JPWO2017110203A1 - Semiconductor processing tape - Google Patents

Abstract

  Provided is a semiconductor processing tape capable of preventing wrinkles from being generated in a metal layer during bonding to a semiconductor wafer. The semiconductor processing tape 10 of the present invention is a dicing tape 13 having a base film 11 and an adhesive layer 12, and a metal layer provided on the adhesive layer 12 for protecting the back surface of the semiconductor chip. 14 and an adhesive layer 15 for adhering the metal layer 14 to the back surface of the semiconductor chip, and the dicing tape 13 has a loop stiffness of 20 mN or more and less than 200 mN. It is characterized by being.

Description

  The present invention relates to a semiconductor processing tape, and more particularly to a semiconductor processing tape having a metal layer for protecting the back surface of a semiconductor chip mounted in a face-down manner.

  In recent years, there has been a further demand for thinner and smaller semiconductor devices and their packages. 2. Description of the Related Art Semiconductor devices are manufactured using a so-called face-down mounting method. The face-down method uses a semiconductor chip in which convex electrodes called bumps are formed on the circuit surface to ensure conduction, and the circuit surface is inverted (face-down) to connect the electrode to the substrate ( So-called flip chip connection).

  In such a semiconductor device, the back surface of the semiconductor chip may be protected by a semiconductor processing tape to prevent damage to the semiconductor chip (see Patent Document 1). Furthermore, it is also known that a single-sided adhesive film composed of a metal layer and an adhesive layer is attached to a semiconductor element via an adhesive layer (see Patent Document 2).

  As a typical procedure for flip chip connection, a solder bump or the like formed on the surface of a semiconductor chip to which a semiconductor processing tape is bonded is immersed in a flux, and then an electrode formed on the bump and the substrate (if necessary, this The solder bump is also formed on the electrode), and finally the solder bump is melted to reflow-connect the solder bump and the electrode. Flux is used for the purpose of cleaning solder bumps during soldering, preventing oxidation, improving solder wettability, and the like. With the above procedure, a good electrical connection between the semiconductor chip and the substrate can be established.

  Therefore, an adhesive layer and a protective layer laminated on the adhesive layer can be used as a semiconductor processing tape capable of preventing the occurrence of spots even when flux is attached and capable of producing a semiconductor device having excellent appearance. And a film for flip-chip type semiconductor back surface in which the protective layer is made of a heat-resistant resin or metal having a glass transition temperature of 200 ° C. or higher has been proposed (see Patent Document 3).

JP 2007-158026 A Japanese Patent Laid-Open No. 2007-233502 JP 2012-033626 A

  However, as in Patent Document 1, when a protective film is formed by curing a resin containing a radiation curable component or a thermosetting component with radiation or heat, the thermal expansion coefficient of the cured protective film and the semiconductor wafer Since the difference is large, there is a problem that warpage occurs in a semiconductor wafer or semiconductor chip in the middle of processing.

  In this regard, as in Patent Document 2 and Patent Document 3, warping can be prevented by adhering a metal protective layer (hereinafter referred to as a metal layer) to a semiconductor wafer via an adhesive layer. Here, Patent Document 3 also discloses a flip chip type semiconductor backside film in which a protective layer and an adhesive layer are provided on an adhesive layer of a dicing tape in which an adhesive layer is laminated on a base material. .

  Such a dicing tape-integrated flip chip type semiconductor back film (hereinafter referred to as semiconductor processing tape) is usually provided with a separator on the adhesive layer to protect the adhesive layer. When bonding the adhesive layer to the wafer, the separator layer is peeled off little by little so that the semiconductor wafer is not bonded with the adhesive layer wrinkled. Bonding while pressing with a bonding roller from the dicing tape side. When pasted in this way, the conventional semiconductor processing tape has a problem that wrinkles are generated in the metal layer.

  It is assumed that wrinkles in the protective layer are generated by the following mechanism. When the separator is peeled off, tension is applied to the flip chip type semiconductor back film in one direction. Since the dicing tape has expandability, the dicing tape extends and deforms in the direction in which the tension is applied, and thus wrinkles are generated in the direction in which the tension is applied. If it does so, a wrinkle will arise also in the metal layer and adhesive bond layer which were provided on the dicing tape. However, the flip-chip type semiconductor back film is pressed by the laminating roller immediately after the separator is peeled off. At this time, the dicing tape and the adhesive layer have sufficient flexibility, so that the direction along the laminating roller is The wrinkles generated during the peeling of the separator are eliminated. However, it is considered that the protective layer made of metal cannot follow this and is bonded in a state where wrinkles are generated.

  The semiconductor processing tape as described above is usually a flip chip type semiconductor back film and a dicing tape in which a protective layer and an adhesive layer pre-cut into a predetermined shape corresponding to a semiconductor wafer are formed on a long separator. Are bonded so that the protective layer and the adhesive layer are combined, and the dicing tape is pre-cut into a predetermined shape (usually circular) corresponding to the ring frame from the base film side, and then rolled into a roll shape. ing. When a roll-like semiconductor processing tape is used in this way, the occurrence of wrinkles in the metal layer is particularly remarkable. This will be described in more detail with reference to FIG.

  First, an apparatus and method for bonding the semiconductor processing tape 100 to the semiconductor wafer W and the ring frame R will be schematically described. In FIG. 3, the semiconductor processing tape 100 wound in a roll shape is drawn in a sheet shape in the A direction, and is wound around the B direction by the winding roller 102. A peeling wedge 103 is provided in the lead-out path of the semiconductor processing tape 100, and only the separator 101 is peeled off with the tip of the peeling wedge 103 as a turning point, and is taken up by the take-up roller 102. A bonding table 104 is provided below the tip of the peeling wedge 103, and the semiconductor wafer W and the ring frame R are disposed on the upper surface of the bonding table 104. The flip chip type semiconductor back film 105 (laminated body of metal layer and adhesive layer) and the dicing tape 106 peeled off from the separator 101 by the peeling wedge 103 are guided onto the ring frame R and the semiconductor wafer W and pasted. It is bonded to the ring frame R and the semiconductor wafer W by the combining roller 107. The bonding table 104 has moved leftward in FIG. 3, and the laminate of the flip chip type semiconductor back film 105 and the dicing tape 106 is bonded to the next ring frame R and semiconductor wafer W. Repeated.

  Next, the mechanism by which wrinkles occur in the metal layer during bonding will be described. By adjusting the speed and tension of the roll-shaped semiconductor processing tape 100, the take-up roller 102, and the bonding table 104, the separator 101 before the flip-chip type semiconductor back surface film 105 and the dicing tape 106 are peeled off is in the C direction. The pulling force is applied. This is because the semiconductor processing tape 100 can be bonded without wrinkles by applying tension to the semiconductor processing tape 100 in a tensioned state.

  In the earliest stage of bonding, only the tip of the dicing tape 106 is bonded to the ring frame. Since the dicing tape 106 is usually pre-cut into a circle, the portion to be bonded at this time is in a dot state. And since the remaining part is not peeled off from the separator 101 and remains on the separator 101, it is pulled in the C direction together with the separator 101. Since the dicing tape 106 has expandability, it is stretched and deformed when tension is applied. In addition, since one side is pulled while being fixed at a point, there is a difference in the stretch state between the central portion (near the fixed portion) and the end portion in the short direction of the separator 101, and in the C direction. Wrinkles will occur. When the dicing tape 106 is twisted, the flip chip type semiconductor back surface film 105 provided thereon is also twisted.

  Thereafter, when the bonding table 104 moves and the bonding proceeds, the dicing tape 106 and the flip chip type semiconductor back surface film 105 are sequentially peeled from the separator 101 and released from the tension applied in the C direction. When the dicing tape 106 in the generated state is along the bonding roller 107, the twist is eliminated and the dicing tape 106 is bonded. This is because the dicing tape 106 still has sufficient flexibility even when a tension that causes twisting is applied, and the dicing tape 106 has a force in the direction of pulling along the laminating roller 107, that is, in the short direction of the separator 101. This seems to be because it has the potential to extend in the short direction and eliminate the twist. Similarly, the adhesive layer of the flip-chip type semiconductor back surface film 105 is also bonded to the semiconductor wafer W in a state where the twist is eliminated.

  However, when the metal layer is pulled in the C direction and twisted, the metal layer cannot follow and extend even if pulled in the short direction. As a result, when trying to follow the laminating roller 107, a twist is established as a crease, and a phenomenon occurs in which it is bonded to the semiconductor wafer W in that state.

  If it is bonded to a semiconductor wafer with wrinkles in the metal layer, it will be bonded to the wafer in a state where the thickness uniformity of the flip chip type semiconductor backside film is lost. There is a risk of cracking, and peeling from the adhesive layer is likely to occur from the wrinkled portion, which causes package cracks, resulting in poor reliability.

  Then, this invention makes it a subject to provide the tape for semiconductor processing which can prevent that a metal layer produces a wrinkle at the time of bonding to a semiconductor wafer.

  In order to solve the above problems, a semiconductor processing tape according to the present invention includes a dicing tape having a base film and an adhesive layer, a metal layer provided on the adhesive layer, and the metal layer. An adhesive layer for adhering the metal layer to the back surface of the semiconductor chip, and the loop stiffness of the dicing tape 13 is 20 mN or more and less than 200 mN.

  In the semiconductor processing tape, the metal layer is preferably made of any one of copper, nickel, aluminum, and stainless steel.

  The semiconductor processing tape preferably has a thickness of the dicing tape of 55 μm or more and less than 215 μm.

  According to the present invention, it is possible to prevent wrinkles from being generated in the metal layer during bonding to a semiconductor wafer.

It is sectional drawing which shows typically the structure of the tape for semiconductor processing which concerns on embodiment of this invention. It is sectional drawing for demonstrating the usage method of the tape for semiconductor processing which concerns on embodiment of this invention. It is drawing for demonstrating the apparatus and method of bonding the tape for semiconductor processing to a semiconductor wafer and a ring frame.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 is a cross-sectional view showing a semiconductor processing tape 10 according to an embodiment of the present invention. This semiconductor processing tape 10 has a dicing tape 13 composed of a base film 11 and an adhesive layer 12 provided on the base film 11. On the adhesive layer 12, a semiconductor chip C ( The metal layer 14 for protecting (refer FIG. 2) and the adhesive bond layer 15 provided on the metal layer 14 are provided.

  The adhesive layer 15 is preferably protected by a separator (release liner) on the surface opposite to the surface in contact with the metal layer 14 (not shown). The separator has a function as a protective material that protects the adhesive layer 15 until it is put to practical use. Moreover, a separator can be used as a support base material at the time of bonding the metal layer 14 to the adhesive layer 12 of the dicing tape 13 in the manufacturing process of the semiconductor processing tape 10.

  The dicing tape 13, the metal layer 14, and the adhesive layer 15 may be cut (precut) into a predetermined shape in advance according to the use process and the apparatus. Further, the semiconductor processing tape 10 of the present invention may be in a form cut for every one semiconductor wafer W, or a long sheet in which a plurality of pieces cut for every one semiconductor wafer W are formed. May be wound into a roll. Each component will be described below.

<Base film 11>
As the base film 11, any conventionally known film can be used without particular limitation as long as the loop stiffness of the dicing tape 13 is 20 mN or more and less than 200 mN. When a radiation curable material is used, it is preferable to use a material having radiation transparency.

  For example, as the material, polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-acrylic Α-olefin homopolymer or copolymer such as acid methyl copolymer, ethylene-acrylic acid copolymer, ionomer or a mixture thereof, polyurethane, styrene-ethylene-butene or pentene copolymer, polyamide-polyol Listed are thermoplastic elastomers such as copolymers, and mixtures thereof. The base film 11 may be a mixture of two or more materials selected from these groups, or may be a single layer or a multilayer.

  The thickness of the base film 11 is not particularly limited and may be appropriately set, but is preferably 50 to 200 μm.

  In order to improve the adhesion between the base film 11 and the pressure-sensitive adhesive layer 12, the surface of the base film 11 is subjected to chemical or physical treatment such as chromic acid treatment, ozone exposure, flame exposure, high piezoelectric impact exposure, and ionizing radiation treatment. Surface treatment may be applied.

  Further, in the present embodiment, the pressure-sensitive adhesive layer 12 is provided directly on the base film 11, but a primer layer for improving adhesion, an anchor layer for improving machinability during dicing, stress You may provide indirectly through a relaxation layer, an antistatic layer, etc.

<Adhesive layer 12>
The resin used for the pressure-sensitive adhesive layer 12 is not particularly limited, and a known chlorinated polypropylene resin, acrylic resin, polyester resin, polyurethane resin, epoxy resin, or the like used for the pressure-sensitive adhesive may be used. An acrylic pressure-sensitive adhesive having an acrylic polymer as a base polymer is preferable.

  Examples of the acrylic polymer include (meth) acrylic acid alkyl esters (for example, methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, isopropyl ester). Pentyl 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, (E.g., linear or branched alkyl ester having 1 to 30 carbon atoms, particularly 4 to 18 carbon atoms) of an alkyl group such as octadecyl ester and eicosyl ester) ) Acrylic acid cycloalkyl esters (e.g., cyclopentyl ester, acrylic polymer or the like using one or more of the monomer component 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 contains units corresponding to 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. May be. Examples of such monomer components include, for example, 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; Styrene Contains sulfonic acid groups such as phonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, (meth) acrylamidepropanesulfonic acid, sulfopropyl (meth) acrylate, (meth) acryloyloxynaphthalenesulfonic acid Monomers; Phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl 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) An acrylate etc. are mentioned. 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.

  The acrylic polymer can be prepared, for example, by applying an appropriate method such as a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, or a suspension polymerization method to a mixture of one or more component monomers. The pressure-sensitive adhesive layer 12 preferably has a composition that suppresses the inclusion of a low-molecular-weight substance from the viewpoint of preventing contamination of the wafer. From this point, the main component is an acrylic polymer having a weight average molecular weight of 300,000 or more, particularly 400,000 to 3,000,000. Therefore, the pressure-sensitive adhesive can be of an appropriate crosslinking type by an internal crosslinking method, an external crosslinking method, or the like.

  For controlling the crosslinking density of the pressure-sensitive adhesive layer 12, for example, a polyfunctional isocyanate compound, a polyfunctional epoxy compound, a melamine compound, a metal salt compound, a metal chelate compound, an amino resin compound, or a peroxide. Appropriate methods such as a method of crosslinking using an appropriate external crosslinking agent such as a method, and a method of mixing a low molecular compound having two or more carbon-carbon double bonds and crosslinking by irradiation with energy rays, etc. Can be adopted. 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 parts by weight to 5 parts by weight with respect to 100 parts by weight of the base polymer. In addition, you may use additives, such as various tackifiers and an anti-aging agent, for an adhesive as needed.

  As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 12, a radiation curable pressure-sensitive adhesive is suitable. Examples of the radiation-curable pressure-sensitive adhesive include additive-type radiation-curable pressure-sensitive adhesives in which a radiation-curable monomer component or a radiation-curable oligomer component is blended with the above-mentioned pressure-sensitive adhesive.

  Examples of the radiation curable monomer component to be blended include urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra ( Examples thereof include (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 1,4-butanediol di (meth) acrylate. These monomer components can be used alone or in combination of two or more.

  Examples of the radiation curable oligomer component include various oligomers such as urethane, polyether, polyester, polycarbonate, and polybutadiene, and those having a molecular weight in the range of about 100 to 30,000 are suitable. The compounding amount of the radiation-curable monomer component or oligomer component can be appropriately determined in accordance with the type of the pressure-sensitive adhesive layer, and the amount capable of reducing the adhesive strength of the pressure-sensitive adhesive layer. Generally, it is, for example, about 5 to 500 parts by weight, preferably about 70 to 150 parts by weight with respect to 100 parts by weight of a base polymer such as an acrylic polymer constituting the pressure-sensitive adhesive.

  As the radiation curable pressure-sensitive adhesive, in addition to the additive-type radiation curable pressure-sensitive adhesive, a base polymer having a carbon-carbon double bond in the polymer side chain or main chain or at the main chain terminal was used. An internal radiation-curable pressure-sensitive adhesive is also included. Intrinsic radiation curable adhesives do not need to contain oligomer components, which are low molecular components, or do not contain much, so they are stable without the oligomer components 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. As such a base polymer, those having an acrylic polymer as a basic skeleton are preferable. Examples of the basic skeleton of the acrylic polymer include the acrylic polymers exemplified above.

  The method for introducing the carbon-carbon double bond into the acrylic polymer is not particularly limited, and various methods can be adopted. However, it is easy in terms of molecular design to introduce the carbon-carbon double bond into the polymer side chain. is there. For example, after a monomer having a functional group is previously copolymerized 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. A method of performing 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, and the like. 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. Moreover, 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 preferable 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. Further, 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.

  The internal radiation curable pressure-sensitive adhesive can use the base polymer (particularly acrylic polymer) having the carbon-carbon double bond alone, but the radiation curable monomer component does not deteriorate the characteristics. And photopolymerizable compounds such as oligomer components can also be blended. The compounding amount of the photopolymerizable compound is usually in the range of 30 parts by weight or less, 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.

Among the acrylic polymers described above, in particular, an acrylate ester represented by CH ₂ ═CHCOOR (wherein R is an alkyl group having 4 to 8 carbon atoms), a hydroxyl group-containing monomer, An acrylic polymer A composed of an isocyanate compound having a radical reactive carbon-carbon double bond is preferred.

  When the number of carbon atoms of the alkyl group of the acrylic acid alkyl ester is less than 4, the peel strength may be excessively increased and the pickup property may be deteriorated. On the other hand, when the number of carbon atoms of the alkyl group of the acrylic acid alkyl ester exceeds 8, the adhesion or adhesion to the metal layer 15 is lowered, and as a result, the metal layer 15 may be peeled off during dicing. .

  The acrylic polymer A may contain units corresponding to other monomer components as necessary.

  In the acrylic polymer A, an isocyanate compound having a radical reactive carbon-carbon double bond is used. That is, it is preferable that the acrylic polymer has a configuration in which a double bond-containing isocyanate compound is subjected to an addition reaction with a polymer based on a monomer composition such as an acrylic ester or a hydroxyl group-containing monomer. Therefore, the acrylic polymer preferably has a radical reactive carbon-carbon double bond in its molecular structure. Thereby, it can be set as the active energy ray hardening-type adhesive layer (ultraviolet ray hardening-type adhesive layer etc.) hardened | cured by irradiation of an active energy ray (ultraviolet rays etc.), and the peeling force of the metal layer 15 and the adhesive layer 12 Can be reduced.

  Examples of the double bond-containing isocyanate compound include methacryloyl isocyanate, acryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, 2-acryloyloxyethyl isocyanate, m-isopropenyl-α, α-dimethylbenzyl isocyanate, and the like. A double bond containing isocyanate compound can be used individually or in combination of 2 or more types.

  Moreover, in order to adjust the adhesive force before active energy ray irradiation and the adhesive force after active energy ray irradiation to an active energy ray hardening-type adhesive, an external crosslinking agent can also be used suitably. Specific examples of the external crosslinking method include a method of adding a so-called crosslinking agent such as a polyisocyanate compound, an epoxy compound, an aziridine compound, a melamine crosslinking agent, and reacting them. 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. The amount of the external crosslinking agent used is generally 20 parts by weight or less (preferably 0.1 to 10 parts by weight) with respect to 100 parts by weight of the base polymer. Further, the active energy ray-curable pressure-sensitive adhesive may contain various conventionally known additives such as tackifiers, anti-aging agents, and foaming agents in addition to the above components, if necessary.

  The thickness of the pressure-sensitive adhesive layer 12 is not particularly limited and can be appropriately determined, but is generally about 5 to 200 μm. Moreover, the adhesive layer 12 may be comprised by the single layer, or may be comprised by multiple layers.

  The thickness of the dicing tape 13 is preferably 55 μm or more from the viewpoint of handleability, and preferably 70 μm or more from the viewpoint of increasing the strength of the semiconductor processing tape. Moreover, since an expand is required after dicing, it is preferably less than 215 μm, and from the viewpoint of excellent pick-up properties, it is preferably less than 160 μm.

The dicing tape 13 has a loop stiffness measured under the following conditions of 20 mN or more and less than 200 mN, preferably 26 mN or more, more preferably 33 mN or more.
Loop stiffness measurement conditions:
Device: Loop Steph Tester DA (trade name, manufactured by Toyo Seiki Co., Ltd.)
Loop (sample) shape: length 80mm, width 25mm
Indenter push-in speed: 3.3 mm / sec
Measurement data: A test piece of dicing tape cut out to a width of 25 mm was bent into an Ω-shaped loop so that the surface to which the adhesive layer was attached was inside the loop, and both ends in the length direction were The overlapped portion was held with a chuck so that the circumference of the loop was 80 mm. By fixing the test piece so that the loop is annulus, the load is detected by the load cell when the loop is pressed 10 mm from the time when the indenter contacts the loop at a compression speed of 3.3 mm / sec. taking measurement.

  By setting the loop stiffness of the dicing tape 13 to 20 mN or more, only the tip of the dicing tape 13 is fixed to the ring frame at the earliest stage of bonding the semiconductor processing tape 10 to the semiconductor wafer W, and the remaining portion Even if the separator is pulled in the direction C in FIG. 3 together with the separator, the dicing tape 10 can be prevented from being deformed and extended. For this reason, wrinkles can be prevented from occurring in the dicing tape 10 and the metal layer 14 and adhesive layer 15 provided thereon. When the loop stiffness of the dicing tape 13 is 200 mN or more, the semiconductor wafer W bonded to the semiconductor processing tape 10 is diced into chips (dicing), and then the diced semiconductor chip C is picked up. In this case, when the semiconductor chip C is pushed up from the base film 11 side by the push-up pin, sufficient peeling trigger cannot be made between the metal layer 14 and the adhesive layer 12, and the semiconductor chip C is picked up well. I can't.

<Metal layer 14>
The metal constituting the metal layer 14 is not particularly limited. For example, the laser may be at least one metal selected from the group consisting of aluminum, iron, titanium, tin, nickel, and copper and / or an alloy thereof. It is preferable from the point of marking property. Among these, copper, aluminum, or an alloy thereof has high thermal conductivity, and an effect of heat dissipation through the metal layer is obtained. In addition, copper, aluminum, iron, nickel, or an alloy thereof can also suppress the warp of the electronic device package.

  The thickness of the metal layer 14 can be appropriately determined in consideration of the handleability and workability of the semiconductor wafer W or the semiconductor chip C, and is usually in the range of 2 to 200 μm, preferably 3 to 100 μm. More preferably, it is 4-80 micrometers, and it is especially preferable that it is 5-50 micrometers. When the metal layer is 200 μm or more, winding becomes difficult, and when it is 50 μm or more, productivity is lowered due to workability problems. On the other hand, at least 2 μm or more is necessary from the viewpoint of handleability.

<Adhesive layer 15>
The adhesive layer 15 is a film obtained by previously forming an adhesive.

  The adhesive layer 15 is formed of at least a thermosetting resin, and is preferably formed of at least a thermosetting resin and a thermoplastic resin.

  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, Thermoplastic polyimide resin, polyamide resin such as 6-nylon and 6,6-nylon, phenoxy resin, acrylic resin, saturated polyester resin such as PET (polyethylene terephthalate) and PBT (polybutylene terephthalate), polyamideimide resin, or fluorine resin Etc. A thermoplastic resin can be used individually or in combination of 2 or more types. 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 is linear or branched having 30 or less carbon atoms (preferably 4 to 18 carbon atoms, more preferably 6 to 10 carbon atoms, and particularly preferably 8 or 9 carbon atoms). Examples thereof include a polymer containing one or more esters of acrylic acid or methacrylic acid having an alkyl group as components. That is, in the present invention, acrylic resin has a broad meaning including methacrylic resin. Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, t-butyl group, isobutyl group, pentyl group, isopentyl group, hexyl group, heptyl group, and 2-ethylhexyl group. Octyl group, isooctyl group, nonyl group, isononyl group, decyl group, isodecyl group, undecyl group, dodecyl group (lauryl group), tridecyl group, tetradecyl group, stearyl group, octadecyl group and the like.

  In addition, the other monomer for forming the acrylic resin (a monomer other than an alkyl ester of acrylic acid or methacrylic acid having an alkyl group with 30 or less carbon atoms) is not particularly limited. For example, acrylic acid, Carboxyl group-containing monomers such as methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid or crotonic acid, acid anhydride monomers such as maleic anhydride or itaconic anhydride, (meth) 2-hydroxyethyl acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, (meth) 10-hydroxydecyl acrylate Hydroxyl group-containing monomers such as (meth) acrylic acid 12-hydroxylauryl or (4-hydroxymethylcyclohexyl) -methyl acrylate, styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid Sulfonic acid group-containing monomers such as (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate or (meth) acryloyloxynaphthalene sulfonic acid, or phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate Is mentioned. In addition, (meth) acrylic acid means acrylic acid and / or methacrylic acid, and (meth) of the present invention has the same meaning.

  Examples of the thermosetting resin include an epoxy resin, a phenol resin, an amino resin, an unsaturated polyester resin, a polyurethane resin, a silicone resin, and a thermosetting polyimide resin. A thermosetting resin can be used individually or in combination of 2 or more types. As the thermosetting resin, an epoxy resin containing a small amount of ionic impurities that corrode semiconductor elements is particularly suitable. Moreover, a phenol resin can be used suitably as a hardening | curing agent of an epoxy resin.

  The epoxy resin is not particularly limited. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, brominated bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, bisphenol AF type epoxy. Bifunctional epoxy such as resin, biphenyl type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, phenol novolac type epoxy resin, orthocresol novolak type epoxy resin, trishydroxyphenylmethane type epoxy resin, tetraphenylolethane type epoxy resin Epoxy resin such as resin, polyfunctional epoxy resin, hydantoin type epoxy resin, trisglycidyl isocyanurate type epoxy resin or glycidylamine type epoxy resin It can be used.

  As examples of the epoxy resin, novolak type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type epoxy resins, and tetraphenylolethane type epoxy resins are particularly preferable. 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.

  Furthermore, the phenol resin acts as a curing agent for the epoxy resin. For example, a novolak type phenol resin such as a phenol novolak resin, a phenol aralkyl resin, a cresol novolak resin, a tert-butylphenol novolak resin, a nonylphenol novolak resin, or a resol type. Examples thereof include phenol resins and polyoxystyrene such as polyparaoxystyrene. A phenol resin can be used individually or in combination of 2 or more types. 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 equivalent to 2.0 equivalents per equivalent of epoxy group in the epoxy resin component. More preferred is 0.8 equivalent to 1.2 equivalent. 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.

  Moreover, the thermosetting acceleration | stimulation catalyst of an epoxy resin and a phenol resin may be used. The thermosetting acceleration catalyst 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.

  As the epoxy resin curing agent, a phenol resin is preferably used as described above, but known curing agents such as amines and acid anhydrides can also be used.

  It is important that the adhesive layer 15 has adhesiveness (adhesion) with respect to the back surface (circuit non-formed surface) of the semiconductor wafer. Therefore, in order to crosslink the adhesive layer 15 to some extent in advance, a polyfunctional compound that reacts with a functional group at the end of the molecular chain of the polymer may be added as a crosslinking agent. Thereby, the adhesive property under high temperature can be improved and heat resistance can be improved.

  The crosslinking agent is not particularly limited, and a known crosslinking agent can be used. Specifically, for example, an isocyanate crosslinking agent, an epoxy crosslinking agent, a melamine crosslinking agent, a peroxide crosslinking agent, a urea crosslinking agent, a metal alkoxide crosslinking agent, a metal chelate crosslinking agent, a metal salt Examples thereof include a system crosslinking agent, a carbodiimide crosslinking agent, an oxazoline crosslinking agent, an aziridine crosslinking agent, and an amine crosslinking agent. As the crosslinking agent, an isocyanate crosslinking agent or an epoxy crosslinking agent is suitable. Moreover, the said crosslinking agent can be used individually or in combination of 2 or more types.

  In the present invention, instead of using a cross-linking agent or using a cross-linking agent, it is possible to carry out a cross-linking treatment by irradiation with an electron beam or ultraviolet rays.

  The adhesive layer 15 can be appropriately mixed with other additives as necessary. Examples of other additives include fillers (fillers), flame retardants, silane coupling agents, ion trapping agents, bulking agents, antioxidants, antioxidants, and surfactants.

  The filler may be either an inorganic filler or an organic filler, but an inorganic filler is suitable. By blending a filler such as an inorganic filler, the adhesive layer 15 can be improved in thermal conductivity, adjusted in 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, tin And various inorganic powders made of metals such as zinc, palladium and solder, alloys, and other carbon. A filler can be used individually or in combination of 2 or more types. Among these, silica or alumina is particularly suitable as the filler, and fused silica is particularly suitable as the silica. In addition, it is preferable that the average particle diameter of an inorganic filler exists in the range of 0.01 micrometer-80 micrometers. Moreover, when the thickness of an adhesive bond layer is 20 micrometers or less, it is preferable to exist in the range of 0.01 micrometer-5 micrometers. By setting the average particle size of the inorganic filler within a predetermined range, the adhesiveness can be exhibited without impairing the adhesiveness between the adhesive layer and the adherend such as a metal layer or a wafer. The average particle diameter of the inorganic filler can be measured by, for example, a laser diffraction type particle size distribution measuring apparatus.

  The blending amount of the filler (particularly inorganic filler) is preferably 80% by weight or less (0% by weight to 80% by weight), particularly 0% by weight to 70% by weight with respect to the organic resin component. Is preferred.

  Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resin. A flame retardant can be used individually or in combination of 2 or more types. Examples of the silane coupling agent include β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and the like. A silane coupling agent can be used individually or in combination of 2 or more types. Examples of the ion trapping agent include hydrotalcites and bismuth hydroxide. An ion trap agent can be used individually or in combination of 2 or more types.

  From the viewpoint of adhesiveness and reliability, the adhesive layer 15 contains (A) an epoxy resin, (B) a curing agent, (C) a phenoxy resin, and (D) a surface-treated inorganic filler, The content of D) is preferably 40% by weight or more and 65% by weight or less with respect to the total of (A) to (D).

  (A) By using an epoxy resin, high adhesiveness, water resistance, and heat resistance can be obtained. As the epoxy resin, the above-described known epoxy resins can be used. (B) The above-mentioned well-known hardening | curing agent can be used for a hardening | curing agent.

  (C) The phenoxy resin has a long molecular chain and has a structure similar to that of an epoxy resin, and acts as a flexible material in a composition having a high cross-linking density and imparts high toughness. Composition is obtained. Preferable phenoxy resins are those having a main skeleton of bisphenol A type, but other preferable examples include commercially available phenoxy resins such as bisphenol F type phenoxy resin, bisphenol A / F mixed type phenoxy resin and brominated phenoxy resin.

  (D) As the surface-treated inorganic filler, an inorganic filler surface-treated with a silane coupling agent can be mentioned. As the inorganic filler, the above-described known inorganic fillers can be used, and silica and alumina are preferable. By being surface-treated with the silane coupling agent, the dispersibility of the inorganic filler is improved. For this reason, since it is excellent in fluidity | liquidity, the adhesive force with a metal layer can be improved. Further, since the inorganic filler can be highly filled, the water absorption rate can be lowered and the moisture resistance can be improved.

  The surface treatment of the inorganic filler with the silane coupling agent is carried out by dispersing the inorganic filler in the silane coupling agent solution by a known method, so that the hydroxyl group present on the surface of the inorganic filler and the alkoxy of the silane coupling agent This is performed by reacting a hydrolyzable group such as a group with a hydrolyzed silanol group to form a Si—O—Si bond on the surface of the inorganic filler.

  (D) The content of the surface-treated inorganic filler is 40 weights with respect to the total of (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler. It is preferable that the water absorption rate and the saturated moisture absorption rate can be reduced, and that the heat conductivity of the adhesive layer is improved and the effect of heat dissipation is obtained through the metal layer. (D) The content of the surface-treated inorganic filler is 65 weights with respect to the total of (A) epoxy resin, (B) curing agent, (C) phenoxy resin, and (D) surface-treated inorganic filler. % Or less is preferable because the fluidity of the resin component can be secured, and the adhesive strength to the metal layer or wafer is excellent.

  The thickness of the adhesive layer 15 is not particularly limited, but usually 3 to 100 μm is preferable, and 5 to 20 μm is more preferable. The adhesive layer 15 may be composed of a single layer or a plurality of layers.

The water absorption rate of the adhesive layer 15 is preferably 1.5 vol% or less. The method for measuring the water absorption rate is as follows. That is, 50 × 50 mm adhesive layer 15 (film adhesive) was used as a sample, the sample was dried in a vacuum dryer at 120 ° C. for 3 hours, allowed to cool in a desiccator, and then the dry mass was measured. And M1. The sample is immersed in distilled water at room temperature for 24 hours and then taken out. The surface of the sample is wiped off with a filter paper and quickly weighed to obtain M2. The water absorption rate is calculated by the following equation (1).
Water absorption (vol%) = [(M2-M1) / (M1 / d)] × 100 (1)
Here, d is the density of the film.
If the water absorption exceeds 1.5 vol%, package cracks may occur during solder reflow due to the absorbed water.

ここで、ｄはフィルムの密度である。
飽和吸湿率が１．０ｖｏｌ％を超えると、リフロー時の吸湿により蒸気圧の値が高くなり、良好なリフロー特性が得られないおそれがある。The saturated moisture absorption rate of the adhesive layer 15 is preferably 1.0 vol% or less. The method for measuring the saturated moisture absorption rate is as follows. That is, a circular adhesive layer 15 (film adhesive) having a diameter of 100 mm was used as a sample, the sample was dried at 120 ° C. for 3 hours in a vacuum dryer, allowed to cool in a desiccator, and then the dry mass was measured. To do. The sample is absorbed in a constant temperature and humidity chamber at 85 ° C. and 85% RH for 168 hours, then taken out, and weighed quickly to obtain M2. The saturated moisture absorption rate is calculated by the following equation (2).

Here, d is the density of the film.
When the saturated moisture absorption rate exceeds 1.0 vol%, the value of vapor pressure increases due to moisture absorption during reflow, and good reflow characteristics may not be obtained.

The residual volatile content of the adhesive layer 15 is preferably 3.0 wt% or less. The method for measuring the remaining volatile components is as follows. That is, the adhesive layer 15 (film adhesive) having a size of 50 × 50 mm is used as a sample, the initial mass of the sample is measured as M1, and the sample is heated at 200 ° C. for 2 hours in a hot air circulating thermostat, Weigh to M2. The remaining volatile content is calculated by the following equation (3).
Residual volatile matter (wt%) = [(M2-M1) / M1] × 100 (3)
If the residual volatile content exceeds 3.0 wt%, the solvent is volatilized by heating during packaging, and voids are generated inside the adhesive layer 15, which may cause package cracks.

  The ratio of the linear expansion coefficient of the metal layer 14 to the linear expansion coefficient of the adhesive layer 15 (the linear expansion coefficient of the metal layer 14 / the linear expansion coefficient of the adhesive layer 15) is preferably 0.3 or more. If the ratio is less than 0.3, peeling between the metal layer 14 and the adhesive layer 15 is likely to occur, and package cracks may occur during packaging, which may reduce reliability.

(Separator)
The separator is for improving the handleability of the adhesive layer 15 and protecting the adhesive layer 15. As a separator, polyester (PET, PBT, PEN, PBN, PTT) series, polyolefin (PP, PE) series, copolymer (EVA, EEA, EBA) series, and these materials are partially substituted, A film with improved adhesion and mechanical strength can be used. Moreover, the laminated body of these films may be sufficient.

  The thickness of the separator is not particularly limited and may be appropriately set, but is preferably 25 to 100 μm.

  In the present embodiment, the metal layer 14 is provided directly on the pressure-sensitive adhesive layer 12. However, in the present invention, a peeling layer for improving pick-up property, the semiconductor chip C, the metal layer 14, adhesion When the metal layer 14 is indirectly provided on the pressure-sensitive adhesive layer 12 via a functional layer (for example, a heat dissipation layer) for separating the pressure-sensitive adhesive layer 15 from the pressure-sensitive adhesive layer 12 and imparting a function to the semiconductor chip C. including. Moreover, the case where the adhesive bond layer 15 is indirectly provided on the metal layer 14 via the functional layer is included.

(Method for manufacturing semiconductor processing tape 10)
A method for manufacturing the semiconductor processing tape 10 according to the present embodiment will be described. First, the adhesive layer 15 can be formed using a conventional method of preparing a resin composition and forming it into a film-like layer. Specifically, for example, the resin composition is applied on a suitable separator (such as release paper) and dried (in the case where heat curing is necessary, heat treatment is performed as necessary to dry), Examples include a method of forming the adhesive layer 15. The resin composition may be a solution or a dispersion. Next, the obtained adhesive layer 15 and a separately prepared metal layer 14 are bonded together. As the metal layer 14, a commercially available metal foil may be used. Thereafter, the adhesive layer 15 and the metal layer 14 are pre-cut into a circular label shape of a predetermined size using a pressing blade, and unnecessary peripheral portions are removed.

  Next, the dicing tape 13 is produced. The base film 11 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, the pressure-sensitive adhesive composition is applied on the base film 11 and dried (heat-crosslinked as necessary) to form the pressure-sensitive adhesive layer 12. Examples of the coating method include roll coating, screen coating, and gravure coating. In addition, you may apply | coat an adhesive composition directly to the base film 11, and may form the adhesive layer 12 on the base film 11, and the release paper which performed the peeling process on the surface of the adhesive composition The pressure-sensitive adhesive layer 12 may be transferred to the base film 11 after the pressure-sensitive adhesive layer 12 is formed. Thereby, the dicing tape 13 in which the adhesive layer 12 is formed on the base film 11 is produced.

  Thereafter, the dicing tape 13 is laminated on a separator provided with the circular metal layer 14 and the adhesive layer 15 so that the metal layer 14 and the pressure-sensitive adhesive layer 12 are in contact with each other. In some cases, the dicing tape 13 has a predetermined size. The semiconductor processing tape 10 is made by pre-cutting into a circular label shape or the like.

<How to use>
Next, a method for manufacturing a semiconductor device using the semiconductor processing tape 10 of this embodiment will be described with reference to FIG.

  The manufacturing method of a semiconductor device includes a step of attaching a semiconductor wafer W onto a semiconductor processing tape 10 integrated with a dicing tape (mounting step), and a step of dicing the semiconductor wafer W to form a semiconductor chip C (dicing step). ), A step of separating the semiconductor chip C from the adhesive layer 12 of the dicing tape 13 together with the semiconductor processing tape 10 (pickup step), and a step of flip-chip connecting the semiconductor chip C onto the adherend 16 (flip chip). Connecting step).

[Mounting process]
First, the separator arbitrarily provided on the dicing tape-integrated semiconductor processing tape 10 is appropriately peeled off, and the semiconductor wafer W is adhered to the adhesive layer 15 as shown in FIG. This is adhered and held and fixed (mounting process). At this time, the adhesive layer 15 is in an uncured state (including a semi-cured state). The dicing tape-integrated semiconductor processing tape 10 is attached to the back surface of the semiconductor wafer W. The back surface of the semiconductor wafer W means a surface opposite to the circuit surface (also referred to as a non-circuit surface or a non-electrode forming surface). Although the sticking method is not specifically limited, the method by thermocompression bonding is preferable. The crimping is usually performed while pressing with a pressing means such as a crimping roll. Moreover, heating is performed by using a heat stage as a bonding stand or using a thermocompression bonding roll.

[Dicing process]
Next, as shown in FIG. 2B, the semiconductor wafer W is diced. As a result, the semiconductor wafer W is cut into a predetermined size and divided into pieces (small pieces), whereby the semiconductor chip C is manufactured. For example, the dicing is performed from the circuit surface side of the semiconductor wafer W according to a conventional method. Further, in this step, for example, a cutting method called full cut in which cutting is performed up to the semiconductor processing tape 10 can be employed. 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 W is bonded and fixed with excellent adhesion by the semiconductor processing tape 10, chip chipping and chip jump can be suppressed, and damage to the semiconductor wafer W can be suppressed. In addition, when expanding the dicing tape-integrated semiconductor processing tape 10, the expansion can be performed using a conventionally known expanding apparatus.

[Pickup process]
As shown in FIG. 2C, the semiconductor chip C is picked up, and the semiconductor chip C is peeled off from the dicing tape 13 together with the adhesive layer 15 and the metal layer 14. The pickup method is not particularly limited, and various conventionally known methods can be employed. For example, a method of pushing up each semiconductor chip C from the base film 11 side of the semiconductor processing tape 10 with a needle and picking up the pushed semiconductor chip C with a pickup device, etc. can be mentioned. Note that the back surface of the picked-up semiconductor chip C is protected by the metal layer 14.

[Flip chip connection process]
As shown in FIG. 2D, the picked-up semiconductor chip C is fixed to an adherend 16 such as a substrate by a flip chip bonding method (flip chip mounting method). Specifically, the semiconductor chip C is always placed on the adherend 16 such that the circuit surface (also referred to as a surface, a circuit pattern formation surface, an electrode formation surface, etc.) of the semiconductor chip C faces the adherend 16. Fix according to law. For example, flux is first attached to the bumps 17 as connection portions formed on the circuit surface side of the semiconductor chip C. Next, the bumps 17 and the conductive material 18 are melted while bringing the bumps 17 of the semiconductor chip C into contact with the bonding conductive material 18 (solder or the like) attached to the connection pads of the adherend 16 and pressing them. The electrical conduction between the semiconductor chip C and the adherend 16 can be ensured, and the semiconductor chip C can be fixed to the adherend 16 (flip chip bonding step). At this time, a gap is formed between the semiconductor chip C and the adherend 16, and the air gap distance is generally about 30 μm to 300 μm. After the semiconductor chip C is flip-chip bonded (flip chip connection) on the adherend 16, the flux remaining on the facing surface or gap between the semiconductor chip C and the adherend 16 is cleaned and removed. A sealing material (sealing resin or the like) is filled and sealed.

  As the adherend 16, various substrates such as a lead frame and a circuit substrate (such as a wiring circuit substrate) can be used. The material of such a 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, and a polyimide substrate. Also, a chip-on-chip structure can be obtained by using another semiconductor chip as the adherend 16 and flip-chip connection of the semiconductor chip C.

<Example>
Next, in order to further clarify the effects of the present invention, examples and comparative examples will be described in detail, but the present invention is not limited to these examples.

(1) Preparation of dicing tape (adjustment of pressure-sensitive adhesive layer composition)
As the acrylic copolymer (A1) having a functional group, a copolymer comprising 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate and methacrylic acid, the ratio of 2-ethylhexyl acrylate being 60 mol%, and the weight average molecular weight being 700,000 Was prepared. Next, 2-isocyanatoethyl methacrylate was added so that the iodine value would be 20, and an acrylic copolymer (a- having a glass transition temperature of −50 ° C., a hydroxyl value of 10 mgKOH / g, and an acid value of 5 mgKOH / g) 1) was prepared.

  5 parts by mass of Coronate L (trade name, manufactured by Tosoh Corporation) as a polyisocyanate is added to 100 parts by mass of the acrylic copolymer (a-1), and Esacure KIP 150 (trade name, Lamberti) is used as a photopolymerization initiator. A mixture obtained by adding 3 parts by mass) was dissolved in ethyl acetate and stirred to prepare an adhesive composition.

The following was produced as a base film.
(Base film 1)
A resin bead of a mixture of polypropylene PP and thermoplastic elastomer HSBR (PP: HSBR = 80: 20) is melted at 200 ° C., and formed into a long film having a thickness of 100 μm using an extruder to form a base film 1. Produced. As polypropylene PP, F-300SP (trade name) manufactured by Idemitsu Petrochemical Co., Ltd. was used, and Dynalon 1320P (trade name) manufactured by JSR Corporation was used as the thermoplastic elastomer HSBR.

(Base film 2)
Resin beads of ethylene-acrylic acid copolymer ionomer were melted at 200 ° C. and formed into a long film having a thickness of 150 μm using an extruder to prepare a base film 2. As the ethylene-acrylic acid copolymer ionomer, HiMilan 1706 (trade name) manufactured by Mitsui DuPont Polychemical Co., Ltd. was used.

(Base film 3)
Resin beads of an ethylene-acrylic acid copolymer ionomer were melted at 200 ° C. and formed into a long film having a thickness of 100 μm using an extruder to prepare a base film 3. As the ionomer for the ethylene-acrylic acid copolymer, HiMilan 1601 (trade name) manufactured by Mitsui DuPont Polychemical Co., Ltd. was used.

(Base film 4)
Resin beads of ethylene-acrylic acid copolymer ionomer were melted at 200 ° C. and formed into a long film having a thickness of 100 μm using an extruder to prepare a base film 4. As the ionomer for the ethylene-acrylic acid copolymer, Himiran 1855 (trade name) manufactured by Mitsui DuPont Polychemical Co., Ltd. was used.

(Base film 5)
Resin beads of ethylene-methacrylic acid copolymer were melted at 200 ° C., and formed into a long film having a thickness of 100 μm using an extruder to prepare a base film 5. As the ethylene-methacrylic acid copolymer, Nucleol NO35C (trade name) manufactured by Mitsui DuPont Polychemical Co., Ltd. was used.

(Base film 6)
Polyethylene terephthalate resin beads were melted at 280 ° C., and formed into a long film having a thickness of 100 μm using an extruder to prepare a base film 6. As the polyethylene terephthalate, Cosmo Shine A4100 (trade name) manufactured by Toyobo Co., Ltd. was used.

<Dicing tape (1)>
The pressure-sensitive adhesive composition is applied to a release liner made of a polyethylene-terephthalate film subjected to a release treatment so that the thickness after drying is 10 μm, dried at 110 ° C. for 3 minutes, and then the base film. 1 and the dicing tape (1) was produced.

<Dicing tape (2)>
A dicing tape (2) was produced in the same manner as the dicing tape (1) except that the base film 2 was used.

<Dicing tape (3)>
A dicing tape (3) was produced in the same manner as the dicing tape (1) except that the base film 3 was used.

<Dicing tape (4)>
A dicing tape (4) was produced in the same manner as the dicing tape (1) except that the base film 4 was used.

<Dicing tape (5)>
A dicing tape (5) was produced in the same manner as the dicing tape (1) except that the base film 5 was used.

<Dicing tape (6)>
A dicing tape (6) was produced in the same manner as the dicing tape (1) except that the base film 6 was used.

(2) Preparation of adhesive layer <Adhesive layer (1)>
40 parts by mass of “1002” (trade name, manufactured by Mitsubishi Chemical Corporation, solid bisphenol A type epoxy resin, epoxy equivalent 600) as an epoxy resin, and “806” (trade name, manufactured by Mitsubishi Chemical Corporation, bisphenol F type, manufactured by Mitsubishi Chemical Corporation) 100 parts by mass of epoxy resin, epoxy equivalent 160, specific gravity 1.20), 5 parts by mass of “Dyhard100SF” (trade name, Degussa, Dicyandiamide) as a curing agent, “SO-C2” (trade name, Admafine Stock) as a silica filler 350 parts by mass manufactured by company, average particle size 0.5 μm), and 3 parts by mass of “Aerosil R972” (trade name, manufactured by Nippon Aerosil Co., Ltd., average particle size 0.016 μm primary particle size) as silica filler Methyl ethyl ketone was added to the product and mixed by stirring to obtain a uniform composition.
To this, “PKHH” (trade name, manufactured by INCHEM, mass average molecular weight 52,000, glass transition temperature 92 ° C.) 100 parts by mass as a phenoxy resin, “KBM-802” (trade name, Shin-Etsu Silicone Co., Ltd.) as a coupling agent 0.6 parts by mass of mercaptopropyltrimethoxysilane (manufactured by the company) and “Cureazole 2PHZ-PW” (trade name, manufactured by Shikoku Kasei Co., Ltd., 2-phenyl-4,5-dihydroxymethylimidazole, decomposition) 0.5 parts by mass of (temperature 230 ° C.) was added and mixed with stirring until uniform. Further, this was filtered through a 100-mesh filter and vacuum degassed to obtain a varnish of adhesive composition b-1.

  Adhesive composition b-1 was applied to a separator made of a polyethylene-terephthalate film subjected to a release treatment so that the thickness after drying was 8 μm, dried at 110 ° C. for 5 minutes, and then adhered onto the separator. An adhesive film on which the agent layer (1) was formed was produced.

(3) Metal layer The following were prepared as a metal layer.
<Metal layer (1)>
1085 (trade name, manufactured by Toyo Aluminum Co., Ltd., aluminum foil, thickness 12 μm, thermal conductivity 221 W / m · K)
<Metal layer (2)>
Rolled copper foil (trade name, manufactured by UACJ Corporation, tough pitch copper foil, thickness 18 μm, thermal conductivity 391 W / m · K)
<Metal layer (3)>
C18040 (trade name, manufactured by UACJ Co., Ltd., copper alloy foil, thickness 18 μm, thermal conductivity 322 W / m · K)
<Metal layer (4)>
SUS304 (trade name, manufactured by Nippon Steel & Sumikin Materials Co., Ltd., stainless steel foil, thickness 20 μm, thermal conductivity 16.3 W / m · K)

(4) Production of semiconductor processing tape <Example 1>
A single-sided adhesive film was produced by bonding the adhesive layer (1) and the metal layer (1) obtained as described above under the conditions of a bonding angle of 120 °, a pressure of 0.2 MPa, and a speed of 10 mm / s. The single-sided adhesive film is pre-cut into a shape that can cover the wafer in a shape that allows the dicing tape (1) to be bonded to the ring frame, and the adhesive layer of the dicing tape (1) and the metal layer of the single-sided adhesive film The side was bonded so that the adhesive layer was exposed around the single-sided adhesive film, and the semiconductor processing tape of Example 1 was produced.

<Examples 2-7, Comparative Examples 1-3>
The semiconductor processing tapes of Examples 2 to 7 and Comparative Examples 1 to 3 were manufactured in the same manner as in Example 1 except that the combination of the dicing tape, the adhesive composition, and the metal layer was changed to the combinations shown in Table 1. Produced.

  The following measurements and evaluations were performed on the semiconductor processing tapes according to Examples 1 to 7 and Comparative Examples 1 to 3. The results are shown in Table 1.

(Measurement of loop stiffness)
About the dicing tape used for each Example and the comparative example, the loop stiffness test was measured on condition of the following. The measurement results are shown in Table 1.
Loop stiffness measurement conditions:
Device: Loop Steph Tester DA (trade name, manufactured by Toyo Seiki Co., Ltd.)
Loop (sample) shape: length 80mm, width 25mm
Indenter push-in speed: 3.3 mm / sec
Measurement data: A dicing tape test piece cut out to a width of 25 mm was bent into an Ω-shaped loop so that the surface on which the adhesive layer was attached was inside the loop, and both ends in the length direction were The overlapped portion was held with a chuck so that the circumference of the loop was 80 mm. By fixing the test piece so that the loop is annulus, the load is detected by the load cell when the loop is pressed 10 mm from the time when the indenter contacts the loop at a compression speed of 3.3 mm / sec. taking measurement.

(Evaluation of laminating properties)
The semiconductor processing tape according to each example and comparative example was bonded to 10 semiconductor wafers under the following conditions. Observe the tape for semiconductor processing bonded to the semiconductor wafer, and the one that can be bonded without any wrinkling on the metal layer under both conditions 1 and 2 is a good product. Wrinkles occurred in condition 2, but one that was bonded without any wrinkling on the metal layer in condition 2 was a good product, and one in both conditions 1 and 2 was wrinkled in the metal layer Was evaluated as x as a defective product. The evaluation results are shown in Table 1.

<Lamination condition 1>
Laminating apparatus: Wafer mounter DAM-812M (trade name, manufactured by Takatori Co., Ltd.)
Laminating speed: 30mm / sec
Lamination pressure: 0.1 MPa
Lamination temperature: 90 ° C

<Lamination condition 2>
Laminating apparatus: Wafer mounter DAM-812M (trade name, manufactured by Takatori Co., Ltd.)
Laminating speed: 10mm / sec
Lamination pressure: 0.1 MPa
Lamination temperature: 90 ° C

(Evaluation of pickup properties)
The semiconductor wafer bonded to the semiconductor processing tape according to each example and comparative example is full to a 15 × 8 mm square along the planned division line set by using DAD340 (trade name, manufactured by DISCO Corporation) as a dicing device. Cut. CAP-300II (manufactured by Canon Machinery Co., Ltd.) is used as a die picker device after the adhesive layer is cured by irradiating UV light at 200 mJ / mm ² from the base film side of the dicing tape. Used to pick up. The pin height was set to 400 μm. 100 semiconductor chips were picked up, and those that could be picked up with 95 or more problems were evaluated as good, and those that could pick up less than 95 were evaluated as x as defective. In addition, since the comparative example 1 and the comparative example 3 were not able to be bonded favorable to a semiconductor wafer, the pick-up test was not implemented.

<Evaluation of laser mark properties>
The semiconductor chip obtained by the evaluation of the pick-up property was subjected to character processing under the following conditions. Evaluation was performed according to the following evaluation criteria. When the characters formed by laser marking were visually recognized (visual distance: about 30 cm), ○ was evaluated as a non-defective product, and those that were not visually recognized were evaluated as ×.

<Laser marking conditions>
Laser marking device: MD-X1000 (manufactured by Keyence Corporation, trade name)
Wavelength: 1064nm
Strength: 13W
Scanning speed: 500mm / sec

  As shown in Table 1, since the semiconductor processing tapes according to Examples 1 to 7 have a loop stiffness of the dicing tape of 21 mN or more and 174 mN or less and 20 mN or more and less than 200 mN specified in the claims, laminating properties and pickup properties Both were good results.

  On the other hand, the semiconductor processing tapes according to Comparative Examples 1 and 3 had a poor laminating property because the loop stiffness of the dicing tape was less than 20 mN. Further, the semiconductor processing tape according to Comparative Example 2 had a poor pick-up property because the loop stiffness of the dicing tape was 200 mN or more.

10: Semiconductor processing tape 11: Base film 12: Adhesive layer 13: Dicing tape 14: Metal layer 15: Adhesive layer

Claims (3)

A dicing tape having a base film and an adhesive layer;
A metal layer provided on the adhesive layer;
Provided on the metal layer, and having an adhesive layer for bonding the metal layer to the back surface of the semiconductor chip,
A loop for semiconductor processing, wherein the dicing tape has a loop stiffness of 20 mN or more and less than 200 mN.   2. The semiconductor according to claim 1, wherein the metal layer is made of at least one metal selected from the group consisting of aluminum, iron, titanium, tin, nickel and copper and / or an alloy thereof. Tape for processing.   The semiconductor processing tape according to claim 1, wherein a thickness of the dicing tape is 55 μm or more and less than 215 μm.

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