and 5000 MPa or less.

  According to the method for manufacturing a semiconductor element of the present invention, since the pick-up can be performed without directly touching the base film having the perforations, adhesion of the adhesive to the needle, accumulation can be avoided, Contamination of the semiconductor element, cleaning of the needle, etc. can be minimized. Further, since the substrate film having perforations is not directly sucked under reduced pressure, the pickup can be performed without causing a pickup failure or the like. Thereby, it becomes possible to improve the manufacturing yield of the semiconductor element.

  In the method for producing a semiconductor element of the present invention, first, the object to be cut is attached to a water jet laser dicing adhesive sheet (hereinafter, simply referred to as “adhesive sheet”) and diced.

  The object to be cut in the present invention may be any material as long as it can finally become a semiconductor element. Usually refers to semiconductor wafers and semiconductor-related materials. The latter includes, for example, BGA packages, printed circuits, ceramic plates, glass components for liquid crystal devices, sheet materials, circuit boards, glass substrates, ceramic substrates, metal substrates, semiconductor laser light emitting / receiving element substrates, MEMS substrates, or semiconductor packages. Etc.

The pressure-sensitive adhesive sheet of the present invention is suitably used for water jet laser dicing, and mainly comprises a base film and a pressure-sensitive adhesive layer disposed thereon.
Here, the water jet laser dicing is dicing using a laser beam guided by a liquid flow (usually a water flow), and the water jet laser dicing adhesive sheet is used for the above-mentioned dicing and at the time of dicing. This liquid flow, for example, when a liquid flow of a predetermined pressure or higher is applied directly or indirectly to the base film from the pressure-sensitive adhesive layer side, can be released from one surface side of the pressure-sensitive adhesive sheet to the other surface side. Refers to an adhesive sheet. The predetermined pressure at this time can usually be about several MPa or more.

The base film has perforations. This perforation is preferably a hole penetrating in the thickness direction, but may be a hole that is connected in the thickness direction as a result of a plurality of holes being connected. In particular, the holes in the base film are preferably openings when the base film has a mesh structure, or are made of unemployed cloth.
The size of the perforations is not particularly limited as long as it allows water to pass through, and can be appropriately adjusted depending on the pressure, flow rate, and the like of the liquid flow of the dicing apparatus to be used.
The material of the base film is not particularly limited, and examples thereof include synthetic resins usually used in the field, for example, polyolefins such as polyethylene and polypropylene, and polymers such as polyester. In particular, the base film preferably has a tensile Young's modulus of about 30 to 5000 MPa. Thereby, in a pick-up process, an adhesive sheet and the pick-up tape mentioned later can be extended, and it becomes possible to pick up a to-be-cut body easily from an adhesive sheet. The base film may have a single layer or a multilayer structure of two or more layers.

The pressure-sensitive adhesive layer is constituted by a pressure-sensitive adhesive layer applied to one surface of the base film. This pressure-sensitive adhesive may be any of a pressure-sensitive type, a heat-sensitive type, and a photosensitive type, but is preferably a type of pressure-sensitive adhesive that is cured by irradiation with energy rays. Thereby, the peelability from the workpiece can be easily performed.
As energy rays, for example, those having various wavelengths such as ultraviolet rays, visible rays, infrared rays and the like can be used. However, the laser beam used for dicing is an energy ray having an oscillation wavelength of 400 nm or less, for example, an oscillation wavelength of 248 nm. KrF excimer laser, 308 nm XeCI excimer laser, YAG laser third harmonic (355 nm), fourth harmonic (266 nm), or energy rays with an oscillation wavelength of 400 nm or more, for example, ultraviolet region via multiphoton absorption process And a pulse width of 1 × 10 ⁻⁹ seconds (0.000000001 seconds) using a titanium sapphire laser or the like in the vicinity of a wavelength of 750 to 800 nm, which can be cut with a width of 20 μm or less by multiphoton absorption ablation. ) Use because it is the following laser etc. It is preferable to use a pressure sensitive adhesive not cured by the irradiation of laser beam Ishingu device.

As a material for forming the pressure-sensitive adhesive layer, any of known pressure-sensitive adhesives including a rubber polymer, a (meth) acrylic polymer, and the like can be used.
Examples of the rubber-based polymer may include natural rubber (for example, polyisoprene) and synthetic rubber (for example, styrene-butadiene rubber, polybutadiene-based, butadiene-acrylonitrile-based, chloroprene-based rubber, etc.).

  Examples of the monomer component constituting the (meth) acrylic polymer include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a t-butyl group, an isobutyl group, an amyl group, an isoamyl group, and a hexyl group. Group, heptyl group, cyclohexyl group, 2-ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, lauryl group, tridecyl group, tetradecyl group, stearyl group, octadecyl group and dodecyl group Examples thereof include alkyl acrylate or alkyl methacrylate having a linear or branched alkyl group having 30 or less carbon atoms, preferably 4 to 18 carbon atoms. These alkyl (meth) acrylates may be used alone or in combination of two or more.

  Examples of other monomer components include acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid and other carboxyl group-containing monomers, maleic anhydride Acid anhydride monomers such as acid and itaconic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxy (meth) acrylate Hydroxyl group-containing monoesters such as hexyl, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate and (4-hydroxymethylcyclohexyl) methyl (meth) acrylate -Sulfones such as styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate and (meth) acryloyloxynaphthalene sulfonic acid Acid group-containing monomers, phosphate group-containing monomers such as 2-hydroxyethylacryloyl phosphate, (meth) acrylamide, (meth) acrylic acid N-hydroxymethylamide, (meth) acrylic acid alkylaminoalkyl esters (for example, dimethylaminoethyl Methacrylate, t-butylaminoethyl methacrylate, etc.), N-vinylpyrrolidone, acryloylmorpholine, vinyl acetate, styrene, acrylonitrile and the like. These monomer components may be used alone or in combination of two or more.

Moreover, you may use a polyfunctional monomer arbitrarily for the purpose of bridge | crosslinking of a (meth) acrylic-type polymer. Examples of polyfunctional monomers include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and pentaerythritol di (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Examples include epoxy (meth) acrylate, polyester (meth) acrylate, and urethane (meth) acrylate. These polyfunctional monomers may be used alone or in combination of two or more.
The amount of the polyfunctional monomer used is preferably 30% by weight or less, more preferably 20% by weight or less of the total monomer components from the viewpoint of adhesive properties and the like.

Furthermore, a monomer and / or oligomer having an energy ray-curable functional group such as a carbon-carbon double bond may be used.
Examples of the monomer / oligomer include urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, Examples include dipentaerythritol hexa (meth) acrylate and 1,4-butylene glycol di (meth) acrylate. These may be used alone or in combination of two or more.
These blending amounts are not particularly limited, but in consideration of tackiness, it is about 5 to 500 parts by weight with respect to 100 parts by weight of the base polymer such as (meth) acrylic polymer constituting the pressure-sensitive adhesive. It is preferable that it is about 70 to 150 parts by weight.

Moreover, when comprising a photosensitive adhesive, it is preferable to use a photoinitiator.
Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α-methylacetophenone, methoxyacetophenone, 2,2-dimethoxy-2- Acetophenone compounds such as phenylacetophenone, 2,2-diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1, benzoin ethyl ether, benzoin Benzoin ether compounds such as isopropyl ether and anisoin methyl ether, α-ketol compounds such as 2-methyl-2-hydroxypropylphenone, ketal compounds such as benzyldimethyl ketal, 2-naphthalenesulfonyl chloride Aromatic sulfonyl chloride compounds such as Lido, photoactive oxime compounds such as 1-phenone-1,1-propanedione-2- (o-ethoxycarbonyl) oxime, benzophenone, benzoylbenzoic acid, 3,3′-dimethyl Benzophenone compounds such as -4-methoxybenzophenone, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2 Thioxanthone compounds such as 1,4-diethylthioxanthone and 2,4-diisopropylthioxanthone, camphorquinone, halogenated ketone, acyl phosphinoxide and acyl phosphonate. These may be used alone or in combination of two or more.
The blending amount of the photopolymerization initiator is preferably about 0.1 to 10 parts by weight, more preferably about 0.5 to 5 parts by weight with respect to 100 parts by weight of the base polymer constituting the pressure-sensitive adhesive. .

Furthermore, in order to increase the weight average molecular weight of the base polymer, a crosslinking agent may optionally be added.
Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, aziridine compounds, melamine resins, urea resins, anhydrous compounds, polyamines, and carboxyl group-containing polymers. These may be used alone or in combination of two or more. In the case of using a crosslinking agent, the amount used thereof is generally about 0.01 to 5 parts by weight with respect to 100 parts by weight of the base polymer, considering that the peeling adhesion does not decrease too much. preferable.

  In addition to the above components, additives such as conventionally known tackifiers, anti-aging agents, fillers, anti-aging agents, and coloring agents can be optionally added.

  For the preparation of the (meth) acrylic polymer, for example, a known method such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, or a suspension polymerization method is applied to one or more monomers or a mixture thereof. Can be done. Of these, the solution polymerization method is preferable. Examples of the solvent used here include polar solvents such as ethyl acetate and toluene. The solution concentration is usually about 20 to 80% by weight.

In preparing the polymer, a polymerization initiator may be used. Examples of the polymerization initiator include peroxides such as hydrogen peroxide, benzoyl peroxide, and t-butyl peroxide. Although it is desirable to use it alone, it may be used as a redox polymerization initiator in combination with a reducing agent.
Examples of the reducing agent include ionized salts such as sulfite, bisulfite, iron, copper, and cobalt salts, amines such as triethanolamine, and reducing sugars such as aldose and ketose. 2,2′-azobis-2-methylpropioaminate, 2,2′-azobis-2,4-dimethylvaleronitrile, 2,2′-azobis-N, N′-dimethyleneisobutylamidine acid An azo compound such as a salt, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2-methyl-N- (2-hydroxyethyl) propionamide may be used. These may be used alone or in combination of two or more.

The reaction temperature is usually about 50 to 85 ° C., and the reaction time is about 1 to 8 hours.
In particular, the (meth) acrylic polymer preferably has a low content of a low molecular weight substance from the viewpoint of preventing contamination of the object to be cut, and the weight average molecular weight of the (meth) acrylic polymer is 300,000 or more, Furthermore, about 80-3 million is preferable.

  The thickness of the pressure-sensitive adhesive layer is not particularly limited, but is preferably set to a thickness that allows the liquid flow to pass through the dicing tape during dicing.

The pressure-sensitive adhesive sheet used in the present invention can be formed by a method for producing a tape known in the art.
For example, first, a base film is prepared.
Subsequently, an adhesive is laminated | stacked on a base film. In this case, the substrate film may be coated directly, or a transfer coating method in which an adhesive is coated on a process material coated with a release agent, dried, and then laminated on the substrate film is used. The pressure-sensitive adhesive may be roll-laminated on the base film.
These coatings can utilize various methods such as reverse roll coating, gravure coating, curtain spray coating, die coating, extrusion and other industrially applied coating methods.
The prepared base film may have perforations in the state of the base film, or may be formed after coating the base film with an adhesive.

Affixing the object to be cut to the pressure-sensitive adhesive sheet is performed by affixing the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet on one surface of the object to be cut, such as a semiconductor wafer, and in accordance with conditions, methods, etc. that are normally performed in this field. Can do.
The dicing may be performed using any apparatus as long as it can be performed using a laser beam guided by a liquid flow. For example, an apparatus using a technique described in WO95 / 32834 can be used.

Next, a pickup tape is attached to the other surface of the diced object to be cut and transferred.
The attachment to the pickup tape here is performed by attaching an adhesive layer of the pickup tape to the surface opposite to the surface to which the adhesive sheet of the diced object to be cut is attached. That is, the object to be cut is pasted so as to be sandwiched between the adhesive sheet and the pickup tape.
The method of pasting is not particularly limited, but is allowed to stand on the table with the surface opposite to the surface on which the adhesive sheet of the diced object to be cut is pasted, and the pickup tape is pasted with a roller. The attaching method is simple. Conditions such as pressure, roller rotation speed, and temperature at this time can be adjusted to such an extent that the object to be cut does not break and the pickup tape adheres to the object to be cut.

The pickup tape mainly includes a base film and an adhesive layer disposed thereon.
A conventionally well-known film which does not have perforation can be used for a base film. In particular, a base film having a tensile Young's modulus of about 30 to 5000 MPa is preferable. The thickness is not particularly limited. For example, in order to propagate the needle push-up stress and facilitate pickup, the thickness is 10 to 300 μm, preferably 30 to 200 μm. The base film may have a single layer or a multilayer structure of two or more layers.

The pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer may be any of pressure-sensitive type, heat-sensitive type, and photosensitive type.
Examples of the material for forming the pressure-sensitive adhesive layer, the method for forming the pressure-sensitive adhesive layer, and the like are the same as those for the pressure-sensitive adhesive sheet described above.

The thickness of an adhesive layer can be suitably adjusted in the range which does not peel from the base film of an adhesive sheet. For example, it is about 30-500 micrometers, More preferably, it is about 30-200 micrometers.
Moreover, although the elasticity modulus of an adhesive layer can be adjusted suitably, for example, about 0.1-2 MPa is preferable.

Here, “transfer” means to transfer the form of the object to be cut after the one surface of the object to be cut is attached to the adhesive sheet and diced to the pickup tape as it is. This means that the other surface is attached to the pickup tape, and then the adhesive sheet is peeled off.
For example, as shown to Fig.1 (a), the adhesive sheet 11 which has the perforation 11a in a base material is affixed on a to-be-cut body, and an adhesive sheet water jet laser dicing is performed.
Thereafter, as shown in FIG. 1B, the other surface of the semiconductor chip 10 which is the diced object to be cut is attached to the pickup tape 12 which does not have perforations in the base material, and the adhesive sheet 11 is peeled off. As a result, the semiconductor chip 10 is transferred to the pickup tape 12.

The pressure-sensitive adhesive sheet is preferably peeled after the pressure-sensitive adhesive sheet is lightly peeled. For example, when the pressure-sensitive adhesive sheet is formed of a photosensitive type or heat-sensitive type pressure-sensitive adhesive, light peeling can be performed by performing light irradiation and / or heating.
The light release may be performed before or after the pickup tape is attached. If an external force is applied to the pick-up tape after light release, the object to be cut may be peeled off unexpectedly. preferable.
Further, after the other surface of the diced object to be cut is pasted and transferred to a pickup tape in which an adhesive layer is laminated on a base film having no perforations, that is, after the adhesive sheet is peeled off, the pickup is performed. It is preferable to lightly peel the tape. Light release can be performed in the same manner as described above.

Thereafter, the object to be cut is subjected to a pickup process.
A pick-up process is not specifically limited, The thing normally utilized in the said field | area can be utilized. Among these, those utilizing a needle push-up type as described below are preferable.

  For example, as shown in FIG. 1B, the other surface of the semiconductor chip 10 that is a diced object to be cut is attached to a pickup tape 12 that does not have perforations in the base material (semiconductor chip 10). The adhesive sheet 11 that has been attached to one surface has already been peeled off), and the semiconductor chip 10 is pushed up in the direction of the arrow by the needle 13 from the pickup tape 12 side. At this time, since the semiconductor chip 10 has high rigidity, if the adhesive force of the adhesive sheet 11 is sufficiently reduced, the semiconductor chip 10 is partially peeled off by the needle 13.

  After the needle 13 is pushed up, the semiconductor chip 10 is adsorbed by the collet 14 from above the semiconductor chip 10 as shown in FIG. As the collet 14 is pulled up in the direction of the arrow, the adhesive sheet 11 is naturally peeled from the semiconductor chip 10.

Examples of the method for manufacturing a semiconductor device of the present invention will be described in detail below.
Example (Preparation of base film for water jet laser dicing)
A mesh film having a density of 200 × 200 fibers / inch, a void area of 32%, and a thickness of 90 μm was formed using polyethylene terephthalate fibers having a fiber diameter of 55 μm. A material obtained by subjecting this mesh film to corona treatment was used as a base film.
(Adhesive sheet for water jet laser dicing)
40 parts by weight of methyl acrylate, 35 parts by weight of 2-methoxyethyl acrylate, 20 parts by weight of acryloylmorpholine, and 5 parts by weight of acrylic acid were copolymerized in a conventional manner in ethyl acetate. As a result, a solution containing an acrylic copolymer having a weight average molecular weight of 600,000 was obtained.
Next, 100 parts by weight of an ultraviolet curable oligomer (viscosity at 25 ° C. of 10 Pa · sec) obtained by reacting a solution containing an acrylic copolymer with pentaerythritol triacrylate and diisocyanate, a photopolymerization initiator ( Add 3 parts by weight of the product name “Irgacure 651”, manufactured by Ciba Specialty Chemicals Co., Ltd.) and 2 parts by weight of a polyisocyanate compound (trade name “Coronate L”, manufactured by Nippon Polyurethane Co., Ltd.). An agent solution was obtained.
The obtained ultraviolet curable pressure-sensitive adhesive solution was applied onto the above base film so that the pressure-sensitive adhesive layer had a thickness of 15 μm to obtain a pressure-sensitive adhesive sheet.

(Dicing conditions)
A silicon wafer ground to a thickness of 100 μm was pasted on the obtained adhesive sheet for dicing, and diced under the following conditions.
Laser wavelength: 532 nm
Dicing speed: 50mm / s
Laser diameter: 50 μm
Water jet pressure: 8MPa
Chip size: 5mm x 5mm
Wafer size: 13.7 cm (5 inches)

(Preparation of base material for pickup tape)
A film (Young's modulus 150 MPa) made of linear low-density polyethylene having a thickness of 70 μm was used as the base film. One side of this film was corona treated.

(Preparation of pickup tape)
50 parts by weight of methyl acrylate, 45 parts by weight of 2-ethylhexyl acrylate, and 5 parts by weight of acrylic acid were copolymerized in ethyl acetate by a conventional method. As a result, a solution containing an acrylic copolymer having a weight average molecular weight of 800,000 was obtained. Next, 100 parts by weight of an ultraviolet curable oligomer (viscosity at 25 ° C. of 10 Pa · sec) obtained by reacting a solution containing an acrylic copolymer with pentaerythritol triacrylate and diisocyanate, a photopolymerization initiator ( Add 3 parts by weight of the product name “Irgacure 651”, manufactured by Ciba Specialty Chemicals Co., Ltd.) and 2 parts by weight of a polyisocyanate compound (trade name “Coronate L”, manufactured by Nippon Polyurethane Co., Ltd.). An agent solution was obtained.
The obtained ultraviolet curable pressure-sensitive adhesive solution was applied on the above base film so that the thickness of the pressure-sensitive adhesive layer was 10 μm to obtain a pressure-sensitive adhesive sheet.

(Transfer of semiconductor elements to pickup tape)
Water jet laser dicing is performed by irradiating ultraviolet rays for 20 seconds at an illuminance of 30 mW / cm ² using a high-pressure mercury lamp from the back of the workpiece after dicing in a nitrogen atmosphere, that is, the base film side of the water jet laser dicing adhesive sheet. The pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet was cured and lightly peeled.
Next, a pickup tape was attached to the surface of the semiconductor element with a roller having a diameter of 75 mm, a width of 200 mm, and a weight of 2 kg at a speed of 10 mm / s, and the water jet laser dicing adhesive sheet was peeled off.

(UV irradiation)
From the back of the pickup tape, using a high-pressure mercury lamp, irradiation with ultraviolet rays was performed for 20 seconds at an illuminance of 30 mW / cm ² to provide the pickup process.

Comparative Example From the back surface of the workpiece after dicing, the same ultraviolet ray irradiation as in the example was performed and used for the pickup.

(Pickup test)
50 arbitrary semiconductor chips in Examples and Comparative Examples were picked up under the following conditions, and the number of successes was counted. The results are shown in Table 1.
A case where everything was successful was judged good, and a case where there was unsuccessful was regarded as bad.
Moreover, the chip | tip which picked up successfully was observed with the microscope, and the presence or absence of adhesion of an adhesive was confirmed. The case where adhesion of an adhesive was not recognized was good, and the case where it was recognized was regarded as poor.

(Pickup conditions)
Die Bonder: Shinkawa SPA-300
Number of pins: 4 Pin spacing: 3.5 x 3.5 mm
Pin tip curvature: 0.250mm
Pin push-up amount: 0.80mm
Adsorption holding time: 0.2 seconds Extraction amount: 1 mm

As is clear from Table 1, by transferring the semiconductor element from the water jet laser dicing adhesive sheet to the pickup tape, the pickup property is improved and adhesion of the adhesive to the back surface of the semiconductor chip can be suppressed.
On the other hand, as shown in the comparative example, when the pickup tape was not attached, many scratches or chip cracks due to needles were observed on the back surface of the chip.

  The method for manufacturing a semiconductor device of the present invention is an object that can be subjected to water jet laser dicing, that is, a semiconductor-related material (for example, a semiconductor wafer, a BGA package, a printed circuit, a ceramic plate, a glass component for a liquid crystal device, a sheet material). , Circuit boards, glass substrates, ceramic substrates, metal substrates, semiconductor laser light emitting / receiving element substrates, MEMS substrates, semiconductor packages, etc.), etc., and a wide range of materials.

It is a schematic plan view which shows the manufacturing method of the semiconductor element of this invention.

Explanation of symbols

10 Semiconductor chip (object to be cut)
11 Adhesive Sheet 11a Perforation 12 Pickup Tape 13 Needle 14 Collet

Claims (6)

One surface of the object to be cut is attached to an adhesive sheet for water jet laser dicing in which an adhesive layer is laminated on a base film having perforations, and water jet laser dicing is performed.
The other surface of the diced object to be cut is pasted and transferred to a pickup tape in which an adhesive layer is laminated on a base film having no perforations,
Then, the said to-be-cut body is used for a pick-up process, The manufacturing method of the semiconductor element characterized by the above-mentioned.   The method of manufacturing a semiconductor element according to claim 1, wherein the pickup process is performed by a needle push-up type.   The semiconductor element manufacturing method according to claim 1 or 2, wherein the water jet laser dicing adhesive sheet is formed of a base film having a mesh structure.   The semiconductor element manufacturing method according to claim 1 or 2, wherein the water jet laser dicing pressure-sensitive adhesive sheet is formed of a base film made of a nonwoven fabric.   The semiconductor element manufacturing method according to claim 1, wherein the pickup tape is formed of a base film having a thickness of 10 μm or more and 300 μm or less.   The semiconductor element manufacturing method according to any one of claims 1 to 5, wherein the pickup tape is formed of a base film having a tensile Young's modulus of 30 MPa or more and 5000 MPa or less.

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