JP2019179841A - Semiconductor-processing sheet - Google Patents

Abstract

To provide a semiconductor-processing sheet which is hardly chipped in dicing, and shows a superior heat resistance and excellent flexibility.SOLUTION: A semiconductor-processing sheet 1 comprises: a base material 10; a mid layer 20; and a sticker layer 30 formed from an activation energy ray-curable sticker. As to the semiconductor-processing sheet 1, the product of an expansion coefficient(%) of a material of the base material 10 when the material is heated and a thickness (μm) of the base material 10 is -20 to 120%μm. The mid layer 20 has a storage elastic modulus of 0.05-200 MPa. Supposing that an adhesive force to a silicon wafer after curing of the sticker layer 20 by exposure to activation energy rays is F1, and an adhesive force to the silicon wafer which has suffered one-hour 120°C heating subsequent to the curing of the sticker layer 20 by exposure to activation energy rays is F2, an adhesive force change rate calculated from adhesive force change rate=(F2/F1)×100 is 2-200%.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a semiconductor processing suitably used for a semiconductor device manufacturing method including a step of dicing a semiconductor wafer to obtain a plurality of semiconductor chips, a step of heating the semiconductor chips, and a step of individually picking up the semiconductor chips. It is related to the sheet.

  In general, a semiconductor device manufacturing method includes a dicing step of obtaining a plurality of semiconductor chips by dicing a semiconductor wafer on a semiconductor processing sheet, and individually obtaining the obtained semiconductor chips from the semiconductor processing sheet. (Pickup) pick-up process.

  In the dicing step, chipping may occur on the cut surface of the semiconductor chip during dicing. When such chipping occurs, there is a problem that the strength of the semiconductor chip is reduced or the semiconductor chip does not function properly. For this reason, the semiconductor processing sheet is required to be less susceptible to chipping during dicing.

  Moreover, in the said pick-up process, in order to make the pick-up of a semiconductor chip easy, a semiconductor chip may be pushed up individually from the surface opposite to the surface where the semiconductor chip was laminated | stacked in the sheet | seat for semiconductor processing. For this reason, the sheet | seat for semiconductor processing is calculated | required by the softness | flexibility which can perform such pushing up favorably.

  Furthermore, in the above pick-up process, an expansion process for expanding the semiconductor processing sheet and separating the semiconductor chips from each other is performed in order to suppress collision between the semiconductor chips during pick-up and to facilitate pick-up. Sometimes it is done. In order to perform the expansion well, the semiconductor processing sheet is required to have excellent flexibility.

  In recent years, heating is performed in a state where individual semiconductor chips are stacked on a semiconductor processing sheet. For example, processing such as vapor deposition, sputtering, baking for dehumidification is performed on a semiconductor chip on a semiconductor processing sheet, or when the semiconductor chip is used in a high temperature environment, A heating test may be performed to confirm the reliability. When performing such heating, the semiconductor processing sheet to be used is required to have heat resistance such that the deformation due to heating hardly occurs and the adhesive force to the semiconductor chip does not increase excessively by heating.

  As an example of a semiconductor processing sheet having heat resistance, Patent Document 1 discloses that the temperature is raised from room temperature to 200 ° C. at a rate of temperature rise of 2 ° C./min on at least one side of a substrate having a glass transition temperature of 70 ° C. or higher. The heat-resistant dicing tape or sheet is provided with a pressure-sensitive adhesive layer having a thermal weight reduction rate of less than 2%, and the pressure-sensitive adhesive layer is composed of an energy ray-curable pressure-sensitive adhesive having a predetermined composition. In addition, a heat-resistant dicing tape or sheet is disclosed in which the adhesive strength after the treatment including heating exhibits a predetermined value.

  Further, as another example of a semiconductor processing sheet having heat resistance, Patent Document 2 discloses a base material having a predetermined heat shrinkage rate, and an adhesive layer provided on the base material and having a predetermined composition. A heat-resistant pressure-sensitive adhesive sheet is disclosed, and Patent Document 3 discloses a base material having a predetermined thermal shrinkage rate and a linear expansion coefficient, and a pressure-sensitive adhesive layer provided on the base material and having a predetermined composition. A heat-resistant pressure-sensitive adhesive sheet is disclosed.

Japanese Patent No. 4781185 International Publication No. 2015/1743481 International Publication No. 2014/199993

  However, although the semiconductor processing sheets disclosed in Patent Documents 1 to 3 have predetermined heat resistance, they cannot exhibit sufficient flexibility and cannot perform good pickup. Thus, in the conventional sheet for semiconductor processing, it is difficult to achieve both the above-described flexibility and heat resistance. When one of the characteristics is prioritized, the other characteristic is easily impaired.

  The present invention has been made in view of such a situation, and an object of the present invention is to provide a semiconductor processing sheet that hardly causes chipping during dicing and exhibits excellent heat resistance and flexibility.

In order to achieve the above object, first, the present invention includes a base material, an intermediate layer laminated on one side of the base material, and a laminated surface on the opposite side of the intermediate layer from the base material. A semiconductor processing sheet comprising an adhesive layer, wherein the material of the base material is 23 ° C. to 120 ° C. at a temperature rising temperature of 10 ° C./min under a load of 0.2 g using a thermomechanical analyzer. The product of the coefficient of expansion (%) when heated and the thickness (μm) of the substrate is −20% · μm or more and 120% · μm or less, and the storage elastic modulus of the intermediate layer at 23 ° C. Is about 0.05 MPa or more and 200 MPa or less, and the adhesive layer is composed of an active energy ray-curable adhesive, and the semiconductor is a laminate obtained by attaching the semiconductor processing sheet to a silicon wafer. Irradiate active energy rays to the processing sheet After the adhesive layer is cured, the adhesive strength of the semiconductor processing sheet to the silicon wafer is F1, and the laminate formed by attaching the semiconductor processing sheet to the silicon wafer is applied to the semiconductor processing sheet. The adhesive layer is cured by irradiating active energy rays, and then the laminate is heated at 120 ° C. for 1 hour, when the adhesive force of the semiconductor processing sheet to the silicon wafer is F2. The following formula (1)
Adhesive force change rate = (F2 / F1) × 100 (1)
The rate of change in adhesive force calculated from the above is 2% or more and 200% or less, which provides a semiconductor processing sheet (Invention 1).

  The semiconductor processing sheet according to the invention (Invention 1) includes an intermediate layer having the storage elastic modulus described above, and a base material in which the product of the expansion coefficient and the thickness is in the above-described range. Suppresses the vibration of the semiconductor processing sheet to prevent chipping, suppresses deformation when the semiconductor processing sheet is heated, and exhibits excellent heat resistance. The sheet exhibits excellent flexibility and is easy to expand. In addition, the semiconductor processing sheet is provided with an adhesive layer that satisfies the adhesive force change rate as described above, so that the adhesive force is hardly changed by heating, and this also exhibits excellent heat resistance. it can.

  In the said invention (invention 1), it is preferable that the thickness of the said intermediate | middle layer is 20 micrometers or more and 100 micrometers or less (invention 2).

  In the said invention (invention 1 and 2), it is preferable that the thickness of the said adhesive layer is thinner than the thickness of the said intermediate | middle layer (invention 3).

  In the said invention (invention 3), it is preferable that the thickness of the said adhesive layer is 5 micrometers or more and 30 micrometers or less (invention 4).

  In the said invention (invention 1-4), it is preferable that the storage elastic modulus in 23 degreeC of the said adhesive layer is smaller than the storage elastic modulus in 23 degreeC of the said intermediate | middle layer (invention 5).

  In the said invention (invention 5), it is preferable that the storage elastic modulus in 23 degreeC of the said adhesive layer is 0.01 Mpa or more and 10 Mpa or less (invention 6).

  In the said invention (invention 1-6), it is preferable that the thickness of the said base material is 10 micrometers or more and 200 micrometers or less (invention 7).

  In the said invention (invention 1-7), it is preferable that the tensile elasticity modulus in 23 degreeC of the said base material is 100 Mpa or more and 1000 Mpa or less (invention 8).

  In the said invention (invention 1-8), it is preferable that the said intermediate | middle layer is comprised from the adhesive which does not have active energy ray curability (invention 9).

  The semiconductor processing sheet according to the present invention is less susceptible to chipping during dicing, and can exhibit excellent heat resistance and flexibility.

It is sectional drawing of the sheet | seat for semiconductor processing which concerns on this embodiment.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 shows a cross-sectional view of a semiconductor processing sheet 1 according to this embodiment. The semiconductor processing sheet 1 according to the present embodiment is laminated on the base 10, the intermediate layer 20 laminated on one side of the base 10, and the surface of the intermediate layer 20 opposite to the base 10. The adhesive layer 30 and the release sheet 40 laminated on the surface of the adhesive layer 30 opposite to the intermediate layer 20 are provided. In addition, in the sheet | seat 1 for semiconductor processing which concerns on this embodiment, the peeling sheet 40 may be abbreviate | omitted.

  In the semiconductor processing sheet 1 according to the present embodiment, the material of the base material 10 was heated from 23 ° C. to 120 ° C. at a temperature rising temperature of 10 ° C./min under a load of 0.2 g using a thermomechanical analyzer. The product of the expansion coefficient (%) and the thickness (μm) of the substrate 10 is −20% · μm or more and 120% · μm or less. In addition, the detail of the measuring method of the said expansion coefficient is as describing in the test example mentioned later.

  Moreover, in the sheet | seat 1 for semiconductor processing which concerns on this embodiment, the storage elastic modulus in 23 degreeC of the intermediate | middle layer 20 is 0.05 MPa or more and 200 MPa or less. In addition, the detail of the measuring method of the storage elastic modulus in this specification is as having described in the test example mentioned later.

  In the semiconductor processing sheet 1 according to the present embodiment, the product of the expansion coefficient and the thickness of the base material 10 is in the above-described range, and the storage elastic modulus at 23 ° C. of the intermediate layer 20 is in the above-described range. While suppressing the vibration of the semiconductor processing sheet 1 during processing, the semiconductor processing sheet 1 has excellent flexibility. By suppressing the vibration, chipping of the formed semiconductor chip can be suppressed when the semiconductor processing sheet 1 is used for dicing a semiconductor member. Moreover, it becomes possible to expand the sheet | seat 1 for semiconductor processing favorably by having the outstanding softness | flexibility. Furthermore, the semiconductor processing sheet 1 includes the base material 10 and the intermediate layer 20 having the physical properties described above, thereby suppressing deformation during heating and exhibiting excellent heat resistance.

  In addition, as said heating conditions, it is preferable that heating temperature is 80 degreeC or more, for example, and it is especially preferable that it is 100 degreeC or more. Further, the heating temperature is preferably 300 ° C. or lower, and particularly preferably 270 ° C. or lower. As heating time, it is preferable that it is 10 minutes or more, for example, and it is especially preferable that it is 30 minutes or more. The heating time is preferably 25 hours or less, and particularly preferably 10 hours or less.

  When the product of the expansion coefficient and the thickness of the base material 10 does not fall within the above-described range, at least one of problems such as generation of chipping, reduction in flexibility, and generation of deformation during heating occurs. In particular, when the product is less than −20% · μm, among these problems, the flexibility is lowered, and good expansion cannot be performed. Further, when the product exceeds 120% · μm, among the above-described problems, deformation during heating is likely to occur. From these viewpoints, the product is preferably 0% · μm or more, and particularly preferably 40% · μm or more. Further, the product is preferably 110% · μm or less, particularly preferably 100% · μm or less.

  Further, if the storage elastic modulus at 23 ° C. of the intermediate layer 20 is less than 0.05 MPa, vibration of the semiconductor processing sheet 1 during processing cannot be sufficiently suppressed, and chipping occurs during dicing. It will be a thing. On the other hand, when the storage elastic modulus of the intermediate layer 20 at 23 ° C. exceeds 200 MPa, the flexibility of the semiconductor processing sheet 1 is lowered, and good expansion cannot be performed. From such a viewpoint, the storage elastic modulus at 23 ° C. of the intermediate layer 20 is preferably 0.1 MPa or more, and particularly preferably 0.2 MPa or more. The storage elastic modulus is preferably 10 MPa or less, and particularly preferably 1 MPa or less.

  In the semiconductor processing sheet 1 according to this embodiment, the pressure-sensitive adhesive layer 30 is composed of an active energy ray-curable pressure-sensitive adhesive. Thereby, by irradiating an active energy ray, the adhesive layer 30 can be hardened and the adhesive force of the sheet | seat 1 for semiconductor processing can be reduced. Therefore, in the semiconductor processing sheet 1 according to the present embodiment, the semiconductor member after processing can be easily separated by irradiating active energy rays.

Moreover, as for the semiconductor processing sheet 1 which concerns on this embodiment, the change rate of the adhesive force before and behind a heating becomes a range described below. That is, about the laminated body formed by sticking the semiconductor processing sheet 1 to the silicon wafer, the semiconductor processing sheet 1 after the active energy ray is irradiated to the semiconductor processing sheet 1 and the adhesive layer is cured. F1 is the adhesive force to the silicon wafer,
About the laminated body formed by attaching the semiconductor processing sheet 1 to a silicon wafer, the semiconductor processing sheet 1 is irradiated with an active energy ray to cure the adhesive layer, and then the laminated body is heated at 120 ° C. When the adhesive force of the semiconductor processing sheet to the silicon wafer after heating for 1 hour is F2,
Following formula (1)
Adhesive force change rate = (F2 / F1) × 100 (1)
The adhesive force change rate calculated from the above is 2% or more and 200% or less. In addition, the detail of the measuring method of the adhesive force F1 mentioned above and the adhesive force F2 is as describing in the test example mentioned later.

  In the semiconductor processing sheet 1 according to the present embodiment, the adhesive force change rate described above is in the above range, so that even when the semiconductor processing sheet 1 is subjected to a heating process, the adhesive power is increased before and after the process. It will be difficult to change. Thereby, it is suppressed that the adhesive force with respect to the semiconductor member of the sheet | seat 1 for semiconductor processing raises excessively by heating, and it becomes possible to isolate | separate the processed semiconductor member from the sheet | seat 1 for semiconductor processing easily by this. Become. Also from this point, the semiconductor processing sheet 1 according to the present embodiment can exhibit excellent heat resistance.

  When the adhesive force change rate described above exceeds 200%, the adhesive force of the semiconductor processing sheet 1 is excessively increased by heating, and it is difficult to separate the processed semiconductor member from the semiconductor processing sheet 1. During the separation, an excessive load is applied to the semiconductor member, and the semiconductor member is damaged. From this viewpoint, the above-described adhesive force change rate is preferably 150% or less, and particularly preferably 120% or less. Moreover, when the adhesive force change rate mentioned above is less than 2%, the adhesive force of the semiconductor processing sheet 1 is excessively reduced by heating, and the semiconductor member to be attached is placed on the semiconductor processing sheet 1. Will not be properly retained. From this viewpoint, the above-described adhesive force change rate is preferably 50% or more, and particularly preferably 75% or more.

  As described above, the semiconductor processing sheet 1 according to the present embodiment includes the base material 10, the intermediate layer 20, and the pressure-sensitive adhesive layer 30 that can achieve the physical properties described above. In combination, it is possible to suppress the occurrence of chipping during dicing, to exhibit excellent flexibility, and to exhibit excellent heat resistance.

1. Configuration of Semiconductor Processing Sheet (1) Base Material The base material 10 in the present embodiment is not particularly limited as long as the physical properties described above regarding the expansion coefficient and thickness are satisfied. As the base material 10, those capable of achieving the performance usually required as a base material for a semiconductor processing sheet are preferable. From such a viewpoint, the base material 10 is a film mainly composed of a resin-based material (hereinafter “resin”). It is preferable to be comprised of a “film”.

  Specific examples of the resin film include polyethylene films such as low density polyethylene (LDPE) film, linear low density polyethylene (LLDPE) film, and high density polyethylene (HDPE) film, polypropylene film, polybutene film, polybutadiene film, polymethyl. Polyolefin films such as pentene film, ethylene-norbornene copolymer film, norbornene resin film; soft polybutylene terephthalate film; ethylene-vinyl acetate copolymer film, ethylene- (meth) acrylic acid copolymer film, ethylene- ( Ethylene-based copolymer films such as (meth) acrylic acid ester copolymer films; Polyvinyl chloride-based films such as polyvinyl chloride films and vinyl chloride copolymer films; Lenfilm; and fluorine resin film. Further, modified films such as these crosslinked films and ionomer films are also used. The substrate 10 may be a film made of one of these, or may be a laminated film in which two or more of these are combined. Among these, a polypropylene film or a soft polybutylene terephthalate film is preferable from the viewpoint of exhibiting excellent flexibility. In this specification, (meth) acrylic acid ester means both acrylic acid ester and methacrylic acid ester. The same applies to other similar terms.

  One surface of the substrate 10 may be subjected to a surface treatment such as an oxidation method or a concavo-convex method or a primer treatment for the purpose of improving the adhesion with the intermediate layer 20. Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet), flame treatment, hot air treatment, ozone, ultraviolet irradiation treatment, and the like. Examples include a thermal spraying method.

  The base material 10 may contain various additives such as a colorant, a flame retardant, a plasticizer, an antistatic agent, a lubricant, and a filler in the resin film.

  Moreover, it is preferable that the base material 10 has the permeability | transmittance with respect to an active energy ray from a viewpoint of hardening the adhesive layer 30 efficiently by irradiation of an active energy ray.

  In the base material 10 in the present embodiment, the above-described expansion coefficient, that is, the material constituting the base material 10 is 23 ° C. at a temperature rising temperature of 10 ° C./min under a load of 0.2 g using a thermomechanical analyzer. It is preferable that the expansion coefficient when heated from 1 to 120 ° C. is −10% or more. Further, the expansion coefficient is preferably 2% or less. When the expansion coefficient is in the above-described range, the product of the expansion coefficient and the thickness of the base material 10 can be easily adjusted to the above-described range, and expansion of the base material 10 due to heating hardly occurs. Deformation of the semiconductor processing sheet 1 is effectively suppressed, and processing with heating can be performed better.

  In the semiconductor processing sheet 1 according to this embodiment, it is preferable that the tensile elastic modulus at 23 ° C. of the base material 10 is 100 MPa or more. Moreover, it is preferable that the said tensile elasticity modulus is 1000 Mpa or less. When the tensile elastic modulus is 100 MPa or more, the semiconductor processing sheet 1 does not easily vibrate during processing, and when the semiconductor member is diced using the semiconductor processing sheet 1, chipping during dicing is performed. Can be effectively suppressed. Moreover, because the tensile elastic modulus is 1000 MPa or less, the semiconductor processing sheet 1 has better flexibility, and the semiconductor processing sheet 1 is easily expanded. In addition, the measuring method of the said tensile elasticity modulus is as having described in the column of the Example mentioned later.

  The substrate 10 is preferably made of a material having a melting point of 130 ° C. or higher, particularly preferably made of a material having a melting point of 150 ° C. or higher, and more preferably made of a material having a melting point of 180 ° C. or higher. Since the melting point of the material constituting the base material 10 is 130 ° C. or higher, even if the base material 10 is heated in the process of heating the semiconductor processing sheet 1, it melts and adheres to a heating table or the like. Is suppressed. In addition, although there is no restriction | limiting in particular about the upper limit of melting | fusing point of the material which comprises the base material 10, Usually, it is preferable that the base material 10 consists of material whose melting | fusing point is 500 degrees C or less, and especially consists of material whose melting | fusing point is 400 degrees C or less. It is preferable that the material is made of a material having a melting point of 300 ° C. or lower.

  The thickness of the substrate 10 is preferably 10 μm or more, particularly preferably 25 μm or more, and more preferably 30 μm or more. The thickness is preferably 200 μm or less, particularly preferably 150 μm or less, and more preferably 100 μm or less. It becomes easy to adjust the product of the said expansion coefficient and the thickness of the base material 10 to the range mentioned above because the thickness of the base material 10 is the said range. In particular, when the thickness is 10 μm or more, the semiconductor processing sheet 1 is less likely to vibrate during processing, and when the semiconductor member is diced using the semiconductor processing sheet 1, Chipping can be effectively suppressed. Moreover, the said thickness is 200 micrometers or less, the softness | flexibility of the sheet | seat 1 for semiconductor processing becomes more excellent, and it becomes what expands easily.

(2) Intermediate Layer The intermediate layer 20 in the present embodiment is not particularly limited as long as the storage elastic modulus at 23 ° C. is in the above-described range. For example, the intermediate layer 20 may be the one described above as the resin film constituting the substrate 10. However, from the viewpoint of easily adjusting the storage elastic modulus at 23 ° C. to the above-described range, the intermediate layer 20 is preferably made of a pressure-sensitive adhesive.

  The pressure-sensitive adhesive constituting the intermediate layer 20 may be a pressure-sensitive adhesive that does not have active energy ray curability (hereinafter may be referred to as “active energy ray non-curable pressure-sensitive adhesive”). From the viewpoint that the storage elastic modulus at 23 ° C. can be easily adjusted to the above-described range, the intermediate layer 20 may be a pressure-sensitive adhesive (hereinafter sometimes referred to as “active energy ray-curable pressure-sensitive adhesive”). It is preferably composed of an active energy ray non-curable adhesive.

  Further, when the intermediate layer 20 is composed of an active energy ray-curable adhesive, the adhesive may be one that has not been irradiated with active energy rays and has not been cured, It is preferable that it is hardened | cured by irradiation of an active energy ray. That is, the intermediate layer 20 is irradiated with active energy rays at the time of manufacturing the semiconductor processing sheet 1. As a result, in the obtained semiconductor processing sheet 1, the active energy ray curable adhesive constituting the intermediate layer 20. It is preferred that the agent is already cured. Thereby, before and after irradiating the semiconductor processing sheet 1 with active energy rays, the physical properties and properties of the intermediate layer 20 are easily maintained, and the semiconductor processing sheet 1 according to the present embodiment stabilizes the effects described above. It will be easy to demonstrate.

  Examples of the active energy ray non-curable pressure sensitive adhesive include acrylic pressure sensitive adhesive, rubber pressure sensitive adhesive, silicone pressure sensitive adhesive, urethane pressure sensitive adhesive, polyester pressure sensitive adhesive, and polyvinyl ether pressure sensitive adhesive. it can. Among these, an acrylic pressure-sensitive adhesive is preferable from the viewpoint that the storage elastic modulus of the intermediate layer 20 at 23 ° C. can be easily adjusted to the above-described range.

  When the intermediate layer 20 is made of the acrylic pressure-sensitive adhesive, the intermediate layer 20 is preferably formed from a pressure-sensitive adhesive composition containing an acrylic copolymer. The acrylic copolymer preferably contains a structural unit derived from a (meth) acrylic acid ester monomer or a derivative thereof and a structural unit derived from a functional group-containing monomer.

  As the (meth) acrylic acid ester monomer constituting the acrylic copolymer, a (meth) acrylic acid alkyl ester monomer having an alkyl group having 1 to 20 carbon atoms is preferably used.

  In particular, (meth) acrylic acid ester monomers include (meth) acrylic acid alkyl ester monomers having 1 to 18 carbon atoms in the alkyl group, such as methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) Propyl acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and the like are preferably used. These may be used individually by 1 type and may be used in combination of 2 or more type. Among these, it is preferable to use at least one of 2-ethylhexyl acrylate and methyl methacrylate.

  The acrylic copolymer preferably contains a structural unit derived from a (meth) acrylic acid ester monomer or derivative thereof in a proportion of 50% by mass or more, particularly preferably 60% by mass or more, and more preferably 70% by mass or more. To do. The acrylic copolymer preferably contains 99% by mass or less, particularly preferably 95% by mass or less, and more preferably 90% by mass or less of a structural unit derived from a (meth) acrylic acid ester monomer or a derivative thereof. Contains.

  The functional group-containing monomer as a constituent unit of the acrylic copolymer is a monomer having a polymerizable double bond and a functional group such as a hydroxy group, a carboxy group, an amino group, a substituted amino group, and an epoxy group in the molecule. It is preferable that

  Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, ( Examples thereof include 3-hydroxybutyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate, and these are used alone or in combination of two or more. Among these, it is preferable to use 2-hydroxyethyl acrylate.

  Examples of the carboxy group-containing monomer include ethylenically unsaturated carboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, itaconic acid, and citraconic acid. These may be used alone or in combination of two or more. Among these, it is preferable to use acrylic acid.

  Examples of the amino group-containing monomer or substituted amino group-containing monomer include aminoethyl (meth) acrylate and n-butylaminoethyl (meth) acrylate. These may be used alone or in combination of two or more.

  The acrylic copolymer preferably contains a constituent unit derived from the functional group-containing monomer in a proportion of 1% by mass or more, particularly preferably 5% by mass or more, and more preferably 10% by mass or more. The acrylic copolymer contains a constituent unit derived from the functional group-containing monomer, preferably in a proportion of 35% by mass or less, particularly preferably 30% by mass or less, and further preferably 25% by mass or less.

  The acrylic copolymer may contain other monomers other than the above-mentioned (meth) acrylic acid alkyl ester monomer and functional group-containing monomer as monomer units constituting the polymer.

  Examples of the other monomers include alkoxyalkyl group-containing (meth) acrylic such as methoxymethyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxymethyl (meth) acrylate, and ethoxyethyl (meth) acrylate. Acid ester; cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, adamantyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclo (meth) acrylate (Meth) acrylic acid ester having an aliphatic ring such as pentenyloxyethyl; (meth) acrylic acid ester having an aromatic ring such as phenyl (meth) acrylate; non-crosslinkable acrylamide such as acrylamide and methacrylamide; (Meth) acrylic acid N, N-dimethyl Aminoethyl, (meth) acrylic acid N, N-having non-crosslinking tertiary amino groups of dimethylamino propyl (meth) acrylate; vinyl acetate; etc. styrene. These may be used alone or in combination of two or more.

  The polymerization mode of the acrylic copolymer may be a random copolymer or a block copolymer. Moreover, it does not specifically limit regarding the polymerization method, It can superpose | polymerize by a general polymerization method.

  The weight average molecular weight (Mw) of the acrylic copolymer is preferably 10,000 or more, particularly preferably 150,000 or more, and more preferably 200,000 or more. The weight average molecular weight (Mw) is preferably 150 or less, particularly preferably 120 or less, and further preferably 100 or less. In addition, the weight average molecular weight (Mw) in this specification is the value of standard polystyrene conversion measured by the gel permeation chromatography method (GPC method).

  The pressure-sensitive adhesive composition for forming the intermediate layer 20 preferably contains a crosslinking agent together with the above-mentioned acrylic copolymer. When the pressure-sensitive adhesive composition contains a cross-linking agent, the acrylic copolymer is cross-linked in the intermediate layer 20 and a good three-dimensional network structure can be formed. Thereby, it becomes easy to adjust the storage elastic modulus of the intermediate layer 20 at 23 ° C. to the above-described range.

  Examples of crosslinking agents include isocyanate compounds, epoxy compounds, amine compounds, melamine compounds, aziridine compounds, hydrazine compounds, aldehyde compounds, oxazoline compounds, metal alkoxide compounds, metal chelate compounds, metal salts, ammonium salts, reactive phenol resins, etc. Can be mentioned.

  The isocyanate-based crosslinking agent preferably includes at least a polyisocyanate compound. Examples of the polyisocyanate compound include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate and hydrogenated diphenylmethane diisocyanate, and the like. , And their biuret bodies, isocyanurate bodies, and adduct bodies that are a reaction product with low molecular active hydrogen-containing compounds such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil, and the like. Among these, trimethylolpropane-modified aromatic polyisocyanate, particularly trimethylolpropane-modified tolylene diisocyanate is preferable.

  The content of the crosslinking agent in the above-mentioned pressure-sensitive adhesive composition is preferably 0.3 parts by mass or more, particularly preferably 1 part by mass or more, with respect to 100 parts by mass of the acrylic copolymer. Furthermore, it is preferable that it is 3 mass parts or more. Further, the content is preferably 18 parts by mass or less, particularly preferably 15 parts by mass or less, and more preferably 12 parts by mass or less with respect to 100 parts by mass of the acrylic copolymer. preferable.

  As long as the above-described pressure-sensitive adhesive composition does not impair the above-described effects of the semiconductor processing sheet 1 according to the present embodiment, desired additives such as a silane coupling agent, an antistatic agent, a tackifier, an antioxidant, Light stabilizers, softeners, fillers, refractive index adjusters, and the like can be added. In addition, the below-mentioned polymerization solvent and dilution solvent shall not be contained in the additive which comprises an adhesive composition.

  The above-mentioned pressure-sensitive adhesive composition can be produced by producing an acrylic polymer and mixing the obtained acrylic polymer, and, if desired, a crosslinking agent and an additive.

  The acrylic polymer can be produced by polymerizing a mixture of monomers constituting the polymer by an ordinary radical polymerization method. The polymerization is preferably carried out by a solution polymerization method using a polymerization initiator if desired. Examples of the polymerization solvent include ethyl acetate, n-butyl acetate, isobutyl acetate, toluene, acetone, hexane, methyl ethyl ketone, and the like. Two or more kinds may be used in combination.

  Examples of the polymerization initiator include azo compounds and organic peroxides, and two or more kinds may be used in combination. Examples of the azo compound include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane 1-carbonitrile), 2 , 2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2,4-dimethyl-4-methoxyvaleronitrile), dimethyl 2,2′-azobis (2-methylpropionate) 4,4′-azobis (4-cyanovaleric acid), 2,2′-azobis (2-hydroxymethylpropionitrile), 2,2′-azobis [2- (2-imidazolin-2-yl) Propane] and the like.

  Examples of organic peroxides include benzoyl peroxide, t-butyl perbenzoate, cumene hydroperoxide, diisopropyl peroxydicarbonate, di-n-propyl peroxydicarbonate, and di (2-ethoxyethyl) peroxy. Examples include dicarbonate, t-butyl peroxyneodecanoate, t-butyl peroxybivalate, (3,5,5-trimethylhexanoyl) peroxide, dipropionyl peroxide, diacetyl peroxide and the like.

  In addition, in the said superposition | polymerization process, the weight average molecular weight of the polymer obtained can be adjusted by mix | blending chain transfer agents, such as 2-mercaptoethanol.

  Once the acrylic polymer is obtained, if necessary, a crosslinking agent, other additives, and a diluting solvent are added to the acrylic polymer solution and mixed thoroughly to prepare a coating solution for the pressure-sensitive adhesive composition. Obtainable. When any of the above components is used in a solid state or when precipitation occurs when mixed with other components in an undiluted state, the component is used alone as a dilution solvent. It may be dissolved or diluted and then mixed with other components.

  Examples of the dilution solvent include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane, aromatic hydrocarbons such as toluene and xylene, halogenated hydrocarbons such as methylene chloride and ethylene chloride, methanol, ethanol, propanol, butanol, Alcohols such as 1-methoxy-2-propanol, ketones such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, and cyclohexanone, esters such as ethyl acetate and butyl acetate, and cellosolve solvents such as ethyl cellosolve are used.

  The concentration / viscosity of the coating solution thus prepared is not particularly limited as long as it can be coated, and can be appropriately selected according to the situation. For example, it is diluted so that the concentration of the pressure-sensitive adhesive composition is 10% by mass or more and 60% by mass or less. In addition, when obtaining a coating liquid, addition of a dilution solvent etc. is not a necessary condition, and if a viscosity etc. which can be coated with an adhesive composition, it is not necessary to add a dilution solvent. In this case, the pressure-sensitive adhesive composition becomes a coating solution using the polymerization solvent for the acrylic polymer as a diluent solvent.

  When the intermediate layer 20 is composed of an active energy ray-curable adhesive, the active energy ray-curable adhesive that will be described later as the active energy ray-curable adhesive constituting the adhesive layer 30 should be used. Can do.

  The intermediate layer 20 preferably has transparency to active energy rays from the viewpoint of efficiently curing the pressure-sensitive adhesive layer 30 by irradiation with active energy rays.

  The thickness of the intermediate layer 20 is preferably 20 μm or more, and particularly preferably 40 μm or more. Further, the thickness is preferably 100 μm or less, and particularly preferably 80 μm or less. When the thickness of the intermediate layer 20 is 20 μm or more, the flexibility of the semiconductor processing sheet 1 becomes more excellent, and it becomes easy to expand. In addition, when the thickness is 100 μm or less, the semiconductor processing sheet 1 is less likely to vibrate during processing, and when the semiconductor member is diced using the semiconductor processing sheet 1, Chipping can be effectively suppressed.

(3) Adhesive layer The adhesive layer 30 in this embodiment is comprised from the active energy ray-curable adhesive. As long as the pressure-sensitive adhesive layer 30 can achieve the above-described conditions relating to the change rate of the adhesive force and can exhibit an adhesive force suitable for processing a semiconductor member on the semiconductor processing sheet 1, in particular. It is not limited.

  The pressure-sensitive adhesive layer 30 in the present embodiment is formed from a pressure-sensitive adhesive composition containing a polymer that does not have energy beam curability and a monomer and / or oligomer having at least one energy beam curable group. It is preferable that

  Moreover, it is also preferable that the adhesive layer 30 in this embodiment is formed from the adhesive composition containing the polymer which has active energy ray curability. The pressure-sensitive adhesive composition may further contain at least one of a monomer and / or oligomer having at least one active energy ray-curable group and a polymer not having active energy ray-curability.

  First, the pressure-sensitive adhesive layer 30 is formed from a pressure-sensitive adhesive composition containing a polymer having no active energy ray-curing property and a monomer and / or oligomer having at least one active energy ray-curable group. The case will be described below.

  As a polymer which does not have active energy ray curability, the component similar to the acrylic copolymer mentioned above can be used, for example.

  As the monomer and / or oligomer having at least one active energy ray-curable group, for example, an ester of a polyhydric alcohol and (meth) acrylic acid can be used.

  Examples of such active energy ray-curable monomers and / or oligomers include monofunctional acrylic esters such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tris. (Meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di ( Multifunctional acrylic acid esters such as (meth) acrylate and dimethyloltricyclodecane di (meth) acrylate, polyester oligo (meth) acrylate, polyurethane oligo (meth) a Relate and the like.

  The content of the active energy ray-curable monomer and / or oligomer in the pressure-sensitive adhesive composition is preferably 10 parts by mass or more with respect to 100 parts by mass of the polymer that does not have active energy ray-curing property. It is preferably 25 parts by mass or more. The content is preferably 250 parts by mass or less, particularly preferably 100 parts by mass or less, with respect to 100 parts by mass of the polymer having no active energy ray curability.

  The pressure-sensitive adhesive composition preferably contains a crosslinking agent. As a result, a good three-dimensional network structure is formed in the pressure-sensitive adhesive layer 30, and the pressure-sensitive adhesive layer 30 easily exhibits a desired cohesive force. As the crosslinking agent in this case, those described above as the crosslinking agent for forming the intermediate layer 20 can be used.

  It is preferable that content of the crosslinking agent in the adhesive composition mentioned above is 0.01 mass part or more with respect to 100 mass parts of polymers which do not have active energy ray curability. Moreover, it is preferable that the said content is 8 mass parts or less with respect to 100 mass parts of polymers which do not have active energy ray curability.

  Moreover, when using an ultraviolet-ray as an active energy ray for hardening an active energy ray hardening adhesive, it is preferable that the said adhesive composition contains a photoinitiator. Thereby, the polymerization curing time and the amount of light irradiation can be reduced.

  Specific examples of the photopolymerization initiator include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, benzoin dimethyl ketal, 2,4 -Diethylthioxanthone, 1-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, β-chloranthraquinone, (2,4,6-trimethyl) Benzyldiphenyl) phosphine oxide, 2-benzothiazole-N, N-diethyldithiocarbamate, oligo {2-hydroxy-2-methyl-1 [4- (1-propenyl) phenyl] propanone}, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl) -Propionyl) -benzyl] phenyl} -2-methyl-propan-1-one and the like. Among these, it is preferable to use 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one. The photopolymerization initiators described above may be used alone or in combination of two or more.

  The content of the photopolymerization initiator in the pressure-sensitive adhesive composition is preferably 0.1 parts by mass or more, particularly 0.5 parts by mass with respect to 100 parts by mass of the polymer having no active energy ray curability. The above is preferable. In addition, the content is preferably 10 parts by mass or less, and particularly preferably 6 parts by mass or less, with respect to 100 parts by mass of the polymer having no active energy ray curability.

  A desired additive can be added to the above-described pressure-sensitive adhesive composition as long as the above-described effects of the semiconductor processing sheet 1 according to the present embodiment are not impaired. As said additive, what was mentioned above as an additive added to the adhesive composition for forming the intermediate | middle layer 20 can be used.

  The pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 30 includes a polymer having no active energy ray-curing property, a monomer and / or an oligomer having at least one active energy ray-curable group, and optionally a cross-linking. It can be obtained by mixing an agent, a photopolymerization initiator, and other additives, but if necessary, these components can be mixed in a diluting solvent as a coating solution for the pressure-sensitive adhesive composition. Good. As said dilution solvent, what was mentioned above as a dilution solvent for preparing the coating liquid of the adhesive composition for forming the intermediate | middle layer 20 can be used.

  Next, the case where the adhesive layer 30 is formed from the adhesive composition containing the polymer which has active energy ray curability is demonstrated below. The polymer having active energy ray curability is a (meth) acrylic acid ester (co) polymer (hereinafter referred to as “active”) having a functional group (active energy ray curable group) having active energy ray curability introduced in the side chain. It is sometimes referred to as “energy-ray curable polymer”). This active energy ray-curable polymer is an acrylic copolymer described above, which contains the functional group-containing monomer unit described above as a monomer constituting the polymer, and a functional group bonded to the functional group. It is preferable that it is a thing obtained by making it react with the unsaturated group containing compound which has.

  The functional group of the unsaturated group-containing compound can be appropriately selected according to the type of functional group of the functional group-containing monomer unit of the acrylic copolymer. For example, when the functional group of the acrylic copolymer is a hydroxy group, an amino group or a substituted amino group, the functional group of the unsaturated group-containing compound is preferably an isocyanate group or an epoxy group, and the acrylic copolymer has When the functional group is an epoxy group, the functional group of the unsaturated group-containing compound is preferably an amino group, a carboxy group or an aziridinyl group.

  The unsaturated group-containing compound contains at least one, preferably 1 to 6, more preferably 1 to 4, active energy ray polymerizable carbon-carbon double bonds in one molecule. . Specific examples of such unsaturated group-containing compounds include, for example, 2-methacryloyloxyethyl isocyanate, meta-isopropenyl-α, α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, 1,1- (bisacryloyloxy Methyl) ethyl isocyanate; acryloyl monoisocyanate compound obtained by reaction of diisocyanate compound or polyisocyanate compound with hydroxyethyl (meth) acrylate; diisocyanate compound or polyisocyanate compound, polyol compound, and hydroxyethyl (meth) acrylate Acrylyl monoisocyanate compound obtained by reaction; glycidyl (meth) acrylate; (meth) acrylic acid, 2- (1-aziri And diynyl) ethyl (meth) acrylate, 2-vinyl-2-oxazoline, 2-isopropenyl-2-oxazoline, and the like.

  The unsaturated group-containing compound is preferably used in a proportion of 50 mol% or more, particularly preferably 60 mol% or more, more preferably 70 mol% or more, based on the number of moles of the functional group-containing monomer of the acrylic copolymer. It is done. The unsaturated group-containing compound is preferably a ratio of 95 mol% or less, particularly preferably 93 mol% or less, more preferably 90 mol% or less, relative to the number of moles of the functional group-containing monomer of the acrylic copolymer. Used in

  In the reaction between the acrylic copolymer and the unsaturated group-containing compound, depending on the combination of the functional group of the acrylic copolymer and the functional group of the unsaturated group-containing compound, the reaction temperature, pressure, solvent The time, the presence or absence of a catalyst, and the type of catalyst can be appropriately selected. As a result, the functional group present in the acrylic copolymer reacts with the functional group in the unsaturated group-containing compound, and the unsaturated group is introduced into the side chain in the acrylic copolymer, and the active energy ray. A curable polymer is obtained.

  The weight average molecular weight (Mw) of the active energy ray-curable polymer thus obtained is preferably 10,000 or more, particularly preferably 150,000 or more, and more preferably 200,000 or more. preferable. The weight average molecular weight (Mw) is preferably 1.5 million or less, and particularly preferably 1 million or less.

  The photopolymerization initiator and the crosslinking agent described above can be appropriately blended with the pressure-sensitive adhesive composition containing a polymer having active energy ray curability.

  The pressure-sensitive adhesive layer 30 in the present embodiment preferably has a storage elastic modulus at 23 ° C. smaller than the storage elastic modulus at 23 ° C. of the intermediate layer 20. Thereby, the semiconductor processing sheet 1 according to the present embodiment effectively suppresses the vibration of the semiconductor processing sheet 1 during processing while exhibiting better adhesive force to the semiconductor member that is the adherend. can do. When these effects are combined and dicing is performed by the semiconductor processing sheet 1, it is possible to effectively suppress the occurrence of chipping during dicing. In addition, the storage elastic modulus mentioned above in the adhesive layer 30 shall mean the storage elastic modulus in the state which the adhesive layer 30 has not hardened | cured before irradiating an active energy ray. Specifically, the storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layer 30 is preferably 0.01 MPa or more, particularly preferably 0.03 MPa or more, and more preferably 0.05 MPa or more. . Further, the storage elastic modulus is preferably 10 MPa or less, particularly preferably 5 MPa or less, and further preferably 1 MPa or less.

  The thickness of the pressure-sensitive adhesive layer 30 in the present embodiment is preferably thinner than the thickness of the intermediate layer 20. Thereby, the vibration of the semiconductor processing sheet 1 during processing can be effectively suppressed. When dicing is performed by the semiconductor processing sheet 1, generation of chipping during dicing can be effectively suppressed. Is possible. Specifically, the thickness of the pressure-sensitive adhesive layer 30 is preferably 5 μm or more, and particularly preferably 7 μm or more. Further, the thickness is preferably 30 μm or less, and particularly preferably 20 μm or less. When the thickness of the pressure-sensitive adhesive layer 30 is in the above-described range, the semiconductor processing sheet 1 exhibits a desired pressure-sensitive adhesive force on a semiconductor member as an adherend while effectively suppressing the occurrence of chipping. It becomes easy to do.

(4) Release Sheet The semiconductor processing sheet 1 according to the present embodiment is obtained by laminating the release sheet 40 on the surface of the adhesive layer 30 opposite to the intermediate layer 20 (hereinafter sometimes referred to as “adhesive surface”). May be. Thereby, the said adhesive surface can be protected until it affixes on a semiconductor member.

  The configuration of the release sheet 40 is arbitrary, and examples include a plastic film that has been subjected to a release treatment with a release agent or the like. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. As the release agent, silicone-based, fluorine-based, long-chain alkyl-based, and the like can be used, and among these, a silicone-based material that is inexpensive and provides stable performance is preferable.

  Although there is no restriction | limiting in particular about the thickness of the peeling sheet 40, Usually, they are 20 micrometers or more and 250 micrometers or less.

(5) Other members In the semiconductor processing sheet 1 according to the present embodiment, an adhesive layer may be laminated on the adhesive surface of the adhesive layer 30. In this case, the semiconductor processing sheet 1 according to the present embodiment can be used as a dicing die bonding sheet by including the adhesive layer as described above. In such a semiconductor processing sheet 1, a semiconductor member is attached to the surface of the adhesive layer opposite to the pressure-sensitive adhesive layer 30, and the adhesive layer is diced together with the semiconductor member, whereby the semiconductor member is separated into pieces. The chip thus obtained can be obtained in a state where the separated adhesive layers are laminated. The chip can be easily fixed to an object on which the chip is mounted by the separated adhesive layer. As a material constituting the above-described adhesive layer, a material containing a thermoplastic resin and a low molecular weight thermosetting adhesive component, a material containing a B-stage (semi-cured) thermosetting adhesive component, etc. It is preferable to use it.

  In the semiconductor processing sheet 1 according to this embodiment, a protective film forming layer may be laminated on the adhesive surface of the adhesive layer 30. In this case, the semiconductor processing sheet 1 according to the present embodiment can be used as a protective film forming and dicing sheet. In such a semiconductor processing sheet 1, a semiconductor member is attached to the surface of the protective film forming layer opposite to the pressure-sensitive adhesive layer 30, and the protective film forming layer is diced together with the semiconductor member. Further, a chip on which a protective film forming layer is laminated can be obtained. As the material to be cut, one having a circuit formed on one side is preferably used. In this case, a protective film forming layer is usually laminated on the surface opposite to the surface on which the circuit is formed. . The individual protective film forming layers are cured at a predetermined timing, whereby a protective film having sufficient durability can be formed on the chip. The protective film forming layer is preferably made of an uncured curable adhesive.

2. Physical Properties of Semiconductor Processing Sheet In the semiconductor processing sheet 1 according to the present embodiment, the adhesive force F1 defined with respect to the above-described adhesive force change rate, that is, a laminate formed by attaching the semiconductor processing sheet 1 to a silicon wafer. The adhesive force F1 of the semiconductor processing sheet 1 to the silicon wafer after irradiating the semiconductor processing sheet 1 with active energy rays to cure the adhesive layer is 20 mN / 25 mm or more. It is preferable that it is 100 mN / 25 mm or more especially. The adhesive force F1 is preferably 1000 mN / 25 mm or less, and particularly preferably 600 mN / 25 mm or less.

  In addition, in the semiconductor processing sheet 1 according to the present embodiment, the adhesive processing F2 defined with respect to the above-mentioned adhesive force change rate, that is, a laminate formed by attaching the semiconductor processing sheet 1 to a silicon wafer The adhesive force of the semiconductor processing sheet 1 to the silicon wafer after curing the adhesive layer by irradiating the active sheet 1 with the active energy ray and subsequently heating the laminate at 120 ° C. for 1 hour F2 is preferably 20 mN / 25 mm or more, particularly preferably 100 mN / 25 mm or more. The adhesive force F2 is preferably 1000 mN / 25 mm or less, particularly preferably 600 mN / 25 mm or less.

  When the adhesive force F1 and the adhesive force F2 described above are in the above ranges, the above-described adhesive force change rate can be easily adjusted to the above-described range, whereby the semiconductor processing sheet 1 has more excellent heat resistance. It will be demonstrated. Moreover, since the adhesive force F2 is in the above-described range, the semiconductor processing sheet 1 is unlikely to have an excessively high adhesive force after heating, and thus the processed semiconductor member is easily peeled off. Become.

In addition, as irradiation amount of the active energy ray irradiated to a laminated body in the definition of the adhesive force F1 and adhesive force F2 mentioned above, what is necessary is just the quantity which can fully harden the adhesive layer 30, for example, illumination intensity is 50 mW / Cm ² or more is preferable. Moreover, it does not specifically limit about the upper limit of illumination intensity, For example, what is necessary is just 1000 mW / cm < ² > or less. Amount is preferably at 50 mJ / cm ² or more, particularly preferably at 80 mJ / cm ² or more, and further preferably not 100 mJ / cm ² or more. Moreover, although it does not specifically limit about the upper limit of light quantity, For example, it is preferable that it is 2000 mJ / cm < ² > or less, It is especially preferable that it is 1000 mJ / cm < ² > or less, Furthermore, it is 500 mJ / cm < ² > or less. preferable.

3. Manufacturing method of semiconductor processing sheet The manufacturing method of the semiconductor processing sheet 1 according to the present embodiment is not particularly limited. For example, after manufacturing the laminated body provided with the base material 10 and the intermediate | middle layer 20, the sheet | seat 1 for semiconductor processing can be obtained by laminating | stacking the adhesive layer 30 on the surface side of the intermediate | middle layer 20 in the said laminated body.

  In the case where the intermediate layer 20 is composed of a pressure-sensitive adhesive, an example of a method for producing a laminate including the base material 10 and the intermediate layer 20 includes the above-described pressure-sensitive adhesive composition, and optionally further contains a solvent or a dispersion medium. The coating liquid to be prepared is prepared, and a die coater, a curtain coater, a spray coater, a slit coater, a knife coater, and an applicator are formed on the release-treated surface (hereinafter sometimes referred to as “release surface”) of the release sheet 40 described above. The laminated body which consists of the intermediate | middle layer 20 and the peeling sheet 40 can be formed by apply | coating the coating liquid by etc., forming a coating film, and drying the said coating film. The properties of the coating liquid are not particularly limited as long as it can be applied, and may contain a component for forming the intermediate layer 20 as a solute or a dispersoid. After obtaining the laminate, the base layer 10, the intermediate layer 20, and the release sheet 40 are bonded to the base 10 with the surface opposite to the release sheet 40 side of the intermediate layer 20. A laminated body can be obtained. Moreover, the said coating liquid is apply | coated on the single side | surface of the base material 10, a coating film is formed, and the laminated body by which the base material 10 and the intermediate | middle layer 20 were laminated | stacked by drying the said coating film was obtained. Also good.

  As an example of a manufacturing method of a laminate including the base material 10 and the intermediate layer 20 when the intermediate layer 20 is composed of the resin film described above, the intermediate layer 20 is configured on one side of the base material 10. And a method of coextruding the material for constituting the base material 10 and the material for constituting the intermediate layer 20.

  As a method for forming the pressure-sensitive adhesive layer 30, for example, a coating liquid containing the pressure-sensitive adhesive composition described above and, if desired, further containing a solvent or a dispersion medium is prepared, and the coating is applied onto the release surface of the release sheet 40 described above. The laminated body which consists of the adhesive layer 30 and the peeling sheet 40 can be formed by apply | coating a process liquid, forming a coating film, and drying the said coating film.

  And the surface by the side of the intermediate | middle layer 20 of the laminated body provided with the base material 10 and the intermediate | middle layer 20 which were produced as mentioned above (When the release sheet 40 is laminated | stacked, the intermediate | middle which peeled and exposed the said release sheet 40) The substrate 10, the intermediate layer 20, and the pressure-sensitive adhesive layer 30 are bonded by bonding the exposed surface of the layer 20) and the surface on the pressure-sensitive adhesive layer 30 side of the laminate composed of the pressure-sensitive adhesive layer 30 and the release sheet 40. The semiconductor processing sheet 1 formed by laminating the release sheet 40 can be obtained.

  When at least one of the above-described coating liquid for forming the intermediate layer 20 and the above-described coating liquid for forming the pressure-sensitive adhesive layer 30 contains a crosslinking agent, the above drying conditions (temperature) By changing the time, etc.) or by separately providing a heat treatment, the cross-linking reaction between the polymer in the coating film and the cross-linking agent proceeds, and the intermediate layer 20 and the pressure-sensitive adhesive layer 30 are cross-linked at a desired density. A structure may be formed. In order to sufficiently advance the crosslinking reaction, curing may be performed at a desired stage by, for example, leaving it in an environment of 23 ° C. and 50% relative humidity for several days by the above method.

4). Method for Using Semiconductor Processing Sheet The semiconductor processing sheet 1 according to the present embodiment is preferably used for processing a semiconductor member. Examples of the semiconductor member include a semiconductor wafer and a semiconductor package. Moreover, the object of processing by the semiconductor processing sheet 1 according to the present embodiment is not limited to the semiconductor member, and may be a glass member such as a glass plate. Examples of processing performed using the semiconductor processing sheet 1 according to the present embodiment include back grinding, dicing, expanding, and pick-up, as well as vapor deposition, sputtering, and dehumidification for semiconductor members or processed products thereof. The process with a heating is mentioned. Moreover, the heating test for confirming the reliability in a high temperature environment with respect to a semiconductor member or its processed material can also be performed on the sheet | seat 1 for semiconductor processing which concerns on this embodiment.

  Hereinafter, a method for manufacturing a semiconductor device by processing a semiconductor wafer using the semiconductor processing sheet 1 according to the present embodiment will be described. The manufacturing method includes a wafer preparation step of providing a semiconductor wafer on the adhesive surface of the semiconductor processing sheet 1, and cutting the semiconductor wafer in the thickness direction to obtain a plurality of semiconductor chips obtained by dividing the semiconductor wafer into individual pieces. A dicing step, a heating step for heating the semiconductor chip on the semiconductor processing sheet 1, an expanding step for stretching the semiconductor processing sheet 1 to separate the plurality of semiconductor chips from each other, and a semiconductor processing sheet 1 for separating the separated semiconductor chips. A pick-up process for picking up individual items is provided.

(1) Wafer Preparation Step First, as a wafer preparation step, a semiconductor wafer is provided on the adhesive surface of the semiconductor processing sheet 1. At this time, a ring frame may be further attached to the peripheral portion of the adhesive surface.

(2) Dicing Step Next, as the dicing step, the semiconductor wafer is diced on the semiconductor processing sheet 1 to obtain a plurality of semiconductor chips obtained by dividing the semiconductor wafer. The dicing method is not particularly limited and can be performed by a general method. For example, by using a dicing blade or irradiating laser light, the semiconductor wafer can be completely divided and separated into a plurality of semiconductor chips.

  In the semiconductor processing sheet 1 according to the present embodiment, the product of the expansion coefficient and the thickness of the base material 10 is in the above-described range, and the storage elastic modulus at 23 ° C. of the intermediate layer 20 is in the above-described range. Thereby, the vibration of the semiconductor processing sheet 1 during the dicing can be suppressed. Thereby, collision between semiconductor chips to be formed is suppressed, and as a result, occurrence of chipping in the semiconductor chip can be suppressed.

(3) Heating step Next, as a heating step, the semiconductor chip on the semiconductor processing sheet 1 is heated. The purpose of the heating is not particularly limited, and may be, for example, secondary heating accompanying vapor deposition or sputtering on a semiconductor chip or even when baking a semiconductor chip for dehumidification. Alternatively, it may be heating of a semiconductor chip for a durability test against a high temperature environment.

  The method for heating is not particularly limited, and is determined according to the purpose of heating. In particular, when performing an endurance test in a high temperature environment, it is preferable to heat the semiconductor processing sheet 1 by placing the surface opposite to the surface on which the semiconductor chips are stacked on a heating table. The specific method of heating using the heating table is as shown in the test examples described later.

  The heating temperature can be set according to the purpose of heating, but is preferably 80 ° C. or higher, and particularly preferably 100 ° C. or higher. Moreover, it is preferable that the said temperature is 300 degrees C or less, and it is especially preferable that it is 270 degrees C or less. Although the heating time can also be set according to the purpose of heating, for example, it is preferably 10 minutes or more, and particularly preferably 30 minutes or more. The heating time is preferably 25 hours or less, and particularly preferably 10 hours or less.

  In the semiconductor processing sheet 1 according to the present embodiment, the product of the expansion coefficient and the thickness of the base material 10 is in the above-described range, and the storage elastic modulus at 23 ° C. of the intermediate layer 20 is in the above-described range. Thus, deformation during heating is suppressed. Moreover, in the sheet | seat 1 for semiconductor processing which concerns on this embodiment, since the adhesive force change rate mentioned above is the range mentioned above, it becomes a thing with which adhesive force does not change easily before and after the said heating. Thus, according to the semiconductor processing sheet 1 according to the present embodiment, the movement of the semiconductor chip on the semiconductor processing sheet 1 and the unintentional separation and dropping of the semiconductor chip from the semiconductor processing sheet 1 are suppressed, and heating is performed. A process can be performed appropriately. Thus, the semiconductor processing sheet 1 according to this embodiment has excellent heat resistance.

(4) Expanding process Next, as an expanding process, the semiconductor processing sheet 1 is stretched to separate a plurality of semiconductor chips from each other. The expanding method is not particularly limited and can be performed by a general method.

  In the semiconductor processing sheet 1 according to the present embodiment, the product of the expansion coefficient and the thickness of the base material 10 is in the above-described range, and the storage elastic modulus at 23 ° C. of the intermediate layer 20 is in the above-described range. Thus, the semiconductor processing sheet 1 has excellent flexibility. As a result, the semiconductor processing sheet 1 can be expanded well, and the semiconductor chips can be sufficiently separated.

(5) Pickup process Finally, the separated semiconductor chips are individually picked up from the semiconductor processing sheet 1 as a pickup process. The pickup method is not particularly limited, and can be performed by a general method.

  Moreover, in the semiconductor processing sheet 1 according to the present embodiment, since the pressure-sensitive adhesive layer 30 is composed of an active energy ray-curable pressure-sensitive adhesive, the active energy ray is applied to the pressure-sensitive adhesive layer 30 before picking up. Is preferably irradiated. Thereby, the adhesive force with respect to the semiconductor chip of the sheet | seat 1 for semiconductor processing falls, and it becomes possible to peel a semiconductor chip favorably from the sheet | seat 1 for semiconductor processing.

As the active energy ray in the active energy ray irradiation, for example, an electromagnetic wave or a charged particle beam having an energy quantum can be used, and specifically, an ultraviolet ray or an electron beam can be used. In particular, ultraviolet rays that are easy to handle are preferred. Irradiation of ultraviolet rays, a high-pressure mercury lamp, can be performed by a xenon lamp, LED, etc., the dose of ultraviolet ray is illuminance 50 mW / cm ² or more, and preferably 1000 mW / cm ² or less. Further, the light amount is preferably at 50 mJ / cm ² or more, particularly preferably at 80 mJ / cm ² or more, and further preferably not 100 mJ / cm ² or more. Further, the light amount is preferably 2000 mJ / cm ² or less, particularly preferably 1000 mJ / cm ² or less, and more preferably 500 mJ / cm ² or less. On the other hand, the electron beam irradiation can be performed by an electron beam accelerator or the like, and the electron beam irradiation amount is preferably 10 krad or more and 1000 krad or less.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  For example, other layers may be provided on the surface of the substrate 10 opposite to the intermediate layer 20, between the substrate 10 and the intermediate layer 20, and between the intermediate layer 20 and the adhesive layer 30.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
(1) Preparation of pressure-sensitive adhesive composition for forming an intermediate layer An acrylic copolymer is prepared by copolymerizing 80 parts by mass of 2-ethylhexyl acrylate and 20 parts by mass of 2-hydroxyethyl acrylate by a liquid polymerization method. Got. In addition, it was 600,000 when the weight average molecular weight (Mw) of the said acrylic copolymer was measured by the method mentioned later.

  35 parts by mass of the obtained acrylic copolymer and 3.75 parts by mass of trimethylolpropane-modified tolylene diisocyanate (TDI-TMP) (product name “Coronate L” manufactured by Tosoh Corporation) as a crosslinking agent were mixed. Thus, a coating solution of the pressure-sensitive adhesive composition for forming the intermediate layer (pressure-sensitive adhesive composition A1) was obtained.

(2) Preparation of pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer 50 parts by mass of 2-ethylhexyl acrylate, 40 parts by mass of methacrylic acid, and 10 parts by mass of acrylic acid are copolymerized by a liquid polymerization method to obtain acrylic. A system copolymer was obtained. In addition, it was 600,000 when the weight average molecular weight (Mw) of the said acrylic copolymer was measured by the method mentioned later.

  35 parts by mass of the obtained acrylic copolymer and 17.1 parts by mass of a multifunctional ultraviolet curable resin as an active energy ray-curable oligomer (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., product name “purple light UV-5806”) Part, 1.875 parts by mass of trimethylolpropane-modified tolylene diisocyanate (TDI-TMP) (product name “Coronate L”, manufactured by Tosoh Corporation) as a crosslinking agent, and 2-hydroxy-1- as a photopolymerization initiator 0.01 part by mass of {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one (manufactured by BASF, product name “Irgacure 127”) Were mixed to obtain a coating solution of the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer (pressure-sensitive adhesive composition B1).

(3) Production of sheet for semiconductor processing Peeling treatment of a release sheet (product name “SP-PET381031”, manufactured by Lintec Corporation) in which one main surface of a polyethylene terephthalate film having a thickness of 38 μm is peeled by a silicone-based release agent On the surface, while adjusting the gap using an applicator, the coating solution of the pressure-sensitive adhesive composition for forming the intermediate layer prepared in the above step (1) was applied and dried at 100 ° C. for 2 minutes, An intermediate layer having a thickness of 60 μm was formed to obtain a first laminate composed of a release sheet and an intermediate layer.

  Next, the surface on the intermediate layer side of the first laminate was pasted on one surface of a polypropylene film (manufactured by Diaplus Film Co., Ltd., product name “PL109C”, thickness: 80 μm) as a base material. . Thereby, the 2nd laminated body by which a base material, an intermediate | middle layer, and a peeling sheet were laminated | stacked in this order was obtained.

  In addition, an applicator is placed on the release treatment surface of a release sheet (product name “SP-PET381031” manufactured by Lintec Corporation) in which one main surface of a polyethylene terephthalate film having a thickness of 38 μm is release-treated with a silicone-based release agent. Adhesive having a thickness of 10 μm by applying the coating composition of the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer prepared in the above step (2) while drying the gap at 100 ° C. for 2 minutes while adjusting the gap. An agent layer was formed to obtain a third laminate composed of a release sheet and an adhesive layer.

  The surface on the pressure-sensitive adhesive layer side in the obtained third laminate, and the release sheet is peeled from the second laminate obtained as described above, and the exposed intermediate layer-side surface at a temperature of 23 ° C. The sheet | seat for semiconductor processing was obtained by bonding using a roll laminator.

Here, the above-mentioned weight average molecular weight (Mw) is a polystyrene-reduced weight average molecular weight measured under the following conditions (GPC measurement) using gel permeation chromatography (GPC).
<Measurement conditions>
GPC measurement device: manufactured by Tosoh Corporation, HLC-8020
GPC column (passed in the following order): TSK guard column HXL-H manufactured by Tosoh Corporation
TSK gel GMHXL (× 2)
TSK gel G2000HXL
・ Measurement solvent: Tetrahydrofuran ・ Measurement temperature: 40 ° C.

[Examples 2-3, Comparative Examples 1-2]
A semiconductor processing sheet was produced in the same manner as in Example 1 except that the base material shown in Table 1 was used.

[Comparative Example 3]
An acrylic copolymer was obtained by copolymerizing 80 parts by mass of 2-ethylhexyl acrylate and 20 parts by mass of 2-hydroxyethyl acrylate by a liquid polymerization method. In addition, it was 600,000 when the weight average molecular weight (Mw) of the said acrylic copolymer was measured by the method mentioned above.

  35 parts by mass of the obtained acrylic copolymer and 0.075 parts by mass of trimethylolpropane-modified tolylene diisocyanate (TDI-TMP) (product name “Coronate L” manufactured by Tosoh Corporation) as a crosslinking agent are mixed. Thus, a coating solution of the pressure-sensitive adhesive composition for forming the intermediate layer (pressure-sensitive adhesive composition A2) was obtained.

  Using the pressure-sensitive adhesive composition, a semiconductor processing sheet was produced in the same manner as in Example 1, except that an intermediate layer was formed.

[Comparative Example 4]
An acrylic copolymer was obtained by copolymerizing 50 parts by mass of 2-ethylhexyl acrylate, 40 parts by mass of methacrylic acid, and 10 parts by mass of acrylic acid by a liquid polymerization method. In addition, it was 600,000 when the weight average molecular weight (Mw) of the said acrylic copolymer was measured by the method mentioned later.

  35 parts by mass of the obtained acrylic copolymer, 17.69 parts by mass of a trifunctional urethane acrylate oligomer (manufactured by Dainichi Seika Kogyo Co., Ltd., product name “EXL810TL”) as an energy ray-curable oligomer, and a crosslinking agent Of 1.75 parts by mass of trimethylolpropane-modified tolylene diisocyanate (TDI-TMP) (product name “Coronate L”, manufactured by Tosoh Corporation), and pressure-sensitive adhesive composition for forming a pressure-sensitive adhesive layer (pressure-sensitive adhesive composition) A coating solution of product B2) was obtained.

  A semiconductor processing sheet was produced in the same manner as in Example 1 except that the pressure-sensitive adhesive composition was used to form a pressure-sensitive adhesive layer.

[Comparative Example 5]
The surface on the pressure-sensitive adhesive layer side in the third laminate produced as described above is formed on one surface of a polypropylene film (Diaplus Film, product name “PL109C”, thickness: 80 μm) as a base material. By sticking, the sheet | seat for semiconductor processing with which a base material, an adhesive layer, and a peeling sheet were laminated | stacked in this order was manufactured.

[Comparative Examples 6-7]
A semiconductor processing sheet was produced in the same manner as in Example 1 except that the base material shown in Table 1 was used.

[Test Example 1] (Measurement of tensile modulus of base material)
The base materials used in Examples and Comparative Examples were cut into 15 mm × 140 mm test pieces, and the tensile modulus at a temperature of 23 ° C. and a relative humidity of 50% was measured according to JIS K7161: 2014. Specifically, the test piece was set to a distance between chucks of 100 mm with a tensile tester (manufactured by Orientec Co., Ltd., product name “Tensilon RTA-T-2M”), and then a tensile test at a speed of 200 mm / min. The tensile modulus (MPa) was measured. The measurement was performed in both the extrusion direction (MD) during molding of the base material and the direction (CD) perpendicular thereto, and the average value of these measurement results was taken as the tensile modulus. The results are shown in Table 1.

[Test Example 2] (Measurement of expansion coefficient of base material)
A test piece having a width of 4.5 mm and a length of 15 mm was cut out from the base material used in the examples and comparative examples. At this time, a test piece for MD cut out so that the MD direction of the base material became the length direction and a test piece for CD cut out so that the CD direction of the base material became the length direction were prepared. For each of these test pieces, a 0.2 g load was applied in the length direction using a thermomechanical analyzer (TMA) (manufactured by Bruker AXS, product name “TMA4000SA”). The initial dimension L ₀ (mm) when heated from 23 ° C. to 120 ° C. at a heating temperature of 10 ° C./min and the dimension L (mm) when reaching 120 ° C. are measured, and the following formula (2)
Expansion rate (%) = {(L−L ₀ ) / L ₀ } × 100 (2)
The expansion coefficient was calculated from Of the expansion coefficients obtained for the MD direction and the CD direction, the larger value was taken as the expansion coefficient (%) of the substrate. The results are shown in Table 1.

  Moreover, the product (% · μm) of the expansion coefficient (%) of the base material obtained as described above and the thickness (μm) of the base material was calculated. The results are also shown in Table 1.

[Test Example 3] (Storage elastic modulus of intermediate layer and pressure-sensitive adhesive layer)
Using the 1st laminated body which consists of the peeling sheet and intermediate | middle layer which were produced in Examples 1-3 and Comparative Examples 1-4 and 6-7, the said intermediate | middle layer was laminated | stacked several layers and the intermediate | middle of thickness 3mm A layer stack was obtained. From this intermediate layer laminate, a cylinder having a diameter of 8 mm (height 3 mm) was punched out and used as a sample for the intermediate layer.

About the sample for intermediate layers, in accordance with JIS K7244-6: 1999, a storage elastic modulus (MPa) under the following conditions was obtained by a torsional shear method using a viscoelasticity measuring device (product name “DYNAMIC ANALAYZER” manufactured by REOMETRIC). ) Was measured. The results are shown in Table 1.
Measurement frequency: 1Hz
Measurement temperature: 23 ° C

  Moreover, using the 3rd laminated body which consists of a peeling sheet and an adhesive layer produced in the Example and the comparative example, the said adhesive layer was laminated | stacked several layers and the adhesive layer laminated body of thickness 3mm was obtained. It was. From this pressure-sensitive adhesive layer laminate, a cylinder having a diameter of 8 mm (height 1 mm) was punched out, and this was used as a sample for the pressure-sensitive adhesive layer. The storage elastic modulus (MPa) of the pressure-sensitive adhesive layer sample was also measured in the same manner as described above. The results are shown in Table 1.

[Test Example 4] (Evaluation of chipping)
(1) Fabrication of a semiconductor package After forming a circuit pattern on a copper foil in a copper foil-clad laminate (manufactured by Mitsubishi Gas Chemical Company, product name “CCL-HL830”, copper foil thickness: 18 μm), on the pattern A substrate (product name “LN001E-001 PCB (Au) AUS303” manufactured by Chino Giken Co., Ltd.) obtained by laminating a solder resist (manufactured by Taiyo Ink, product name “PSR-4000 AUS303”) was prepared.

  Without mounting a chip on the substrate, using a sealing device (product name “MPC-06M TriAl Press” manufactured by Apic Yamada), mold resin (product name “KE-1100AS3” manufactured by Kyocera Chemical Co., Ltd.) ) Was sealed in a rectangular shape with a sealing thickness of 400 μm and a sealing size of 45 mm × 137 mm. Thereafter, the mold resin was cured by heating at 175 ° C. for 5 hours to obtain a semiconductor package.

(2) Dicing The release sheet was peeled from the semiconductor processing sheets prepared in the examples and comparative examples, and the multi-wafer mounter (product name “Adwill RAD-2700F, manufactured by Lintec Corporation) was applied to the adhesive surface of the exposed adhesive layer. / 12 "), the semiconductor package obtained in the above step (1) is parallel to the semiconductor processing sheet flow direction and the long side direction of the semiconductor package, and the semiconductor package is the center of the semiconductor processing sheet. So as to be positioned at a temperature of 23 ° C.

  Furthermore, a ring frame for dicing (manufactured by Disco Corporation, product name “2-8-1”) was attached to the peripheral portion of the adhesive surface of the semiconductor processing sheet (position not overlapping the semiconductor package).

Next, the semiconductor package was diced under the following conditions.
<Dicing conditions>
・ Dicing machine: DISCO, product name “DFD-6362”
・ Blade: DISCO, product name “NBC-ZH2050-27HECC”
・ Blade rotation speed: 30000rpm
Cutting speed: 50 mm / min Cutting depth: Cutting depth for semiconductor processing sheet: 80 μm
・ Dicing size: 3mm x 3mm

(3) Evaluation of chipping About the back surface of 50 pieces of semiconductor package cut pieces obtained by the above dicing, the presence or absence of chipping (chipping) of a size of 20 μm or more was confirmed, and chipping was performed based on the following criteria. evaluated. The results are shown in Table 2.
◯: There were no chippings.
X: One or more chippings were found.

[Test Example 5] (Evaluation of deformation during heating)
The semiconductor processing sheets produced in the examples and comparative examples were diced in the same manner as in the steps (1) and (2) of Test Example 4. Then, the semiconductor package and ring frame after dicing are mounted on the mounting table of the multi-wafer mounter (Lintec Co., Ltd., “Adwill RAD-2700F / 12”) that has been heated to 120 ° C. and vacuum is ON. The semiconductor processing sheet in a state of being attached was allowed to stand by using a transfer arm so that the surface opposite to the attached surface was in contact with the mount table. Then, after confirming the state of the semiconductor processing sheet, the semiconductor processing sheet was separated from the mount table. This operation was performed on 10 sets of semiconductor processing sheets with the semiconductor package after dicing and the ring frame attached thereto.

Based on the following criteria, deformation of the semiconductor processing sheet during heating was evaluated with respect to the state of the semiconductor processing sheet when left on the mount table. The results are shown in Table 2.
◯: All 10 sets were vacuum-sucked to the mount table, and there was no deformation such as wrinkles at the position of the outer periphery of the mount table, or only a part was recognized.
(Triangle | delta): The number of the sets vacuum-sucked to the mount table was 9 sets or less and 8 sets or more.
X: The number of sets completely vacuum-adsorbed to the mount table was 7 sets or less.

[Test Example 6] (Evaluation of expandability)
One set of the semiconductor processing sheet with the dicing semiconductor package and the ring frame attached after performing the test example 5 is installed in an expanding apparatus (product name “SE-100” manufactured by JCM). Then, the ring frame was pulled down at a speed of 5 mm / s with two types of withdrawal amounts of 7 mm and 10 mm. And the expandability of the sheet | seat for semiconductor processing was evaluated based on the following references | standards. The results are shown in Table 2.
○: In both cases where the withdrawal amount was 7 mm and 10 mm, the withdrawal could be performed satisfactorily.
Δ: In the case of the withdrawal amount of 10 mm, the semiconductor processing sheet peeled off from the ring frame, or the withdrawal could not be performed at the set speed, but in the case of the withdrawal amount of 7 mm, the withdrawal could be performed satisfactorily.
X: In both cases where the amount of withdrawal was 7 mm and 10 mm, there was a problem that the semiconductor processing sheet was peeled off from the ring frame or could not be pulled out at a set speed.

[Test Example 7] (Measurement of adhesive strength)
The release sheet was peeled from the semiconductor processing sheets produced in the examples and comparative examples, and the adhesive surface of the exposed adhesive layer and the mirror surface of the mirror-processed silicon wafer were subjected to a temperature of 23 ° C. and a relative humidity of 50. In a 2% environment, they were pasted together using a 2 kg rubber roller and allowed to stand for 20 minutes. Thereafter, the pressure-sensitive adhesive layer in the semiconductor processing sheet was irradiated with ultraviolet rays through the substrate under the following conditions. This obtained the sample for adhesive force measurement.
<Ultraviolet irradiation conditions>
・ Use of high pressure mercury lamp ・ Illuminance 230mW / cm ² , Light quantity 190mJ / cm ²
・ Uses UVGraph-A1 made by Eye Graphics as UV illuminance / light meter

  In the obtained adhesive force measurement sample, the workpiece processing sheet was peeled off from the silicon wafer at a peeling speed of 300 mm / min and a peeling angle of 180 °, and the silicon wafer was peeled off by 180 ° according to JIS Z0237: 2009. The adhesive force (mN / 25 mm) to was measured. The measurement results are shown in Table 2 as the adhesive strength before heating.

  Moreover, the sample for adhesive force measurement obtained similarly to the above was heated at 120 degreeC for 1 hour using oven. About the sample for adhesive strength measurement after the said heating, the adhesive force (mN / 25mm) with respect to a silicon wafer was measured similarly to the above. The measurement results are shown in Table 2 as the adhesive strength after heating.

Furthermore, about the adhesive force before heating (F1) and the adhesive strength after heating (F2) obtained as described above, the following formula (1)
Adhesive force change rate = (F2 / F1) × 100 (1)
From the above, the adhesive force change rate (%) was calculated. The results are shown in Table 2.

Details of the abbreviations and the like described in Table 1 are as follows.
PP-1: Polypropylene film (Diaplus Film, product name “PL109C”, thickness: 80 μm)
PBT: Soft polybutylene terephthalate film (manufactured by Aussie Films, product name “BS-80”, thickness: 80 μm)
PP-2: Polypropylene film (manufactured by Diaplus Film, product name “PL105”, thickness: 80 μm)
PET: Polyethylene terephthalate film (Toyobo, product name “Cosmo Shine A4100”, thickness: 100 μm)
EMAA: ethylene-methacrylic acid copolymer film (manufactured by Achilles, product name “EANU80-AL-ND”, thickness: 80 μm)
PP-3: Polypropylene film (Diaplus Film, product name “PL109C”, thickness: 140 μm)
PP-4: Polypropylene film (Diaplus Film, product name “PL105”, thickness: 140 μm)

  As can be seen from Table 2, the chip for semiconductor processing obtained in the examples was able to suppress chipping well. In addition, the semiconductor processing sheets obtained in the examples were able to expand well and were excellent in flexibility. Furthermore, the semiconductor processing sheets obtained in the examples were not easily deformed when vacuum-adsorbed on a heating table, and the change in adhesive force due to heating was small, and the heat resistance was excellent.

  The semiconductor processing sheet of the present invention can be suitably used in a method for manufacturing a semiconductor device including a dicing step, a heating step, and a pickup step.

DESCRIPTION OF SYMBOLS 1 ... Sheet | seat for semiconductor processing 10 ... Base material 20 ... Intermediate | middle layer 30 ... Adhesive layer 40 ... Release sheet

Claims (9)

A semiconductor processing sheet comprising: a base material; an intermediate layer laminated on one side of the base material; and an adhesive layer laminated on a surface opposite to the base material in the intermediate layer,
Expansion rate (%) when the material of the base material is heated from 23 ° C. to 120 ° C. at a temperature rising temperature of 10 ° C./min under a load of 0.2 g using a thermomechanical analyzer, and the base material The product with the thickness (μm) is −20% · μm or more and 120% · μm or less,
The storage elastic modulus at 23 ° C. of the intermediate layer is 0.05 MPa or more and 200 MPa or less,
The pressure-sensitive adhesive layer is composed of an active energy ray-curable pressure-sensitive adhesive,
About the laminated body formed by sticking the semiconductor processing sheet to a silicon wafer, the silicon of the semiconductor processing sheet after the adhesive layer is cured by irradiating the semiconductor processing sheet with active energy rays The adhesive strength to the wafer is F1,
For the laminate formed by attaching the semiconductor processing sheet to a silicon wafer, the adhesive layer is cured by irradiating the semiconductor processing sheet with an active energy ray. When the adhesive force of the semiconductor processing sheet to the silicon wafer after heating for a time is F2,
Following formula (1)
Adhesive force change rate = (F2 / F1) × 100 (1)
The semiconductor processing sheet characterized in that the rate of change in adhesive force calculated from the above is 2% or more and 200% or less.   The semiconductor processing sheet according to claim 1, wherein the intermediate layer has a thickness of 20 μm or more and 100 μm or less.   The semiconductor processing sheet according to claim 1, wherein a thickness of the pressure-sensitive adhesive layer is thinner than a thickness of the intermediate layer.   The semiconductor processing sheet according to claim 3, wherein the pressure-sensitive adhesive layer has a thickness of 5 μm or more and 30 μm or less.   The sheet | seat for semiconductor processing as described in any one of Claims 1-4 whose storage elastic modulus in 23 degreeC of the said adhesive layer is smaller than the storage elastic modulus in 23 degreeC of the said intermediate | middle layer.   The sheet for semiconductor processing according to claim 5, wherein a storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layer is 0.01 MPa or more and 10 MPa or less.   The thickness of the said base material is 10 micrometers or more and 200 micrometers or less, The sheet | seat for semiconductor processing as described in any one of Claims 1-6 characterized by the above-mentioned.   8. The semiconductor processing sheet according to claim 1, wherein the base material has a tensile elastic modulus at 23 ° C. of 100 MPa or more and 1000 MPa or less.   The said intermediate | middle layer is comprised from the adhesive which does not have active energy ray curability, The sheet | seat for semiconductor processing as described in any one of Claims 1-8 characterized by the above-mentioned.

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