JP6437431B2 - Manufacturing method of semiconductor chip - Google Patents

Description

  The present invention relates to a method for manufacturing a semiconductor chip, and more particularly to a method for manufacturing a semiconductor chip in which a so-called blade dicing method or a tip dicing method and a mounting process employing flip chip bonding are successively performed.

  In recent years, semiconductor devices have been manufactured using a so-called flip chip bonding or a mounting method called a face down method. In this system, a semiconductor chip (hereinafter, also simply referred to as “chip”) having convex electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to a substrate.

  A semiconductor chip is obtained by dividing a semiconductor wafer into pieces, and a liquid epoxy resin or the like has been used for bonding the chip and the substrate. However, from the viewpoint of process simplification and quality uniformity, a film-like die bonding agent (adhesive film for die bonding (hereinafter sometimes simply referred to as “adhesive film”)) has come to be used. It was. When mounting using such an adhesive film in a face-down manner, it is simple in terms of the process to provide an adhesive film in advance on the circuit surface of the chip.

  As a method for obtaining a chip having an adhesive film on a circuit surface, Patent Document 1 (Japanese Patent Laid-Open No. 2008-98427) discloses a method of laminating an adhesive film for die bonding on a circuit surface of a wafer and completely cutting the adhesive film. In addition, a groove having a depth of cut shallower than the wafer thickness is formed in the laminate of the adhesive film and the wafer from the wafer surface, and then a surface protective sheet is applied to the adhesive film, and the wafer is ground by backside grinding. Is described.

  Patent Document 2 (Japanese Unexamined Patent Application Publication No. 2009-152424) discloses a sheet sticking apparatus mainly used for sticking a protective sheet on a circuit surface of a semiconductor wafer or sticking an adhesive film for die bonding on a back surface. It is disclosed. However, Patent Document 2 does not intend to attach a die bonding adhesive film to the circuit surface of a semiconductor wafer.

JP 2008-98427 A JP 2009-152424 A

  In recent years, the shape and distribution density of convex electrodes (also referred to as bumps) formed on the circuit surface have varied, and it has become difficult to apply an adhesive film following the bumps on the circuit surface. If the bumps are relatively low and the distribution density is low, even if the adhesive film can be applied by following the bumps sufficiently, the bump height will change, and if the distribution density is different, the same adhesive film However, there was a case where it could not be pasted sufficiently following the bump. As a result, even when the obtained semiconductor chip with an adhesive film is die-bonded, the adhesive force between the chip and the chip mounting substrate is insufficient, or there is no void (void) around the bump. There is a concern that reliability may be reduced after mounting, or that bumps may not penetrate the adhesive film during die bonding, resulting in poor connection.

  The present invention has been made in view of the above circumstances. That is, an object of the present invention is to provide a method for manufacturing a semiconductor chip having improved followability of the adhesive film to the bumps when the adhesive film is applied.

  The present invention includes the following gist.

(1) A step of applying an adhesive film for die bonding to a circuit surface of a semiconductor wafer having a circuit formed on the surface under reduced pressure;
A method for manufacturing a semiconductor chip, comprising: separating a semiconductor wafer and an adhesive film for die bonding for each circuit to obtain a chip having an adhesive film for die bonding on a circuit surface.

(2) The die bonding adhesive film of the adhesive sheet comprising the support sheet and the die bonding adhesive film supported on the die sheet is evacuated to the circuit surface of the semiconductor wafer on which the circuit is formed. Paste below,
Then, the manufacturing method of the semiconductor chip as described in (1) including the process of peeling a support sheet from the adhesive film for die bonding.

(3) The method of manufacturing a semiconductor chip according to (2), wherein the support sheet of the adhesive sheet has a step absorption layer, and an adhesive film for die bonding is detachably supported on the step absorption layer.

(4) The method for manufacturing a semiconductor chip according to any one of (1) to (3), wherein a convex electrode is provided on a circuit surface of the semiconductor wafer.

(5) The method for manufacturing a semiconductor chip according to any one of (1) to (4), wherein the step of attaching the die-bonding adhesive film is performed under reduced pressure with a pressure environment of 50 to 400 Pa.

  According to the present invention, in a chip manufacturing method in which a so-called blade dicing method or a tip dicing method and a mounting process employing flip chip bonding are continuously performed, the adhesive film is applied to the bumps when the adhesive film is applied. Followability can be improved. For this reason, the manufacturing process of the semiconductor chip with an adhesive film can be stabilized. In addition, product quality can be improved.

An aspect of the adhesive sheet containing the adhesive film 20 for die bonding is shown. An aspect of the adhesive sheet containing the adhesive film 20 for die bonding is shown. An aspect of the adhesive sheet containing the adhesive film 20 for die bonding is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown. The example of the type of the order of each process in an example of the manufacturing method of a semiconductor chip is shown. One process of the manufacturing method of a semiconductor chip is shown.

  Hereinafter, the present invention will be described more specifically with reference to the drawings, including the best mode.

  In the method for manufacturing a semiconductor chip according to the present invention, after bonding a die bonding adhesive film 20 to a circuit surface of a semiconductor wafer 10 having a circuit formed on the surface under reduced pressure, the semiconductor wafer 10 and the die bonding adhesive film are bonded. 20 is obtained by dividing the circuit board 20 into individual circuits and obtaining the chip 11 having the die bonding adhesive film 20 on the circuit surface. The method for dividing the wafer 10 and the adhesive film 20 is not particularly limited as described later, and various methods can be adopted.

  The present invention is characterized in that the adhesive film is attached to the wafer circuit surface under reduced pressure. The method of attaching the die bonding adhesive film 20 to the circuit surface of the wafer 10 is not particularly limited as long as the adhesive film can be attached by reducing the pressure between the wafer circuit surface and the adhesive surface of the adhesive film. As an example of a non-limiting method, a single-leaf adhesive film in which an adhesive film is die-cut into substantially the same shape as the wafer 10 is prepared, and the single-leaf adhesive film and the wafer are stacked in a vacuum chamber, and the pressure in the chamber is reduced. Later, there is a method of pressure bonding or thermocompression bonding of the single-leaf adhesive film and the wafer. Moreover, by using the sheet sticking apparatus described in Patent Document 2, the adhesive film can be supplied in a long state, and the sticking process can be continued and automated under reduced pressure, which is more preferable.

  Here, “under reduced pressure” means that the space between the wafer circuit surface and the adhesive surface of the adhesive film is a pressure environment of atmospheric pressure or less, preferably the pressure environment is 400 Pa or less, more preferably 50. It is sufficient that the pressure is reduced to about 400 Pa, more preferably about 80 to 350 Pa. If the pressure environment is in such a range, it is possible to sufficiently follow the unevenness of the adherend surface of the adhesive film. In addition, the adhesive film usually contains a relatively large amount of low molecular weight components, and depending on the degree of the reduced pressure environment, there is a concern about the generation of outgas. However, if the pressure environment is in such a range, the generation of outgas can be suppressed. The pressure environment may be a dry atmosphere or an inert gas atmosphere such as nitrogen. By attaching the adhesive film to the wafer circuit surface under reduced pressure, air contamination between the circuit surface and the adhesive film can be reduced, and the followability to bumps formed on the circuit surface of the wafer is improved. .

  In addition to the decompression chamber, a pressure chamber for pressing the adhesive film via a diaphragm or the like and sticking to the adherend may be provided in the sticking device. The pressure environment in the pressure chamber is preferably about 0.1 MPa to 0.4 MPa.

  The adhesive film 20 may be affixed to the wafer surface in a pre-cut form that has been pre-cut into substantially the same shape as the semiconductor wafer 10, and after adhering an adhesive film having a planar shape larger than the wafer, along the outer diameter of the wafer. The outer peripheral portion of the adhesive film may be excised.

  The adhesive film 20 may be a single layer film or a multilayer film composed of two or more layers having different compositions. Further, the adhesive film 20 may be supplied to the attaching process with the semiconductor wafer 10 in a state where the adhesive film 20 is detachably supported on the support sheet 21. Below, the laminated body of the adhesive film 20 and a support sheet may be called an "adhesion sheet." The bonding of the adhesive sheet and the semiconductor wafer 10 is performed under reduced pressure as described above, and the support sheet is peeled off at an arbitrary stage thereafter. Further, the support sheet 21 may have a step absorption layer 22 in order to absorb the difference in height of the wafer circuit surface and adhere the adhesive film to the wafer surface. Non-limiting aspects of these adhesive film, support sheet, and step absorption layer will be described.

(Adhesive film 20 for die bonding)
The functions required at least for the die bonding adhesive film 20 are (1) sheet shape maintenance, (2) initial adhesion, and (3) curability.

  The adhesive film 20 can be provided with (1) sheet shape maintainability and (3) curability by addition of a binder component. As the binder component, a polymer component (A) and a curable component (B) are used. The 1st binder component to contain or the 2nd binder component containing the curable polymer component (AB) which has the property of (A) component and (B) component can be used.

  The adhesive film 20 is a function for temporarily attaching to the adherend (semiconductor wafer 20 or semiconductor chip 21) until curing (2) The initial adhesiveness may be pressure-sensitive adhesiveness, It may have a property of being softened and bonded by heat. (2) The initial adhesiveness is usually controlled by adjusting various properties of the binder component and adjusting the blending amount of the inorganic filler (C) described later.

(First binder component)
A 1st binder component provides film forming property and sclerosis | hardenability to an adhesive film by containing a polymer component (A) and a sclerosing | hardenable component (B). In addition, the 1st binder component does not contain a curable polymer component (AB) for the convenience of distinguishing from a 2nd binder component.

(A) Polymer component The polymer component (A) is added to the adhesive film mainly for the purpose of imparting sheet shape maintenance to the adhesive film.

In order to achieve the above object, the polymer component (A) has a weight average molecular weight (Mw) of usually 20,000 or more, preferably 20,000 to 3,000,000. The value of the weight average molecular weight (Mw) is a value when measured by a gel permeation chromatography method (GPC) method (polystyrene standard). Measured by such a method is, for example, in high-speed GPC device manufactured by Tosoh Corporation "HLC-8120GPC", high-speed column "TSK gurd column H _XL -H", "TSK Gel GMH _XL", "TSK Gel G2000 H _XL" (The above, all manufactured by Tosoh Corporation) are connected in this order, and the detector is used as a differential refractometer at a column temperature of 40 ° C. and a liquid feed rate of 1.0 mL / min.

  In addition, for convenience to distinguish from the curable polymer (AB) described later, the polymer component (A) does not have a curing functional functional group described later.

  As the polymer component (A), an acrylic polymer, polyester, phenoxy resin (for the purpose of distinguishing from the curable polymer (AB) described later, limited to those having no epoxy group), polycarbonate, polyether, polyurethane Polysiloxane, rubber polymer, etc. can be used. In addition, an acrylic urethane resin obtained by reacting a urethane prepolymer having an isocyanate group at a molecular terminal with an acrylic polyol having an hydroxyl group and an acrylic polyol having a combination of two or more of these, Also good. Furthermore, two or more of these may be used in combination, including a polymer in which two or more are bonded.

(A1) As the acrylic polymer polymer component (A), acrylic polymer (A1) is preferably used. The glass transition temperature (Tg) of the acrylic polymer (A1) is preferably in the range of −60 to 50 ° C., more preferably −50 to 40 ° C., and further preferably −40 to 30 ° C. If the glass transition temperature of the acrylic polymer (A1) is too low, the peeling force between the adhesive film 20 and the support sheet 21 may increase, and transfer failure of the adhesive film may occur. In some cases, the film may be lowered and cannot be transferred to the adherend, or the adhesive film may be peeled off from the adherend after transfer.

  The weight average molecular weight of the acrylic polymer (A1) is more preferably 100,000 to 1,500,000. If the weight average molecular weight of the acrylic polymer (A1) is too low, the adhesiveness between the adhesive film 20 and the support sheet 21 is increased, and transfer failure of the adhesive film may occur. In some cases, the film may be lowered and cannot be transferred to the adherend, or the adhesive film may be peeled off from the adherend after transfer.

  The acrylic polymer (A1) contains (meth) acrylic acid ester in at least a constituent monomer.

  As the (meth) acrylic acid ester, an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, specifically, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate, etc .; (meth) acrylate having a cyclic skeleton, specifically cycloalkyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl ( Examples include meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and imide (meth) acrylate. Moreover, what is (meth) acrylic acid ester can be illustrated among what is illustrated as a monomer which has a hydroxyl group mentioned later, a monomer which has a carboxyl group, and a monomer which has an amino group.

  In the present specification, (meth) acryl may be used to include both acrylic and methacrylic.

  A monomer having a hydroxyl group may be used as the monomer constituting the acrylic polymer (A1). By using such a monomer, when a hydroxyl group is introduced into the acrylic polymer (A1) and the adhesive film contains an energy ray-curable component (B2) separately, this and the acrylic polymer (A1). ) Is improved. Examples of the monomer having a hydroxyl group include (meth) acrylic acid ester having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; N-methylol (meth) acrylamide and the like.

  As the monomer constituting the acrylic polymer (A1), a monomer having a carboxyl group may be used. By using such a monomer, when a carboxyl group is introduced into the acrylic polymer (A1) and the adhesive film contains an energy ray-curable component (B2) separately, this and the acrylic polymer Compatibility with (A1) is improved. Examples of the monomer having a carboxyl group include (meth) acrylic acid, maleic acid, fumaric acid, and itaconic acid. When using an epoxy-based thermosetting component as the curable component (B) described below, the carboxyl group and the epoxy group in the epoxy-based thermosetting component react with each other. The amount used is preferably small.

  As a monomer constituting the acrylic polymer (A1), a monomer having an amino group may be used. Examples of such a monomer include (meth) acrylic acid esters having an amino group such as monoethylamino (meth) acrylate.

  In addition, vinyl acetate, styrene, ethylene, α-olefin, or the like may be used as a monomer constituting the acrylic polymer (A1).

  The acrylic polymer (A1) may be cross-linked. When the acrylic polymer (A1) is crosslinked, the acrylic polymer (A1) before being crosslinked has a crosslinkable functional group such as a hydroxyl group. Moreover, a crosslinking agent is added to the composition for forming the adhesive film 20. Crosslinking is carried out by the reaction between the crosslinkable functional group and the functional group of the crosslinking agent. By crosslinking the acrylic polymer (A1), it is possible to adjust the initial adhesive force and cohesive force of the adhesive film.

  Examples of the crosslinking agent include organic polyvalent isocyanate compounds and organic polyvalent imine compounds.

  Examples of organic polyvalent isocyanate compounds include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, alicyclic polyvalent isocyanate compounds, trimers of these organic polyvalent isocyanate compounds, and these organic polyvalent isocyanate compounds. Examples thereof include terminal isocyanate urethane prepolymers obtained by reacting with a polyol compound.

  Specifically, as the organic polyvalent isocyanate compound, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane-4,4′- Diisocyanate, diphenylmethane-2,4′-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, dicyclohexylmethane-2,4′-diisocyanate, and lysine isocyanate thereof Examples thereof include polyhydric alcohol adducts.

  Specific examples of organic polyvalent imine compounds include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylol. Mention may be made of methane-tri-β-aziridinylpropionate and N, N′-toluene-2,4-bis (1-aziridinecarboxamide) triethylenemelamine.

  A crosslinking agent is 0.01-20 mass parts normally with respect to 100 mass parts of acrylic polymers (A1) before bridge | crosslinking, Preferably it is 0.1-10 mass parts, More preferably, it is 0.5-5 mass parts. Used in ratio.

  In the present invention, when the content of the component constituting the adhesive film is determined with reference to the content of the polymer component (A), when the polymer component (A) is a crosslinked acrylic polymer, The reference content is the content of the acrylic polymer before being crosslinked.

(A2) Non-acrylic resin In addition, as the polymer component (A), polyester, phenoxy resin (for the purpose of distinguishing from the curable polymer (AB) described later, limited to those having no epoxy group), polycarbonate, poly One type of non-acrylic resin (A2) selected from ethers, polyurethanes, polysiloxanes, rubber polymers, or a combination of two or more of these may be used, or a combination of two or more types. Such a resin preferably has a weight average molecular weight of 20,000 to 100,000, and more preferably 20,000 to 80,000.

  The glass transition temperature of the non-acrylic resin (A2) is preferably -30 to 150 ° C, more preferably -20 to 120 ° C. If the glass transition temperature of the non-acrylic resin is too low, the peeling force between the adhesive film and the support sheet is increased, and transfer failure of the adhesive film may occur. If the glass transition temperature is too high, the adhesive force between the adhesive film and the adherend may be insufficient.

  When the non-acrylic resin (A2) is used in combination with the above-mentioned acrylic polymer (A1), a support sheet is used when the adhesive film is transferred to the adherend using a composite sheet for forming a protective film described later. The delamination between the adhesive film 21 and the adhesive film 20 can be easily performed. Further, the adhesive film tends to easily follow irregularities such as bumps on the transfer surface.

  When the non-acrylic resin (A2) is used in combination with the above-mentioned acrylic polymer (A1), the content of the non-acrylic resin (A2) is such that the non-acrylic resin (A2) and the acrylic polymer ( The mass ratio (A2: A1) to A1) is usually in the range of 1:99 to 60:40, preferably 1:99 to 30:70. When the content of the non-acrylic resin (A2) is in this range, the above effect can be obtained to a higher degree.

(B) Curable component The curable component (B) is added to the adhesive film mainly for the purpose of imparting curability to the adhesive film 20. As the curable component (B), a thermosetting component (B1) or an energy beam curable component (B2) can be used. Moreover, you may use combining these. The thermosetting component (B1) contains at least a compound having a functional group that reacts by heating. The energy ray-curable component (B2) contains a compound (B21) having a functional group that reacts by irradiation with energy rays, and is polymerized and cured when irradiated with energy rays such as ultraviolet rays and electron beams. Curing is realized by the functional groups of these curable components reacting to form a three-dimensional network structure. Since the curable component (B) is used in combination with the polymer component (A), it is usually from the viewpoint of suppressing the increase in viscosity of the coating composition for forming the adhesive film and improving the handleability. The weight average molecular weight (Mw) is 10,000 or less, and preferably 100 to 10,000.

(B1) When the thermosetting component adhesive film is cured, it may be difficult to irradiate the adhesive film sandwiched between the chip mounting portion and the chip with energy rays, so the thermosetting component (B1 ) Is preferably used. As the thermosetting component, for example, an epoxy thermosetting component is preferable.
The epoxy thermosetting component preferably contains a compound (B11) having an epoxy group and a combination of a compound (B11) having an epoxy group and a thermosetting agent (B12).

(B11) Compound having an epoxy group As the compound (B11) having an epoxy group (hereinafter sometimes referred to as “epoxy compound (B11)”), a conventionally known compound can be used. Specifically, polyfunctional epoxy resin, bisphenol A diglycidyl ether and its hydrogenated product, orthocresol novolac epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type Examples thereof include epoxy compounds having two or more functional groups in the molecule, such as epoxy resins and phenylene skeleton type epoxy resins. These can be used individually by 1 type or in combination of 2 or more types.

  When the epoxy compound (B11) is used, the adhesive film preferably contains 1 to 1500 parts by mass of the epoxy compound (B11) with respect to 100 parts by mass of the polymer component (A), more preferably 3 -1200 mass part is contained. If the epoxy compound (B11) is less than 1 part by mass, sufficient adhesiveness may not be obtained. If the epoxy compound (B11) exceeds 1500 parts by mass, the peel strength between the adhesive film 20 and the support sheet 21 increases, and the adhesive film is transferred. Defects may occur. From the viewpoint of further improving the followability of the adhesive film to the bump, the adhesive film preferably contains 100 to 1200 parts by mass of the epoxy compound (B11) with respect to 100 parts by mass of the polymer component (A).

(B12) Thermosetting agent The thermosetting agent (B12) functions as a curing agent for the epoxy compound (B11). A preferable thermosetting agent includes a compound having two or more functional groups capable of reacting with an epoxy group in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, and an acid anhydride. Of these, phenolic hydroxyl groups, amino groups, acid anhydrides and the like are preferable, and phenolic hydroxyl groups and amino groups are more preferable.

  Specific examples of the phenolic curing agent include polyfunctional phenolic resin, biphenol, novolac type phenolic resin, dicyclopentadiene type phenolic resin, zylock type phenolic resin, and aralkylphenolic resin. A specific example of the amine curing agent is DICY (dicyandiamide). These can be used individually by 1 type or in mixture of 2 or more types.

  It is preferable that it is 0.1-500 mass parts with respect to 100 mass parts of epoxy compounds (B11), and, as for content of a thermosetting agent (B12), it is more preferable that it is 1-200 mass parts. If the content of the thermosetting agent is small, the adhesiveness may not be obtained due to insufficient curing, and if it is excessive, the moisture absorption rate of the adhesive film may increase and the reliability of the semiconductor device may be reduced.

(B13) Curing accelerator A curing accelerator (B13) may be used to adjust the rate of thermal curing of the adhesive film. The curing accelerator (B13) is particularly preferably used when an epoxy thermosetting component is used as the thermosetting component (B1).

  Preferred curing accelerators include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl- Imidazoles such as 4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole; Organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine; And tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphinetetraphenylborate. These can be used individually by 1 type or in mixture of 2 or more types.

  The curing accelerator (B13) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the total amount of the epoxy compound (B11) and the thermosetting agent (B12). Included in the amount of. By containing the curing accelerator (B13) in an amount within the above range, it has excellent adhesiveness even when exposed to high temperatures and high humidity, and has high reliability even when exposed to severe reflow conditions. Can be achieved. If the content of the curing accelerator (B13) is small, sufficient adhesion cannot be obtained due to insufficient curing, and if it is excessive, the curing accelerator having a high polarity is placed on the adhesive interface side in the adhesive film under high temperature and high humidity. By moving and segregating, the reliability of the semiconductor device may be reduced.

(B2) The energy ray-curable component adhesive film contains the energy ray-curable component, so that the adhesive film can be cured without performing a heat curing step that requires a large amount of energy and a long time. Thereby, the manufacturing cost can be reduced. Moreover, when using as a film-form adhesive for die bonding, when an adhesive film contains both a thermosetting component (B1) and an energy-beam curable component (B2), an adhesive film is energy before a thermosetting process. It can be pre-cured by radiation. Thereby, the adhesiveness of the interface between the adhesive film 20 and the support sheet 21 is controlled, or the process suitability of the film adhesive in the process performed before the thermosetting process such as a wire bonding process is improved. Is possible.

  As the energy ray-curable component, the compound (B21) having a functional group that reacts by irradiation with energy rays may be used alone, but the compound (B21) having a functional group that reacts by irradiation with energy rays and a photopolymerization initiator ( It is preferable to use a combination of B22).

(B21) Compound having a functional group that reacts upon irradiation with energy rays Compound (B21) having a functional group that reacts upon irradiation with energy rays (hereinafter sometimes referred to as “energy ray-reactive compound (B21)”) Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butylene glycol diacrylate, 1,6-hexanediol diacrylate Examples include acrylate compounds such as acrylates, oligoester acrylates, urethane acrylate oligomers, epoxy acrylates, polyether acrylates, and esters. A acrylate compound having a polymerizable structure acrylate compounds such as Con acid oligomer include those of relatively low molecular weight. Such a compound has at least one polymerizable double bond in the molecule.

  When the energy ray reactive compound (B21) is used, the adhesive film preferably contains 1 to 1500 parts by mass of the energy ray reactive compound (B21) with respect to 100 parts by mass of the polymer component (A). More preferably, it is contained in 3 to 1200 parts by mass.

(B22) By combining the photopolymerization initiator energy beam reactive compound (B21) with the photopolymerization initiator (B22), the polymerization curing time can be shortened and the amount of light irradiation can be reduced.

  Specific examples of such a photopolymerization initiator (B22) include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, benzoin methyl benzoate, and benzoin dimethyl ketal. 2,4-diethylthioxanthone, α-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 1,2-diphenylmethane, 2-hydroxy- 2-methyl-1- [4- (1-methylvinyl) phenyl] propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and β -Chloranthraquinone and the like. A photoinitiator (B22) can be used individually by 1 type or in combination of 2 or more types.

  As a mixture ratio of a photoinitiator (B22), it is preferable that 0.1-10 mass parts is contained with respect to 100 mass parts of energy-beam reactive compounds (B21), and it is more contained 1-5 mass parts. preferable.

  If the blending ratio of the photopolymerization initiator (B22) is less than 0.1 parts by mass, sufficient curability may not be obtained due to insufficient photopolymerization, and if it exceeds 10 parts by mass, the residue does not contribute to photopolymerization. May cause a malfunction.

(Second binder component)
A 2nd binder component provides film forming property (sheet formation property) and curability to an adhesive film by containing a curable polymer component (AB).

(AB) Curable polymer component The curable polymer component is a polymer having a functional functional group. The curing functional group is a functional group that can react with each other to form a three-dimensional network structure, and examples thereof include a functional group that reacts by heating and a functional group that reacts by energy rays.

  The functional functional group may be added to the unit of a continuous structure that becomes the skeleton of the curable polymer (AB) or may be added to the terminal. When the functional functional group is added in the unit of the continuous structure that becomes the skeleton of the curable polymer component (AB), the functional functional group may be added to the side chain or directly to the main chain. You may do it. The weight average molecular weight (Mw) of the curable polymer component (AB) is usually 20,000 or more from the viewpoint of achieving the purpose of imparting sheet shape maintenance to the adhesive film.

  An example of a functional group that reacts by heating is an epoxy group. Examples of the curable polymer component (AB) having an epoxy group include phenoxy resins having an epoxy group, and specific product names include jER1256 and jER4250 manufactured by Mitsubishi Chemical Corporation.

  The curable polymer component is the same polymer as the above-mentioned acrylic polymer (A1), and is polymerized using a monomer having an epoxy group as the monomer (epoxy group-containing acrylic). System polymer). Examples of such monomers include (meth) acrylic acid esters having a glycidyl group such as glycidyl (meth) acrylate.

  When an epoxy group-containing acrylic polymer is used, the preferred embodiment is the same as that of the acrylic polymer (A1).

  When the curable polymer component (AB) having an epoxy group is used, the thermosetting agent (B12) or the curing accelerator (B13) is used as in the case of using an epoxy thermosetting component as the curable component (B). ) May be used in combination.

  Examples of the functional group that reacts with energy rays include a (meth) acryloyl group. As the curable polymer component (AB) having a functional group that reacts with energy rays, an acrylate compound having a polymer structure such as polyether acrylate, and the like having a high molecular weight can be used.

  In addition, for example, a raw material polymer having a functional group X such as a hydroxyl group in a side chain, a functional group Y that can react with the functional group X (for example, an isocyanate group when the functional group X is a hydroxyl group) and energy beam irradiation Alternatively, a polymer prepared by reacting a low molecular compound having a functional group that reacts with the above may be used.

  In this case, when a raw material polymer corresponds to the above-mentioned acrylic polymer (A), the preferable aspect of the raw material polymer is the same as that of the acrylic polymer (A).

  When the curable polymer component (AB) having a functional group that reacts with energy rays is used, the photopolymerization initiator (B22) may be used in the same manner as when the energy ray curable component (B2) is used. .

  The second binder component may contain the above-described polymer component (A) and curable component (B) in combination with the curable polymer component (AB).

  In addition to the binder component, the adhesive film may contain the following components.

(C) The inorganic filler adhesive film may contain an inorganic filler (C). By blending the inorganic filler (C) into the adhesive film, it is possible to adjust the thermal expansion coefficient of the cured adhesive film, and the thermal expansion of the cured adhesive film with respect to the semiconductor chip 11 that is the adherend. The reliability of the semiconductor device can be improved by optimizing the coefficient. It is also possible to reduce the moisture absorption rate of the cured adhesive film.

  Preferred inorganic fillers include powders of silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride, and the like, beads formed by spheroidizing these, single crystal fibers, glass fibers, and the like. Among these, silica filler and alumina filler are preferable. The said inorganic filler (C) can be used individually or in mixture of 2 or more types. As a range of the content of the inorganic filler (C) for obtaining the above-described effect more reliably, the proportion of the total solid content constituting the adhesive film is preferably 1 to 80% by mass, more preferably It is 5-75 mass%, Most preferably, it is 15-60 mass%.

(D) Coupling agent The coupling agent (D) having a functional group that reacts with an inorganic substance and a functional group that reacts with an organic functional group is bonded to the adherend of the adhesive film, adhesion, and / or aggregation of the adhesive film. It may be used to improve the property. Moreover, the water resistance can be improved by using a coupling agent (D), without impairing the heat resistance of the adhesive film obtained by hardening | curing an adhesive film. Examples of such coupling agents include titanate coupling agents, aluminate coupling agents, silane coupling agents, and the like. Of these, silane coupling agents are preferred.

As a silane coupling agent, the functional group that reacts with the organic functional group is a group that reacts with the functional group of the polymer (A), the curable component (B), the curable polymer component (AB), and the like. A silane coupling agent is preferably used.
Examples of such silane coupling agents include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- (methacryloxy). Propyl) trimethoxysilane, γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N -Phenyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltri Methoxysilane , Methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazolesilane. These can be used individually by 1 type or in mixture of 2 or more types.

  The silane coupling agent is usually 0.1 to 20 with respect to a total of 100 parts by mass of the polymer (A) having a weight average molecular weight of 10,000 or more, the curable component (B), and the curable polymer component (AB). It is contained in a proportion of mass parts, preferably 0.2-10 mass parts, more preferably 0.3-5 mass parts. If the content of the silane coupling agent is less than 0.1 parts by mass, the above effect may not be obtained, and if it exceeds 20 parts by mass, it may cause outgassing.

(E) In addition to the above, various additives may be added to the general-purpose additive adhesive film as necessary. Examples of various additives include leveling agents, plasticizers, antistatic agents, antioxidants, ion scavengers, gettering agents, chain transfer agents, and the like.

  The adhesive film 20 may be a film having a single composition or may be a laminated film of two or more films having different compositions. When the film is composed of two or more kinds of films, for example, a relatively large amount of adhesive component is blended in the film bonded to the semiconductor wafer side, and the blending amount of the curable component is blended in the film bonded to the chip mounting portion. May be increased.

The thickness of the adhesive film 20 is usually 3 to 100 μm, preferably 3 to 95 μm, particularly preferably about 5 to 85 μm. In addition, when the convex electrode (bump) 12 is formed on the wafer surface to which the adhesive film is attached, the circuit surface is covered without generation of voids, and the bump penetrates the adhesive film. The ratio (H _B / T _A ) between the height (H _B ) and the thickness (T _A ) of the adhesive film 20 is preferably 1.0 / 0.3 to 1.0 / 0.95, more preferably 1.0 / 0.5 to 1.0 / 0.9, more preferably 1.0 / 0.6 to 1.0 / 0.85, particularly preferably 1.0 / 0.7 to 1.0 / It is in the range of 0.8. The average height (H _B ) of the bumps 12 is the height from the chip surface (the circuit surface excluding the bumps) to the top of the bumps.

  If the bump height is too high with respect to the thickness of the adhesive film, there is a gap between the chip surface (the circuit surface excluding the bump) and the chip mounting substrate, causing voids. On the other hand, if the adhesive film is too thick, the bumps do not penetrate the adhesive layer, causing a conduction failure.

(Support sheet 21)
The adhesive film 20 may be supplied to the attaching process with the semiconductor wafer in a state in which the adhesive film 20 is releasably supported on the support sheet 21 to be an adhesive sheet. Furthermore, the support sheet 21 may have a step absorption layer 22 in order to absorb the difference in height of the wafer circuit surface and attach the adhesive film to the wafer surface in close contact.

  The adhesive film 20 is laminated on the support sheet 21 so as to be peelable. The support sheet 21 may be a single-layer or multi-layer resin film called a base material 23 (see FIG. 1), and may further be a pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive layer 24 is formed on the resin film ( (See FIG. 2).

(Substrate 23)
The base material 23 is not particularly limited. For example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene / propylene copolymer, polypropylene, polybutene, polybutadiene, polymethylpentene, ethylene / vinyl acetate Polymer, ethylene / (meth) acrylic acid copolymer, ethylene / (meth) methyl acrylate copolymer, ethylene / (meth) ethyl acrylate copolymer, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer A resin film made of polyurethane film, ionomer or the like is used. Moreover, the level | step difference absorption layer mentioned later can also be used as a base material.

  Two or more kinds of these resin films can be laminated or used in combination. Furthermore, the thing which colored these resin films, or what gave printing etc. can be used. In addition, the resin film may be a sheet formed by extrusion forming a thermoplastic resin, or may be a stretched film, and a sheet obtained by thinning and curing a curable resin by a predetermined means. May be used.

  The thickness of the base material 23 is not specifically limited, Preferably it is 30-300 micrometers, More preferably, it is 50-200 micrometers. By setting the thickness of the base material 23 in the above range, sufficient flexibility is imparted to the adhesive sheet including the base material and the adhesive film, and therefore, good adhesiveness to the semiconductor wafer is exhibited.

  As shown in FIG. 1, when forming the adhesive film 20 directly on the base material 23, the surface tension of the surface which contacts the adhesive film 20 of the base material 23 becomes like this. Preferably it is 40 mN / m or less, More preferably, it is 37 mN / m m or less, particularly preferably 35 mN / m or less. The lower limit is usually about 25 mN / m. Such a substrate having a relatively low surface tension can be obtained by appropriately selecting the material, and can also be obtained by applying a release agent to the surface of the substrate and performing a release treatment. .

  As the release agent used for the release treatment, alkyd, silicone, fluorine, unsaturated polyester, polyolefin, wax, and the like are used. In particular, alkyd, silicone, and fluorine release agents are heat resistant. This is preferable.

  In order to release the surface of the substrate using the above release agent, the release agent can be applied as it is without solvent, or after solvent dilution or emulsification, using a gravure coater, Mayer bar coater, air knife coater, roll coater, etc. Then, the laminate coated with the release agent is either laminated at room temperature or under heating, cured by electron beam, wet lamination, dry lamination, hot melt lamination, melt extrusion lamination, coextrusion processing, etc. May be formed.

(Adhesive layer 24)
As shown in FIG. 2, the support sheet 21 may be an adhesive sheet having an adhesive layer 24 on the substrate 23. In this case, the said adhesive film 20 is laminated | stacked on the adhesive layer 24 so that peeling is possible. Therefore, as the pressure-sensitive adhesive layer 24, a weak adhesive layer may be used, or an energy beam curable layer whose adhesive force may be reduced by energy beam irradiation may be used. Further, the pressure-sensitive adhesive layer 24 may be formed by previously curing an energy ray-curable pressure-sensitive adhesive. The weakly adhesive layer is composed of various conventionally known adhesives (for example, rubber-based, acrylic-based, silicone-based, urethane-based, vinyl ether-based general-purpose pressure-sensitive adhesives, pressure-sensitive adhesives on the surface, energy rays, etc. Curable adhesive, thermal expansion component-containing adhesive, etc.).

  As the pressure-sensitive adhesive, acrylic and silicone are preferably used. In consideration of the peelability of the adhesive film, the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer 24 to the SUS plate at 23 ° C. is preferably 30 to 120 mN / 25 mm, and more preferably 50 to 100 mN / 25 mm. 60 to 90 mN / 25 mm is more preferable. When this adhesive force is too low, the adhesiveness between the adhesive film 20 and the pressure-sensitive adhesive layer 24 becomes insufficient, and the adhesive film and the pressure-sensitive adhesive layer may be peeled off. On the other hand, if the adhesive force is too high, the adhesive film 20 and the pressure-sensitive adhesive layer 24 are excessively adhered to each other, which causes a pickup failure.

  In the configuration of FIG. 2, in order to strengthen the adhesion between the base material 23 and the pressure-sensitive adhesive layer 24, the surface of the base material 23 on which the pressure-sensitive adhesive layer 24 is provided may be uneven by sandblasting or solvent treatment, if desired. Or oxidation treatment such as corona discharge treatment, electron beam irradiation, plasma treatment, ozone / ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment or the like. Moreover, primer treatment can also be performed.

  Although the thickness of the adhesive layer 24 is not specifically limited, Preferably it is 1-100 micrometers, More preferably, it is 2-80 micrometers, Most preferably, it is 3-50 micrometers.

(Step absorption layer 22)
When the height difference of the surface of the semiconductor wafer to which the adhesive film 20 is attached is large, it is preferable that the support sheet 21 has the step absorption layer 22. The adhesive film 20 may be directly laminated on the step absorption layer 22 (not shown). In addition, as shown in FIG. 3, when the support sheet has both the step absorption layer 22 and the pressure-sensitive adhesive layer 24 on the base material 23, the pressure-sensitive adhesive layer 24 is formed as the uppermost layer of the support sheet 21. The adhesive film 20 is preferably provided on the agent layer 24. Thereby, it becomes easy to control the peelability of the adhesive film 20 from the support sheet 21 by the pressure-sensitive adhesive layer 24.

  The thickness of the step absorption layer 22 is not particularly limited, but is preferably 10 to 400 μm, and the storage elastic modulus at 23 ° C. is preferably 0.2 to 6.0 MPa.

  The step absorption layer 22 exhibits unique viscoelasticity when a device region having bumps formed on the wafer surface is pressed, deforms rapidly according to the shape of the device, and stress due to the height difference (step) of the device. Therefore, even if the device is pressed, it is easy to avoid the device from being crushed. When the thickness of the step absorption layer 22 is less than 100 μm or when the storage elastic modulus at 23 ° C. of the step absorption layer 22 exceeds 6.0 MPa, the stress due to the height difference of the device may not be sufficiently relaxed. There is. On the other hand, when the thickness of the step absorption layer 22 exceeds 400 μm, or when the storage elastic modulus at 23 ° C. of the step absorption layer 22 is less than 0.2 MPa, the step absorption layer 22 is crushed when winding the adhesive sheet. There is a concern about the problem of being pushed out from.

  The thickness of the step absorption layer 22 is more preferably 30 to 350 μm, and particularly preferably 50 to 250 μm. Moreover, the storage elastic modulus at 23 ° C. of the step absorption layer 22 is more preferably 0.2 to 2.5 MPa, and particularly preferably 0.5 to 1.5 MPa. By setting the thickness of the step absorption layer 22 and the storage elastic modulus at 23 ° C. within the above range, the step on the wafer surface is embedded in the step absorption layer 22 and the step is easily absorbed.

  The step absorption layer 22 preferably satisfies the above thickness and storage elastic modulus, and the material thereof is not particularly limited, but preferably includes a cured product obtained by curing the urethane-containing curable composition. Examples of the urethane-containing curable resin composition include those in which an energy ray curable monomer is blended with a urethane (meth) acrylate oligomer as necessary, and those in which an energy ray curable monomer is blended in a non-reactive polyurethane. . As an example, a case will be described in which a cured product obtained by curing an energy beam of a blend containing a polyether polyol polyurethane and an energy beam curable monomer is used.

  The polyether polyol-based polyurethane may be a high molecular weight substance or an oligomer as long as it is obtained by polycondensation of a polyether polyol and a polyvalent isocyanate compound. When it is an oligomer, it preferably has a polymerizable functional group, and examples of the polymerizable functional group include a (meth) acryloyl group. Examples of such a polyether polyol-based polyurethane include polyether polyol-based urethane (meth) acrylate oligomers.

  The polyether polyol-based urethane (meth) acrylate oligomer is a compound having a structural unit derived from a polyether polyol in the molecule, an energy ray polymerizable (meth) acryloyl group, and a urethane bond. The polyether polyol urethane (meth) acrylate oligomer is obtained by reacting, for example, a terminal isocyanate urethane prepolymer obtained by reacting a polyether polyol compound and a polyvalent isocyanate compound with a (meth) acrylate having a hydroxy group. can get. By using a polyether polyol-based urethane (meth) acrylate oligomer having two or more (meth) acryloyl groups, tack of the step absorption layer 22 can be suppressed, and it is difficult to adhere to an operator or equipment.

  The polyether type polyol compound is not particularly limited, and may be a bifunctional diol, a trifunctional triol, or a tetrafunctional or higher polyol, but from the viewpoint of availability, versatility, reactivity, and the like. It is particularly preferred to use a diol. Accordingly, polyether type diols are preferably used.

  The polyether type diol is generally represented by HO-(-R-O-) n-H. Here, R is a divalent hydrocarbon group, preferably an alkylene group, more preferably an alkylene group having 1 to 6 carbon atoms, and particularly preferably an alkylene group having 2 or 3 carbon atoms. Among the alkylene groups having 1 to 6 carbon atoms, ethylene, propylene, butylene or tetramethylene is preferable, and ethylene or propylene is particularly preferable. Such an ether bond may have a structure derived from a ring-opening reaction of a cyclic ether such as ethylene oxide, propylene oxide, and tetrahydrofuran. By using such a polyether type polyol compound, the urethane (meth) acrylate oligomer contains a structural unit derived from the polyether type polyol compound. n is the number of repetitions of (—R—O—), preferably about 10 to 250, more preferably about 25 to 205, and particularly preferably about 40 to 185. When n is smaller than 10, the urethane bond density of the urethane (meth) acrylate oligomer is increased, and the storage elastic modulus at 23 ° C. of the step absorption layer 22 may be increased. On the other hand, if n is larger than 250 due to the polymer interaction between the polyether chains, there is a concern that the storage elastic modulus at 23 ° C. is difficult to decrease.

  The molecular weight of the polyether-type polyol compound is preferably about 1000 to 10000, and more preferably about 2000 to 8000. When the molecular weight is lower than 1000, the crosslinking density of the urethane (meth) acrylate oligomer is increased, and the storage elastic modulus at 23 ° C. of the step absorption layer 22 tends to increase. When the weight average molecular weight is too high, there is a concern that the storage elastic modulus at 23 ° C. is hardly lowered due to polymer interaction between the polyether chains.

  The molecular weight of the polyether-type polyol compound is the number of polyether-type polyol functional groups × 56.11 × 1000 / hydroxyl value [mgKOH / g], which is a value calculated from the hydroxyl value of the polyether-type polyol compound.

  The polyether-type polyol compound generates a terminal isocyanate urethane prepolymer having an ether bond (-(-R-O-) n-) introduced by urethanation with a polyvalent isocyanate compound.

  Examples of the polyvalent isocyanate compound include aliphatic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate; isophorone diisocyanate, norbornane diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, dicyclohexylmethane-2,4. Alicyclic diisocyanates such as' -diisocyanate, ω, ω'-diisocyanate dimethylcyclohexane; 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tolidine diisocyanate, tetramethylene xylylene diisocyanate, naphthalene-1, And aromatic diisocyanates such as 5-diisocyanate. Among these, it is preferable to use isophorone diisocyanate, hexamethylene diisocyanate, or xylylene diisocyanate because the viscosity of the urethane (meth) acrylate oligomer can be kept low and the handleability becomes good.

  In addition, you may use various well-known catalysts for the said urethanation reaction as needed. Examples of the catalyst include tin compounds such as dibutyltin oxide and stannous octylate, and alkoxytitanium such as tetrabutyl titanate and tetrapropyl titanate. When a catalyst is used, the amount used is not particularly limited, but about 10 to 500 ppm is reasonable from the viewpoint of reaction rate and reaction control. The reaction temperature of the esterification reaction is not particularly limited, but 150 to 300 ° C. is reasonable from the viewpoint of reaction rate and reaction control.

  A polyether polyol-based urethane (meth) acrylate obtained by reacting a hydroxyl-containing (meth) acrylate with a terminal isocyanate urethane prepolymer obtained by reacting the above polyether-type polyol compound with a polyvalent isocyanate compound. An oligomer is obtained.

  The (meth) acrylate having a hydroxy group is not particularly limited as long as it is a compound having a hydroxy group and a (meth) acryloyl group in one molecule, and known ones can be used. Specifically, for example, α-hydroxymethyl acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 5 -Alkylene ethers such as hydroxycyclooctyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, pentaerythritol tri (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate Group-containing (meth) acrylate; Hydroxy group-containing (meth) acrylamide such as N-methylol (meth) acrylamide; Vinyl alcohol, vinyl phenol, bisphenol The diglycidyl ester of A (meth) reacting the acrylic acid and the like reaction product obtained.

  As conditions for reacting the terminal isocyanate urethane prepolymer and the hydroxy group-containing (meth) acrylate, the terminal isocyanate urethane prepolymer and the hydroxy group-containing (meth) acrylate may be reacted in the presence of a solvent and a catalyst, if necessary. The reaction may be performed at about 60 to 100 ° C. for about 1 to 4 hours.

  Although the usage-amount of the (meth) acrylate which has a terminal isocyanate urethane prepolymer and a hydroxy group is not specifically limited, Usually, (equivalent of the isocyanate group of a terminal isocyanate urethane prepolymer) / (hydroxy of the (meth) acrylate which has a hydroxy group) The group equivalent) is preferably about 0.5 to 1.0.

  The weight average molecular weight Mw of the polyether polyol-based urethane (meth) acrylate oligomer thus obtained (polystyrene converted value by gel permeation chromatography, hereinafter the same) is not particularly limited, but is usually 35000. It is preferable to set it as about -100,000, It is more preferable to set it as about 40000-80000, It is especially preferable to set it as about 45000-70000. When the weight average molecular weight Mw is in such a range, it becomes easy to adjust the storage elastic modulus of the step absorption layer 22 at 23 ° C. to the above preferable range. By setting it as 100,000 or less, the resin viscosity of the urethane (meth) acrylate oligomer can be lowered, and the handling property of the coating liquid for film formation is improved.

  The resulting polyether polyol-based urethane (meth) acrylate oligomer has a photopolymerizable double bond in the molecule and has a property of being polymerized and cured by irradiation with energy rays to form a film. Such a polyether polyol-based urethane (meth) acrylate oligomer has a polyether polyol moiety having a relatively long chain length in the molecule, and the number of acryloyl groups serving as polymerization points is small compared to the molecular weight. The step absorption layer 22 including a cured product of a (meth) acrylate oligomer exhibits unique viscoelasticity.

  Said polyether polyol type urethane (meth) acrylate oligomer can be used individually by 1 type or in combination of 2 or more types. Since the film formation is often difficult only with the urethane (meth) acrylate oligomer as described above, the energy absorbing curable monomer is mixed to form a film, and then cured to obtain the step absorption layer 22. As the energy ray curable monomer, an acrylate ester compound having an energy ray polymerizable double bond in the molecule and having a relatively bulky group is preferably used.

  Specific examples of energy ray curable monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) acrylate. , T-butyl (meth) acrylate, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, nonyl (meth) ) Acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, hexadecyl (Meth) acrylates having 1-30 carbon atoms in the alkyl group such as meth) acrylate, octadecyl (meth) acrylate, eicosyl (meth) acrylate, etc .; isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (Meth) acrylate, dicyclopentenyloxy (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylate having an alicyclic structure such as adamantane (meth) acrylate; phenoxyethyl acrylate, phenylhydroxypropyl (meth) acrylate, (Meth) acrylate having an aromatic structure such as benzyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate; or tetrahydrofurfuryl (meth) (Meth) acrylates having a heterocyclic structure such as acrylate, (meth) acryloylmorpholine, N-vinylpyrrolidone, N-vinylcaprolactam; vinyl compounds such as styrene, hydroxyethyl vinyl ether, hydroxybutyl vinyl ether, N-vinylformamide It is done. Moreover, you may use polyfunctional (meth) acrylate as needed.

  Among these, from the point of compatibility with urethane (meth) acrylate oligomer, (meth) acrylate having an alicyclic structure having a relatively bulky group, (meth) acrylate having an aromatic structure, and heterocyclic structure (Meth) acrylate having

  10-500 mass parts is preferable with respect to 100 mass parts (solid content) of a urethane (meth) acrylate oligomer, and, as for the usage-amount of this energy-beam curable monomer, 30-400 mass parts is more preferable.

As the film forming method, a technique called casting film formation (cast film formation) can be preferably employed. Specifically, a liquid compound (a liquid product obtained by diluting a mixture of the above components with a solvent if necessary) is cast into a thin film on a process sheet, for example, and then the coating film is irradiated with energy rays for polymerization. Cured to form a film. According to such a manufacturing method, the stress applied to the resin during film formation is small, and the formation of fish eyes is small. Moreover, the uniformity of the film thickness is also high, and the thickness accuracy is usually within 2%. Specifically, ultraviolet rays, electron beams, etc. are used as the energy rays. Further, the irradiation amount is different depending on the type of the energy ray, for example, when ultraviolet rays are used, the ultraviolet intensity is 50~300mW / cm ^2, the amount of ultraviolet irradiation is preferably about 100~1200mJ / cm ^2.

  When ultraviolet rays are used as energy rays during film formation, it is possible to react efficiently by blending a photopolymerization initiator into the blend. Examples of such photopolymerization initiators include photopolymerization initiators such as benzoin compounds, acetophenone compounds, acylphosphinoxide compounds, titanocene compounds, thioxanthone compounds and peroxide compounds, and photosensitizers such as amines and quinones. Specific examples include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether.

  The use amount of the photopolymerization initiator is preferably 0.05 to 15 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass in total of the urethane (meth) acrylate oligomer and the energy ray curable monomer. Particularly preferred is 0.3 to 5 parts by mass.

  Moreover, you may add metal fillers, such as inorganic fillers, such as a calcium carbonate, a silica, and a mica, iron, and lead, in the above-mentioned compound. Further, in addition to the above components, the step absorption layer 22 may contain additives such as colorants such as pigments and dyes.

  The step absorption layer 22 containing a cured product obtained by curing such a urethane-containing curable composition may be laminated on the base material 23 after being formed on the process sheet. Alternatively, the step absorption layer 22 may be formed directly.

  Further, the step absorption layer 22 may include an olefin copolymer as a main component. Examples of the olefin copolymer include an ethylene / α-olefin copolymer such as TAFMER (registered trademark) manufactured by Mitsui Chemicals. The olefin copolymer forming the step absorption layer 22 of the present invention is an α-olefin copolymer containing at least two α-olefins selected from α-olefins having 2 to 12 carbon atoms as main unit components. It is preferable that

   Examples of the α-olefin having 2 to 12 carbon atoms include ethylene, propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, and 3-methyl. Examples include -1-pentene, 1-heptene, 1-octene, 1-decene, and 1-dodecene. Examples of combinations excellent in sticking suitability include ethylene / propylene copolymers, ethylene / 1-butene copolymers, propylene / 1-butene / triene copolymers of 5 to 12 carbon atoms, and ethylene / propylene copolymers. Examples thereof include a terpolymer of propylene / α-olefin having 4 to 12 carbon atoms, and a three-component copolymer of propylene · 1-butene · α-olefin having 5 to 12 carbon atoms. Moreover, said olefin type copolymer can be used individually or in combination of 2 or more types.

  The step absorption layer 22 preferably contains the olefin copolymer as a main component, and the content thereof is usually about 60 to 100% by mass, and preferably about 70 to 100% by mass.

  As a method of forming the step absorption layer 22 containing such an olefin copolymer as a main component on the base material 23, for example, an extrusion molding method may be mentioned.

(Semiconductor chip manufacturing method)
Next, the manufacturing method of the semiconductor chip with an adhesive film using the above adhesive film will be described with reference to methods 1 to 3 as non-limiting specific examples. In the following, an example in which an adhesive sheet in which the adhesive film 20 is supported on the support sheet 21 is used will be described. However, the adhesive film 20 is not supported without using the support sheet 21. May be. The support sheet 21 may be peeled off at any stage after the adhesive film 20 is pasted. The adhesive film may be partially cured. In this case, partial curing may be performed before the adhesive film is applied to the wafer circuit surface, or partial curing may be performed after the adhesive film is applied. The partial curing of the adhesive film 20 may be performed, for example, by heating the adhesive film to be in a B-stage state. When the adhesive film contains an energy ray curable component, it can also be performed by energy ray irradiation. In the figure, the support sheet 21 is described as a single layer. However, the support sheet 21 may be a single-layer resin sheet of the base material 23 or a multilayer resin sheet. The adhesive sheet which consists of the adhesive layer 24 may be sufficient, and the structure which has the level | step difference absorption layer 22 may be sufficient.

(Method 1)
Semiconductor device manufacturing method 1 includes the following steps (1a) to (1f). In semiconductor device manufacturing method 1, step (1b) is performed after step (1a) or simultaneously with step (1a).
(1a) The process of sticking the adhesive film surface of the adhesive sheet in which the adhesive film 20 for die bonding is detachably supported on the support sheet 21 to the circuit surface of the semiconductor wafer 10 on which the circuit is formed under reduced pressure ,
(1b) A step of attaching the surface protection sheet 25 to the semiconductor wafer 10 via the adhesive sheet 21 or the adhesive film 20;
(1c) grinding the back surface of the semiconductor wafer 10;
(1d) The process of sticking the adhesive sheet 26 on the back surface of the semiconductor wafer 10,
(1e) The process of peeling the surface protection sheet 25,
(1f) The process of peeling the support sheet 21, and (1g) The process of dividing the semiconductor wafer 10 and the adhesive film 20 for die bonding into pieces for every circuit.
Hereinafter, each step will be described.

(1a) Step (1a) In step (1a), the adhesive film surface of the adhesive sheet in which the die bonding adhesive film 20 is releasably supported on the support sheet 21 is used as the circuit surface of the semiconductor wafer 10 on which the circuit is formed. (See Fig. 4). The specific method for attaching the adhesive film under reduced pressure is as described above.

  In the methods 1 to 3, the die bonding adhesive film 20 and the support sheet 21 may be attached to the wafer surface in a pre-cut form that has been cut in substantially the same shape as that of the semiconductor wafer 10, and a planar shape larger than the wafer. After attaching the adhesive film, the outer peripheral portion may be cut along the outer diameter of the wafer. After attaching the adhesive sheet, the support sheet 21 may be peeled off (step (1f)), or the support sheet may be left.

  Examples of the semiconductor wafer 10 include conventionally used semiconductor wafers such as a silicon semiconductor wafer and a gallium / arsenic semiconductor wafer, but are not limited thereto, and various semiconductor wafers can be used. Formation of a circuit on the wafer surface can be performed by various methods including conventionally used methods such as an etching method and a lift-off method. In the wafer circuit formation process, a predetermined circuit is formed. Further, it is desirable that convex electrodes (bumps) 12 used for conduction with the chip mounting substrate are formed on the circuit surface. The height and diameter of the bump 12 vary depending on the design of the semiconductor device, but generally the height is about 10 to 100 μm and the diameter is about 20 to 100 μm. Such bumps 12 are often formed from a metal such as gold, copper, or solder. The shape of the bump 12 is not particularly limited, and examples thereof include a columnar shape and a spherical shape, and a shape in which a hemisphere is placed on the tip of a column as shown in FIG.

(1b) Step (1b) In the step (1b), a surface protective sheet 25 is attached to the surface of the adhesive sheet on the support sheet 21 side (see FIG. 5). When the support sheet 21 is peeled off, the surface protection sheet 25 is attached to the adhesive film 20. The surface protective sheet 25 is stuck to hold the wafer 10 and protect the circuit surface in a back surface grinding step ((1c) step) described later.

  As the surface protective sheet 25, various pressure-sensitive adhesive sheets used for this kind of application are used without particular limitation. In methods 1 to 3, when the surface protective sheet 25 is adhered to the support sheet 21, in the subsequent step, it is preferable to peel the surface protective sheet in a state integrated with the support sheet. It is preferable to use a highly adhesive surface protective sheet. Further, when the surface protective sheet 25 is adhered to the adhesive film 20, the surface protective sheet 25 is peeled off at the interface between the surface protective sheet 25 and the adhesive film 20 in the subsequent process. It is preferable to use a peelable surface protective sheet.

  The surface protective sheet 25 is preferably used in a shape substantially equal to the shape of the wafer 10. In this case, the surface protection sheet 25 may be cut in advance in substantially the same shape as the wafer 10, and after attaching the surface protection sheet 25 to the wafer 10 via the adhesive sheet, the excess sheet is attached along the outer periphery of the wafer 10. It may be cut and removed. Moreover, the thickness of the surface protection sheet 25 is 20-1000 micrometers normally, Preferably it is 50-250 micrometers. When the surface protection sheet 25 has an adhesive layer, among the above thicknesses, the thickness of the adhesive layer is 5 to 500 μm, preferably 10 to 100 μm. The method for attaching the surface protection sheet is not particularly limited, and is performed by a general-purpose method using a tape mounter or the like.

  Moreover, the adhesive sheet which consists of the adhesive film 20 and the support sheet 21 can be previously laminated | stacked on the surface protection sheet 25, and the said (1a) process and (1b) process can also be performed simultaneously. Further, the adhesive film 20 may be directly laminated on the surface protection sheet 25. In this case, the support sheet 21 in the drawings or the like does not exist, and the surface protection sheet 25 also serves as the support sheet 21.

(1c) Step (1c) In the step (1c), the back surface of the semiconductor wafer is ground to reduce the thickness of the wafer 10 (see FIG. 6). The back surface grinding of the wafer 10 is performed by a method using a grinder or the like. The thickness of the wafer 10 after back grinding is not particularly limited, but is usually about 50 to 300 μm. Here, the thickness of the wafer refers to the thickness of the portion where no bump is formed.

(1d) Step (1d) In the step (1d), an adhesive sheet 26 is attached to the back surface of the semiconductor wafer 10 (see FIG. 7). What is necessary is just to use what is used as a well-known dicing sheet as the adhesive sheet 26. FIG. The method for attaching the adhesive sheet 26 is not particularly limited, and is performed by a general-purpose method using a tape mounter or the like. As a pressure-sensitive adhesive sheet typified by a dicing sheet, for example, a pressure-sensitive adhesive sheet 26 having a pressure-sensitive adhesive layer 28 on a substrate 27 is generally used. However, the pressure-sensitive adhesive sheet is not limited to this, and various pressure-sensitive adhesive sheets can be used.

(1e) Step In the step (1e), the surface protective sheet 25 is peeled off.

(1f) Step (1f) In step (1f), the support sheet 21 is peeled off. As described above, the step (1f) may be performed before the step (1b). Further, when the support sheet 21 is left, it is preferable to peel off the support sheet 21 simultaneously with the surface protection sheet 25 (see FIG. 8). However, after the surface protection sheet 25 is peeled off, the support sheet 21 is peeled off. May be.

(1g) Step (1g) In the step (1g), the semiconductor wafer 10 and the die bonding adhesive film 20 are separated for each circuit, and the semiconductor chip 11 having the die bonding adhesive film 20 on the circuit surface is obtained (see FIG. 9). That is, in the step (1g), the laminated body of the semiconductor wafer 10 and the adhesive film 20 is diced for each circuit formed on the wafer surface.

  Dicing is performed so that the wafer 10 and the adhesive film 20 are cut together. The dicing method is not particularly limited. For example, as shown in FIG. 9, when dicing the wafer, the outer peripheral portion of the adhesive sheet 26 is fixed by the ring frame 29, and then a rotating round blade such as a dicing blade 30 is used. A method for forming a wafer into a chip by a known method may be used. The depth of cut into the pressure-sensitive adhesive sheet 26 by dicing may be 0 to 30 μm from the interface between the wafer 10 and the pressure-sensitive adhesive sheet 26 as long as the adhesive film 20 and the wafer 10 are completely cut. By reducing the amount of cut into the base material 27, melting of the base material 27 due to friction of the dicing blade 30 and generation of burrs and the like in the base material 27 can be suppressed. Moreover, you may cut | disconnect the wafer 10 and the adhesive film 20 using a laser beam. At this time, full-cut dicing using laser light may be used, or a laser is focused inside the wafer to form a modified region layer, and dicing is performed using this modified region layer as a starting point. It may be. In the latter method, the adhesive film may not be cut. In this case, the adhesive sheet 26 may be expanded and the adhesive film may be cut by the expanding force.

  Thereafter, the adhesive sheet 26 and the semiconductor chip 11 are peeled off by picking up the diced semiconductor chip 11 with an adhesive film by a general-purpose means such as a collet. As a result, as shown in FIG. 10, the semiconductor chip 11 (semiconductor chip 11 with an adhesive film) having the adhesive film 20 for die bonding on the circuit surface is obtained. Prior to the pickup, the pressure-sensitive adhesive sheet 26 is expanded and the chip interval is increased, so that the pickup can be performed more easily.

(Method 2)
The semiconductor device manufacturing method 2 includes the following steps (2a) to (2f). In the semiconductor device manufacturing method 2, the step (2e) is performed after the step (2d).
(2a) A step of attaching the surface protection sheet 25 to the circuit surface of the semiconductor wafer 10 on which a circuit is formed on the surface;
(2b) grinding the back surface of the semiconductor wafer 10;
(2c) A process of attaching the adhesive sheet 26 to the back surface of the semiconductor wafer 10;
(2d) a step of peeling the surface protection sheet 25 from the circuit surface of the semiconductor wafer 10;
(2e) The process of sticking the adhesive film surface of the adhesive sheet in which the die bonding adhesive film 20 is releasably supported on the support sheet 21 to the circuit surface of the semiconductor wafer 10 on which the circuit is formed under reduced pressure ,
(2f) A step of dividing the semiconductor wafer 10 and the die bonding adhesive film 20 into pieces for each circuit.
Hereinafter, each step will be described.

(2a) Step (2a) In the step (2a), a surface protective sheet 25 is attached to the circuit surface of the semiconductor wafer 10 on which a circuit is formed (see FIG. 11). The semiconductor wafer 10 and the surface protection sheet 25 are the same as described above. The surface protection sheet 25 may be affixed to the wafer surface in a pre-cut form that has been cut in substantially the same shape as the semiconductor wafer 10, and after adhering an adhesive film having a planar shape larger than the wafer, the surface protection sheet 25 follows the outer diameter of the wafer. The outer periphery may be excised.

(2b) Step (2b) In the step (2b), the back surface of the semiconductor wafer is ground to reduce the thickness of the wafer 10 (see FIG. 12). The specific method is the same as that in the step (1c).

(2c) Step (2c) In the step (2c), the adhesive sheet 26 is attached to the back surface of the semiconductor wafer 10. The adhesive sheet 26 is the same as described above. In order to stabilize the process, the pressure-sensitive adhesive layer 28 may be affixed to the ring frame 29 at the outer periphery thereof (see FIG. 13).

(2d) Step (2d) In the step (2d), the surface protection sheet 25 is peeled from the circuit surface of the semiconductor wafer 10. As a result, the semiconductor wafer 10 having the bumps 12 laminated on the adhesive sheet 26 is obtained (see FIG. 14).

(2e) Step (2e) In the step (2e), the adhesive film surface of the adhesive sheet in which the die bonding adhesive film 20 is releasably supported on the support sheet 21 is attached to the circuit surface of the semiconductor wafer 10 under reduced pressure ( FIG. 15). The specific method for attaching the adhesive film under reduced pressure is as described above.

(2f) Step (2f) In the step (2f), the semiconductor wafer 10 and the die bonding adhesive film 20 are separated for each circuit, and the chip 11 having the die bonding adhesive film on the circuit surface is obtained. The method is not particularly limited, but it is preferable to use an adhesive sheet in which the adhesive sheet 20 is peeled and the die bonding adhesive film 20 is releasably supported on the support sheet 21 as a wafer fixing tape during dicing. . That is, it is preferable to perform dicing after transferring the wafer onto the adhesive sheet. The wafer singulation method may be a method using a dicing blade, or may be a method using laser light.

  When the obtained chip 11 is separately transferred to the pressure-sensitive adhesive sheet after the step (2f), it is the same as FIG. 9 referred to in the step (1f). The subsequent pick-up process is the same as described above, and the specific mode is also the same as in FIG.

(Method 3)
The semiconductor device manufacturing method 3 includes the following steps (3a) to (3f).
(3a) The process of sticking the adhesive film surface of the adhesive sheet by which the adhesive film 20 for die bonding is detachably carry | supported on the support sheet 21 on the circuit surface of the semiconductor wafer 10 in which the circuit was formed on the surface under pressure reduction ,
(3b) forming a groove 31 having a depth shallower than the wafer thickness in the semiconductor wafer 10;
(3c) A step of attaching the surface protective sheet 25 to the semiconductor wafer 10 directly or via the adhesive sheet 21 or the adhesive film 20;
(3d) a step of grinding the back surface of the semiconductor wafer 10 to reduce the thickness of the wafer and finally dividing it into individual chips 11;
(3e) The process of sticking the adhesive sheet 26 on the back surface of the group of divided chips 11,
(3f) The process of peeling the surface protection sheet 25.
(3g) The process of peeling the support sheet 21.
Hereinafter, each step will be described.

Step (3a) Step (3a) is the same as step (1a) (see FIG. 4).

(3b) Step (3b) In the step (3b), a groove 31 having a depth shallower than the thickness of the wafer is formed on the circuit surface of the semiconductor wafer 10 on which a circuit is formed (see FIG. 16). At this time, when the adhesive sheet is stuck on the surface of the semiconductor wafer 10, that is, when the step (3b) is performed after the step (3a) and before the step (3g). Then, the adhesive sheet (the adhesive film 20 and the support sheet 21) is completely cut (see FIG. 16). Moreover, when the adhesive film 20 is affixed, that is, when the step (3b) is performed after the steps (3a) and (3g), the adhesive film is completely cut. When the step (3b) is performed before the step (3a), the adhesive sheet or the adhesive film 20 does not exist on the surface of the semiconductor wafer 10.

  The method for forming the groove 31 is not particularly limited. For example, the wafer 10 is attached to a dicing tape, and the peripheral portion of the dicing tape is fixed by a ring frame, or the circuit surface side of the wafer 10 is fixed to a suction table. By using a known technique such as using a rotating round blade such as a dicing blade, the adhesive sheet can be completely cut to form a groove 31 having a depth shallower than the thickness of the wafer.

(3c) In the step (3c), the surface is formed on the surface on which the groove is formed (the surface on the support sheet 21 or the adhesive film 20 side when the adhesive sheet or the adhesive film 20 is attached to the surface of the semiconductor wafer 10). A protective sheet 25 is affixed (see FIG. 17 for the case where an adhesive sheet is affixed to the surface of the semiconductor wafer 1). The specific example of the surface protection sheet 25 and its sticking method are the same as the above.

(3d) Step (3d) In the step (3d), the back surface of the semiconductor wafer 10 is ground to reduce the thickness of the wafer and to be divided into individual chips 11 (an adhesive sheet is stuck on the surface of the semiconductor wafer 10). For the case, see FIG. 18). Wafer backside grinding is performed by a method using a grinder or the like. The wafer is thinned by back grinding, and the wafer is divided into individual chips 11 when the wafer reaches the bottom of the groove 31 formed in the step (3b).

(3e) Step (3e) In step (3e), the adhesive sheet 26 is pasted on the back surface (grind surface side) of the group of divided chips 11 (when the adhesive sheet is pasted on the surface of the semiconductor wafer 10). reference). The specific example of the adhesive sheet 26 and its sticking method are the same as the above. Moreover, in order to ensure operability and facilitate expansion, it is preferable to fix the peripheral portion of the adhesive sheet 26 with a ring frame 29.

(3f) In the step (3f), the surface protective sheet 25 is peeled off.

(3g) In the step (3g), the support sheet 21 is peeled off. In the step (3f), the step (3g) may be performed simultaneously with the step (3f) by peeling the surface protective sheet 25 and the support sheet 21 at the same time. In this case, when the step (3b) is performed after the step (3a), the separated support sheet 21 cut in the step (3b) is peeled off.

Here, the order of performing the steps (3a) to (3g) will be described.
The step (3a) is performed before the step (3c) or at the same time as the step (3c), but before and after the steps (3a) and (3b) are arbitrary. About (3b) process-(3f) process, it is performed in order of (3b) process, (3c) process, (3d) process, (3e) process, and (3f) process as needed.

As described in the method 1, the step (3g) can be performed after the step (3a) and before the step (3c). When the step (3g) is not performed before the step (3c), the support sheet 21 is sandwiched between the semiconductor wafer 10 and the surface protection sheet 25 until the step (3f). Only can not be peeled off. Therefore, in this case, the step (3g) is performed simultaneously with the step (3f) or after the step (3f).
FIG. 20 shows a chart for several types of the order of these steps.

  When the step (3a) is performed simultaneously with the step (3c), an adhesive sheet composed of the adhesive film 20 and the support sheet 21 may be laminated on the surface protection sheet 25 in advance, as in the method 1. The adhesive film 20 may be directly laminated on the surface protection sheet 25 that also serves as the support sheet 21. In this case, since the step (3c) is performed after the step (3b), the step (3a) is also performed after the step (3b). Therefore, it is preferable to perform the process (3h) described below.

  When the step (3a) is performed after the step (3b), the adhesive film 20 is not cut simultaneously with the formation of the groove in the step (3b). Therefore, even after implementation of the steps (3a) to (3g), the adhesive film 20 is not separated into pieces (see FIG. 21). Therefore, it is preferable to further perform a step of (3h) cutting the die bonding adhesive film 20 corresponding to the space between the chips in a plan view in the same shape as the chips. When the step (3h) is performed, the step (3h) is performed after the step (3d).

(3h) Step (3h) In the step (3h), the die bonding adhesive film 20 corresponding to the space between the chips in plan view is cut into the same shape as the chips 11 (see FIG. 21). The cutting method of the adhesive film 20 is not specifically limited, For example, the method (Method A) which cuts the adhesive film 20 for die bonding in the same shape as the chip | tip 11 by expanding the surface protection sheet 25 or the adhesive sheet 26 is mentioned. It is done. Further, there is a method (Method B) in which the die bonding adhesive film 20 is cut into the same shape as the chip 11 by irradiating the die bonding adhesive film 20 corresponding to the space between the chips in a plan view. It is done.

  In the method A, by maintaining the die bonding adhesive film 20 at 15 ° C. or lower, preferably −10 to 10 ° C. during the expansion, the stress (expanding force) generated by the expansion is applied to the adhesive film 20 between the chips. It tends to propagate and it becomes easy to divide the adhesive film into chips. The adhesive film that is in close contact with the chip 10 is not stretched because the deformation is constrained by the chip, but the deformation of the adhesive film located between the chips is not constrained, and is thus cut into substantially the same shape as the chip by stretching. The expansion is preferably performed at a speed of 5 to 600 mm / min. When the method A is adopted, it is preferable to peel the support sheet 21 in advance (step (3g)) in order to propagate the expanding force of the surface protective sheet 25 or the pressure-sensitive adhesive sheet 26 to the adhesive film 20. When expanding the surface protection sheet 25, it is preferable to complete the step (3g) prior to the step (3c).

  The support sheet 21 and the surface protection sheet 25 are peeled off, and the step (3h) that is necessary in some cases is performed, so that the same situation as in FIG. . The subsequent pick-up process is the same as described above, and the specific mode is also the same as in FIG.

  Next, the semiconductor chip with an adhesive film obtained by the above-described methods 1 to 3 is picked up. The pick-up of the semiconductor chip with the adhesive film may be performed directly from the adhesive sheet 26, or after the semiconductor chip 11 with the adhesive film is transferred from the adhesive sheet 26 to another adhesive sheet, the semiconductor with the adhesive film is transferred from the other adhesive sheet. A chip may be picked up. As such another pressure-sensitive adhesive sheet, a pressure-sensitive adhesive sheet having appropriate pressure-sensitive adhesiveness and removability is preferable, and in particular, an ultraviolet curable pressure-sensitive adhesive sheet that has been conventionally used as a dicing sheet is preferably used.

  The semiconductor chip with an adhesive film can be picked up by a known method using a suction collet or the like. Moreover, you may push up the chip | tip with an adhesive film from the back surface side of the adhesive sheet 26 or another adhesive sheet with a push-up pin as needed.

  The picked-up semiconductor chip with an adhesive film may proceed to the next process as it is or through a chip reversal process, or once stored on a transfer tape or in a storage container and used in the next process as necessary. Also good.

  Then, the semiconductor chip 11 with the adhesive film is placed on a predetermined position such as an electrode portion of the chip mounting substrate via the adhesive film 20. Specifically, a chip having the adhesive film 20 on the circuit surface side is placed on a predetermined chip mounting substrate by a face-down method. In a chip having bumps, the bumps are placed so as to face corresponding terminal portions on the chip mounting substrate.

  Thereafter, the die-bonded semiconductor chip with an adhesive film is heated to fix the chip to the chip mounting substrate. As described above, the adhesive film 20 is formed of a B-stage resin, an adhesive, a thermoplastic resin, or the like that exhibits adhesiveness by heating. By heating these under predetermined conditions, if it is a B-stage resin, the adhesiveness is manifested by curing of the resin, and if it is an adhesive, the adhesiveness is exhibited by curing of the thermosetting resin contained therein. To express. Moreover, if it is a thermoplastic resin, adhesive force will be expressed by heat sealing.

  After die bonding (flip chip bonding) in this way, a semiconductor device can be obtained through a normal process such as resin sealing, if necessary.

  As mentioned above, although the manufacturing method of the semiconductor chip of this invention was demonstrated along drawing, this invention is not limited to the manufacturing method of the semiconductor chip of the said structure, It applies to the manufacturing method of the semiconductor chip which has various structures. it can.

10: Semiconductor wafer 11: Semiconductor chip 12: Convex electrode (bump)
20: Die bonding adhesive film 21: Support sheet 22: Step absorption layer 23: Base material 24: Adhesive layer 25: Surface protective sheet 26: Adhesive sheet 27: Adhesive sheet base material 28: Adhesive sheet adhesive layer 29 : Ring frame 30: Dicing blade 31: Groove

Claims (10)

A process of applying an adhesive film for die bonding to a circuit surface of a semiconductor wafer having a circuit formed on the surface under reduced pressure;
In a method for manufacturing a semiconductor chip, including a step of obtaining a chip having a semiconductor wafer and a die bonding adhesive film for each circuit and obtaining a chip having a die bonding adhesive film on a circuit surface ,
A die-bonding adhesive film consisting of a support sheet and the die-bonding adhesive film detachably supported thereon is applied to a circuit surface of a semiconductor wafer having a circuit formed on the surface under reduced pressure. And
Then, including the step of peeling the support sheet from the adhesive film for die bonding,
The support sheet of the adhesive sheet has a step absorption layer, and an adhesive film for die bonding is detachably supported on the step absorption layer,
The semiconductor chip manufacturing method, wherein the step absorption layer has a thickness of 50 to 400 μm and a storage elastic modulus at 23 ° C. of 0.2 to 6.0 MPa .   The manufacturing method of the semiconductor chip of Claim 1 in which the said level | step difference absorption layer contains the hardened | cured material obtained by hardening a urethane-containing curable composition.   The manufacturing method of the semiconductor chip of Claim 1 or 2 with which the said level | step difference absorption layer contains an olefin type copolymer as a main component.   The manufacturing method of the semiconductor chip in any one of Claims 1-3 in which the said support sheet has a level | step difference absorption layer and an adhesive layer in this order on a base material.   5. The semiconductor according to claim 1, wherein the die-bonding adhesive film and the support sheet are attached to a circuit surface of the semiconductor wafer in a pre-cut form that has been pre-cut into approximately the same shape as the semiconductor wafer. Chip manufacturing method.   The die bonding adhesive film and the support sheet are cut off along the outer diameter of the semiconductor wafer after the planar adhesive film larger than the semiconductor wafer is attached to the circuit surface of the semiconductor wafer. The method for manufacturing a semiconductor chip according to claim 1. The manufacturing method of the semiconductor chip in any one of Claims 1-6 by which a convex electrode is provided in the circuit surface of a semiconductor wafer. The manufacturing method of the semiconductor chip in any one of Claims 1-7 which perform the process of sticking the adhesive film for die-bonding under reduced pressure which makes a pressure environment 50-400 Pa.   Before the step of applying an adhesive film for die bonding under reduced pressure to the circuit surface of a semiconductor wafer having a circuit formed on the surface,
  Attaching a surface protection sheet to the circuit surface of the semiconductor wafer;
  Grinding the back surface of the semiconductor wafer;
  Attaching an adhesive sheet to the back surface of the semiconductor wafer; and
  The manufacturing method of the semiconductor chip in any one of Claims 1-8 including the process of peeling this surface protection sheet from the circuit surface of this semiconductor wafer.   Applying a die bonding adhesive film to a circuit surface of a semiconductor wafer having a circuit formed on the surface under reduced pressure;
  Forming a groove having a depth shallower than the thickness of the wafer in the semiconductor wafer;
  A step of attaching a surface protective sheet to the semiconductor wafer directly or via the adhesive sheet or the adhesive film;
  A process of reducing the thickness of the wafer by grinding the back surface of the semiconductor wafer and finally dividing the wafer into individual chips;
  Attaching an adhesive sheet to the back of the group of divided chips, and
  The manufacturing method of the semiconductor chip in any one of Claims 1-9 including the process of peeling this surface protection sheet.

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