JP2009238770A - Dicing tape, dicing tape integrated type adhesive sheet, and manufacturing method of semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dicing tape can cut an adhesive sheet along with a semiconductor wafer at the same time in cutting conditions of the adhesive sheet and the semiconductor wafer normally executed; a dicing tape integration type adhesive sheet; and a manufacturing method of a semiconductor device using them. <P>SOLUTION: This dicing tape is used for this manufacturing method of a semiconductor device including a process (IV) of providing a plurality of segmented semiconductor chips with adhesive tapes by cutting the adhesive tapes, and characterized in that a yield point is not shown in tensile deformation of the dicing tape, and adhesive force between the dicing tape and the adhesive sheet is 20-100 N/m in the process (IV). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a dicing tape, a dicing tape integrated adhesive sheet, and a method for manufacturing a semiconductor device.

  Currently, as a manufacturing method of semiconductor manufacturing, a semiconductor wafer back surface attaching method in which an adhesive sheet and a dicing tape are attached to the back surface of a semiconductor wafer, and then a part of the semiconductor wafer, the adhesive sheet, and the dicing tape is cut in a dicing process is generally used. It is used for. As an example of this, a method has been proposed in which an adhesive sheet is attached on a dicing tape and this is attached to a semiconductor wafer (see, for example, Patent Documents 1 to 4).

  In this manufacturing method of the semiconductor wafer back surface pasting method, it is necessary to cut the adhesive sheet at the same time when dicing the semiconductor wafer. However, in a general dicing method using a diamond blade, the semiconductor wafer and the adhesive sheet are simultaneously cut. In order to do so, it was necessary to slow down the cutting speed, leading to an increase in cost.

  In recent years, the number of stacked chips in a package has increased for the purpose of increasing the storage capacity per package. Accordingly, the thickness of the chip or the semiconductor wafer is reduced by a back grinding process or the like, and a semiconductor wafer having a thickness of 20 to 30 μm is produced. As the semiconductor wafer becomes thinner, the semiconductor wafer is more likely to be broken during dicing, so that the production efficiency is greatly deteriorated, and the above problem is becoming more serious.

On the other hand, as a method for dividing the semiconductor wafer, a method of processing a groove to be a crease without completely cutting the semiconductor wafer, or a modified region is formed by irradiating a laser beam inside the semiconductor wafer on the line to be cut. In recent years, a method of cutting a semiconductor wafer, such as a method, by performing a process of easily separating the semiconductor wafer and then applying an external force has been proposed. The former method is called half-cut dicing, and the latter method is called stealth dicing (see, for example, Patent Documents 5 and 6). These methods have the effect of reducing defects such as chipping, particularly when the thickness of the semiconductor wafer is thin, and since a kerf width is not required, an improvement in yield can be expected.
JP 2002-226996 A JP 2002-158276 A JP-A-2-32181 International Publication No. 2004/109786 Pamphlet JP 2002-192370 A JP 2003-338467 A

  Here, in order to manufacture a semiconductor device by the semiconductor wafer back surface bonding method using the above-described half-cut dicing or stealth dicing, it is necessary to cut the adhesive sheet simultaneously with the semiconductor wafer. When a dicing tape is used, it is difficult to cut the adhesive sheet simultaneously with the semiconductor wafer.

  Accordingly, the present invention provides a dicing tape, a dicing tape-integrated adhesive sheet that can cut the adhesive sheet simultaneously with the semiconductor wafer, and a method of manufacturing a semiconductor device using the same under the usual cutting conditions of the adhesive sheet and the semiconductor wafer. The purpose is to provide.

The present invention is characterized by the following items <1> to <9>.
<1> I) A process of attaching an adhesive sheet to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
III) A step of attaching a dicing tape to the adhesive sheet;
In the order of Step I) -Step II) -Step III), Step II) -Step I) -Step III), or Step I) -Step III) -Step II),
IV) A step of obtaining a plurality of separated semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding a semiconductor chip with an adhesive sheet to a semiconductor chip mounting support member;
A dicing tape for use in a method of manufacturing a semiconductor device,
A dicing tape characterized in that it does not show a yield point when the dicing tape is subjected to tensile deformation, and the adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less.
<2> The dicing tape according to <1>, wherein the dicing tape is composed of an adhesive layer and a base material layer, and the base material layer is a layer composed of a polyvinyl chloride base material.
<3> The dicing tape is composed of a pressure-sensitive adhesive layer and a base material layer, and the base material layer is a layer made of a base material made of a polymer obtained by copolymerizing polyethylene, polypropylene, or a monomer containing no chlorine < The dicing tape according to 1>.

<4> I ′) A step of attaching a dicing tape integrated adhesive sheet in which an adhesive sheet and a dicing tape are laminated to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
In the order of step I ′)-step II) or step II) -step I ′),
IV) A step of obtaining a plurality of separated semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding a semiconductor chip with an adhesive sheet to a semiconductor chip mounting support member;
A dicing tape-integrated adhesive sheet used in a method for manufacturing a semiconductor device,
A dicing tape-integrated adhesive sheet characterized in that it does not show a yield point during tensile deformation of the dicing tape, and the adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less.
<5> The dicing tape-integrated adhesive sheet according to <4>, wherein the dicing tape comprises a pressure-sensitive adhesive layer and a base material layer, and the base material layer comprises a polyvinyl chloride base material.
<6> The dicing tape is composed of a pressure-sensitive adhesive layer and a base material layer, and the base material layer is a layer made of a base material made of a polymer obtained by copolymerizing polyethylene, polypropylene, or a monomer containing no chlorine < The dicing tape-integrated adhesive sheet according to 4>.

<7> I) A process of attaching an adhesive sheet to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
III) A step of attaching a dicing tape to the adhesive sheet;
In the order of Step I) -Step II) -Step III), Step II) -Step I) -Step III), or Step I) -Step III) -Step II),
IV) A step of obtaining a plurality of separated semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding a semiconductor chip with an adhesive sheet to a semiconductor chip mounting support member;
A method for manufacturing a semiconductor device comprising:
A method for manufacturing a semiconductor device, characterized in that it does not show a yield point during tensile deformation of a dicing tape, and the adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less.
<8> I ′) A step of attaching a dicing tape integrated adhesive sheet in which an adhesive sheet and a dicing tape are laminated to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
In the order of step I ′)-step II) or step II) -step I ′),
IV) A step of obtaining a plurality of separated semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding a semiconductor chip with an adhesive sheet to a semiconductor chip mounting support member;
A method for manufacturing a semiconductor device comprising:
A method for manufacturing a semiconductor device, characterized in that it does not show a yield point during tensile deformation of a dicing tape, and the adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less.
<9> The method for manufacturing a semiconductor device according to <7> or <8>, wherein the method for dividing the semiconductor wafer is half-cut dicing or stealth dicing.

  ADVANTAGE OF THE INVENTION According to this invention, the dicing tape which can cut | disconnect an adhesive sheet simultaneously with a semiconductor wafer on the cutting conditions of the adhesive sheet and semiconductor wafer performed normally, a dicing tape integrated adhesive sheet, and manufacture of a semiconductor device using these A method is provided.

  The dicing tape of the present invention does not show a yield point during tensile deformation of the dicing tape, and in the step IV), the adhesive force between the dicing tape and the adhesive sheet is 20 N / m or more and 100 N / m or less. . As seen in the load-elongation diagram, stress-strain diagram, etc., when the stress acting on the object exceeds the elastic limit, the phenomenon in which the deformation gradually progresses without an increase in load or stress is called "yield". The point at the maximum load and maximum stress value of the elastic behavior is called the “yield point”.

  The dicing tape having a yield point is a strip-shaped dicing tape subjected to a tensile test at 25 ° C., and when the strain is plotted on the X axis and the elongation is plotted on the Y axis, the slope dX / dY is 0 from a positive value. It takes a stress value that changes to a negative value. In the tape having such a yield point, in the step of cutting the semiconductor wafer and the adhesive sheet by applying an external force to the dicing tape (step IV above), the semiconductor wafer is not stressed and only the peripheral dicing tape is stretched. Due to the deformation, there is a problem that the semiconductor wafer does not break or a crack remains. When there is no yield point, the external force is easily applied to the semiconductor wafer and the adhesive sheet, and the breakability is good.

  Examples of such dicing tape include polytetrafluoroethylene film, polyethylene terephthalate film, film made of polyvinyl acetate polyethylene copolymer, polyethylene film, polypropylene film, polymethylpentene film, plastic film such as polyvinyl chloride, and the like. A tape in which a base layer composed of laminated films and the like and a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive mainly composed of acrylic rubber, urethane resin, silicone resin and the like are laminated.

  In particular, the material of the substrate layer is preferably polyvinyl chloride or polyvinyl acetate polyethylene copolymer because it has no yield point, is excellent in elongation at low temperature, and has low anisotropy in film elongation. The film tends to be oriented in the vertical direction during extrusion molding, and the elongation of the film may not be completely uniform with respect to the above film, but it is preferable to adjust it by adjusting the tension during wafer lamination. Further, surface treatment such as primer coating, UV treatment, corona discharge treatment, polishing treatment and etching treatment may be performed as necessary. The pressure-sensitive adhesive layer can be formed by applying and drying a resin composition having an appropriate tack strength obtained by adjusting the ratio of the liquid component and the Tg of the high molecular weight component on the base material layer.

  Further, the film thickness of the dicing tape is not particularly limited, and is appropriately determined based on the knowledge of a person skilled in the art depending on the film thickness of the adhesive sheet and the application of the dicing tape-integrated adhesive sheet. The film has a handleability of 60 to 150 μm, preferably 70 to 130 μm.

  The dicing tape is bonded to the adhesive sheet on the pressure-sensitive adhesive layer surface, and the adhesive strength by a 90 ° peeling test between the dicing tape and the adhesive sheet is 20 N / m or more and 100 N / m or less. Adhesive strength of 20 N / m or more and 100 N / m is preferable in that the dicing tape and the adhesive sheet are not peeled off during expansion, and the adhesive sheet is easily broken as a result, and further chips can be picked up later. .

  When the adhesive force is less than 20 N / m, when the dicing tape is stretched, the semiconductor wafer is broken, the internal stress is released when it becomes a chip, the interface between the chip and the dicing tape peels off, and warping occurs. Picking up becomes difficult. If the adhesive strength is more than 100 N / m, picking up is difficult, and chip cracking or the like occurs.

  The adhesive sheet used in the present invention preferably contains at least a high molecular weight component. For example, HS-230, HS-270, HS-260, etc. manufactured by Hitachi Chemical Co., Ltd. may be used. it can.

  When an adhesive sheet having a high breaking strength and elongation at break is used before being attached to the semiconductor wafer, the adhesive sheet can be attached to the semiconductor wafer at a low temperature, and the breaking strength and elongation at break are as described above. Breakability can be improved by making it within the numerical range. The adhesive sheet is preferably laminated to the wafer at 40 to 100 ° C. in order to reduce the warpage of the semiconductor wafer and improve the handleability at room temperature. The adhesive sheet preferably has an elastic modulus of 0.1 to 20 MPa, more preferably 0.1 to 10 MPa, as measured by dynamic viscoelasticity at 60 Hz of an adhesive sheet in a B-stage state at 10 Hz. It is particularly preferably 1 to 5 MPa. If the pressure is less than 0.1 MPa, the sheet tends to peel off or shift from the semiconductor wafer after sticking.

  In addition to the above properties, the adhesive sheet preferably has heat resistance and moisture resistance required when a semiconductor element is mounted on a semiconductor element mounting support member. The adhesive sheet is not particularly limited as long as it satisfies the above characteristics, but has an appropriate tack strength and good handleability in the form of a sheet. It is preferable that a component and a filler are included, and besides these, a curing accelerator, a catalyst, an additive, a coupling agent, and the like may be included. Moreover, there exists a tendency for breaking strength and breaking elongation to become so high that there are many high molecular weight components contained in an adhesive sheet, and there are few fillers.

  Next, components constituting the adhesive sheet will be described in more detail.

  The adhesive sheet preferably contains a high molecular weight component in order to improve tackiness and film strength, and has a glass transition temperature (hereinafter referred to as Tg) of -30 ° C to 50 ° C and a weight average molecular weight of 50,000 to 1,000,000. It is preferable. When Tg exceeds 50 ° C., it is inconvenient in that the flexibility of the sheet is low, and when Tg is less than −30 ° C., since the flexibility of the sheet is too high, the sheet is difficult to break when the semiconductor wafer breaks. Inconvenient. Further, if the weight average molecular weight is less than 50,000, it is disadvantageous in that the heat resistance of the sheet is lowered, and if the molecular weight exceeds 1,000,000, it is disadvantageous in that the fluidity of the sheet is lowered.

  From the viewpoints of breakability and heat resistance of the adhesive sheet when cutting a semiconductor wafer, a high molecular weight component having a Tg of −20 ° C. to 40 ° C. and a weight average molecular weight of 100,000 to 900,000 is more preferable, and the Tg of −10 ° C. to 50 ° C. A high molecular weight component having a weight average molecular weight of 50,000 to 1,000,000 at C is preferred, and a high molecular weight component having a Tg of -10 to 30 ° C. and a weight average molecular weight of 500,000 to 900,000 is particularly preferred. The weight average molecular weight is a polystyrene conversion value using a standard polystyrene calibration curve in gel permeation chromatography (GPC), L-6000 manufactured by Hitachi, Ltd. is used as a pump, and Hitachi Chemical Co., Ltd. is used as a column. ) Gelpack GL-R440, Gelpack GL-R450, and Gelpack GL-R400M (each 10.7 mmφ × 300 mm) connected in this order were used, tetrahydrofuran was used as the eluent, and 120 mg of sample was added to 5 ml of THF. The sample dissolved in can be measured at a flow rate of 1.75 mL / min.

  Specific examples of the high molecular weight component include polyimide, polystyrene, polyethylene, polyester, polyamide, butadiene rubber, acrylic rubber, (meth) acrylic resin, urethane resin, polyphenylene ether resin, polyetherimide resin, phenoxy resin, and modified polyphenylene ether. Examples thereof include resins, phenoxy resins, polycarbonates, and mixtures thereof. In particular, a high molecular weight component containing a functional monomer having a weight average molecular weight of 100,000 or more, for example, a functional monomer such as glycidyl acrylate or glycidyl methacrylate, and an epoxy group containing a weight average molecular weight of 100,000 or more ( A (meth) acrylic copolymer is preferred. As the epoxy group-containing (meth) acrylic copolymer, for example, (meth) acrylic ester copolymer, acrylic rubber and the like can be used, and acrylic rubber is more preferable. The acrylic rubber is a rubber mainly composed of an acrylate ester and mainly composed of a copolymer such as butyl acrylate and acrylonitrile, a copolymer such as ethyl acrylate and acrylonitrile, or the like.

  In addition, the adhesive sheet preferably contains a thermosetting component, and as such, there are an epoxy resin, a cyanate resin, a phenol resin and a curing agent thereof, and an epoxy resin is preferable in terms of high heat resistance. . The epoxy resin is not particularly limited as long as it is cured and has an adhesive action. Bifunctional epoxy resins such as bisphenol A type epoxy, novolac type epoxy resins such as phenol novolac type epoxy resin and cresol novolac type epoxy resin, and the like can be used. Moreover, what is generally known, such as a polyfunctional epoxy resin, a glycidyl amine type epoxy resin, a heterocyclic ring-containing epoxy resin, or an alicyclic epoxy resin, can be applied.

  Furthermore, the adhesive sheet has the purpose of reducing the breaking strength and breaking elongation of the adhesive sheet in the B-stage state, improving the handling of the adhesive, improving the thermal conductivity, adjusting the melt viscosity, and imparting thixotropic properties. It is preferable to blend a filler, preferably an inorganic filler.

  As the inorganic filler, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, aluminum nitride, aluminum borate whisker, boron nitride, crystalline silica, Examples thereof include amorphous silica and antimony oxide. In order to improve thermal conductivity, alumina, aluminum nitride, boron nitride, crystalline silica, amorphous silica and the like are preferable. For the purpose of adjusting melt viscosity and imparting thixotropic properties, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, crystalline silica, non-crystalline silica Crystalline silica and the like are preferred. In order to improve moisture resistance, alumina, silica, aluminum hydroxide, and antimony oxide are preferable.

The amount of the filler is preferably 5% by weight or more and 70% by weight or less, more preferably 35% by weight or more and 60% by weight or less with respect to the total weight of the adhesive sheet. When the blending amount increases, problems such as an increase in storage elastic modulus of the adhesive sheet, a decrease in adhesiveness, and a decrease in electrical characteristics due to remaining voids are likely to occur. Moreover, it is preferable that the specific gravity of a filler is 1-10 g / cm < ³ >.

  The adhesive sheet is prepared by mixing a high molecular weight component and, if necessary, a thermosetting component, a filler, and other components in an organic solvent and kneading to prepare a varnish, and then forming the varnish layer on the base film. After forming and heat-drying, it can be obtained by removing the substrate.

  The above mixing and kneading can be carried out by appropriately combining dispersers such as ordinary stirrers, crackers, three rolls, and ball mills. The heating and drying conditions are not particularly limited as long as the used solvent is sufficiently volatilized, but the heating is usually performed at 60 to 200 ° C. for 0.1 to 90 minutes.

  The organic solvent used for the preparation of the varnish in the production of the adhesive sheet is not limited as long as it can uniformly dissolve, knead or disperse the material, and a conventionally known one can be used. Examples of such a solvent include ketone solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, acetone, methyl ethyl ketone, and cyclohexanone, toluene, xylene, and the like. It is preferable to use methyl ethyl ketone, cyclohexanone, etc. in terms of fast drying speed and low price.

  The amount of the organic solvent used is not particularly limited as long as the residual volatile content after production of the adhesive sheet is 0.01 to 3% by weight based on the total weight, but from the viewpoint of heat resistance reliability, 0.01% based on the total weight. -2.0 wt% is preferable, and 0.01-1.5 wt% is more preferable based on the total weight.

  In addition, a plurality of adhesive sheets may be stacked to form a multilayer adhesive sheet as long as it can be cut. Alternatively, the adhesive sheet and a film made of, for example, a thermoplastic film, a pressure-sensitive adhesive, a thermosetting resin, or the like may be combined, and the adhesive sheet may be superimposed on both sides of the film to form a multilayer adhesive sheet. In addition, the range which can be cut | disconnected means that the breaking strength of a multilayered adhesive sheet, breaking elongation, and an elasticity modulus exist in the said numerical range. Examples of such a film include films made of thermoplastic resins such as polyimide and polyester, epoxy resins, silicone resins, and mixtures thereof. These films may contain various fillers.

  Although there is no restriction | limiting in particular in the film thickness of an adhesive sheet, 1-250 micrometers is preferable. If it is thinner than 1 μm, the stress relaxation effect and adhesiveness tend to be poor, and if it is thicker than 250 μm, it is not economical, and it tends to be difficult to break because it cannot meet the demand for miniaturization of semiconductor devices. In addition, 3-100 micrometers is preferable at the point which has high adhesiveness and a semiconductor device can be reduced in thickness, More preferably, it is 5-55 micrometers.

  The dicing tape-integrated adhesive sheet of the present invention can be obtained by laminating the adhesive sheet on the pressure-sensitive adhesive layer surface of the dicing tape described above. By using this dicing tape-integrated adhesive sheet, the laminating process on the semiconductor wafer can be performed only once, and the work efficiency can be improved. As a method of laminating the adhesive sheet on the dicing tape, in addition to printing, a pre-made adhesive sheet can be pressed on the dicing tape and a hot roll laminating method. However, it can be continuously manufactured and is hot in terms of efficiency. A roll laminating method is preferred.

The method for manufacturing a semiconductor device of the present invention uses the dicing tape of the present invention described above,
I) a process of attaching an adhesive sheet to a semiconductor wafer (process I)),
II) a step of dividing the semiconductor wafer (step II)),
III) A step of attaching a dicing tape to the adhesive sheet (step III)),
In the order of Step I) -Step II) -Step III), Step II) -Step I) -Step III), or Step I) -Step III) -Step II),
IV) Step of obtaining a plurality of individual semiconductor chips with an adhesive sheet by cutting the adhesive sheet (Step IV)),
V) a step of bonding a semiconductor chip with an adhesive sheet to a semiconductor chip mounting support member (step V)). A preferred embodiment of a method for manufacturing a semiconductor device according to the present invention will be described below with reference to FIGS.

  FIG. 1 shows a step of attaching the adhesive sheet 1 to the semiconductor wafer A (step I), and FIG. 2 shows a modification of the inside of the wafer by irradiating the cutting line 4 of the semiconductor wafer A with laser light. A step (step II)) in which the region (scheduled portion) 5 is formed and the semiconductor wafer A is separated (step II) is shown in FIG. 4 is a step of cutting the semiconductor wafer A and the adhesive sheet 1 by expanding the dicing tape 2 (step IV)), and FIG. 5 is attached with an adhesive sheet. The process of bonding the semiconductor chip 6 to the semiconductor chip mounting support member 7 (process V)) is shown respectively.

  As the semiconductor wafer, in addition to single crystal silicon, polycrystalline silicon, various ceramics, compound semiconductors such as gallium arsenide, and the like are used.

  The temperature at which the adhesive sheet 1 in step I) is attached to the semiconductor wafer A, that is, the lamination temperature is preferably in the range of 0 ° C. to 170 ° C. In order to reduce the warpage of the semiconductor wafer A, 20 ° C. to 130 ° C. More preferably, it is in the range of ° C, and particularly preferably in the range of 20 ° C to 80 ° C. Further, when the step I) is performed after the step II), in order to prevent the semiconductor wafer A from being broken due to stress or deformation in the laminating step, the semiconductor wafer A is supported and laminated so as not to be deformed. preferable.

  As a processing method for dividing the semiconductor wafer A in the above step II), a method of processing a groove to be a crease without completely cutting the semiconductor wafer A with a dicing cutter or the like, or inside the semiconductor wafer A on the planned cutting line Examples thereof include a method of forming a modified region by irradiating a laser beam, and a method of easily cutting the semiconductor wafer A by applying an external force or the like thereafter. In addition, about the laser processing method of the semiconductor wafer A, the method of Unexamined-Japanese-Patent No. 2002-192370 and Unexamined-Japanese-Patent No. 2003-338467 can be used. As for the apparatus, for example, MAHODICING MACHINE made by Tokyo Seimitsu Co., Ltd. can be used. It should be noted that using these methods to classify semiconductor wafers means that the semiconductor wafer is almost cut and only partly connected by applying an external force after this condition has been created in advance so that it can be cut by external force. The semiconductor wafer is cut by applying an external force, but is in contact with each other, or in a state adjacent to each other with a slight gap of several μm or less, or the semiconductor wafer is cut by applying an external force, and several μm or more It refers to the state adjacent to each other with a gap of 1 mm or less. In addition, when the semiconductor wafer and the adhesive sheet are cut, when the semiconductor wafer is not completely cut, both are cut at the same time. Also indicates that it is disconnected.

  The laser beam to the semiconductor wafer A may be irradiated from the front surface of the semiconductor wafer A, that is, the surface on which the circuit is formed, or the back surface of the semiconductor wafer A, that is, the adhesive sheet on which the circuit is not formed. You may irradiate from the surface of the side to stick. When the step II) is performed after the step I) or the step I ′) or the step III) described later, the semiconductor wafer A can be irradiated with laser light from the adhesive sheet 1 or the dicing tape 2 side. Therefore, it is preferable to use the adhesive sheet 1 or the dicing tape 2 that transmits laser light. Moreover, it is preferable that the adhesive sheet 1 is different from the dicing tape 2 in transparency and color tone in that it is easy to recognize a broken portion, that is, a portion that could not be cut.

  In step II), for example, a laser beam is focused from the surface side of the semiconductor wafer A along the planned cutting line 4 by using the above-described laser processing apparatus to align the focal point inside the semiconductor wafer A under the following conditions. The modified region 5 is formed inside the semiconductor wafer A. With this modified region 5, the semiconductor wafer A can be cut along the planned cutting line. The modified region 5 is preferably a melt-processed region formed by locally heating and melting the inside of the semiconductor wafer by multiphoton absorption.

(Laser processing conditions)
(A) Semiconductor substrate (semiconductor wafer): silicon wafer (thickness 350 μm, outer diameter 6 inches)
(B) Laser light source: semiconductor laser excitation Nd: YAG laser wavelength: 1064 nm
Laser light spot cross-sectional area: 3.14 × 10 ⁻⁸ cm ²
Oscillation form: Q switch pulse repetition frequency: 100 kHz
Pulse width: 30ns
Output: 20 μJ / pulse laser light quality: TEM00
Polarization characteristics: Linearly polarized light (C) Condensing lens magnification: 50 times NA: 0.55
Transmittance to laser light wavelength: 60% (D) Moving speed of mounting table on which semiconductor substrate is mounted: 100 mm / second

  In step III), the dicing tape 2 may be attached to the surface of the adhesive sheet 1 opposite to the surface on which the semiconductor wafer A is attached by a conventionally known method. The affixing temperature, that is, the laminating temperature is preferably performed in the range of 0 ° C to 60 ° C, more preferably in the range of 10 ° C to 40 ° C, and preferably in the range of 15 ° C to 30 ° C. Further preferred. When step III) is performed after step II), it is preferable to perform the lamination while supporting the semiconductor wafer A so as not to be deformed in order to prevent the semiconductor wafer A from being broken due to stress or deformation in the laminating step.

  The manufacturing method of the semiconductor device of the present invention may include a dicing tape-integrated adhesive sheet instead of the dicing tape, and may include a step I ′) described later instead of the steps I) and III).

That is, the manufacturing method of the semiconductor device of the present invention uses the above-described dicing tape integrated adhesive sheet of the present invention,
I ′) a step of attaching a dicing tape integrated adhesive sheet in which an adhesive sheet and a dicing tape are laminated to a semiconductor wafer (step I ′)),
II) a step of dividing the semiconductor wafer (step II)),
In the order of step I ′)-step II) or step II) -step I ′),
IV) Step of obtaining a plurality of individual semiconductor chips with an adhesive sheet by cutting the adhesive sheet (Step IV)),
V) a step of bonding a semiconductor chip with an adhesive sheet to a semiconductor chip mounting support member (step V));
May be provided. Hereinafter, another preferred embodiment of the method for manufacturing a semiconductor device of the present invention will be described with reference to FIGS.

  FIG. 6 shows a process of attaching the dicing tape-integrated adhesive sheet 3 to the semiconductor wafer A (process I ′). FIG. 7 shows a process of dividing the semiconductor wafer A by half-cutting with the dicing saw 23 (process). FIG. 8 shows a state in which the semiconductor wafer A and the adhesive sheet 1 are cut through the step of applying an external force to the dicing tape-integrated adhesive sheet 3 (step IV)), and FIG. The process of bonding the semiconductor chip 6 with a sheet to the semiconductor chip mounting support member 7 (process V)) is shown respectively.

  Further, FIG. 10 shows a process of attaching the dicing tape-integrated adhesive sheet 3 to the semiconductor wafer A, irradiating a laser beam on the planned cutting line of the semiconductor wafer A, and modifying the region (scheduled cutting portion) inside the semiconductor wafer. ) 5 and forming a semiconductor wafer, and a step of cutting the semiconductor wafer A and the adhesive sheet 1 by applying an external force to the dicing tape 2 or the dicing tape-integrated adhesive sheet 3.

  In the method of manufacturing a semiconductor device according to the present invention, the combination of the method of attaching the adhesive sheet 1 and the dicing tape 2 to the semiconductor wafer A and the dicing method are not particularly limited. From the viewpoint of workability and efficiency, it is most preferable that the dicing tape-integrated adhesive sheet 3 is attached to the semiconductor wafer A and stealth dicing is performed.

  In the step I), when the dicing tape-integrated adhesive sheet 3 is affixed to the semiconductor wafer A, it is affixed so that the surface of the adhesive sheet 1 in the semiconductor wafer A and the dicing tape-integrated adhesive sheet 3 is in contact. The affixing temperature, that is, the laminating temperature is preferably in the range of 0 ° C. to 170 ° C., and in order to reduce the warp of the semiconductor wafer A, it is more preferably in the range of 20 ° C. to 130 ° C., and 20 ° C. to A range of 60 ° C. is particularly preferable.

  After step I), II) and III) or step I ′) and II), step IV) is performed. In this step, the semiconductor wafer A and the adhesive sheet 1 are cut by dicing tape 2 or dicing tape. This can be done by applying an external force to the integrated adhesive sheet 3. For example, in the case of half-cut dicing, this external force is preferably applied in the bending direction or twist direction, and in the case of stealth dicing, it is preferably applied in the pulling (expanding) direction.

  For example, in stealth dicing, when the semiconductor wafer A and the adhesive sheet 1 are cut by pulling both ends of the dicing tape 2 and applying an external force, it can be performed by a commercially available wafer expanding apparatus. More specifically, as shown in FIG. 4, the ring 11 is affixed to and fixed to the periphery of the dicing tape 2 disposed on the stage 13, and then the push-up portion 12 is lifted, so that both ends are attached to the dicing tape 2. Apply tension from.

  In this invention, the expanding speed is preferably 10 to 1000 mm / sec, and the expanding speed is defined as the expanding speed, and the height 14 at which the thrusting section is increased is defined as the expanding amount. The second is more preferable, and 50 to 150 mm / second is particularly preferable. Further, the amount of expand is preferably 5 to 30 mm, more preferably 10 to 30 mm, and particularly preferably 15 to 20 mm. When the expanding speed is less than 10 mm / second, cutting of the semiconductor wafer and the adhesive sheet tends to be difficult, and when it exceeds 1000 mm / second, the dicing tape tends to break. Moreover, if the amount of expand is less than 5 mm, the semiconductor wafer and the adhesive sheet tend to be difficult to cut, and if it exceeds 30 mm, the dicing tape tends to break.

  By pulling the dicing tape 2 and applying an external force in this way, a crack occurs in the thickness direction of the semiconductor wafer A starting from the modified region inside the semiconductor wafer A. Reaches the back surface of the adhesive sheet 1 in close contact with the semiconductor wafer A, and the semiconductor wafer A and the adhesive sheet 1 are broken, that is, cut. Thereby, a semiconductor chip with an adhesive sheet can be obtained.

  In addition, when the amount of expand exceeds 25 mm, it is preferable to use a vinyl chloride base material as the base material layer of the dicing tape 2, but when the amount of pulling is small, it is preferable to use various polyolefin base materials. . Moreover, although it is preferable to perform an expansion at room temperature, you may adjust between -50 degreeC-100 degreeC as needed. In this invention, since the elongation at break of an adhesive sheet is small and it is easy to cut | disconnect, it is preferable at the point which prevents the yield fall by the cutting defect of an adhesive sheet. The expanding step may be carried out at room temperature, but cooling to 10 ° C. or lower is preferable in that the die bond film becomes brittle and breakability is improved, more preferably 0 ° C. or lower, more preferably −10 ° C. or lower. On the other hand, when the temperature is −50 ° C. or lower, there is a problem that dew condensation is remarkable, the elongation of the dicing tape 2 is reduced, and the adhesive of the dicing tape 2 becomes hard, causing cracks during expansion and uneven spreading. There is a tendency.

  When a UV curable pressure sensitive adhesive is used for the pressure sensitive adhesive layer of the dicing tape 2, UV light is irradiated from the side opposite to the surface where the semiconductor wafer A is attached to the dicing tape 2 before or after the expansion. Cure the adhesive. As a result, the adhesive force between the UV curable pressure-sensitive adhesive and the adhesive sheet is reduced, and pickup in the subsequent step V) is facilitated.

  Subsequently, in step V), a plurality of separated semiconductor chips with an adhesive sheet are picked up using a suction collet 21, a needle rod 22 or the like as shown in FIGS. The adhesive sheet is heated and cured by placing it on the semiconductor chip mounting portion of the chip mounting support member. Heat curing is normally performed between 100-220 degreeC.

  The method for manufacturing a semiconductor device in the present invention is not limited to the above steps, and may include arbitrary steps. For example, after performing step I) or step I ′) and before performing step IV), the step of irradiating the adhesive sheet with ultraviolet rays, infrared rays or microwaves, or heating or cooling the adhesive sheet The process of carrying out may be included. After performing step V), a wire bonding step, a sealing step, and the like are included as necessary.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited to these.

[Dicing tape integrated adhesive sheet]
Example 1
HS-270 (thickness 20 μm) manufactured by Hitachi Chemical Co., Ltd. was used for the adhesive sheet. This adhesive sheet is laminated on the pressure-sensitive adhesive layer surface of a dicing tape (base material thickness 100 μm, pressure-sensitive adhesive thickness 10 μm) in which an acrylic pressure-sensitive adhesive is applied to a polyvinyl chloride base material, and dicing tape integrated adhesion in Example 1 A sheet was obtained.

(Example 2)
HS-270 (thickness 20 μm) manufactured by Hitachi Chemical Co., Ltd. was used for the adhesive sheet. The adhesive sheet was laminated on the pressure-sensitive adhesive layer surface of a dicing tape (base material thickness: 100 μm, pressure-sensitive adhesive thickness: 10 μm) in which an acrylic pressure-sensitive adhesive was applied to an ethylene vinyl acetate copolymer film base material, and the dicing of Example 2 was performed. A tape-integrated adhesive sheet was obtained.

(Comparative Example 1)
HS-270 (thickness 20 μm) manufactured by Hitachi Chemical Co., Ltd. was used for the adhesive sheet. This adhesive sheet was laminated on the pressure-sensitive adhesive layer surface of a dicing tape (base material thickness 100 μm, pressure-sensitive adhesive thickness 10 μm) obtained by applying an acrylic pressure-sensitive adhesive to a polyethylene film base material prepared by a high pressure polymerization method. A dicing tape integrated adhesive sheet was obtained.

[Evaluation of dicing tape]
The dicing tapes of Examples 1 and 2 and Comparative Example 1 were each formed into a strip shape, and the obtained strip-shaped dicing tape was subjected to a tensile test at 25 ° C. When the strain is plotted on the X-axis and the elongation is plotted on the Y-axis, the stress value where the slope dx / dY changes from a positive value to 0 or a negative value is regarded as having a yield point. Those not taken were evaluated as having no yield point. The evaluation results are shown in Table 1.

[Evaluation of adhesive strength]
The dicing tape-integrated adhesive sheets obtained in Examples 1 and 2 and Comparative Example 1 were subjected to a 90 ° peel test, and the adhesive strength was measured. The measurement results are shown in Table 1.

[Production of semiconductor chip with adhesive sheet by stealth dicing]
Using the dicing tape-integrated adhesive sheets obtained in Examples 1 and 2 and Comparative Example 1, a semiconductor chip with an adhesive sheet was produced by the method shown in Step 1 below, and its breakability was evaluated. The evaluation results are shown in Table 1.

(Process 1)
The semiconductor wafer with the adhesive sheet was irradiated with laser light as shown in FIG. 2 to form a modified region inside the semiconductor wafer. Next, using the hot roll laminator (DuPont Riston) on the semiconductor wafer (thickness 80 μm) so that the semiconductor wafer and the adhesive sheet are in contact with each other, the dicing tape integrated adhesive sheets of Examples 1 and 2 and Comparative Example 1 are 60 Laminated at ℃. A stainless steel ring was attached to the outer periphery of the dicing tape.
Subsequently, the ring was fixed and the dicing tape was expanded by an expanding device, thereby producing a 5 mm square chip. The expanding conditions were an expanding speed of 30 mm / expand and an expanding amount of 15 mm. At that time, the semiconductor wafer and the adhesive sheet that were simultaneously cut 90% or more were evaluated as ◯ (good breakability), and less than 90% were evaluated as x (defective).

It is a conceptual diagram which shows suitable one Embodiment of the process I) in this invention. It is a conceptual diagram which shows suitable one Embodiment of the process II) in this invention. It is a conceptual diagram which shows suitable one Embodiment of the process III) in this invention. It is a conceptual diagram which shows suitable one Embodiment of the process IV) in this invention. It is a conceptual diagram which shows suitable one Embodiment of the process V) in this invention. It is a conceptual diagram which shows other suitable embodiment of process I ') in this invention. It is a conceptual diagram which shows suitable one Embodiment of the process II) in this invention. It is a conceptual diagram which shows the state by which the semiconductor wafer and the adhesive sheet after process IV) in this invention were cut | disconnected. It is a conceptual diagram which shows other suitable embodiment of the process V) in this invention. It is a conceptual diagram which shows one Embodiment of process I '), process II), and process IV) in this invention.

Explanation of symbols

A ... Semiconductor wafer, 1 ... Adhesive sheet, 2 ... Dicing tape, 2a ... Adhesive layer, 2b ... Base material layer, 3 ... Dicing tape integrated adhesive sheet, 4 ... Planned cutting line, 5 ... Modified region, 6 ... Semiconductor chip, 7 ... Semiconductor chip mounting support member, 11 ... Ring, 12 ... Push-up part, 13 ... Stage, 21 ... Adsorption collet, 22 ... Needle rod, 23 ... Dicing saw.

Claims (9)

I) a process of attaching an adhesive sheet to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
III) A step of attaching a dicing tape to the adhesive sheet;
In the order of Step I) -Step II) -Step III), Step II) -Step I) -Step III), or Step I) -Step III) -Step II),
IV) A step of obtaining a plurality of individual semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding the semiconductor chip with the adhesive sheet to a semiconductor chip mounting support member;
A dicing tape for use in a method of manufacturing a semiconductor device,
A dicing tape which does not show a yield point when the dicing tape is pulled and has an adhesive force between the dicing tape and the adhesive sheet in step IV) of 20 N / m or more and 100 N / m or less. The dicing tape comprises an adhesive layer and a base material layer,
2. The dicing tape according to claim 1, wherein the base material layer is a layer made of a polyvinyl chloride base material. The dicing tape comprises an adhesive layer and a base material layer,
2. The dicing tape according to claim 1, wherein the base material layer is a layer made of a base material made of a polymer obtained by copolymerizing polyethylene, polypropylene, or a monomer not containing chlorine. I ′) attaching a dicing tape integrated adhesive sheet in which an adhesive sheet and a dicing tape are laminated to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
In the order of step I ′)-step II) or step II) -step I ′),
IV) A step of obtaining a plurality of individual semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding the semiconductor chip with the adhesive sheet to a semiconductor chip mounting support member;
A dicing tape-integrated adhesive sheet used in a method for manufacturing a semiconductor device,
A dicing tape integrated type characterized in that it does not show a yield point during tensile deformation of the dicing tape, and an adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less. Adhesive sheet. The dicing tape comprises an adhesive layer and a base material layer,
The dicing tape-integrated adhesive sheet according to claim 4, wherein the base material layer is a layer made of a polyvinyl chloride base material. The dicing tape comprises an adhesive layer and a base material layer,
The dicing tape-integrated adhesive sheet according to claim 4, wherein the base material layer is a layer made of a base material made of a polymer obtained by copolymerizing polyethylene, polypropylene, or a monomer not containing chlorine. I) a process of attaching an adhesive sheet to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
III) A step of attaching a dicing tape to the adhesive sheet;
In the order of Step I) -Step II) -Step III), Step II) -Step I) -Step III), or Step I) -Step III) -Step II),
IV) A step of obtaining a plurality of individual semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding the semiconductor chip with the adhesive sheet to a semiconductor chip mounting support member;
A method for manufacturing a semiconductor device comprising:
Producing a semiconductor device characterized in that it does not show a yield point during tensile deformation of the dicing tape, and the adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less. Method. I ′) attaching a dicing tape integrated adhesive sheet in which an adhesive sheet and a dicing tape are laminated to a semiconductor wafer;
II) a step of dividing the semiconductor wafer;
In the order of step I ′)-step II) or step II) -step I ′),
IV) A step of obtaining a plurality of individual semiconductor chips with an adhesive sheet by cutting the adhesive sheet;
V) bonding the semiconductor chip with the adhesive sheet to a semiconductor chip mounting support member;
A method for manufacturing a semiconductor device comprising:
Producing a semiconductor device characterized in that it does not show a yield point during tensile deformation of the dicing tape, and the adhesive force between the dicing tape and the adhesive sheet in step IV) is 20 N / m or more and 100 N / m or less. Method. 9. The method of manufacturing a semiconductor device according to claim 7, wherein the method for dividing the semiconductor wafer is half-cut dicing or stealth dicing.

Images