JP2009231570A - Wafer processing tape - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wafer processing tape which can be used in an expanding step for dividing an adhesive layer, and having a small anisotropy in expandability. <P>SOLUTION: The wafer processing tape 10 is an expandable wafer processing tape used in dividing the adhesive layer 13 along a chip by its expansion, and has a base material film 11 having a plurality of resin layers 11a, 11b laminated so that the film forming directions (MD) may not coincide with each other, and an adhesive layer 12 provided on the base material film 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an expandable wafer processing tape used when an adhesive layer is divided along a chip by an expand.

  In the manufacturing process of a semiconductor device such as an IC, a wafer processing tape is formed by sticking an adhesive and stretchable wafer processing tape to the back surface of a semiconductor wafer on which a circuit pattern is formed, and then dividing the semiconductor wafer into chips. Die bonding process for expanding semiconductor tape, picking up divided chips, bonding the picked-up chips to a lead frame, package substrate, etc., or stacking and bonding semiconductor chips together in a stacked package A (mount) process is performed.

  As a wafer processing tape used in the manufacturing process of the semiconductor device, in addition to a dicing tape in which an adhesive layer is provided on a base film, a dicing die bonding tape in which an adhesive layer is formed on the dicing tape is provided. Proposed and already in practical use.

  In general, when using a dicing die bonding tape, first, the adhesive layer of the dicing die bonding tape is fixed to the back surface of the semiconductor wafer to fix the semiconductor wafer, and then the semiconductor wafer and the adhesive layer are attached using a dicing blade. Dicing on a chip basis. Then, the expanding process which expands the space | interval of chips | tips is implemented by expanding a tape in the circumferential direction. This expanding step is performed in the subsequent pick-up step in order to improve chip recognition by a CCD camera or the like and to prevent chip breakage caused by contact between adjacent chips when picking up a chip. . In the pickup process, the chip is peeled off from the adhesive layer together with the adhesive layer and picked up. In this way, using a dicing die bonding tape makes it possible to directly bond a chip with an adhesive layer to a lead frame, a package substrate, etc. The step of bonding the bonding film can be omitted.

  However, in the dicing process, if the semiconductor wafer and the adhesive layer are diced together using the dicing blade as described above, not only the wafer cutting waste but also the adhesive cutting waste is generated. Since the cutting waste of the adhesive layer itself has an adhesive function, when the cutting waste is clogged in the dicing groove of the wafer, chips stick to each other to cause a pick-up failure and the semiconductor device manufacturing yield decreases.

  In order to solve the above problems, in the dicing process, only the semiconductor wafer is diced with a blade, and in the expanding process, the dicing die bonding tape is expanded to divide the adhesive layer corresponding to each chip. Has been proposed (for example, paragraph numbers “0055” to “0056” of Patent Document 1). According to the method for dividing the adhesive layer using the tension at the time of expansion, no cutting waste of the adhesive is generated, and there is no adverse effect in the pickup process.

  In recent years, a so-called stealth dicing method that can cut a wafer in a non-contact manner using a laser processing apparatus has been proposed as a semiconductor wafer cutting method.

  For example, in Patent Document 2, as a stealth dicing method, a semiconductor is obtained by irradiating laser light with focused light inside a semiconductor substrate on which a sheet is attached with a die bond resin layer (adhesive layer) interposed therebetween. A step of forming a modified region by multiphoton absorption inside the substrate, forming a portion to be cut in the modified region, and expanding (expanding) the sheet so that the semiconductor substrate and the die bond resin are along the portion to be cut. A method of cutting a semiconductor substrate comprising a step of cutting a layer is disclosed.

  As another method of cutting a semiconductor wafer using a laser processing apparatus, for example, Patent Document 3 discloses a process of mounting an adhesive film (adhesive layer) for die bonding on the back surface of a semiconductor wafer, A process of attaching an extensible protective adhesive tape to the adhesive film side of the semiconductor wafer on which the adhesive film is mounted, and irradiating a laser beam along the street from the surface of the semiconductor wafer to which the protective adhesive tape is attached. The process of dividing into semiconductor chips, the process of expanding (expanding) the protective adhesive tape to give tensile force to the adhesive film, and breaking the adhesive film for each semiconductor chip, and the broken adhesive film are attached There has been proposed a semiconductor wafer dividing method including a step of removing a semiconductor chip from a protective adhesive tape.

According to these semiconductor wafer cutting methods described in Patent Document 2 and Patent Document 3, since the semiconductor wafer is cut in a non-contact manner by laser light irradiation and tape expansion, the physical load on the semiconductor wafer is small, The semiconductor wafer can be cut without generating wafer chipping (chipping) as in the case of the current mainstream blade dicing. Moreover, since the adhesive layer is divided by the expand, cutting waste of the adhesive layer is not generated. For this reason, it attracts attention as an excellent technique that can replace blade dicing.
JP 2007-5530 A JP 2003-338467 A JP 2004-273895 A

  In the case where the adhesive layer is divided by an expand as described in Patent Documents 1 to 3, the wafer processing tape to be used has a base for reliably dividing the adhesive layer along the semiconductor chip. A uniform and isotropic expandability of the material film is required. This is because when a location where expansion is insufficient locally occurs in the base film, sufficient tensile force is not propagated to the adhesive layer at that location, and the adhesive layer cannot be divided.

  However, in general, a base film formed by an extrusion method or the like is subjected to stress in the film forming direction (Machine direction: MD), and the stress in the direction perpendicular to the film direction (Traverse direction: TD) is suppressed. As a result, anisotropy occurs in the expandability of the formed film, and as a result, there is a problem in that the dividing property of the adhesive layer is different between MD and TD of the base film, and the adhesive layer cannot be divided 100%.

  Then, an object of this invention is to provide the tape for wafer processing with a small expandable anisotropy which can be used in the expanding process which divides | segments an adhesive bond layer.

  A first aspect of the present invention is an expandable wafer processing tape used when dividing an adhesive layer along a chip by an expand so that the film forming directions (MD) of the tape do not coincide with each other. A wafer processing tape comprising: a base film composed of a plurality of laminated resin layers; and an adhesive layer provided on the base film.

  According to a second aspect of the present invention, in the wafer processing tape according to the first aspect, the base film is laminated in such a manner that the film forming directions (MD) thereof are approximately 90 °. It is characterized by being a resin layer.

  According to a third aspect of the present invention, in the wafer processing tape according to the second aspect, each of the two resin layers has a thickness of 50 to 200 μm.

  According to a fourth aspect of the present invention, in the wafer processing tape according to the second or third aspect, an upper layer in contact with the pressure-sensitive adhesive layer among the two resin layers is defined by JIS K7206. It is characterized by comprising a thermoplastic resin having a Vicat softening point of 50 ° C. or higher and lower than 80 ° C.

  According to a fifth aspect of the present invention, in the wafer processing tape according to any one of the second to fourth aspects, an adhesive layer is further provided between the two resin layers.

  According to a sixth aspect of the present invention, in the wafer processing tape according to any one of the second to fourth aspects, an adhesive layer is further provided between the two resin layers.

  According to a seventh aspect of the present invention, in the wafer processing tape according to any one of the first to sixth aspects, an adhesive layer is further provided on the pressure-sensitive adhesive layer.

According to an eighth aspect of the present invention, in the wafer processing tape according to any one of the first to seventh aspects, the wafer processing tape comprises:
(A) irradiating a laser beam to a part to be divided of a semiconductor wafer in advance, and forming a modified region by multiphoton absorption inside the wafer;
(B) including a step of laminating the adhesive layer of the wafer processing tape on the back surface of the semiconductor wafer in a random order;
(C) expanding the wafer processing tape to divide the semiconductor wafer and the adhesive layer along a dividing line to obtain a plurality of semiconductor chips with an adhesive layer. It is used for the method.

A ninth aspect of the present invention is the wafer processing tape according to any one of the first to seventh aspects, wherein the wafer processing tape comprises:
(A) bonding the adhesive layer of the wafer processing tape to the back surface of the semiconductor wafer;
(B) irradiating a laser beam along a dividing line from the surface of the semiconductor wafer to divide into individual semiconductor chips;
And (c) dividing the adhesive layer into the semiconductor chips by expanding the wafer processing tape to obtain a plurality of chips with adhesive layers. It is characterized by.

A tenth aspect of the present invention is the wafer processing tape according to any one of the first to seventh aspects, wherein the wafer processing tape comprises:
(A) bonding the adhesive layer of the wafer processing tape to the back surface of the semiconductor wafer;
(B) cutting the semiconductor wafer along a cutting line using a dicing blade, and cutting the semiconductor wafer into individual semiconductor chips;
And (c) dividing the adhesive layer into the semiconductor chips by expanding the wafer processing tape to obtain a plurality of chips with adhesive layers. It is characterized by.

  In the wafer processing tape of the present invention, the base film is composed of a plurality of resin layers laminated so that their film forming directions (MD) do not coincide with each other. Thereby, since the anisotropy of the expandability in the whole base film can be relieved, it is possible to obtain an isotropic excellent expandability. Therefore, it can be suitably used also in an expanding process for dividing an adhesive layer, which requires a large expanding speed and tensile force during expansion.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
1 and 2 show two examples of the wafer processing tape of the present invention. FIG. 1 is a cross-sectional view showing a dicing die bonding tape 10 in which a pressure-sensitive adhesive layer 12 and an adhesive layer 13 are laminated on a base film 11, and FIG. 2 is a pressure-sensitive adhesive layer on the base film 11. It is sectional drawing which shows the dicing tape 20 in which only 12 was formed. 1 and 2 show a state in which a semiconductor wafer W is bonded to a wafer processing tape.

Each layer may be cut (precut) into a predetermined shape in advance in accordance with the use process and apparatus. The tape for wafer processing of the present invention includes a form cut for each wafer and a form obtained by winding a plurality of long sheets formed in a roll shape.
Below, each layer is demonstrated in detail.

<Base film>
As shown in FIG. 3, the base film 11 has two resin layers 11 a and 11 b that are laminated so that the film forming direction (MD) is approximately 90 °. When a conventional base film is extruded, stress is applied in the film forming direction (MD), and stress in the direction (TD) perpendicular to this is suppressed. Whereas anisotropy occurs, the base film 11 of the present invention is laminated so that the upper layer 11a and the lower layer 11b form approximately 90 ° so that their film forming directions (MD) do not coincide with each other. Therefore, the expandable anisotropy of the entire base film can be reduced. Therefore, the dividing property of the adhesive layer in the MD and TD of the base film can be improved during expansion.

  The thicknesses of the upper layer 11a and the lower layer 11b are not particularly limited, and may be set in consideration of expandability, pickup responsiveness, strength, etc., but are preferably set in the range of 50 to 200 μm. Further, from the viewpoint of reducing the influence of strain stress generated anisotropically during the thickness extrusion of the upper layer 11a and the lower layer 11b, the upper layer 11a is preferably set smaller than the lower layer 11b.

(Upper layer of base film)
Although it does not specifically limit as the upper layer 11a of the base film 11, It is preferable to use the thermoplastic resin whose Vicat softening point prescribed | regulated by JISK7206 is 50 degreeC or more and less than 80 degreeC. When bonding the back surface of the wafer W to the adhesive layer 13, heating bonding at about 70 to 80 ° C. may be performed in order to heat soften the adhesive and improve adhesiveness. By using a thermoplastic resin having a Vicat softening point of less than 80 ° C. above, the upper layer 11a can be softened at the time of heat bonding, and the strain stress generated anisotropically during the molding of the film can be relaxed. Thereby, the anisotropy of extensibility can be further reduced. In addition, when the Vicat softening point is too low, the resin is excessively softened and fluidized at the time of the heat bonding, which is not preferable. Therefore, the lower limit of the Vicat softening point is suitably about 50 ° C.

As the thermoplastic resin, various conventionally known plastics, rubbers and the like can be used. Examples of commercially available resins include EMAA (Mitsui DuPont Nucrel N1560 (ethylene-methacrylic acid copolymer)), Ionomer (Mitsui DuPont High Milan 1705 (zinc ion-crosslinked ethylene-acrylic acid copolymer)). , EVA (Nippon Polychem Co., Ltd. FW3E (ethylene-vinyl acetate copolymer)), ULDPE (Nippon Polychem Co., Ltd. Kernel KF306T (ultra low density polyethylene)) and the like can be used.
As a pressure-sensitive adhesive layer 12 to be described later, particularly when a radiation-curable pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, it is preferable that the upper layer 11a of the base film is radiation transmissive.

(Lower layer of base film)
As the lower layer 11b of the base film 11, the same thermoplastic resin as that of the upper layer 11a can be used, but is not limited to this, and a known plastic, rubber, or the like may be used. As a pressure-sensitive adhesive layer 12 to be described later, particularly when a radiation-curable pressure-sensitive adhesive is used for the pressure-sensitive adhesive layer, it is preferable that the upper layer 11a of the base film is radiation transmissive. Examples of polymers that can be selected as such a substrate include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, ethylene-acrylic. Homopolymer or copolymer of α-olefin such as ethyl acid copolymer, ethylene-methyl acrylate copolymer, ethylene-acrylic acid copolymer, ionomer, or a mixture thereof, polyethylene terephthalate, polycarbonate, polymethyl methacrylate Engineering plastics such as polyurethane, thermoplastic elastomers such as polyurethane, styrene-ethylene-butene or pentene copolymers, polyamide-polyol copolymers, and mixtures thereof.

<Adhesive layer>
The pressure-sensitive adhesive layer 12 can be formed by applying a pressure-sensitive adhesive to the base film 11. There is no particular limitation on the pressure-sensitive adhesive layer constituting the wafer processing tape of the present invention, retainability that does not cause defects such as chip jumping with the adhesive layer during dicing, and easy peeling from the adhesive layer during pick-up It is sufficient if it has the characteristics to do. In order to improve the pickup property after dicing, the pressure-sensitive adhesive layer is preferably a radiation curable material, and is preferably a material that can be easily peeled off from the adhesive layer.

  For example, in the present invention, the compound (A) having a radiation curable carbon-carbon double bond having an iodine value of 0.5 to 20 in the molecule is selected from polyisocyanates, melamine / formaldehyde resins, and epoxy resins. It is preferable to contain a polymer obtained by subjecting at least one compound (B) to an addition reaction.

  The compound (A) that is one of the main components of the pressure-sensitive adhesive layer will be described. A preferable introduction amount of the radiation curable carbon-carbon double bond of the compound (A) is 0.5 to 20, more preferably 0.8 to 10 in terms of iodine value. If the iodine value is 0.5 or more, an effect of reducing the adhesive strength after irradiation can be obtained. If the iodine value is 20 or less, the fluidity of the adhesive after irradiation is sufficient and after stretching. Therefore, the problem that the image recognition of each element becomes difficult at the time of pick-up can be suppressed. Furthermore, the compound (A) itself is stable and easy to manufacture.

The compound (A) preferably has a glass transition point of −70 ° C. to 0 ° C., more preferably −66 ° C. to −28 ° C. When the glass transition point (hereinafter referred to as Tg) is −70 ° C. or higher, the heat resistance against heat associated with radiation irradiation is sufficient. A sufficient scattering prevention effect can be obtained.
The compound (A) may be produced by any method, and has, for example, a radiation curable carbon-carbon double bond such as an acrylic copolymer or a methacrylic copolymer, and a functional group. A compound obtained by reacting a compound having the functional group ((1)) with a compound having a functional group capable of reacting with the functional group ((2)) is used.

Among these, the compound ((1)) having the radiation curable carbon-carbon double bond and the functional group is a single compound having a radiation curable carbon-carbon double bond such as an acrylic acid alkyl ester or a methacrylic acid alkyl ester. It can be obtained by copolymerizing a monomer ((1) -1) and a monomer ((1) -2) having a functional group.
As a monomer ((1) -1), C6-C12 hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, decyl acrylate, or a single quantity of 5 or less carbon atoms The pentyl acrylate, n-butyl acrylate, isobutyl acrylate, ethyl acrylate, methyl acrylate, or methacrylates similar to these can be listed.

  Since a glass transition point becomes so low that a monomer with a large carbon number is used as a monomer ((1) -1), the thing of a desired glass transition point can be produced. In addition to the glass transition point, a monomer ((1) -1) may be blended with a low molecular compound having a carbon-carbon double bond such as vinyl acetate, styrene, acrylonitrile for the purpose of improving compatibility and various performances. ) In the range of 5% by mass or less of the total mass.

  Examples of the functional group of the monomer ((1) -2) include a carboxyl group, a hydroxyl group, an amino group, a cyclic acid anhydride group, an epoxy group, and an isocyanate group. The monomer ((1)- Specific examples of 2) include acrylic acid, methacrylic acid, cinnamic acid, itaconic acid, fumaric acid, phthalic acid, 2-hydroxyalkyl acrylates, 2-hydroxyalkyl methacrylates, glycol monoacrylates, glycol monomethacrylates. N-methylolacrylamide, N-methylolmethacrylamide, allyl alcohol, N-alkylaminoethyl acrylates, N-alkylaminoethyl methacrylates, acrylamides, methacrylamides, maleic anhydride, itaconic anhydride, fumaric anhydride, Phthalic anhydride, glycidyl acrylate And glycidyl methacrylate, allyl glycidyl ether, and those obtained by urethanizing a part of the isocyanate group of a polyisocyanate compound with a monomer having a hydroxyl group or a carboxyl group and a radiation curable carbon-carbon double bond. it can.

  In the compound (2), as the functional group used, when the functional group of the compound (1), that is, the monomer ((1) -2) is a carboxyl group or a cyclic acid anhydride group, a hydroxyl group, Examples include an epoxy group and an isocyanate group. In the case of a hydroxyl group, examples include a cyclic acid anhydride group and an isocyanate group. In the case of an amino group, examples include an epoxy group and an isocyanate group. In the case of an epoxy group, a carboxyl group, a cyclic acid anhydride group, an amino group and the like can be mentioned. Specific examples include those listed in the specific examples of the monomer ((1) -2) Can be listed.

By leaving an unreacted functional group in the reaction between the compound (1) and the compound (2), it is possible to produce those specified in the present invention with respect to characteristics such as acid value or hydroxyl value.
In the synthesis of the above compound (A), as the organic solvent when the reaction is carried out by solution polymerization, ketone, ester, alcohol, and aromatic solvents can be used, among which toluene, ethyl acetate , Isopropyl alcohol, benzene methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, etc., are generally good solvents for acrylic polymers and preferably have a boiling point of 60-120 ° C. The polymerization initiator is α, α′-azobisisobutyl. A radical generator such as an azobis type such as nitrile or an organic peroxide type such as benzoyl peroxide is usually used. At this time, a catalyst and a polymerization inhibitor can be used together as necessary, and the compound (A) having a desired molecular weight can be obtained by adjusting the polymerization temperature and the polymerization time. In terms of adjusting the molecular weight, it is preferable to use a mercaptan or carbon tetrachloride solvent. This reaction is not limited to solution polymerization, and other methods such as bulk polymerization and suspension polymerization may be used.

As described above, the compound (A) can be obtained. In the present invention, the molecular weight of the compound (A) is preferably about 300,000 to 1,000,000. If it is less than 300,000, the cohesive force due to radiation irradiation becomes small, and when the wafer is diced, the device is likely to be displaced, and image recognition may be difficult. In order to prevent the deviation of the element as much as possible, the molecular weight is preferably 400,000 or more. Further, if the molecular weight exceeds 1,000,000, there is a possibility of gelation at the time of synthesis and coating.
In addition, the molecular weight in this invention is a mass mean molecular weight of polystyrene conversion.

It is preferable that the compound (A) has an OH group having a hydroxyl value of 5 to 100 because the risk of pick-up mistakes can be further reduced by reducing the adhesive strength after irradiation. Moreover, it is preferable that a compound (A) has a COOH group used as the acid value of 0.5-30.
Here, if the hydroxyl value of the compound (A) is too low, the effect of reducing the adhesive strength after irradiation is not sufficient, and if it is too high, the fluidity of the adhesive after irradiation tends to be impaired. If the acid value is too low, the effect of improving the tape restoring property is not sufficient, and if it is too high, the fluidity of the pressure-sensitive adhesive tends to be impaired.

  Next, the compound (B) which is another main component of the pressure-sensitive adhesive layer will be described. The compound (B) is a compound selected from polyisocyanates, melamine / formaldehyde resins, and epoxy resins, and can be used alone or in combination of two or more. This compound (B) acts as a cross-linking agent, and the cross-linking structure formed as a result of reacting with the compound (A) or the base film causes the cohesive strength of the pressure-sensitive adhesive mainly composed of the compounds (A) and (B) to It can be improved after application.

  The polyisocyanates are not particularly limited, and examples thereof include 4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4′-diphenyl ether diisocyanate, 4,4 ′-[2,2-bis (4 -Phenoxyphenyl) propane] aromatic isocyanate such as diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethyl-hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4'-dicyclohexylmethane diisocyanate Lysine diisocyanate, lysine triisocyanate and the like. Specifically, Coronate L (trade name, manufactured by Nippon Polyurethane Co., Ltd.) or the like can be used.

Specific examples of the melamine / formaldehyde resin include Nicalac MX-45 (trade name, manufactured by Sanwa Chemical Co., Ltd.) and Mellan (trade name, manufactured by Hitachi Chemical Co., Ltd.).
As the epoxy resin, TETRAD-X (trade name, manufactured by Mitsubishi Chemical Corporation) or the like can be used.
In the present invention, it is particularly preferable to use polyisocyanates.

  The addition amount of (B) needs to be selected so as to be a ratio of 0.1 to 10 parts by weight, preferably 0.4 to 3 parts by weight with respect to 100 parts by weight of the compound (A). By selecting within this range, it is possible to obtain an appropriate cohesive force, and since the crosslinking reaction does not proceed abruptly, workability such as blending and application of the adhesive is improved.

Moreover, in this invention, it is preferable that the photoinitiator (C) is contained in the adhesive layer. There is no restriction | limiting in particular in the photoinitiator (C) in which an adhesive layer is contained, A conventionally well-known thing can be used. For example, benzophenones such as benzophenone, 4,4′-dimethylaminobenzophenone, 4,4′-diethylaminobenzophenone and 4,4′-dichlorobenzophenone, acetophenones such as acetophenone and diethoxyacetophenone, 2-ethylanthraquinone, t- Examples include anthraquinones such as butylanthraquinone, 2-chlorothioxanthone, benzoin ethyl ether, benzoin isopropyl ether, benzyl, 2,4,5-triarylimidazole dimer (lophine dimer), acridine compounds, and the like. These can be used alone or in combination of two or more.
As addition amount of (C), it is preferable to set it as 0.1-10 mass parts with respect to 100 mass parts of compounds (A), and it is more preferable to set it as 0.5-5 mass parts.

  Furthermore, the radiation-curable pressure-sensitive adhesive used in the present invention can be blended with a tackifier, a pressure-adjusting agent, a surfactant, or other modifiers as necessary. Moreover, you may add an inorganic compound filler suitably.

  The thickness of the pressure-sensitive adhesive layer is preferably at least 5 μm, more preferably 10 μm or more. The pressure-sensitive adhesive layer may have a structure in which a plurality of layers are laminated.

<Adhesive layer>
The adhesive layer 13 is peeled off from the adhesive layer and attached to the chip when the chip is picked up after the wafer is bonded and diced, and the adhesive for fixing the chip to the substrate or the lead frame. It is used as The adhesive layer is not particularly limited, but may be a film-like adhesive generally used for dicing die bonding tapes, such as an acrylic adhesive, epoxy resin / phenolic resin / acrylic resin. Of these, a blend-based adhesive is preferred. The thickness may be appropriately set, but is preferably about 5 to 100 μm.

  In the wafer processing tape 10 of the present invention, the adhesive layer is formed by laminating directly or indirectly a substrate film (hereinafter referred to as an adhesive film) directly or indirectly. Also good. It is preferable to apply a linear pressure of 0.01 to 10 N / m in a temperature range of 10 to 100 ° C. during laminating. In addition, the adhesive film is formed on the separator, and the separator may be peeled off after lamination, or it is used as a cover film for the adhesive tape for dicing die bonding as it is, and when bonding the wafer. It may be peeled off.

  Although an adhesive film may be laminated | stacked on the whole surface of an adhesive layer, you may laminate | stack the adhesive film cut | disconnected (pre-cut) in the shape according to the wafer previously bonded.

<Manufacturing method>
As a method for producing a base film composed of two resin layers according to this embodiment, a two-layer resin film is formed by a conventionally known extrusion molding method or the like, and the formed two-layer resin film is used as an adhesive or A dry laminating method in which layers are laminated via an adhesive can be employed. In the base film 11 manufactured by such a manufacturing method, an adhesive layer or an adhesive layer is further interposed between two resin layers of the base film, that is, between the upper layer 11a and the lower layer 11b. Become. As the pressure-sensitive adhesive, the same material as that of the above-mentioned pressure-sensitive adhesive layer 12 can be used, and as the adhesive, the same material as the material of the above-mentioned adhesive layer 13 can be used.

<Application>
The usage of the wafer processing tape of the present invention is not particularly limited as long as it is used in a method for manufacturing a semiconductor manufacturing apparatus including a step of dividing an adhesive layer by at least an expand. For example, it can be suitably used in the following manufacturing methods (A) to (C) of a semiconductor manufacturing apparatus.

Manufacturing method of semiconductor manufacturing apparatus (A):
(A) irradiating a laser beam to a part to be divided of the wafer W in advance to form a modified region by multiphoton absorption inside the wafer W;
(B) including a step of bonding the adhesive layer 13 of the wafer processing tape 10 to the back surface of the wafer W in any order;
(C) The wafer processing tape 10 is expanded to divide the wafer W and the adhesive layer 13 along the dividing line, thereby obtaining a plurality of semiconductor chips with an adhesive layer. .

Semiconductor device manufacturing method (B):
(A) a step of bonding the adhesive layer 13 of the wafer processing tape 10 to the back surface of the wafer W;
(B) irradiating a laser beam from the surface of the wafer W along a cutting line, and cutting into individual semiconductor chips;
(C) A method of manufacturing a semiconductor device, comprising: expanding the wafer processing tape 10 to divide the adhesive layer 13 for each semiconductor chip to obtain a plurality of chips with adhesive layers.

Manufacturing method of semiconductor manufacturing apparatus (C):
(A) a step of bonding the adhesive layer 13 of the wafer processing tape 10 to the back surface of the wafer W;
(B) cutting the wafer W along a cutting line using a dicing blade, and cutting into individual semiconductor chips;
(C) A method of manufacturing a semiconductor device, comprising: expanding the wafer processing tape 10 to divide the adhesive layer 13 for each semiconductor chip to obtain a plurality of chips with adhesive layers.

<How to use>
A method of using the tape when the dicing die bonding tape 10 of the present invention is applied to the above-described method (A) for manufacturing a semiconductor device will be described with reference to FIGS.
First, as shown in FIG. 4, a laser beam is irradiated to a portion to be divided of the semiconductor wafer W, and 30 modified regions by multiphoton absorption are formed inside the wafer.

Next, as shown in FIG. 5A, the adhesive layer 13 of the dicing die bonding tape 10 is bonded to the back surface of the wafer W, and the ring frame 40 is bonded to the outer periphery of the pressure-sensitive adhesive layer 12. Place the material film 11 side down on the stage 41 of the expanding device. In the figure, reference numeral 42 denotes a hollow cylindrical push-up member of the expanding device.
Prior to the step of irradiating the semiconductor wafer W with laser light, a bonding step with the wafer W may be performed.

  Next, as shown in FIG. 5B, in the state where the ring frame 40 is fixed, the push-up member 42 of the expanding device is raised, and the dicing die bonding tape 10 is expanded. As the expanding condition, the expanding speed is, for example, 10 to 200 mm / sec, and the expanding amount (push-up amount) is, for example, 5 to 30 mm. In this way, the dicing die bonding tape 10 is stretched in the circumferential direction, so that the semiconductor wafer W is divided in units of chips starting from the modified region. At this time, in the adhesive layer 13, expansion (deformation) due to the expansion is suppressed in the portion bonded to the back surface of the wafer W, and no breakage occurs. On the other hand, at the position between the chips, the tension due to the expansion of the tape is not present. Concentrate and break. Therefore, the adhesive layer 13 is also divided along with the wafer W.

  Thereafter, the pressure-sensitive adhesive layer 12 is subjected to radiation curing treatment or thermosetting treatment, and the chip C is pushed up from the lower surface side of the dicing die bonding tape 10 by a pin, and the chip C is adsorbed from the upper surface side of the tape 10 by an adsorption jig. Then pick up. Thereby, the semiconductor chip C with an adhesive can be obtained.

  In the present invention, from the viewpoint of improving the pickup responsiveness and preventing the peeling of the substrates at the time of pickup, a step of peeling the lower layer 11b of the substrate film 11 is performed prior to the pickup step. May be. For example, when the upper layer 11a and the lower layer 11b are laminated via the pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer is also cured simultaneously with the radiation curing process or the heat curing process of the pressure-sensitive adhesive layer 12, so In addition, the lower layer 11b can be peeled off. In addition, when the upper layer 11a and the lower layer 11b are laminated via an adhesive layer, for example, by using a relatively weak adhesive as the adhesive, the lower layer 11b can be peeled off. Before the step, the lower layer 11b can be peeled off.

  In the method of manufacturing a semiconductor device as described above, by using the base film 11 having two resin layers laminated so that the film forming directions (MD) of each other form approximately 90 °, Since the anisotropy of extensibility in the entire film 11 can be reduced, it becomes possible to obtain isotropic excellent extensibility, and during expansion, the adhesive layer is divided in the MD and TD of the base film. Can be made uniform.

  In the above-described embodiment, the structure in which the two resin layers are laminated so that the film forming direction (MD) is approximately 90 ° has been described, but the present invention is not limited to this, It is only necessary that the plurality of resin layers are laminated so that the film forming directions (MD) do not coincide with each other. For example, the resin forming directions (MD) of the three resin layers form 60 °. Thus, a laminated structure can be adopted. Even in such a configuration, since the film forming directions (MD) of each other do not match, the expandable anisotropy of the entire base film can be reduced, and the same effect as the above embodiment can be obtained. Can do.

It is sectional drawing which shows the state by which the semiconductor wafer was bonded by the tape for wafer processing concerning embodiment of this invention. It is sectional drawing which shows the state by which the semiconductor wafer was bonded to the tape for wafer processing concerning other embodiment of this invention. It is a disassembled perspective view which shows the structure of the base film of this invention. It is sectional drawing which shows a mode that the modification | reformation area | region was formed in the semiconductor wafer by laser processing. (A) is sectional drawing which shows the state in which the tape for wafer processing was mounted in the expand apparatus. (B) is sectional drawing which shows the tape for wafer processing after expansion, and a semiconductor wafer.

Explanation of symbols

10: Dicing die bonding tape 11: Base film 11a: Upper layer 11b: Lower layer 12: Adhesive layer 13: Adhesive layer 20: Dicing tape 40: Ring frame 41: Stage 42: Push-up member

Claims (10)

An expandable wafer processing tape used when dividing an adhesive layer along a chip by expanding,
A base film composed of a plurality of resin layers laminated so that their film forming directions (MD) do not coincide with each other;
A tape for wafer processing, comprising: an adhesive layer provided on the base film.   2. The wafer processing tape according to claim 1, wherein the base film is a two-layered resin layer that is laminated so that a film forming direction (MD) thereof is approximately 90 °.   The wafer processing tape according to claim 2, wherein each of the two resin layers has a thickness of 50 to 200 μm.   The upper layer in contact with the pressure-sensitive adhesive layer out of the two resin layers is made of a thermoplastic resin having a Vicat softening point defined by JIS K7206 of 50 ° C or higher and lower than 80 ° C. The tape for wafer processing according to claim 3.   5. The wafer processing tape according to claim 2, further comprising an adhesive layer between the two resin layers. 6.   5. The wafer processing tape according to claim 2, further comprising an adhesive layer between the two resin layers. 6.   The tape for wafer processing according to any one of claims 1 to 6, further comprising an adhesive layer on the pressure-sensitive adhesive layer. The wafer processing tape is
(A) irradiating a laser beam to a part to be divided of a semiconductor wafer in advance, and forming a modified region by multiphoton absorption inside the wafer;
(B) including a step of laminating the adhesive layer of the wafer processing tape on the back surface of the semiconductor wafer in a random order;
(C) expanding the wafer processing tape to divide the semiconductor wafer and the adhesive layer along a dividing line to obtain a plurality of semiconductor chips with an adhesive layer. The tape for wafer processing according to any one of claims 1 to 7, wherein the tape is used in a method. The wafer processing tape is
(A) bonding the adhesive layer of the wafer processing tape to the back surface of the semiconductor wafer;
(B) irradiating a laser beam along a dividing line from the surface of the semiconductor wafer to divide into individual semiconductor chips;
And (c) dividing the adhesive layer into the semiconductor chips by expanding the wafer processing tape to obtain a plurality of chips with adhesive layers. The wafer processing tape according to any one of claims 1 to 7, wherein the tape is used for processing a wafer. The wafer processing tape is
(A) bonding the adhesive layer of the wafer processing tape to the back surface of the semiconductor wafer;
(B) cutting the semiconductor wafer along a cutting line using a dicing blade, and cutting the semiconductor wafer into individual semiconductor chips;
And (c) dividing the adhesive layer into the semiconductor chips by expanding the wafer processing tape to obtain a plurality of chips with adhesive layers. The tape for wafer processing according to any one of claims 1 to 7, wherein:

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