JP2014003274A - Method for manufacturing semiconductor device and underfill material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device, in which there is no particular limit in a formation material of an underfill material and positioning for mounting a semiconductor element is simple.SOLUTION: A method for manufacturing a semiconductor device of present invention is a method of manufacturing a semiconductor device including an adherend, a semiconductor element electrically connected with the adherend and an underfill material filled in a space between the adherend and the semiconductor element, and comprises: a position matching process of irradiating an exposed surface of an underfill material stuck to a circuit surface of the semiconductor element and having total light transmittance of 50% or greater with oblique beams and matching relative positions of the semiconductor element and the adherend with respective scheduled connection positions; and a connection process of electrically connecting the semiconductor element and the adherend via a connection material while filling a space between the adherend and the semiconductor element with the underfill material.

Description

  The present invention relates to a semiconductor device manufacturing method and an underfill material.

  In recent years, the demand for high-density packaging due to the miniaturization and thinning of electronic devices has increased rapidly. For this reason, the surface mount type suitable for high-density mounting is the mainstream of the semiconductor package instead of the conventional pin insertion type. In this surface mount type, the lead is soldered directly to a printed circuit board or the like. As a heating method, the entire package is heated and mounted by infrared reflow, vapor phase reflow, solder dipping, or the like.

  After the surface mounting, the space between the semiconductor element and the substrate is filled with a sealing resin in order to protect the surface of the semiconductor element and to ensure the connection reliability between the semiconductor element and the substrate. As such a sealing resin, although a liquid sealing resin is widely used, it is difficult to adjust the injection position and the injection amount with the liquid sealing resin. Therefore, a technique for filling a space between a semiconductor element and a substrate using a sheet-shaped sealing resin has also been proposed (Patent Document 1).

  In general, as a process using a sheet-like sealing resin (underfill material), after bonding an underfill material to a semiconductor wafer, the semiconductor wafer is diced to form a semiconductor element, and the semiconductor element is covered. A procedure is employed in which a space between an adherend such as a substrate and the semiconductor element is filled with an underfill material integrated with the semiconductor element while being connected to the adherend and mounted.

  In the process as described above, the space between the adherend and the semiconductor element can be easily filled. On the other hand, with the narrowing of the circuit width and the distance between terminals in the semiconductor element, if even a slight deviation occurs when matching to the connection position at the time of mounting, it leads to damage of the semiconductor element or bonding failure at the time of mounting, As a result, the yield of semiconductor device manufacturing may be reduced.

  With regard to positioning during mounting, the sheet-like underfill material is pre-laminated on the semiconductor element, so the underfill material is used for alignment provided to the semiconductor element when aligning the semiconductor element and the substrate when mounting the semiconductor element. Transparency that can recognize the mark is required. However, since the underfill material generally contains an additive such as a silica filler to improve its characteristics, the permeability of the underfill material is reduced, and the semiconductor element and the substrate are mounted at the time of mounting the semiconductor element. It may be difficult to perform the alignment.

  Combining a first curable transparent resin composition containing a colloidal silica dispersion and an epoxy resin and a second curable flux composition containing a curable flux composition as an underfill composition for solving these problems. Thus, a technique for improving the transparency of the underfill material has been proposed (Patent Document 2).

Patent No. 4438973 Special table 2007-515524 gazette

  However, although the transparency of the underfill material is improved by the above technique, for this purpose, a specific component such as a functionalized colloidal silica dispersion or a cycloaliphatic epoxy monomer, which is a nano-sized filler having a predetermined functional group, is used. It is necessary to use it, and the materials that can be used for the underfill material are limited.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a semiconductor device in which there is no particular limitation on the material for forming the underfill material, and positioning for mounting semiconductor elements is simple, and an underfill material suitable for the manufacturing method. And

  The inventors of the present application have conducted intensive studies and found that the object can be achieved by adopting the following configuration, and have completed the present invention.

That is, the present invention provides a semiconductor device comprising an adherend, a semiconductor element electrically connected to the adherend, and an underfill material that fills a space between the adherend and the semiconductor element. A manufacturing method of
The exposed surface of the underfill material having a total light transmittance of 50% or more bonded to the circuit surface of the semiconductor element is irradiated with oblique light, and the relative position between the semiconductor element and the adherend is determined as the connection position of each other. A position aligning process for aligning with
A connecting step of electrically connecting the semiconductor element and the adherend through the connecting member while filling a space between the adherend and the semiconductor element with the underfill material.

  In this manufacturing method, even when the total light transmittance of the underfill material is reduced to about 50%, the position of the semiconductor element is accurately detected only by irradiating oblique light onto the exposed surface of the underfill material. be able to. As a result, it is possible to easily align the semiconductor element and the adherend to the planned connection position, and as a result, efficiently manufacture the semiconductor device without paying special consideration to the formation material of the underfill material. can do. In addition, the measuring method of a total light transmittance is based on description of an Example.

  In the manufacturing method, it is preferable to irradiate oblique light at an incident angle of 5 to 85 ° with respect to the exposed surface of the underfill material. By irradiating oblique light at such an incident angle, it is possible to prevent specular reflection light and improve the position detection accuracy of the semiconductor element, and to further improve the accuracy of matching to the planned connection position.

  In the manufacturing method, the oblique light preferably includes a wavelength of 400 to 550 nm. When the oblique light includes the specific wavelength, it exhibits good permeability even for an underfill material formed of a general material including an inorganic filler. Matching can be performed more easily.

  In the manufacturing method, it is preferable to irradiate the oblique light from two or more directions or all directions with respect to the exposed surface of the underfill material. By oblique light irradiation from multiple directions or all directions (all circumferential directions), the diffuse reflection from the semiconductor element can be increased to increase the accuracy of position detection, and the accuracy of alignment with the planned connection position with the adherend can be improved. It can be improved further.

  In the manufacturing method, even if the underfill material contains a general inorganic filler, it is possible to easily detect the position of the semiconductor element and match the expected connection position by oblique light irradiation.

  In the said manufacturing method, it is preferable that the average particle diameter of the said inorganic filler is 0.005-10 micrometers. When the average particle size of the inorganic filler is less than 0.005 μm, the particles are likely to aggregate and it may be difficult to form the underfill material. On the other hand, if the thickness exceeds 10 μm, the inorganic particles tend to bite into the joint between the underfill material and the adherend, and the reliability of the semiconductor device may be reduced.

  In the manufacturing method, the underfill material preferably includes a thermoplastic resin and a thermosetting resin. As a result, while maintaining the transparency of the underfill material, it provides the underfill material with a well-balanced flexibility, strength, and adhesion necessary to enhance the adhesion of the underfill material to the semiconductor wafer in the bonding process. can do.

The underfill material of the present invention is used to arrange in a space between the adherend and the semiconductor element in a semiconductor device in which a semiconductor element is mounted on the adherend,
An inorganic filler having a surface treatment and an average particle size of 0.1 μm or less;
A thermosetting resin;
A thermoplastic resin;
And a curing accelerating catalyst.

  Since the average particle size of the inorganic filler contained in the underfill material is 0.1 μm or less, it exhibits good transparency to general light used for detecting alignment marks and the like, and is attached to the semiconductor element. Positioning with the body can be performed accurately and easily. In addition, by applying surface treatment to the inorganic filler, the affinity with the organic component contained in the underfill material is increased and the dispersibility of the inorganic filler is also improved. As a result, the transparency of the underfill material is improved. Can be improved.

  In the underfill material, the surface treatment is preferably a treatment with a silane coupling agent. By surface treatment with a silane coupling agent, the dispersibility of the inorganic filler in the organic component of the underfill material, and thus the transparency of the underfill material can be further improved.

  In the underfill material, the inorganic filler is preferably a silica filler from the viewpoints of surface treatment ease and availability, ease of adjusting the elastic modulus of the underfill material, and the like.

  The content of the inorganic filler in the underfill material is preferably 70% by weight or less. By setting the content of the inorganic filler to 70% by weight or less, good transparency of the underfill material can be maintained.

It is a cross-sectional schematic diagram which shows the sealing sheet which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows the dicing position determination process which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows the position alignment process which concerns on one Embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on other embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on other embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on other embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on other embodiment of this invention. It is a cross-sectional schematic diagram which shows 1 process of the manufacturing process of the semiconductor device which concerns on other embodiment of this invention.

  The present invention provides a semiconductor device including an adherend, a semiconductor element electrically connected to the adherend, and an underfill material that fills a space between the adherend and the semiconductor element. A method of irradiating oblique light to an exposed surface of an underfill material having a total light transmittance of 50% or more bonded to a circuit surface of a semiconductor element, and determining a relative position between the semiconductor element and the adherend. A position aligning step for aligning with each other's planned connection positions, and filling the space between the adherend and the semiconductor element with the underfill material, the semiconductor element and the adherend through the connection member. A connecting step of electrically connecting.

  Further, the present invention is an underfill material disposed in a space between the adherend and the semiconductor element in a semiconductor device in which a semiconductor element is mounted on the adherend, and has an average particle size of 0.1. An inorganic filler having a size of 1 μm or less, a thermosetting resin, a thermoplastic resin, and a curing accelerating catalyst are included. Hereinafter, a first embodiment which is an embodiment of the present invention will be described.

<First Embodiment>
In the first embodiment, as a pre-process of the alignment process, the backside grinding of the semiconductor wafer is performed using a sealing tape including an underfill material laminated on the backside grinding tape, and then dicing on the dicing tape. The semiconductor element is picked up. As a representative process, a preparation process for preparing a sealing sheet comprising a back grinding tape and an underfill material having a total light transmittance of 50% or more laminated on the back grinding tape, connection of a semiconductor wafer A laminating step of bonding the circuit surface on which the member is formed and the underfill material of the sealing sheet, a grinding step of grinding the back surface of the semiconductor wafer, and peeling the semiconductor wafer together with the underfill material from the back surface grinding tape. Fixing the semiconductor wafer to the dicing tape, dicing the semiconductor wafer to form the semiconductor element with the underfill material, and peeling the semiconductor element with the underfill material from the dicing tape. A pick-up process is mentioned. Hereinafter, these pre-processes and processes after the position alignment process will be described.

[Preparation process]
In the preparation step, a sealing sheet including a back grinding tape and an underfill material having a total light transmittance of 50% or more laminated on the back grinding tape is prepared. As the support material for the sealing sheet, a base material, a tape for back surface grinding, a dicing tape, or the like can be suitably used. In this embodiment, a case where a back grinding tape is used will be described as an example.

(Sealing sheet)
As shown in FIG. 1, the sealing sheet 10 includes a back surface grinding tape 1 and an underfill material 2 laminated on the back surface grinding tape 1. As shown in FIG. 1, the underfill material 2 may be provided in a size sufficient for bonding to the semiconductor wafer 3 (see FIG. 2A), and is laminated on the entire surface of the back surface grinding tape 1. It may be.

(Back grinding tape)
The back grinding tape 1 includes a substrate 1a and an adhesive layer 1b laminated on the substrate 1a. In addition, the underfill material 2 is laminated | stacked on the adhesive layer 1b.

(Base material)
The base material 1 a is a strength matrix of the sealing sheet 10. For example, polyolefins such as low density polyethylene, linear polyethylene, medium density polyethylene, high density polyethylene, ultra low density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolyprolene, polybutene, polymethylpentene, ethylene-acetic acid Vinyl copolymer, ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester (random, alternating) copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, Polyester such as polyurethane, polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyetheretherketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide, polyphenylsulfur De, aramid (paper), glass, glass cloth, fluorine resin, polyvinyl chloride, polyvinylidene chloride, cellulose resin, silicone resin, metal (foil), paper, and the like. In the case where the pressure-sensitive adhesive layer 1b is of an ultraviolet curable type, the substrate 1a is preferably transparent to ultraviolet rays.

  Examples of the material for the substrate 1a include polymers such as a crosslinked body of the above resin. The plastic film may be used unstretched or may be uniaxially or biaxially stretched as necessary.

  The surface of the substrate 1a is chemically treated by conventional surface treatments such as chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, etc. in order to improve adhesion and retention with adjacent layers. Alternatively, a physical treatment or a coating treatment with a primer (for example, an adhesive substance described later) can be performed.

  As the base material 1a, the same kind or different kinds can be appropriately selected and used, and if necessary, a blend of several kinds can be used. In addition, in order to impart antistatic ability to the base material 1a, a conductive material vapor deposition layer having a thickness of about 30 to 500 mm made of metal, alloy, oxides thereof, or the like is provided on the base material 1a. be able to. Antistatic ability can also be imparted by adding an antistatic agent to the substrate. The substrate 1a may be a single layer or a multilayer of two or more.

  The thickness of the substrate 1a can be determined as appropriate, and is generally about 5 μm to 200 μm, preferably 35 μm to 120 μm.

  In addition, various additives (for example, a colorant, a filler, a plasticizer, an anti-aging agent, an antioxidant, a surfactant, a flame retardant, etc.) are added to the substrate 1a as long as the effects of the present invention are not impaired. May be included.

(Adhesive layer)
The pressure-sensitive adhesive used for forming the pressure-sensitive adhesive layer 1b firmly holds the semiconductor wafer via the underfill material during back surface grinding, and is used when the semiconductor wafer with the underfill material is transferred to a dicing tape after back surface grinding. There is no particular limitation as long as the semiconductor wafer with the fill material can be controlled to be peelable. For example, a general pressure-sensitive adhesive such as an acrylic pressure-sensitive adhesive or a rubber-based pressure-sensitive adhesive can be used. As the pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive having an acrylic polymer as a base polymer from the viewpoint of cleanability of an electronic component that is difficult to contaminate semiconductor wafers, glass, etc., with an organic solvent such as ultrapure water or alcohol. Is preferred.

  Examples of the acrylic polymer include those using an acrylic ester as a main monomer component. Examples of the acrylic ester include (meth) acrylic acid alkyl ester (for example, methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester, tridecyl ester, tetradecyl ester, hexadecyl ester , Octadecyl esters, eicosyl esters, etc., alkyl groups having 1 to 30 carbon atoms, especially 4 to 18 carbon linear or branched alkyl esters, etc.) and Meth) acrylic acid cycloalkyl esters (e.g., cyclopentyl ester, acrylic polymers such as one or more was used as a monomer component of the cyclohexyl ester etc.). In addition, (meth) acrylic acid ester means acrylic acid ester and / or methacrylic acid ester, and (meth) of the present invention has the same meaning.

  The acrylic polymer includes units corresponding to the other monomer components copolymerizable with the (meth) acrylic acid alkyl ester or cycloalkyl ester, if necessary, for the purpose of modifying cohesive force, heat resistance, and the like. You may go out. Examples of such monomer components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; maleic anhydride Acid anhydride monomers such as itaconic anhydride; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate Hydroxyl group-containing monomers such as 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate; The Sulfonic acid groups such as lensulfonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalenesulfonic acid Containing monomers; Phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate; acrylamide, acrylonitrile and the like. One or more of these copolymerizable monomer components can be used. The amount of these copolymerizable monomers used is preferably 40% by weight or less based on the total monomer components.

  Furthermore, since the acrylic polymer is crosslinked, a polyfunctional monomer or the like can be included as a monomer component for copolymerization as necessary. Examples of such polyfunctional monomers include hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, Pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, urethane (meth) Examples include acrylates. These polyfunctional monomers can also be used alone or in combination of two or more. The amount of the polyfunctional monomer used is preferably 30% by weight or less of the total monomer components from the viewpoint of adhesive properties and the like.

  The acrylic polymer can be obtained by subjecting a single monomer or a mixture of two or more monomers to polymerization. The polymerization can be performed by any method such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization and the like. From the viewpoint of preventing contamination of a clean adherend, the content of the low molecular weight substance is preferably small. From this point, the number average molecular weight of the acrylic polymer is preferably 300,000 or more, more preferably about 400,000 to 3,000,000.

  Moreover, in order to increase the number average molecular weight of the acrylic polymer or the like as the base polymer, an external cross-linking agent can be appropriately employed for the pressure-sensitive adhesive. Specific examples of the external crosslinking method include a method in which a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, or a melamine crosslinking agent is added and reacted. When using an external cross-linking agent, the amount used is appropriately determined depending on the balance with the base polymer to be cross-linked, and further depending on the intended use as an adhesive. Generally, it is preferable to add about 5 parts by weight or less, and further 0.1 to 5 parts by weight with respect to 100 parts by weight of the base polymer. Furthermore, additives such as various conventionally known tackifiers and anti-aging agents may be used for the pressure-sensitive adhesive, if necessary, in addition to the above components.

  The pressure-sensitive adhesive layer 1b can be formed of a radiation curable pressure-sensitive adhesive. The radiation-curable pressure-sensitive adhesive can increase the degree of cross-linking by irradiation with radiation such as ultraviolet rays and can easily reduce its adhesive strength, and can easily peel a semiconductor wafer with an underfill material. Examples of radiation include X-rays, ultraviolet rays, electron beams, α rays, β rays, and neutron rays.

  As the radiation-curable pressure-sensitive adhesive, those having a radiation-curable functional group such as a carbon-carbon double bond and exhibiting adhesiveness can be used without particular limitation. Examples of the radiation curable pressure-sensitive adhesive include additive-type radiation curable pressure-sensitive adhesives in which radiation-curable monomer components and oligomer components are blended with general pressure-sensitive pressure-sensitive adhesives such as the above-mentioned acrylic pressure-sensitive adhesives and rubber-based pressure-sensitive adhesives. An agent can be illustrated.

  Examples of the radiation curable monomer component to be blended include urethane oligomer, urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol. Examples include stall tetra (meth) acrylate, dipentaerystol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, and the like. Examples of the radiation curable oligomer component include various oligomers such as urethane, polyether, polyester, polycarbonate, and polybutadiene, and those having a weight average molecular weight in the range of about 100 to 30000 are suitable. The compounding amount of the radiation curable monomer component or oligomer component can be appropriately determined in such an amount that the adhesive force of the pressure-sensitive adhesive layer can be reduced depending on the type of the pressure-sensitive adhesive layer. Generally, the amount is, for example, about 5 to 500 parts by weight, preferably about 40 to 150 parts by weight with respect to 100 parts by weight of the base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

  In addition to the additive-type radiation-curable adhesive described above, the radiation-curable adhesive has a carbon-carbon double bond in the polymer side chain, main chain, or main chain terminal as a base polymer. Intrinsic radiation curable adhesives using Intrinsic radiation curable adhesives do not need to contain oligomer components, which are low molecular components, or do not contain many, so they are stable without the oligomer components, etc. moving through the adhesive over time. This is preferable because an adhesive layer having a layered structure can be formed.

  As the base polymer having a carbon-carbon double bond, those having a carbon-carbon double bond and having adhesiveness can be used without particular limitation. Such a base polymer is preferably one having an acrylic polymer as a basic skeleton. Examples of the basic skeleton of the acrylic polymer include the acrylic polymers exemplified above.

  The method for introducing a carbon-carbon double bond into the acrylic polymer is not particularly limited, and various methods can be adopted. However, it is easy to design a molecule by introducing a carbon-carbon double bond into a polymer side chain. . For example, after a monomer having a functional group is copolymerized in advance with an acrylic polymer, a compound having a functional group capable of reacting with the functional group and a carbon-carbon double bond is converted into a radiation-curable carbon-carbon double bond. Examples of the method include condensation or addition reaction while maintaining the above.

  Examples of combinations of these functional groups include carboxylic acid groups and epoxy groups, carboxylic acid groups and aziridyl groups, hydroxyl groups and isocyanate groups. Among these combinations of functional groups, a combination of a hydroxyl group and an isocyanate group is preferable because of easy tracking of the reaction. In addition, the functional group may be on either side of the acrylic polymer and the compound as long as the acrylic polymer having the carbon-carbon double bond is generated by a combination of these functional groups. In the above preferred combination, it is preferable that the acrylic polymer has a hydroxyl group and the compound has an isocyanate group. In this case, examples of the isocyanate compound having a carbon-carbon double bond include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α, α-dimethylbenzyl isocyanate, and the like. As the acrylic polymer, those obtained by copolymerizing the above-exemplified hydroxy group-containing monomers, ether compounds of 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, or the like are used.

  As the internal radiation curable pressure-sensitive adhesive, the base polymer (particularly acrylic polymer) having the carbon-carbon double bond can be used alone, but the radiation curable monomer is not deteriorated. Components and oligomer components can also be blended. The radiation-curable oligomer component or the like is usually in the range of 30 parts by weight, preferably in the range of 0 to 10 parts by weight with respect to 100 parts by weight of the base polymer.

  The radiation curable pressure-sensitive adhesive preferably contains a photopolymerization initiator when cured by ultraviolet rays or the like. Examples of the photopolymerization initiator include 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α-hydroxy-α, α′-dimethylacetophenone, 2-methyl-2-hydroxypropio Α-ketol compounds such as phenone and 1-hydroxycyclohexyl phenyl ketone; methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1- [4- ( Acetophenone compounds such as methylthio) -phenyl] -2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether and anisoin methyl ether; ketal compounds such as benzyldimethyl ketal; 2-naphthalenesulfo D Aromatic sulfonyl chloride compounds such as luchloride; photoactive oxime compounds such as 1-phenyl-1,2-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; acyl phosphonate. The compounding quantity of a photoinitiator is about 0.05-20 weight part with respect to 100 weight part of base polymers, such as an acryl-type polymer which comprises an adhesive.

  In addition, when curing inhibition by oxygen occurs during irradiation, it is desirable to block oxygen (air) from the surface of the radiation curable pressure-sensitive adhesive layer 1b by some method. For example, a method of covering the surface of the pressure-sensitive adhesive layer 1b with a separator, a method of irradiating radiation such as ultraviolet rays in a nitrogen gas atmosphere, and the like can be mentioned.

  In the pressure-sensitive adhesive layer 1b, various additives (for example, a colorant, a thickener, a bulking agent, a filler, a tackifier, a plasticizer, an antiaging agent, Antioxidants, surfactants, crosslinking agents, etc.) may be included.

  The thickness of the pressure-sensitive adhesive layer 1 b is not particularly limited, but is preferably about 1 to 80 μm from the viewpoint of preventing chipping of the ground surface of the semiconductor wafer and compatibility of fixing and holding the underfill material 2. Preferably it is 2-50 micrometers, More preferably, it is 5-35 micrometers.

(Underfill material)
The underfill material 2 in the present embodiment can be used as a sealing film that fills a space between a surface-mounted semiconductor element and an adherend. The total light transmittance of the underfill material 2 may be 50% or more, preferably 60% or more, and more preferably 70% or more. Although it is preferable that the total light transmittance of the underfill material 2 is high, even when the total light transmittance is about 50%, when determining the dicing position for dicing and when matching the bonding position for mounting By using oblique light irradiation, the position of the semiconductor element can be accurately detected.

  As a constituent material of the underfill material, a combination of a thermoplastic resin and a thermosetting resin can be used. A thermoplastic resin or a thermosetting resin alone can also be used.

  Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, heat Examples thereof include plastic polyimide resins, polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluorine resins. These thermoplastic resins can be used alone or in combination of two or more. Of these thermoplastic resins, an acrylic resin that has few ionic impurities and high heat resistance and can ensure the reliability of the semiconductor element is particularly preferable.

  The acrylic resin is not particularly limited, and includes one or two or more esters of acrylic acid or methacrylic acid having a linear or branched alkyl group having 30 or less carbon atoms, particularly 4 to 18 carbon atoms. Examples include polymers as components. Examples of the alkyl group include a methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, amyl group, isoamyl group, hexyl 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, or eicosyl group.

  In addition, the other monomer forming the polymer is not particularly limited, and examples thereof include acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Carboxyl group-containing monomers such as acid anhydride monomers such as maleic anhydride or itaconic anhydride, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4- (meth) acrylic acid 4- Hydroxybutyl, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate or (4-hydroxymethylcyclohexyl) -Methyla Hydroxyl group-containing monomers such as relate, styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate or (meth) Examples include sulfonic acid group-containing monomers such as acryloyloxynaphthalenesulfonic acid, phosphoric acid group-containing monomers such as 2-hydroxyethylacryloyl phosphate, and cyano group-containing monomers such as acrylonitrile.

  Examples of the thermosetting resin include phenol resin, amino resin, unsaturated polyester resin, epoxy resin, polyurethane resin, silicone resin, and thermosetting polyimide resin. These resins can be used alone or in combination of two or more. In particular, an epoxy resin containing a small amount of ionic impurities or the like that corrode semiconductor elements is preferable. Moreover, as a hardening | curing agent of an epoxy resin, a phenol resin is preferable.

  The epoxy resin is not particularly limited as long as it is generally used as an adhesive composition, for example, bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type. Biphenyl type, naphthalene type, fluorene type, phenol novolac type, orthocresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, etc., bifunctional epoxy resin or polyfunctional epoxy resin, or hydantoin type, trisglycidyl isocyanurate Type or glycidylamine type epoxy resin is used. These can be used alone or in combination of two or more. Of these epoxy resins, novolac type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type resins or tetraphenylolethane type epoxy resins are particularly preferred. This is because these epoxy resins are rich in reactivity with a phenol resin as a curing agent and are excellent in heat resistance and the like.

  Further, the phenol resin acts as a curing agent for the epoxy resin, for example, a novolac type phenol resin such as a phenol novolac resin, a phenol aralkyl resin, a cresol novolac resin, a tert-butylphenol novolac resin, a nonylphenol novolac resin, Examples include resol-type phenolic resins and polyoxystyrenes such as polyparaoxystyrene. These can be used alone or in combination of two or more. Of these phenol resins, phenol novolac resins and phenol aralkyl resins are particularly preferred. This is because the connection reliability of the semiconductor device can be improved.

  The mixing ratio of the epoxy resin and the phenol resin is preferably such that, for example, the hydroxyl group in the phenol resin is 0.5 to 2.0 equivalents per equivalent of epoxy group in the epoxy resin component. More preferred is 0.8 to 1.2 equivalents. That is, if the blending ratio of both is out of the above range, sufficient curing reaction does not proceed and the properties of the cured epoxy resin are likely to deteriorate.

  In the present invention, an underfill material using an epoxy resin, a phenol resin and an acrylic resin is particularly preferable. Since these resins have few ionic impurities and high heat resistance, the reliability of the semiconductor element can be ensured. In this case, the mixing ratio of the epoxy resin and the phenol resin is 10 to 1000 parts by weight with respect to 100 parts by weight of the acrylic resin component.

  The thermosetting acceleration catalyst for epoxy resin and phenol resin is not particularly limited, and can be appropriately selected from known thermosetting acceleration catalysts. A thermosetting acceleration | stimulation catalyst can be used individually or in combination of 2 or more types. As the thermosetting acceleration catalyst, for example, an amine curing accelerator, a phosphorus curing accelerator, an imidazole curing accelerator, a boron curing accelerator, a phosphorus-boron curing accelerator, or the like can be used.

  A flux may be added to the underfill material 2 in order to remove the oxide film on the surface of the solder bump and facilitate mounting of the semiconductor element. The flux is not particularly limited, and a conventionally known compound having a flux action can be used.For example, diphenolic acid, adipic acid, acetylsalicylic acid, benzoic acid, benzylic acid, azelaic acid, benzylbenzoic acid, malonic acid, 2,2-bis (hydroxymethyl) propionic acid, salicylic acid, o-methoxybenzoic acid, m-hydroxybenzoic acid, succinic acid, 2,6-dimethoxymethylparacresol, benzoic hydrazide, carbohydrazide, malonic dihydrazide, succinic acid Acid dihydrazide, glutaric acid dihydrazide, salicylic acid hydrazide, iminodiacetic acid dihydrazide, itaconic acid dihydrazide, citric acid trihydrazide, thiocarbohydrazide, benzophenone hydrazone, 4,4'-oxybisbenzenesulfonylhydrazide and Adipic acid dihydrazide, and the like. The addition amount of the flux is only required to exhibit the above flux effect, and is usually about 0.1 to 20 parts by weight with respect to 100 parts by weight of the resin component contained in the underfill material.

  In the present embodiment, the underfill material 2 may be colored as long as a total light transmittance of 50% or more is obtained. In the underfill material 2, the color exhibited by coloring is not particularly limited. For example, black, blue, red, green, and the like are preferable. In coloring, it can be appropriately selected from known colorants such as pigments and dyes.

  When the underfill material 2 of the present embodiment is previously crosslinked to some extent, a polyfunctional compound that reacts with a functional group at the molecular chain end of the polymer is added as a crosslinking agent during the production. Good. Thereby, the adhesive property under high temperature can be improved and heat resistance can be improved.

  As the crosslinking agent, polyisocyanate compounds such as tolylene diisocyanate, diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, an adduct of polyhydric alcohol and diisocyanate are more preferable. The addition amount of the crosslinking agent is usually preferably 0.05 to 7 parts by weight with respect to 100 parts by weight of the polymer. When the amount of the cross-linking agent is more than 7 parts by weight, the adhesive force is lowered, which is not preferable. On the other hand, if it is less than 0.05 parts by weight, the cohesive force is insufficient, which is not preferable. Moreover, you may make it include other polyfunctional compounds, such as an epoxy resin, together with such a polyisocyanate compound as needed.

  The underfill material 2 can be appropriately mixed with an inorganic filler. The blending of the inorganic filler makes it possible to impart conductivity, improve thermal conductivity, adjust the storage elastic modulus, and the like.

  Examples of the inorganic filler include silica, clay, gypsum, calcium carbonate, barium sulfate, alumina, beryllium oxide, silicon carbide, silicon nitride, and other ceramics, aluminum, copper, silver, gold, nickel, chromium, lead. , Various inorganic powders made of metals such as tin, zinc, palladium, solder, or alloys, and other carbon. These can be used alone or in combination of two or more. Among these, silica, particularly fused silica is preferably used.

  Although the average particle diameter of the inorganic filler is not particularly limited, it is preferably in the range of 0.005 to 10 μm, more preferably in the range of 0.01 to 5 μm, and still more preferably 0.03 to 2 0.0 μm. When the average particle size of the inorganic filler is less than 0.005 μm, the particles are likely to aggregate and it may be difficult to form the underfill material. On the other hand, when the average particle diameter exceeds 10 μm, the inorganic particles tend to be caught in the joint portion between the underfill material and the adherend, so that the connection reliability of the semiconductor device may be lowered. In the present invention, inorganic fillers having different average particle sizes may be used in combination. The average particle size is a value determined by a photometric particle size distribution meter (manufactured by HORIBA, apparatus name: LA-910).

  The blending amount of the inorganic filler is preferably 10 to 400 parts by weight, more preferably 50 to 250 parts by weight with respect to 100 parts by weight of the organic resin component. If the blending amount of the inorganic filler is less than 10 parts by weight, the storage elastic modulus may be lowered and the stress reliability of the package may be greatly impaired. On the other hand, if the amount exceeds 400 parts by weight, it may cause a decrease in the total light transmittance, or the fluidity of the underfill material 2 may decrease, causing a void or crack without being sufficiently embedded in the unevenness of the substrate or semiconductor element. It may become.

  In addition to the said inorganic filler, other additives can be suitably mix | blended with the underfill material 2 as needed. Examples of other additives include flame retardants, silane coupling agents, ion trapping agents, and the like. Examples of the flame retardant include antimony trioxide, antimony pentoxide, brominated epoxy resin, and the like. These can be used alone or in combination of two or more. Examples of the silane coupling agent include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and the like. These compounds can be used alone or in combination of two or more. Examples of the ion trapping agent include hydrotalcites and bismuth hydroxide. These can be used alone or in combination of two or more.

  In the present embodiment, the melt viscosity at the thermocompression bonding temperature of the underfill material before thermosetting is preferably 20000 Pa · s or less, and more preferably 100 Pa · s or more and 10,000 Pa · s or less. By setting the melt viscosity at the thermocompression bonding temperature within the above range, the connection member 4 (see FIG. 2A) can easily enter the underfill material 2. In addition, it is possible to prevent generation of voids during electrical connection of the semiconductor element 5 and protrusion of the underfill material 2 from the space between the semiconductor element 5 and the adherend 16 (see FIG. 2H).

  Further, the viscosity at 23 ° C. of the underfill material 2 before thermosetting is preferably 0.01 MPa · s or more and 100 MPa · s or less, and more preferably 0.1 MPa · s or more and 10 MPa · s or less. . When the underfill material before thermosetting has a viscosity in the above range, the retainability of the semiconductor wafer 3 (see FIG. 2B) during back grinding and the handleability during work can be improved. In addition, the measurement of a viscosity can be performed according to the measuring method of melt viscosity.

  Further, the water absorption rate of the underfill material 2 before thermosetting under the conditions of a temperature of 23 ° C. and a humidity of 70% is preferably 1% by weight or less, and more preferably 0.5% by weight or less. When the underfill material 2 has a water absorption rate as described above, absorption of moisture into the underfill material 2 is suppressed, and generation of voids when the semiconductor element 5 is mounted can be more efficiently suppressed. The lower limit of the water absorption rate is preferably as small as possible, substantially 0% by weight is preferable, and 0% by weight is more preferable.

  Although the thickness of the underfill material 2 (total thickness in the case of multiple layers) is not particularly limited, in consideration of the strength of the underfill material 2 and the filling of the space between the semiconductor element 5 and the adherend 16, it is 10 μm or more. It may be about 100 μm or less. Note that the thickness of the underfill material 2 may be appropriately set in consideration of the gap between the semiconductor element 5 and the adherend 16 and the height of the connection member.

  The underfill material 2 of the sealing sheet 10 is preferably protected by a separator (not shown). The separator has a function as a protective material that protects the underfill material 2 until it is practically used. The separator is peeled off when the semiconductor wafer 3 is stuck on the underfill material 2 of the sealing sheet. As the separator, a plastic film or paper surface-coated with a release agent such as polyethylene terephthalate (PET), polyethylene, polypropylene, a fluorine release agent, or a long-chain alkyl acrylate release agent can be used.

(Method for producing sealing sheet)
The sealing sheet 10 according to the present embodiment can be prepared, for example, by separately preparing the back grinding tape 1 and the underfill material 2 and finally bonding them together. Specifically, it can be produced according to the following procedure.

  First, the base material 1a can be formed by a conventionally known film forming method. Examples of the film forming method include a calendar film forming method, a casting method in an organic solvent, an inflation extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, and a dry lamination method.

  Next, a pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer is prepared. Resin, additive, etc. which were demonstrated by the term of the adhesive layer are mix | blended with the adhesive composition. After the prepared pressure-sensitive adhesive composition is applied on the substrate 1a to form a coating film, the coating film is dried under predetermined conditions (heat-crosslinked as necessary) to form the pressure-sensitive adhesive layer 1b. . It does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 80 to 150 ° C. and the drying time is 0.5 to 5 minutes. Moreover, after apply | coating an adhesive composition on a separator and forming a coating film, the coating film may be dried on the said dry conditions, and the adhesive layer 1b may be formed. Then, the adhesive layer 1b is bonded together with a separator on the base material 1a. Thereby, the tape 1 for back surface grinding provided with the base material 1a and the adhesive layer 1b is produced.

  The underfill material 2 is produced as follows, for example. First, an adhesive composition that is a material for forming the underfill material 2 is prepared. As described in the section of the underfill material, the adhesive composition contains a thermoplastic component, an epoxy resin, various additives, and the like.

  Next, after applying the prepared adhesive composition on the base separator so as to have a predetermined thickness to form a coating film, the coating film is dried under predetermined conditions to form an underfill material. It does not specifically limit as a coating method, For example, roll coating, screen coating, gravure coating, etc. are mentioned. As drying conditions, for example, the drying temperature is 70 to 160 ° C. and the drying time is 1 to 5 minutes. Moreover, after apply | coating an adhesive composition on a separator and forming a coating film, an underfill material may be formed by drying a coating film on the said drying conditions. Then, an underfill material is bonded together with a separator on a base material separator.

  Subsequently, the separator is peeled off from the back surface grinding tape 1 and the underfill material 2, and both are bonded so that the underfill material and the pressure-sensitive adhesive layer become a bonding surface. Bonding can be performed by, for example, pressure bonding. At this time, the lamination temperature is not particularly limited, and for example, 30 to 100 ° C is preferable, and 40 to 80 ° C is more preferable. Further, the linear pressure is not particularly limited, and for example, 0.98 to 196 N / cm is preferable, and 9.8 to 98 N / cm is more preferable. Next, the base material separator on the underfill material is peeled off, and the sealing sheet according to the present embodiment is obtained.

[Lamination process]
In the bonding step, the circuit surface 3a on which the connection member 4 of the semiconductor wafer 3 is formed and the underfill material 2 of the sealing sheet 10 are bonded together (see FIG. 2A).

(Semiconductor wafer)
A plurality of connection members 4 are formed on the circuit surface 3a of the semiconductor wafer 3 (see FIG. 2A). The material of the connection member such as a bump or a conductive material is not particularly limited. For example, a tin-lead metal material, a tin-silver metal material, a tin-silver-copper metal material, a tin-zinc metal material, Examples thereof include solders (alloys) such as a tin-zinc-bismuth metal material, a gold metal material, and a copper metal material. The height of the connecting member is also determined according to the application, and is generally about 15 to 100 μm. Of course, the height of each connection member in the semiconductor wafer 3 may be the same or different.

In the method for manufacturing a semiconductor device according to the present embodiment, the thickness of the underfill material includes a height X (μm) of the connecting member formed on the surface of the semiconductor wafer and a thickness Y (μm) of the underfill material. However, it is preferable to satisfy | fill the following relationship.
0.5 ≦ Y / X ≦ 2

  When the height X (μm) of the connecting member and the thickness Y (μm) of the cured film satisfy the above relationship, the space between the semiconductor element and the adherend can be sufficiently filled. Further, excessive protrusion of the underfill material from the space can be prevented, and contamination of the semiconductor element by the underfill material can be prevented. In addition, when the height of each connection member differs, the height of the highest connection member is used as a reference.

(Lamination)
First, the separator arbitrarily provided on the underfill material 2 of the sealing sheet 10 is appropriately peeled off, and as shown in FIG. 2A, the circuit surface 3a on which the connection member 4 of the semiconductor wafer 3 is formed and the underfill The material 2 is made to face, and the underfill material 2 and the semiconductor wafer 3 are bonded together (mounting).

  The method of bonding is not particularly limited, but a method by pressure bonding is preferable. The crimping is usually performed by a known pressing means such as a crimping roll while applying a pressure of 0.1 to 1 MPa, more preferably 0.3 to 0.7 MPa. Under the present circumstances, you may make it press-fit, heating at about 40-100 degreeC. Moreover, in order to improve adhesiveness, it is also preferable to press-fit under reduced pressure (1-1000 Pa).

[Grinding process]
In the grinding step, the surface (that is, the back surface) 3b opposite to the circuit surface 3a of the semiconductor wafer 3 is ground (see FIG. 2B). The thin processing machine used for back surface grinding of the semiconductor wafer 3 is not particularly limited, and examples thereof include a grinding machine (back grinder) and a polishing pad. Further, the back surface grinding may be performed by a chemical method such as etching. The back surface grinding is performed until the semiconductor wafer has a desired thickness (for example, 700 to 25 μm).

[Fixing process]
After the grinding step, the semiconductor wafer 3 is peeled from the back surface grinding tape 1 with the underfill material 2 attached, and the semiconductor wafer 3 and the dicing tape 11 are attached (see FIG. 2C). At this time, bonding is performed so that the back surface 3b of the semiconductor wafer 3 and the adhesive layer 11b of the dicing tape 11 face each other. Therefore, the underfill material 2 bonded to the circuit surface 3a of the semiconductor wafer 3 is exposed. The dicing tape 11 has a structure in which an adhesive layer 11b is laminated on a substrate 11a. The base material 11a and the pressure-sensitive adhesive layer 11b can be suitably produced by using the components and the production methods shown in the paragraphs of the base material 1a and the pressure-sensitive adhesive layer 1b of the back grinding tape 1.

  When the pressure-sensitive adhesive layer 1b has radiation curability when the semiconductor wafer 3 is peeled from the back surface grinding tape 1, the pressure-sensitive adhesive layer 1b is irradiated with radiation to cure the pressure-sensitive adhesive layer 1b. Can be easily performed. The radiation dose may be appropriately set in consideration of the type of radiation used, the degree of cure of the pressure-sensitive adhesive layer, and the like.

[Dicing position determination process]
Next, in the dicing position determination step, as shown in FIGS. 2D and 3A, the exposed surface 2 a of the underfill material 2 of the semiconductor wafer 3 with the underfill material is irradiated with oblique light L, and the semiconductor wafer 3 Determine the dicing position. Thereby, the dicing position of the semiconductor wafer 3 can be detected with high accuracy, and the dicing of the semiconductor wafer 3 can be performed simply and efficiently.

  Specifically, an imaging device 31a and ring illumination (illumination having a circular light emitting surface) 32a are arranged above the semiconductor wafer 3 fixed to the dicing tape 11. Next, oblique light L is irradiated from the ring illumination 32a to the exposed surface 2a of the underfill material 2 at a predetermined incident angle α. The light entering the underfill material 2 and reflected by the semiconductor wafer 3 is received as a reflected image by the imaging device 31a. The received reflected image is analyzed by an image recognition device, and a position to be diced is determined. Thereafter, this process is completed (not shown) by moving a dicing apparatus (for example, a dicing blade, a laser oscillator, etc.) and aligning it with the dicing position.

  As illumination for oblique light irradiation, ring illumination can be suitably used as described above. However, the illumination is not limited to this, and line illumination (light emission surface having a linear shape) or spot illumination (light emission surface) Can be used. Moreover, the illumination which combined the some line illumination in the polygonal shape, and the illumination which combined the spot illumination in the polygonal shape or the ring shape may be sufficient.

  The light source for illumination is not particularly limited, and examples thereof include halogen lamps, LEDs, fluorescent lamps, tungsten lamps, metal halide lamps, xenon lamps, and black lights. Further, the oblique light L emitted from the light source may be either a parallel light beam or a radiation beam (non-parallel light beam), but a parallel light beam is preferable in consideration of irradiation efficiency and ease of setting the incident angle α. . However, since there is a physical limit to irradiating the oblique light L as a parallel light beam, it may be a substantially parallel light beam (half-value angle within 30 °). The oblique light L may be polarized light.

  In this embodiment, it is preferable to irradiate the oblique light from two or more directions or all directions with respect to the exposed surface of the underfill material. By oblique light irradiation from multiple directions or all directions (circumferential directions), the diffuse reflection from the semiconductor wafer can be increased to improve the position detection accuracy, and the dicing position detection accuracy can be further improved. Irradiation from multiple directions can be performed by combining one or both of the line illumination and spot illumination. Irradiation in all directions or all directions can be easily performed by combining the plurality of line illuminations into a polygonal shape or using ring illumination.

  Although the incident angle α is not particularly limited as long as the oblique light L is irradiated with an inclination with respect to the exposed surface 2a of the underfill material 2, it is preferably 5 to 85 °, more preferably 15 to 75 °, and more preferably 30 to 60. ° is particularly preferred. By setting the incident angle α within the above range, it is possible to prevent regular reflection light from the semiconductor wafer 3 that causes halation, and to increase the detection accuracy of the dicing position of the semiconductor wafer. When the oblique light L is a radiated light (non-parallel light), a certain width may be generated in the incident angle α depending on the relationship between the starting point of the oblique light L irradiation and the arrival point on the exposed surface 2a of the underfill material 2. There is. In that case, the angle at which the light amount of the oblique light L is maximized may be within the range of the incident angle α.

  The wavelength of the oblique light is not particularly limited as long as a reflected image from the semiconductor wafer 3 is obtained and the semiconductor wafer 3 is not damaged, but is preferably 300 to 900 nm, and more preferably 400 to 800 nm. When the wavelength of the oblique light is set in the above range, good transmittance is exhibited even for an underfill material formed of a general material including an inorganic filler, so that the dicing position can be detected more easily.

  Further, the recognition target in the semiconductor wafer for position detection by oblique light irradiation is the connection member (for example, bump) 4 formed on the semiconductor wafer 3 in FIGS. 2D and 3A, but is not limited thereto. Arbitrary marks or structures such as alignment marks, terminals, and circuit patterns can be recognized.

[Dicing process]
In the dicing process, based on the dicing position determined in the dicing position determination process, the semiconductor element 5 with the underfill material is formed by dicing the semiconductor wafer 3 and the underfill material 2 as shown in FIG. 2E. By passing through a dicing process, the semiconductor wafer 3 is cut into a predetermined size and divided into pieces (small pieces), and a semiconductor chip (semiconductor element) 5 is manufactured. The semiconductor chip 5 obtained here is integrated with the underfill material 2 cut into the same shape. Dicing is performed according to a conventional method from the circuit surface 3a on which the underfill material 2 of the semiconductor wafer 3 is bonded.

  In this step, for example, a cutting method called full cut for cutting up to the dicing tape 11 can be adopted. It does not specifically limit as a dicing apparatus used at this process, A conventionally well-known thing can be used. Further, since the semiconductor wafer is bonded and fixed with excellent adhesion by the dicing tape 11, chip chipping and chip jumping can be suppressed, and damage to the semiconductor wafer can also be suppressed. In addition, when the underfill material is formed of a resin composition containing an epoxy resin, even if the underfill material is cut by dicing, the underfill material of the underfill material is prevented or prevented from protruding on the cut surface. Can do. As a result, it is possible to suppress or prevent the cut surfaces from reattaching (blocking), and the pickup described later can be performed more satisfactorily.

  In addition, when expanding a dicing tape following a dicing process, this expansion can be performed using a conventionally well-known expanding apparatus. The expanding apparatus includes a donut-shaped outer ring that can push down the dicing tape through the dicing ring, and an inner ring that has a smaller diameter than the outer ring and supports the dicing tape. By this expanding process, it is possible to prevent adjacent semiconductor chips from coming into contact with each other and being damaged in a pickup process described later.

[Pickup process]
In order to collect the semiconductor chip 5 bonded and fixed to the dicing tape 11, as shown in FIG. 2F, the semiconductor chip 5 with the underfill material 2 is picked up, and the laminated body of the semiconductor chip 5 and the underfill material 2 is collected. A is peeled off from the dicing tape 11.

  The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, a method of pushing up individual semiconductor chips from the base material side of the dicing tape with a needle and picking up the pushed-up semiconductor chips with a pickup device can be mentioned. The picked-up semiconductor chip 5 constitutes a laminate A integrally with the underfill material 2 bonded to the circuit surface 3a.

  Here, when the pressure-sensitive adhesive layer 11b is an ultraviolet curable type, the pickup is performed after the pressure-sensitive adhesive layer 11b is irradiated with ultraviolet light. Thereby, the adhesive force with respect to the semiconductor chip 5 of the adhesive layer 11b falls, and peeling of the semiconductor chip 5 becomes easy. As a result, the pickup can be performed without damaging the semiconductor chip 5. Conditions such as irradiation intensity and irradiation time at the time of ultraviolet irradiation are not particularly limited, and may be set as necessary. Moreover, as a light source used for ultraviolet irradiation, for example, a low-pressure mercury lamp, a low-pressure high-power lamp, a medium-pressure mercury lamp, an electrodeless mercury lamp, a xenon flash lamp, an excimer lamp, an ultraviolet LED, or the like can be used.

[Position alignment process]
Next, in the alignment process, as shown in FIGS. 2G and 3B, oblique light L is applied to the exposed surface 2a of the underfill material 2 of the semiconductor element 5 with the underfill material, The relative position with the adherend 16 is aligned with the planned connection position. Thereby, the position of the semiconductor element 5 can be detected with high accuracy, and the semiconductor element 5 and the adherend 16 can be easily and efficiently aligned with the planned connection position.

  Specifically, the picked-up laminate A is attached to the adherend 16 so that the surface of the semiconductor element 5 on which the connection member 4 is formed (corresponding to the circuit surface 3 a of the semiconductor wafer 3) faces the adherend 16. Place above. Next, after the imaging device 31b and the ring illumination 32b are arranged between the stacked body A and the adherend 16, the predetermined incidence is made on the exposed surface 2a of the underfill material 2 from the ring illumination 32b toward the stacked body A. The oblique light L is irradiated at an angle α. The light that enters the underfill material 2 and is reflected by the semiconductor element 5 is received as a reflected image by the imaging device 31b. Next, the received reflection image is analyzed by an image recognition device to obtain a deviation from a predetermined connection scheduled position. Finally, the stacked body A is moved by the obtained deviation amount to adhere to the semiconductor element 5. The relative position with the body 16 is aligned with the planned connection position (not shown).

  The aspect of the oblique light irradiation in this position alignment process is that the positions of the exposed surface 2a of the underfill material, the imaging device 31b, and the illumination 32b are vertically inverted from the oblique light irradiation in the dicing position determination process. Therefore, various conditions for oblique light irradiation, such as illumination for oblique light irradiation, illumination light source, irradiation direction, range of incident angle α, wavelength of oblique light, recognition target in a semiconductor element for position detection by oblique light irradiation, etc. As, the conditions described in the section of the dicing position determination step can be preferably adopted, and the same effect can be obtained.

[Mounting process]
In the mounting process, the semiconductor element 5 and the adherend 16 are electrically connected through the connection member 4 while filling the space between the adherend 16 and the semiconductor element 5 with the underfill material 2 (see FIG. 2H). ). Specifically, the semiconductor chip 5 of the stacked body A is fixed to the adherend 16 according to a conventional method with the circuit surface 3a of the semiconductor chip 5 facing the adherend 16. For example, bumps (connection members) 4 formed on the semiconductor chip 5 are brought into contact with a bonding conductive material 17 (solder or the like) attached to the connection pads of the adherend 16 while pressing the conductive material. By melting, the electrical connection between the semiconductor chip 5 and the adherend 16 can be secured, and the semiconductor chip 5 can be fixed to the adherend 16. Since the underfill material 2 is affixed to the circuit surface 3 a of the semiconductor chip 5, the space between the semiconductor chip 5 and the adherend 16 as well as the electrical connection between the semiconductor chip 5 and the adherend 16. Is filled with the underfill material 2.

  Generally, the heating condition in the mounting process is 100 to 300 ° C., and the pressurizing condition is 0.5 to 500 N. Moreover, you may perform the thermocompression-bonding process in a mounting process in multistep. For example, it is possible to adopt a procedure in which treatment is performed at 150 ° C. and 100 N for 10 seconds and then treatment is performed at 300 ° C. and 100 to 200 N for 10 seconds. By performing thermocompression bonding in multiple stages, the resin between the connection member and the pad can be efficiently removed, and a better metal-to-metal bond can be obtained.

  As the adherend 16, various substrates such as a lead frame and a circuit board (such as a wiring circuit board), and other semiconductor elements can be used. The material of the substrate is not particularly limited, and examples thereof include a ceramic substrate and a plastic substrate. Examples of the plastic substrate include an epoxy substrate, a bismaleimide triazine substrate, a polyimide substrate, and a glass epoxy substrate.

  In the mounting process, one or both of the connection member and the conductive material are melted to connect the bumps 4 on the connection member forming surface 3a of the semiconductor chip 5 and the conductive material 17 on the surface of the adherend 16. However, the temperature at the time of melting the bump 4 and the conductive material 17 is usually about 260 ° C. (for example, 250 ° C. to 300 ° C.). The sealing sheet according to the present embodiment can have heat resistance that can withstand high temperatures in the mounting process by forming the underfill material 2 with an epoxy resin or the like.

[Underfill material curing process]
After the electrical connection between the semiconductor element 5 and the adherend 16 is performed, the underfill material 2 is cured by heating. Thereby, the surface of the semiconductor element 5 can be protected, and the connection reliability between the semiconductor element 5 and the adherend 16 can be ensured. It does not specifically limit as heating temperature for hardening of an underfill material, What is necessary is just about 150-250 degreeC. In addition, when an underfill material hardens | cures by the heat processing in a mounting process, this process can be abbreviate | omitted.

[Sealing process]
Next, a sealing step may be performed in order to protect the entire semiconductor device 20 including the mounted semiconductor chip 5. The sealing step is performed using a sealing resin. Although it does not specifically limit as sealing conditions at this time, Usually, the thermosetting of the sealing resin is performed by heating at 175 ° C. for 60 seconds to 90 seconds, but the present invention is not limited thereto, For example, it can be cured at 165 ° C. to 185 ° C. for several minutes.

  The sealing resin is not particularly limited as long as it is an insulating resin (insulating resin), and can be appropriately selected from sealing materials such as known sealing resins. Is more preferable. As sealing resin, the resin composition containing an epoxy resin etc. are mentioned, for example. Examples of the epoxy resin include the epoxy resins exemplified above. Moreover, as a sealing resin by the resin composition containing an epoxy resin, in addition to an epoxy resin, a thermosetting resin other than an epoxy resin (such as a phenol resin) or a thermoplastic resin may be included as a resin component. Good. In addition, as a phenol resin, it can utilize also as a hardening | curing agent of an epoxy resin, As such a phenol resin, the phenol resin illustrated above etc. are mentioned.

[Semiconductor device]
Next, a semiconductor device obtained using the sealing sheet will be described with reference to the drawing (see FIG. 2H). In the semiconductor device 20 according to the present embodiment, the semiconductor element 5 and the adherend 16 are connected via the bump (connection member) 4 formed on the semiconductor element 5 and the conductive material 17 provided on the adherend 16. Are electrically connected. An underfill material 2 is disposed between the semiconductor element 5 and the adherend 16 so as to fill the space. Since the semiconductor device 20 is obtained by the above manufacturing method that employs a predetermined underfill material 2 and alignment by oblique light irradiation, good electrical connection is achieved between the semiconductor element 5 and the adherend 16. Yes. Accordingly, the surface protection of the semiconductor element 5, the filling of the space between the semiconductor element 5 and the adherend 16, and the electrical connection between the semiconductor element 5 and the adherend 16 become sufficient levels, respectively, and the semiconductor device High reliability can be demonstrated as 20.

Second Embodiment
In the first embodiment, a semiconductor wafer having a circuit formed on one side is used, whereas in the present embodiment, a semiconductor device is manufactured using a semiconductor wafer having a circuit formed on both sides. Further, since the semiconductor wafer used in this embodiment has a target thickness, the grinding step is omitted. Accordingly, as the sealing sheet in the second embodiment, a sealing sheet including a dicing tape and an underfill material having a total light transmittance of 50% or more laminated on the dicing tape is used. As a representative process prior to the position alignment process in the second embodiment, a preparation process for preparing the sealing sheet, a semiconductor wafer having circuit surfaces having connection members formed on both sides, and an underfill of the sealing sheet A bonding step of bonding a material, a dicing step of dicing the semiconductor wafer to form a semiconductor element with the underfill material, and a pickup step of peeling the semiconductor element with the underfill material from the sealing sheet. It is done. Thereafter, the semiconductor device is manufactured by performing the steps after the position alignment step.

[Preparation process]
In the preparation step, a sealing sheet including a dicing tape 41 and an underfill material 42 having a total light transmittance of 50% or more laminated on the dicing tape 41 is prepared (see FIG. 4A). The dicing tape 41 includes a base material 41a and an adhesive layer 41b laminated on the base material 41a. The underfill material 42 is laminated on the pressure-sensitive adhesive layer 41b. As the base material 41a and the pressure-sensitive adhesive layer 41b of the dicing tape 41 and the underfill material 42, the same materials as those in the first embodiment can be used.

[Lamination process]
In the laminating step, as shown in FIG. 4A, the semiconductor wafer 43 on which the circuit surface having the connection member 44 is formed on both sides is bonded to the underfill material 42 of the sealing sheet. In addition, since the strength of the semiconductor wafer thinned to a predetermined thickness is weak, the semiconductor wafer may be fixed to a support such as support glass via a temporary fixing material (not shown) for reinforcement. . In this case, the process of peeling a support body with a temporary fixing material after bonding a semiconductor wafer and an underfill material may be included. Which circuit surface of the semiconductor wafer 43 and the underfill material 42 are bonded together may be changed according to the structure of the target semiconductor device.

  The semiconductor wafer 43 is the same as the semiconductor wafer of the first embodiment except that the circuit surface having the connection member 44 is formed on both surfaces and has a predetermined thickness. The connection members 44 on both surfaces of the semiconductor wafer 43 may be electrically connected or may not be connected. Examples of the electrical connection between the connection members 44 include a connection through a via called a TSV format. As the bonding conditions, the bonding conditions in the first embodiment can be suitably employed.

[Dicing process]
In the dicing process, the semiconductor wafer 43 and the underfill material 42 are diced to form the semiconductor element 45 with the underfill material (see FIG. 4B). As the dicing conditions, the conditions in the first embodiment can be suitably employed. Although dicing is performed on the exposed circuit surface of the semiconductor wafer 43, it is easy to detect the dicing position. However, dicing may be performed after confirming the dicing position by irradiating oblique light as necessary. Good.

[Pickup process]
In the pickup process, the semiconductor element 45 with the underfill material 42 is peeled from the dicing tape 41 (FIG. 4C). As the pickup conditions, various conditions in the first embodiment can be suitably employed.

[Position alignment process]
Next, in the position alignment process, as shown in FIG. 4D, the exposed surface 42a of the underfill material 42 of the semiconductor element 45 with the underfill material is irradiated with oblique light L so that the semiconductor element 45 and the deposition are deposited. The relative position with respect to the body 66 is aligned with the planned connection position. Thereby, the position of the semiconductor element 45 can be detected with high accuracy, and the semiconductor element 45 and the adherend 66 can be easily and efficiently aligned with the planned connection position. The conditions in the first embodiment can be suitably used as the conditions in the position alignment process.

[Mounting process]
In the mounting process, the semiconductor element 45 and the adherend 66 are electrically connected via the connection member 44 while the space between the adherend 66 and the semiconductor element 45 is filled with the underfill material 42 (see FIG. 4E). ). Various conditions in the first embodiment can be suitably employed as the conditions in the mounting process. Thereby, the semiconductor device 60 according to the present embodiment can be manufactured.

  Thereafter, as in the first embodiment, an underfill material curing step and a sealing step may be performed as necessary.

<Third Embodiment>
In the first embodiment, the back surface grinding tape is used as a constituent member of the sealing sheet. However, in this embodiment, the base material alone is used without providing the adhesive layer of the back surface grinding tape. Therefore, as a sealing sheet of this embodiment, it will be in the state where the underfill material was laminated on the substrate. In this embodiment, although the grinding process can be performed arbitrarily, ultraviolet irradiation before the pick-up process is not performed by omitting the adhesive layer. Except for these points, a predetermined semiconductor device can be manufactured through the same steps as in the first embodiment.

<Fourth embodiment>
In the present embodiment, an underfill material having a different form from the first embodiment will be described. In the underfill material of the first embodiment, the total light transmittance is 50% or more, whereas in the underfill material of this embodiment, the surface-treated average particle diameter is 0.1 μm or less instead of the configuration. An inorganic filler, a thermosetting resin, a thermoplastic resin, and a curing accelerating catalyst are essential components. By adopting such a component, it is possible to ensure the total light transmittance necessary for accurate alignment between the semiconductor element and the adherend. Further, with the underfill material of this embodiment, it is possible to ensure good alignment mark visibility without using the oblique light described in the first embodiment. Hereinafter, differences from the first embodiment will be mainly described. For other configurations and manufacturing methods, the description in the first embodiment can be preferably referred to.

  Although the average particle diameter of the inorganic filler of this embodiment is not particularly limited as long as it is 0.1 μm or less, it is preferably within the range of 0.001 to 0.1 μm, and within the range of 0.005 to 0.1 μm. More preferably, it is 0.01-0.1 micrometer. When the average particle diameter of the inorganic filler is less than the lower limit, aggregation of particles tends to occur, and it may be difficult to form an underfill material. On the other hand, if the average particle size exceeds the upper limit, inorganic particles are likely to be caught in the joint between the underfill material and the adherend, and the connection reliability of the semiconductor device may be reduced. . In addition, the influence of the presence of the inorganic filler cannot be ignored, and the transparency of the underfill material may be reduced. In the present invention, inorganic fillers having different average particle sizes may be used in combination. The average particle size is a value determined by a photometric particle size distribution meter (manufactured by HORIBA, apparatus name: LA-910).

  In this embodiment, an inorganic filler subjected to surface treatment is used as the inorganic filler. The surface treatment is not particularly limited as long as the treatment improves the affinity with the organic component contained in the underfill material, particularly the resin component. Examples of the surface treatment agent for the surface treatment include silane coupling agents, titanate coupling agents, carboxylic acid coupling agents, coupling agents such as phosphoric acid coupling agents, fatty acids such as stearic acid and oleic acid, Examples thereof include surfactants such as resin acids, polyethylene glycol and derivatives thereof, polyolefin waxes and oxides or acid-modified products thereof. Of these, treatment with a silane coupling agent is preferable from the viewpoint of ease of treatment and improvement of dispersibility after treatment. By using an inorganic filler that has been subjected to such surface treatment, the affinity with the organic component, particularly the resin component, contained in the underfill material is increased, and the dispersibility of the inorganic filler is also improved. The transparency of the fill material can be improved.

  The upper limit of the content of the inorganic filler is preferably 70% by weight or less, more preferably 65% by weight or less, and further preferably 60% by weight or less. Further, the lower limit of the content of the inorganic filler is preferably 20% by weight or more, more preferably 30% by weight or more, and further preferably 40% by weight or more. By setting the content of the inorganic filler in the above range, the low thermal linear expansion coefficient and good transparency of the underfill material can be maintained, and the alignment between the semiconductor element and the adherend can be accurately performed. it can.

  Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, the materials, blending amounts, and the like described in the examples are not intended to limit the scope of the present invention only to those unless otherwise specified. The term “parts” means parts by weight.

(Preparation of sealing sheet)
The following components were dissolved in methyl ethyl ketone in the proportions shown in Table 1 to prepare an adhesive composition solution having a solid content concentration of 23.6 to 60.6% by weight.

Elastomer 1: Acrylic acid ester polymer mainly composed of ethyl acrylate-methyl methacrylate (trade name “Paracron W-197CM”, manufactured by Negami Industrial Co., Ltd.)
Elastomer 2: Acrylic ester polymer based on butyl acrylate-acrylonitrile (trade name “SG-P3”, manufactured by Nagase Chemtex Co., Ltd.)
Epoxy resin 1: Trade name “Epicoat 828”, manufactured by JER Corporation Epoxy resin 2: Trade name “Epicoat 1004”, manufactured by JER Corporation Phenolic resin: Trade name “Millex XLC-4L”, Mitsui Chemicals, Inc. Filler 1: Spherical Silica (trade name “SO-25R”, manufactured by Admatechs Co., Ltd., average particle size 0.5 μm (500 nm), surface treatment: none)
Filler 2: Spherical silica (trade name “YC100C-MLC”, manufactured by Admatechs Co., Ltd., average particle size 0.1 μm (100 nm), surface treatment: silane coupling agent)
Filler 3: Spherical silica (trade name “YA050C-MJC”, manufactured by Admatechs Co., Ltd., average particle size 0.05 μm (50 nm), surface treatment: silane coupling agent)
Filler 4: Spherical silica (trade name “SC1050-MB”, manufactured by Admatechs Co., Ltd., average particle size 0.3 μm (300 nm), surface treatment: silane coupling agent)
Filler 5: Spherical silica (trade name “YA050C”, manufactured by Admatechs Co., Ltd., average particle size 0.05 μm (50 nm), surface treatment: none)
Organic acid: o-anisic acid (trade name “Orthoanisic acid”, manufactured by Tokyo Chemical Industry Co., Ltd.)
Curing agent: Imidazole catalyst (trade name “2PHZ-PW”, manufactured by Shikoku Kasei Co., Ltd.)

  The prepared adhesive composition solution was applied as a release liner (separator) on a release film made of a polyethylene terephthalate film having a thickness of 50 μm and then dried at 130 ° C. for 2 minutes. Underfill materials A to F having a thickness of 45 μm were prepared.

  The underfill material was bonded onto the adhesive layer of a back grind tape (trade name “UB-2154”, manufactured by Nitto Denko Corporation) using a hand roller to prepare sealing sheets A to F.

(Measurement of total light transmittance of underfill material)
The total light transmittance of the underfill materials A to F was measured using a haze meter HM-150 (manufactured by Murakami Color Research Laboratory). The measurement was performed according to JIS K 7361. The results are shown in Table 1.

[Example 1]
(Fabrication of semiconductor devices)
Prepare a silicon wafer with single-sided bumps with bumps formed on one side, and bond the prepared sealing sheet to the surface on which the bumps of the silicon wafer with single-sided bumps are formed, with an underfill material as the bonding surface Thermocompression bonding was performed. As a silicon wafer with a single-sided bump, the following was used. The thermocompression bonding conditions are as follows. The ratio (Y / X) of the thickness Y (= 45 μm) of the underfill material to the height X (= 45 μm) of the connecting member was 1. At the four corners of the region (7.3 mm square) cut out as a semiconductor element, alignment marks were made at locations 0.15 mm from each side.

<Silicon wafer with single-sided bump>
Product name “WALTS-TEG MB50-0101JY_TYPE-B (PI)”, manufactured by Waltz Co., Ltd. Silicon wafer diameter: 8 inches Silicon wafer thickness: 0.7 mm (700 μm)
Bump height: 45μm
Bump pitch: 50 μm
Bump material: SnAg solder + copper pillar

<Thermocompression conditions>
Pasting device: Product name “DSA840-WS”, manufactured by Nitto Seiki Co., Ltd. Pasting speed: 5 mm / min
Pasting pressure (pressing): 0.5 MPa
Stage temperature at the time of pasting (thermocompression bonding temperature): 80 ° C
Decompression degree when pasting: 150 Pa

  After bonding the silicon wafer with a single-sided bump and the sealing sheet A according to the above procedure, the back surface of the silicon wafer was ground under the following conditions.

<Grinding conditions>
Grinding equipment: Trade name “DFG-8560”, manufactured by DISCO Semiconductor wafer: Back grinding from 0.7 mm (700 μm) to 0.2 mm (200 μm)

  After the back surface grinding, the silicon wafer was peeled off from the back grind tape together with the underfill material, and the silicon wafer was bonded and fixed on the adhesive layer of a dicing tape (DU-300, manufactured by Nitto Denko Corporation). At this time, the back surface of the silicon wafer and the adhesive layer were bonded together, and the underfill material bonded to the circuit surface of the silicon wafer was exposed.

  Dicing position was determined by irradiating the exposed surface of the underfill material with oblique light at an incident angle of 45 °.

  Next, dicing of the silicon wafer was performed under the following conditions. Dicing was fully cut so as to obtain a chip size of 7.3 mm square.

<Dicing conditions>
Dicing machine: Trade name “DFD-6361” manufactured by Disco Corporation Dicing ring: “2-8-1” (manufactured by Disco Corporation)
Dicing speed: 30mm / sec
Dicing blade:
Z1; "203O-SE 27HCDD" manufactured by DISCO
Z2: “203O-SE 27HCBB” manufactured by Disco Corporation
Dicing blade rotation speed:
Z1; 40,000 rpm
Z2; 45,000 rpm
Cut method: Step cut Wafer chip size: 7.3mm square

  Next, the laminated body of the underfill material A and the semiconductor chip with single-sided bumps was picked up by a needle push-up method from the base material side of the dicing tape. The pickup conditions are as follows.

<Pickup conditions>
Pickup device: Brand name “SPA-300” manufactured by Shinkawa Co., Ltd. Number of needles: 9 Needle push-up amount: 500 μm (0.5 mm)
Needle push-up speed: 20 mm / second Pickup time: 1 second Expanding amount: 3 mm

  The exposed surface of the underfill material A is aligned at an incident angle α of 45 ° by oblique light irradiation. Finally, the bump formation surface of the semiconductor chip and the BGA substrate are opposed to each other at the planned connection position according to the following mounting conditions. In this state, the semiconductor chip was mounted on the BGA substrate. Thus, a semiconductor device in which the semiconductor chip was mounted on the BGA substrate was obtained. In this step, a two-stage process for performing the mounting condition 2 following the mounting condition 1 was performed.

<Mounting condition 1>
Pickup device: Product name “FCB-3” manufactured by Panasonic Heating temperature: 150 ° C.
Load: 98N
Holding time: 10 seconds

<Mounting condition 2>
Pickup device: Product name “FCB-3” manufactured by Panasonic Heating temperature: 260 ° C.
Load: 98N
Holding time: 10 seconds

[Example 2]
A semiconductor device was fabricated in the same manner as in Example 1 except that the incident angle of oblique light at the time of alignment was 15 °.

[Example 3]
A semiconductor device was fabricated in the same manner as in Example 1 except that the incident angle of oblique light at the time of alignment was 80 °.

[Example 4]
A semiconductor device was produced in the same manner as in Example 1 except that the sealing sheet B including the underfill material B was used instead of the sealing sheet A.

[Example 5]
A semiconductor device was fabricated in the same manner as in Example 1 except that the back grind tape was not bonded to the underfill material A and a laminate of the release film and the underfill material A was used as the sealing sheet.

[Example 6]
A semiconductor device was fabricated in the same manner as in Example 1 except that the sealing sheet D provided with the underfill material D was used instead of the sealing sheet A and that the oblique light was not irradiated.

[Example 7]
A semiconductor device was produced in the same manner as in Example 1 except that the sealing sheet E including the underfill material E was used instead of the sealing sheet A, and the oblique light was not irradiated.

[Comparative Example 1]
A semiconductor device was fabricated in the same manner as in Example 1 except that the oblique light was not irradiated.

[Comparative Example 2]
A semiconductor device was fabricated in the same manner as in Example 1 except that the sealing sheet C including the underfill material C was used instead of the sealing sheet A.

[Comparative Example 3]
A semiconductor device was fabricated in the same manner as in Example 1 except that the sealing sheet F including the underfill material F was used instead of the sealing sheet A, and the oblique light was not irradiated.

[Comparative Example 4]
A semiconductor device was fabricated in the same manner as in Example 1 except that the sealing sheet G including the underfill material G was used in place of the sealing sheet A, and the oblique light was not irradiated.

(Evaluation of solder joints)
Ten samples of each of the semiconductor devices according to Examples and Comparative Examples were prepared, and the semiconductor devices were embedded with an embedding epoxy resin. Next, the semiconductor device was cut in a direction perpendicular to the substrate so that the solder joint portion was exposed, and the cross section of the exposed solder joint portion was polished. Then, the cross section of the polished solder joint is observed with an optical microscope (magnification: 1000 times). When the solder joint is joined, “◯”, even in one sample, the solder joint is displaced, and the board side pad The case where it was not joined was evaluated as “×”.

  As can be seen from Table 1, in the semiconductor device according to the example, the solder joint did not shift. On the other hand, in the semiconductor device of the comparative example, the solder joint was misaligned. In Comparative Example 1, the oblique light was not irradiated, and in Comparative Examples 2 and 3, the total light transmittance of the underfill material was too low, so that the alignment mark provided on the semiconductor element could not be accurately recognized. It is considered that a positional shift occurred when the semiconductor element was bonded to the adherend. Furthermore, in Examples 6 and 7, since an inorganic filler having an average particle size of 0.1 μm or less subjected to surface treatment was used, good bonding was obtained without irradiation with oblique light. From the results of Example 7 and Comparative Example 4, it is considered that a noticeable difference in total light transmittance occurred depending on the presence or absence of the surface treatment of the inorganic filler, thereby affecting the evaluation of the solderability.

DESCRIPTION OF SYMBOLS 1 Back surface grinding tape 1a, 11a Base material 1b, 11b Adhesive layer 2, 42 Underfill material 2a, 42a Underfill material exposed surface 3, 43 Semiconductor wafer 3a, 43a Semiconductor wafer circuit surface 3b Semiconductor wafer circuit surface Surface on the opposite side 4, 44 Bump (connection member)
5, 45 Semiconductor chip (semiconductor element)
6, 66 Substrate 7, 67 Conductive material 10 Sealing sheet 11, 41 Dicing tape 20, 60 Semiconductor device 31a, 31b Imaging device 32a, 32b Illumination L Oblique light α Incident angle of oblique light

Claims (11)

A method of manufacturing a semiconductor device comprising: an adherend; a semiconductor element electrically connected to the adherend; and an underfill material that fills a space between the adherend and the semiconductor element. ,
The exposed surface of the underfill material having a total light transmittance of 50% or more bonded to the circuit surface of the semiconductor element is irradiated with oblique light, and the relative position between the semiconductor element and the adherend is determined as the connection position of each other. A position aligning process for aligning with
A connection step of electrically connecting the semiconductor element and the adherend through the connection member while filling a space between the adherend and the semiconductor element with the underfill material. Production method.   The method of manufacturing a semiconductor device according to claim 1, wherein oblique light is irradiated at an incident angle of 5 to 85 ° with respect to an exposed surface of the underfill material.   The method of manufacturing a semiconductor device according to claim 1, wherein the oblique light includes a wavelength of 400 to 550 nm.   The method for manufacturing a semiconductor device according to claim 1, wherein the oblique light is irradiated from two or more directions or all directions with respect to the exposed surface of the underfill material.   The method for manufacturing a semiconductor device according to claim 1, wherein the underfill material includes an inorganic filler.   The method for manufacturing a semiconductor device according to claim 5, wherein the inorganic filler has an average particle diameter of 0.005 to 10 μm.   The method for manufacturing a semiconductor device according to claim 1, wherein the underfill material includes a thermoplastic resin and a thermosetting resin. An underfill material for disposing in a space between the adherend and the semiconductor element in a semiconductor device in which a semiconductor element is mounted on the adherend,
An inorganic filler having a surface treatment and an average particle size of 0.1 μm or less;
A thermosetting resin;
A thermoplastic resin;
An underfill material containing a curing accelerating catalyst.   The underfill material according to claim 8, wherein the surface treatment is a treatment with a silane coupling agent.   The underfill material according to claim 8 or 9, wherein the inorganic filler is a silica filler. The underfill material according to any one of claims 8 to 10, wherein a content of the inorganic filler is 70% by weight or less.

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