JP6562172B2 - Resin film forming sheet and resin film forming composite sheet - Google Patents

Description

  The present invention relates to a resin film forming sheet and a resin film forming composite sheet.

  In recent years, semiconductor devices have been manufactured using a so-called face-down mounting method. In the face-down method, a semiconductor chip (hereinafter simply referred to as “chip”) having electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to a substrate. For this reason, the surface opposite to the circuit surface of the chip (hereinafter also referred to as “the back surface of the chip”) may be exposed.

A resin film made of an organic material is formed on the exposed back surface of the chip and may be taken into the semiconductor device as a chip with a resin film. The resin film is used as a protective film to prevent cracking after the dicing process or packaging, or to bond the obtained chip onto another member such as a die pad part or another semiconductor chip. Formed as a film.
Generally, this chip with a resin film is formed by applying a solution of a resin-containing composition to the back surface of a wafer by spin coating or the like to form a coating film, and then drying and curing the coating film. It is manufactured by forming a film and dicing the obtained wafer with a resin film.

Various resin film forming sheets have been proposed as a material for forming a protective film or an adhesive film provided on the back surface of the chip or the back surface of the wafer.
For example, Patent Document 1 discloses two energy beam curable protective film forming layers including an acrylic copolymer component, an energy beam curable component, a dye or pigment, an inorganic filler, and a photopolymerization initiator. A film for protecting a chip having a configuration sandwiched between two release sheets is disclosed.
According to the description of Patent Document 1, the film for chip protection can form a protective film with improved laser marking recognizability, hardness, and adhesion with a wafer by irradiation with energy rays. The process can be simplified as compared with conventional film for chip protection.

Patent Document 2 discloses a dicing tape having a dicing tape having a base material and an adhesive layer, and a wafer back surface protective film colored and having a predetermined elastic modulus on the adhesive layer of the dicing tape. A body-type wafer back surface protective film is disclosed.
According to the description in Patent Document 2, the wafer back surface protective film can exhibit excellent holding force with the semiconductor wafer in the dicing process of the semiconductor wafer.

JP 2009-138026 A JP 2010-199543 A

By the way, in the process of applying the protective film disclosed in Patent Documents 1 and 2 to the wafer, the protective film is attached so that the position of application of the protective film may be shifted or foreign substances may be included without noticing the foreign substances on the wafer. If stuck, it is difficult to peel off the protective film and rework the wafer.
The protective films disclosed in Patent Documents 1 and 2 are intended to improve adhesion to the wafer at the time of pasting and holding power with the wafer after pasting. Since the adhesion to the wafer is high, there is a problem in reworkability. If the protective film once stuck on the wafer is forcibly peeled off, the wafer may be damaged by the peeling force or a part of the protective film may remain on the wafer. Therefore, it is difficult to reuse the wafer once pasted with the protective film.
That is, in Patent Documents 1 and 2, although the protective film described has been studied from the viewpoint of adhesion to the wafer at the time of pasting and holding power to the wafer after pasting, the reworkability of the protective film No consideration has been given to.

  The present invention has been made in view of the above problems, and provides a resin film forming sheet having excellent reworkability, and a resin film forming composite sheet having the resin film forming sheet and a support. With the goal.

  The present inventors have found that a resin film forming sheet in which the surface roughness of the surface on which the silicon wafer is attached is adjusted to a predetermined value or more can solve the above problems, and have completed the present invention.

That is, the present invention provides the following [1] to [15].
[1] A sheet that is affixed to a silicon wafer to form a resin film on the silicon wafer,
A sheet for forming a resin film, wherein the surface roughness (Ra) of the surface (α) of the sheet to be bonded to the silicon wafer is 40 nm or more.
[2] The sheet for forming a resin film according to [1], including a polymer component (A) and a curable component (B).
[3] The resin film forming sheet according to [2], wherein the polymer component (A) includes an acrylic polymer (A1).
[4] The resin film forming sheet according to any one of the above [1] to [3], comprising a thermosetting component (B1).
[5] The sheet for forming a resin film according to any one of [1] to [4], including a filler (C).
[6] The resin film-forming sheet according to [5], wherein the content of the filler (C) is 10 to 80% by mass with respect to the total amount of the resin film-forming sheet.
[7] The resin film-forming sheet according to [5] or [6] above, wherein the filler (C) has an average particle diameter of 100 to 1000 nm.
[8] The resin film forming sheet according to any one of [1] to [7], which is a protective film forming sheet for forming a protective film on a silicon wafer.
[9] After the surface (α) of the resin film forming sheet was attached to a silicon wafer, the resin film formed from the resin film forming sheet was measured from the surface (β ′) opposite to the silicon wafer. The sheet for forming a resin film according to any one of [1] to [8], wherein the gloss value is 25 or more.
[10] A resin film-forming composite sheet comprising the resin film-forming sheet according to any one of [1] to [9] and a support.
[11] A resin film-forming sheet that is attached to a silicon wafer and forms a resin film on the silicon wafer, and a support (I),
Resin film formation having a structure in which the surface (α) of the resin film forming sheet on the side to be bonded to the silicon wafer and the surface (i) of the support (I) having a surface roughness of 40 nm or more are directly laminated. Composite sheet.
[12] The surface roughness (Ra) of the surface (α) of the resin film forming sheet that is exposed when the support (I) of the resin film forming composite sheet is removed is 40 nm or more, [11] The composite sheet for resin film formation according to [11].
[13] The composite sheet for forming a resin film according to [11] or [12], wherein the sheet for forming a resin film includes a thermosetting component (B1).
[14] On the surface (β) opposite to the surface (α) of the resin film-forming sheet, the second support (II) is directly laminated,
The composite sheet for resin film formation according to the above [11] or [12], wherein the resin film formation sheet contains a thermosetting component (B1).
[15] The above [14], wherein the support (II) is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer and the surface (β) of the resin film-forming sheet are directly laminated. The composite sheet for resin film formation as described.

  The resin film-forming sheet of the present invention is excellent in reworkability. Therefore, when the resin film forming sheet of the present invention is once pasted on a silicon wafer, when it is determined that the pasting is necessary, the silicon wafer is not damaged and the generation of the residue is suppressed. The film forming sheet can be peeled, and the silicon wafer after the resin film forming sheet is peeled can be reused.

  In this specification, “the reworkability of the resin film forming sheet” means that the resin film is formed on the silicon wafer without damaging the silicon wafer when peeled again after being attached to the silicon wafer. It refers to the property of being able to be peeled off without leaving a part of the sheet.

It is sectional drawing of the composite sheet for resin film formation of 1 aspect of this invention.

In the description of the present specification, the values of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of each component are values in terms of standard polystyrene measured by a gel permeation chromatography (GPC) method. Is a value measured based on the method described in Examples.
In this specification, for example, “(meth) acrylate” is used as a term indicating both “acrylate” and “methacrylate”, and the same applies to other similar terms.
Further, in this specification, “energy beam” refers to, for example, ultraviolet rays or electron beams.

[Resin film forming sheet]
The sheet for forming a resin film of the present invention is a sheet that is affixed to a silicon wafer and forms a resin film on the silicon wafer, and is a surface (α) of the sheet on the side that is affixed to the silicon wafer. The roughness (Ra) (hereinafter, also simply referred to as “surface roughness (Ra) of surface (α)”) is 40 nm or more.

Since the surface roughness (Ra) of the surface (α) of the resin film forming sheet of the present invention is 40 nm or more, the silicon wafer is not damaged even after the resin film forming sheet is once attached to the silicon wafer. And while suppressing generation | occurrence | production of a residue, the said sheet | seat for resin film formation can be peeled, and it is excellent in rework property.
On the other hand, when a resin film forming sheet having a surface (α) surface roughness (Ra) of less than 40 nm is applied to a silicon wafer and then peeled off, a residue of the resin film forming sheet is generated on the silicon wafer. There is a case. In addition, if the peeling is forcibly performed, the silicon wafer may be damaged.

  From the above viewpoint, the surface roughness (Ra) of the surface (α) of the resin film-forming sheet of the present invention is preferably 45 nm or more, more preferably 50 nm or more, still more preferably 53 nm or more, and still more preferably 55 nm or more. is there.

In addition, there is no restriction | limiting in particular as an upper limit of the surface roughness (Ra) of the surface ((alpha)) from a viewpoint of making rework property favorable.
However, the surface roughness (Ra) of the surface (α) of the resin film-forming sheet of the present invention is preferably 150 nm or less, from the viewpoint of forming a resin film-forming sheet with good adhesion to the silicon wafer. Preferably it is 100 nm or less, More preferably, it is 80 nm or less.

In the present specification, the surface roughness (Ra) of the surface (α) means a value measured by the method described in Examples.
Further, the surface roughness (Ra) of the surface (α) is appropriately set, for example, the kind of fine particle components such as fillers and colorants that can be contained in the resin film forming sheet, the average particle diameter, and the content. This can be adjusted. Moreover, it can adjust also by bonding a support body with a rough surface.

In one embodiment of the present invention, the surface roughness (Ra) of the surface (β) opposite to the surface (α) of the resin film-forming sheet is not particularly limited, but preferably 5 to 80 nm, More preferably, it is 8-60 nm, More preferably, it is 10-45 nm.
If it is in the said range, it will become easy to adjust the gloss value of the surface ((beta) ') of the resin film mentioned later formed from the sheet | seat for resin film formation high. In addition, when a silicon wafer having a resin film formed from a resin film forming sheet or a chip obtained from a silicon wafer is inspected by electromagnetic waves such as infrared rays, the electromagnetic wave permeability may be increased. it can.

From the surface (β ′) opposite to the silicon wafer of the resin film formed from the resin film forming sheet after the surface (α) of the resin film forming sheet of one embodiment of the present invention is attached to the silicon wafer The measured gloss value is preferably 25 or more, more preferably 30 or more, still more preferably 35 or more, and still more preferably 40 or more.
When the gloss value of the surface (β ′) of the resin film is 25 or more, a resin film having excellent laser printing visibility can be obtained.

In one embodiment of the present invention, the light transmittance at a wavelength of 1250 nm of the resin film-forming sheet and the resin film formed from the resin film-forming sheet is preferably 25% or more, more preferably 30% or more, and still more preferably Is 35% or more, more preferably 40% or more.
If the light transmittance is 25% or more, the infrared transmittance is good, and the infrared rays can be applied to a resin film forming sheet or a silicon wafer or chip provided with a resin film formed from the resin film forming sheet. Inspection can be performed. That is, since a crack or the like generated in the silicon wafer or the chip can be easily found through the resin film forming sheet or the resin film, the product yield can be improved.
The light transmittance at a wavelength of 1250 nm of the resin film forming sheet means a value measured by the method described in Examples.

There is no restriction | limiting in particular in the form of the sheet | seat for resin film formation of this invention, For example, forms, such as a long tape shape and a single-leaf label, may be sufficient.
The sheet for forming a resin film of the present invention may be a single layer formed from one type of composition or a multilayer formed from two or more types of compositions.
In the case where the resin film-forming sheet of one embodiment of the present invention is a multilayer body, the composition (α ′) which is the surface (α) side forming material has a surface roughness (Ra) of the surface (α). It is preferable to adjust the types and amounts of the components so that the above is in the above range.

In one embodiment of the present invention, the thickness of the resin film-forming sheet is appropriately set depending on the use, but is preferably 1 to 300 μm, more preferably 3 to 250 μm, still more preferably 5 to 200 μm, and still more preferably. Is 7 to 150 μm.
In particular, when the thickness of the silicon wafer to which the resin film forming sheet is attached is thin, the thickness of the resin film forming sheet is preferably 1 to 20 μm, more preferably 3 to 15 μm.
In addition, also when the sheet | seat for resin film formation is a multilayer body comprised from two or more layers, it is preferable that the total thickness of the said multilayer body is the said range.

<Constituent components of resin film forming sheet>
In the resin film-forming sheet of one embodiment of the present invention, the constituent components are not particularly limited as long as the surface roughness (Ra) of the surface (α) falls within the above range.
However, from the viewpoint of obtaining a sheet for forming a resin film having good sheet-like shape maintainability, the sheet for forming a resin film of one embodiment of the present invention includes a polymer component (A) and a curable component (B). It is preferable.
Further, from the viewpoint of adjusting the surface roughness (Ra) of the surface (α) to the above range, and from the viewpoint of adjusting the thermal expansion coefficient of the resin film formed from the resin film forming sheet to an appropriate range, the present invention. It is preferable that the sheet | seat for resin film formation of 1 aspect contains a filler (C).
Furthermore, the resin film-forming sheet of one embodiment of the present invention is further selected from a colorant (D), a coupling agent (E), and a general-purpose additive (F) within a range not impairing the effects of the present invention. It may contain more than seeds.
Hereinafter, the components (A) to (F) that can be constituent components of the resin film-forming sheet of one embodiment of the present invention will be described.

[Polymer component (A)]
In the present specification, the “polymer component” is a high molecular weight product obtained by a polymerization reaction and means a compound having at least one repeating unit.
By containing the polymer component (A), the resin film-forming sheet used in one embodiment of the present invention can be easily imparted with flexibility and can have good sheet-like shape maintainability. As a result, the storage elastic modulus of the resin film forming sheet can be adjusted to the above range.
The mass average molecular weight (Mw) of the polymer component (A) is preferably 20,000 or more, more preferably 20,000 to 300, from the viewpoint of adjusting the storage elastic modulus of the resulting resin film-forming sheet to the above range. It is 10,000, more preferably 100,000 to 2,000,000, and still more preferably 150,000 to 1,500,000.

  The glass transition temperature (Tg) of the acrylic polymer (A1) is preferably −40 ° C. or higher, more preferably −30 to 50 ° C., still more preferably −20 to 20 ° C., and still more preferably −15 to 0. ° C.

In the present specification, the value of the glass transition temperature of the acrylic polymer (Tg) of absolute temperature calculated by the following formula (1) (unit: K) a glass transition temperature represented by (Tg _K) It is a value converted to Celsius temperature (unit: ° C.).

[In the above formula _{(1), W 1, W} 2, W 3, W 4 ··· shows the mass fraction of the monomer components constituting the polymer component _{(mass%), Tg 1, Tg 2} , Tg ₃ , Tg ₄ ... Indicate the glass transition temperature (unit: K) of the homopolymer of each monomer component constituting the polymer component. ]

  In one aspect of the present invention, the content of the polymer component (A) in the resin film-forming sheet is preferably 5 to 60% by mass with respect to the total amount (100% by mass) of the resin film-forming sheet. Preferably it is 8-50 mass%, More preferably, it is 10-45 mass%, More preferably, it is 15-40 mass%.

In the present specification, “content of component (A) with respect to the total amount of the resin film-forming sheet” means “component (A) with respect to the total amount of active ingredients of the composition that is a material for forming the resin film-forming sheet”. It is the same as “content”. The same applies to the contents of other components described below.
Furthermore, the above “active ingredient” means a component excluding substances that do not directly or indirectly affect the physical properties of the formed sheet, such as a solvent in the composition, specifically, , Meaning components other than solvents such as water and organic solvents.

The polymer component (A) preferably contains an acrylic polymer (A1).
The polymer component (A) may contain a non-acrylic polymer (A2) together with the acrylic polymer (A1).
These polymer components may be used alone or in combination of two or more.

  In one aspect of the present invention, the content of the acrylic polymer (A1) with respect to the total amount (100% by mass) of the polymer component (A) contained in the resin film-forming sheet is preferably 50 to 100% by mass. %, More preferably, it is 60-100 mass%, More preferably, it is 70-100 mass%, More preferably, it is 80-100 mass%.

(Acrylic polymer (A1))
The weight average molecular weight (Mw) of the acrylic polymer (A1) provides flexibility and film-forming property to the resin film-forming sheet, and adjusts the storage elastic modulus of the resin film-forming sheet to the above range. From 20,000 to 3,000,000, more preferably from 100,000 to 1,500,000, still more preferably from 150,000 to 1,200,000, still more preferably from 250,000 to 1,000,000.

  Examples of the acrylic polymer (A1) include polymers having an alkyl (meth) acrylate as a main component, and specifically, a configuration derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms. An acrylic polymer containing the unit (a1) is preferable, and an acrylic copolymer containing another structural unit (a2) other than the structural unit (a1) may be used.

In addition, you may use an acrylic polymer (A1) individually or in combination of 2 or more types.
Further, when the acrylic polymer (A1) is a copolymer, the form of the copolymer may be any of a block copolymer, a random copolymer, an alternating copolymer, and a graft copolymer. Good.

(Structural unit (a1))
The number of carbon atoms of the alkyl group of the alkyl (meth) acrylate constituting the structural unit (a1) is preferably 1 to 18 from the viewpoint of imparting flexibility and film forming property to the resin film forming sheet. Preferably it is 1-12, More preferably, it is 1-8.

Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and isooctyl ( Examples include meth) acrylate, n-octyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and the like.
In addition, you may use these alkyl (meth) acrylates individually or in combination of 2 or more types.

Among these, alkyl (meth) acrylates having an alkyl group having 1 to 3 carbon atoms are preferable, and methyl (meth) acrylate is more preferable.
The content of the structural unit (a11) derived from the alkyl (meth) acrylate having an alkyl group having 1 to 3 carbon atoms in the acrylic polymer (A1) is the total structural unit of the acrylic polymer (A1) (100 % By mass) is preferably 5 to 80% by mass, more preferably 15 to 70% by mass, and still more preferably 25 to 60% by mass.

Moreover, the alkyl (meth) acrylate which has a C4-C12 alkyl group is preferable, and a butyl (meth) acrylate is more preferable.
The content of the structural unit (a12) derived from the alkyl (meth) acrylate having an alkyl group having 4 to 12 carbon atoms in the acrylic polymer (A1) is the total structural unit of the acrylic polymer (A1) (100 % By mass) is preferably 5 to 80% by mass, more preferably 15 to 70% by mass, and still more preferably 20 to 60% by mass.

The acrylic polymer (A1) used in one embodiment of the present invention is preferably an acrylic copolymer that includes both the structural unit (a11) and the structural unit (a12).
The content ratio [(a11) / (a12)] (mass ratio) between the structural unit (a11) and the structural unit (a12) of the acrylic copolymer is preferably 20/80 to 95/5, more preferably. Is 30/70 to 90/10, more preferably 40/60 to 85/15, and still more preferably 52/48 to 75/25.

  The content of the structural unit (a1) in the acrylic polymer (A1) is preferably 50% by mass or more, more preferably 50% with respect to the total structural unit (100% by mass) of the acrylic polymer (A1). It is -99 mass%, More preferably, it is 55-98 mass%, More preferably, it is 60-97 mass%.

(Structural unit (a2))
The acrylic polymer (A1) used in one embodiment of the present invention may have another structural unit (a2) other than the structural unit (a1) as long as the effects of the present invention are not impaired.
Examples of monomers constituting the structural unit (a2) include functional group-containing monomers such as hydroxy group-containing monomers, carboxy group-containing monomers, and epoxy group-containing monomers; vinyl ester monomers such as vinyl acetate and vinyl propionate; ethylene, Examples thereof include olefin monomers such as propylene and isobutylene; aromatic vinyl monomers such as styrene, methylstyrene and vinyltoluene; diene monomers such as butadiene and isoprene; and nitrile monomers such as (meth) acrylonitrile.
Among these, a functional group-containing monomer is preferable, and at least one selected from a hydroxy group-containing monomer and an epoxy group-containing monomer is preferable.

Examples of the hydroxy-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 3-hydroxybutyl (meth) ) Hydroxyalkyl (meth) acrylates such as acrylate and 4-hydroxybutyl (meth) acrylate; and unsaturated alcohols such as vinyl alcohol and allyl alcohol.
Among these, 2-hydroxyethyl (meth) acrylate is preferable.

  Examples of the carboxy group-containing monomer include (meth) acrylic acid, maleic acid, fumaric acid, and itaconic acid.

Examples of the epoxy group-containing monomer include glycidyl (meth) acrylate, β-methylglycidyl (meth) acrylate, (3,4-epoxycyclohexyl) methyl (meth) acrylate, and 3-epoxycyclo-2-hydroxypropyl (meth). And epoxy group-containing (meth) acrylic acid esters such as acrylate; non-acrylic epoxy group-containing monomers such as glycidyl crotonate and allyl glycidyl ether; and the like.
An acrylic polymer having a structural unit derived from an epoxy group-containing monomer and having an Mw of 20,000 or more has thermosetting properties, but is not a curable component (B) but a polymer component (A). It shall be included in the concept of

The acrylic polymer (A1) used in one embodiment of the present invention preferably includes a structural unit (a21) derived from a hydroxy group-containing monomer.
The content of the structural unit (a21) derived from the hydroxy group-containing monomer in the acrylic polymer (A1) is preferably 1 to 1 with respect to the total structural unit (100% by mass) of the acrylic polymer (A1). 40 mass%, More preferably, it is 5-30 mass%, More preferably, it is 8-25 mass%, More preferably, it is 10-20 mass%.

In addition, the acrylic polymer (A1) used in one embodiment of the present invention preferably includes a structural unit (a22) derived from an epoxy group-containing monomer.
The content of the structural unit (a22) derived from the epoxy group-containing monomer in the acrylic polymer (A1) is preferably from 1 to the total structural unit (100% by mass) of the acrylic polymer (A1). It is 40 mass%, More preferably, it is 5-30 mass%, More preferably, it is 8-25 mass%.

Moreover, when using an epoxy-type thermosetting component as a curable component (B) mentioned later, since the epoxy group in an epoxy-type thermosetting component will react, an acrylic polymer (A1) It is preferable that the content of the structural unit derived from the carboxyl group-containing monomer is small.
When an epoxy thermosetting component is used as the curable component (B), the content of the structural unit derived from the carboxy group-containing monomer is based on the total structural unit (100% by mass) of the acrylic polymer (A1). Preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%, More preferably, it is 0-2 mass%, More preferably, it is 0 mass%.

  The content of the structural unit (a2) in the acrylic polymer (A1) is preferably 1 to 50% by mass, more preferably based on the total structural unit (100% by mass) of the acrylic polymer (A1). It is 2-45 mass%, More preferably, it is 3-40 mass%.

(Non-acrylic resin (A2))
The resin film-forming sheet of one embodiment of the present invention may contain a non-acrylic polymer (A2) as a polymer component other than the acrylic polymer (A1) as necessary.
Examples of the non-acrylic polymer (A2) include polyester, phenoxy resin, polycarbonate, polyether, polyurethane, polysiloxane, rubber polymer, and the like.
These non-acrylic polymers (A2) may be used alone or in combination of two or more.

  The mass average molecular weight (Mw) of the non-acrylic polymer (A2) is preferably 20,000 or more, more preferably 20,000 to 100,000, and still more preferably 20,000 to 80,000.

[Curable component (B)]
The curable component (B) serves to cure the resin film-forming sheet to form a hard resin film, and is a compound having a mass average molecular weight (Mw) of less than 20,000.
The resin film forming sheet used in the present invention preferably contains at least one of a thermosetting component (B1) and an energy ray curable component (B2) as the curable component (B), and sufficiently proceeds with the curing reaction. It is more preferable that the thermosetting component (B1) is included at least from the viewpoint of reducing the cost and reducing the cost.
The thermosetting component (B1) preferably contains at least a compound having a functional group that reacts by heating.
The energy ray-curable component (B2) contains a compound (B21) having a functional group that reacts by irradiation with energy rays, and is polymerized and cured when irradiated with energy rays.
Curing is realized by the functional groups of these curable components reacting to form a three-dimensional network structure.
The mass average molecular weight (Mw) of the curable component (B) is used in combination with the component (A), thereby suppressing the viscosity of the composition forming the resin film-forming sheet and improving the handleability. Therefore, it is preferably less than 20,000, more preferably 10,000 or less, and still more preferably 100 to 10,000.

(Thermosetting component (B1))
As the thermosetting component (B1), an epoxy thermosetting component is preferable.
As the epoxy thermosetting component, it is preferable to use a combination of a thermosetting agent (B12) together with a compound (B11) having an epoxy group.

Examples of the compound (B11) having an epoxy group (hereinafter also referred to as “epoxy compound (B11)”) include novolaks such as polyfunctional epoxy resins, bisphenol A diglycidyl ether and hydrogenated products thereof, and cresol novolac epoxy resins. And epoxy compounds having two or more functional groups in the molecule, such as type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, and phenylene skeleton type epoxy resin.
These epoxy compounds (B11) may be used alone or in combination of two or more.
Among these, it is preferable to include at least one selected from a novolac type epoxy resin and a biphenyl type epoxy resin.

In one embodiment of the present invention, the epoxy compound (B11) preferably includes an epoxy compound that is liquid at 25 ° C. (hereinafter also referred to as “liquid epoxy compound”).
When the epoxy compound (B11) contains the liquid epoxy compound, the value of the elongation at break of the resin film-forming sheet can be increased, and the resin film-forming sheet excellent in reworkability can be obtained.
In one embodiment of the present invention, from the above viewpoint, the content of the liquid epoxy compound is preferably 10% by mass or more with respect to the total amount (100% by mass) of the epoxy compound (B11) in the resin film-forming sheet. Preferably it is 15 mass% or more, More preferably, it is 30 mass% or more, More preferably, it is 40 mass% or more.
On the other hand, from the viewpoint of improving the reliability of the chip with a resin film produced using the resin film forming sheet, the content of the liquid epoxy compound is the total amount of the epoxy compound (B11) in the resin film forming sheet (100% by mass). ) Is preferably 90% by mass or less, more preferably 80% by mass or less, still more preferably 75% by mass or less, and still more preferably 70% by mass or less.
In the present specification, the “liquid epoxy compound” means an epoxy compound having a viscosity at 25 ° C. of 40 Pa · s or less. Moreover, in this specification, the viscosity at 25 degreeC of an epoxy compound is the value measured at 25 degreeC using the E-type viscosity meter according to JISZ8803.

  The content of the epoxy compound (B11) is preferably 1 to 500 parts by mass, more preferably 3 to 300 parts by mass, still more preferably 5 to 150 parts by mass, and still more preferably 100 parts by mass of the component (A). Is 10 to 100 parts by mass.

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

Examples of the phenol-based thermosetting agent having a phenolic hydroxyl group include polyfunctional phenol resins, biphenols, novolac-type phenol resins, dicyclopentadiene-type phenol resins, zyloc-type phenol resins, and aralkyl-type phenol resins.
Examples of the amine-based thermosetting agent having an amino group include dicyandiamide (DICY).
These thermosetting agents (B12) may be used alone or in combination of two or more.
Among these, it is preferable that an amine thermosetting agent is included.

  The content of the thermosetting agent (B12) is preferably 0.1 to 500 parts by mass, more preferably 0.5 to 300 parts by mass, and still more preferably 1 to 200 parts per 100 parts by mass of the epoxy compound (B11). Part by mass.

(Curing accelerator (B13))
The sheet | seat for resin film formation of 1 aspect of this invention may contain a hardening accelerator (B13) from a viewpoint of adjusting the cure rate by the heating of the said sheet | seat.
The curing accelerator (B13) is preferably used in combination with the epoxy compound (B11) as the thermosetting component (B1).

Examples of the curing accelerator (B13) include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, Imidazoles such as 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole; tributylphosphine, diphenylphosphine, triphenylphosphine, etc. Organic phosphines; tetraphenyl boron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylborate.
These curing accelerators (B13) may be used alone or in combination of two or more.

  The content of the curing accelerator (B13) is 100 parts by mass of the total amount of the epoxy compound (B11) and the thermosetting agent (B12) from the viewpoint of improving the adhesiveness of the resin film formed from the resin film forming sheet. On the other hand, it is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 6 parts by mass, and still more preferably 0.3 to 4 parts by mass.

(Energy ray curable component (B2))
As the energy ray-curable component (B2), the compound (B21) having a functional group that reacts by irradiation with energy rays may be used alone, but the photopolymerization initiator (B22) is combined with the compound (B21). It is preferable to use it. The energy ray curable component (B2) is preferably one that is cured by ultraviolet rays.

(Compound (B21) having a functional group that reacts upon irradiation with energy rays)
Examples of the compound (B21) having a functional group that reacts upon irradiation with energy rays (hereinafter, also referred to as “energy ray-reactive compound (B21)”) include trimethylolpropane tri (meth) acrylate and pentaerythritol tri (meth). Acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, 1,6-hexanediol di ( Examples include meth) acrylate, oligoester (meth) acrylate, urethane (meth) acrylate oligomer, epoxy (meth) acrylate, polyether (meth) acrylate, and itaconic acid oligomer.
These energy beam reactive compounds (B21) may be used alone or in combination of two or more.
In addition, the mass average molecular weight (Mw) of the energy ray reactive compound (B21) is preferably 100 to 30,000, more preferably 200 to 20,000, and still more preferably 300 to 10,000.

  The content of the energy ray reactive compound (B21) is preferably 1 to 1500 parts by mass, more preferably 3 to 1200 parts by mass, and still more preferably 5 to 1000 parts by mass with respect to 100 parts by mass of the component (A). is there.

(Photopolymerization initiator (B22))
By using the photopolymerization initiator (B22) together with the energy ray-reactive compound (B21) described above, the curing of the resin film forming sheet is advanced even if the polymerization curing time is shortened and the amount of light irradiation is small. be able to.

Examples of the photopolymerization initiator (B22) include benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, thioxanthone compounds, peroxide compounds, and the like.
More specific photopolymerization initiators include, for example, 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile. , Dibenzyl, diacetyl, β-chloranthraquinone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and the like.
These photopolymerization initiators may be used alone or in combination of two or more.

  The content of the photopolymerization initiator (B22) is sufficiently advanced with respect to 100 parts by mass of the energy ray-reactive compound (B21) from the viewpoint of sufficiently promoting the curing reaction of the resin film-forming sheet and suppressing the formation of residues. Preferably, it is 0.1-10 mass parts, More preferably, it is 0.5-8 mass parts, More preferably, it is 1-5 mass parts.

In one aspect of the present invention, the content of the curable component (B) in the resin film-forming sheet is preferably 5 to 50% by mass with respect to the total amount (100% by mass) of the resin film-forming sheet. Preferably it is 8-40 mass%, More preferably, it is 10-30 mass%, More preferably, it is 12-25 mass%.
In addition, said "content of a sclerosing | hardenable component (B)" is the thermosetting component (B1) containing the above-mentioned epoxy compound (B11), a thermosetting agent (B12), and a hardening accelerator (B13), and The total content of the energy ray-curable component (B2) including the energy ray-reactive compound (B21) and the photopolymerization initiator (B22).

[Filler (C)]
The sheet for forming a resin film of one embodiment of the present invention preferably contains a filler (C).
By including the filler (C), it becomes easy to adjust the surface roughness (Ra) of the surface (α) of the resin film-forming sheet to the above range.
In addition, the resin film forming sheet containing the filler (C) can adjust the thermal expansion coefficient of the resin film to be formed within an appropriate range, and optimize the thermal expansion coefficient of the chip with the resin film. Thus, the reliability of the semiconductor device in which the chip is incorporated can be improved. It is also possible to reduce the moisture absorption rate of the resin film formed from the resin film forming sheet.

Fillers (C) include organic fillers such as polymethylmethacrylate filler and rubber particles, and powders such as silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride, and the like. Examples thereof include inorganic fillers such as spherical beads, single crystal fibers, and glass fibers.
These fillers (C) may be used alone or in combination of two or more.
Among these, when the resin film forming sheet is thermosetting, an inorganic filler is preferable, and silica or alumina is more preferable from the viewpoint of excellent heat resistance.

In one embodiment of the present invention, the average particle diameter of the filler (C) is preferably from the viewpoint of easily adjusting the surface roughness (Ra) of the surface (α) of the formed resin film-forming sheet to the above range. Is 3 to 20 μm, more preferably 5 to 15 μm.
If the average particle size is a filler in the above range, the surface roughness (Ra) of the surface (α) of the resin film forming sheet to be formed is the above even when the content of the filler (C) is relatively small. Can be easily adjusted to the range.

However, the filler (C) having a relatively small average particle diameter is used by adding a relatively large content of the filler (C) or by configuring the composite sheet for resin film formation described later. Even in this case, the surface roughness (Ra) of the surface (α) of the formed resin film-forming sheet can be adjusted to the above range.
In the above case, the average particle diameter of the filler (C) is preferably 100 to 1000 nm, more preferably 200 to 900 nm, still more preferably 200 to 800 nm, still more preferably 300 to 750 nm, and still more preferably 400. ~ 700 nm.
If the average particle diameter of the filler (C) is 100 nm or more, the surface roughness (Ra) of the surface (α) of the resin film-forming sheet is adjusted to the above range by adjusting the content of the filler (C). Easy to adjust.

Moreover, if the average particle diameter of a filler (C) is 1000 nm or less, there exist the following advantages (1)-(4).
(1) After the surface (α) of the resin film forming sheet is attached to a silicon wafer, the gloss measured from the surface (β ′) opposite to the silicon wafer of the resin film formed from the resin film forming sheet The value can be increased.
(2) It becomes easy to improve the transparency of electromagnetic waves such as infrared rays of the resin film forming sheet and the resin layer. As a result, when performing inspection using electromagnetic waves on a silicon wafer or chip having a resin film forming sheet and a resin layer, the electromagnetic wave is highly permeable, so the efficiency of the inspection work is improved.
(3) In the process of irradiating the resin film forming sheet and the silicon wafer having the resin film with a laser, it is easy to avoid the problem that the laser diffuses due to the presence of the resin film forming sheet and the resin film.
(4) For example, when a resin film forming sheet having a thickness of 20 μm or less is manufactured, in the coating process of the composition that is a material for forming the resin film forming sheet, the coating caused by the filler having a large particle diameter It is easy to avoid problems such as film formation defects.

When the resin film forming sheet of one embodiment of the present invention is a multilayer formed from two or more compositions, the composition that is a forming material on the surface (α) side of the resin film forming sheet is: It is preferable to blend the filler (C) having an average particle diameter in the above range to adjust the surface roughness (Ra) of the surface (α).
On the other hand, the composition which is the forming material on the surface (β) side improves the gloss value measured from the surface (β ′) opposite to the silicon wafer of the resin film formed from the resin film forming sheet. From the viewpoint, it is preferable to blend a filler (C ′) having a small average particle diameter different from the above range.
The average particle diameter of the filler (C ′) is usually 1 to 400 nm, preferably 1 to 250 nm, more preferably 1 to 100 nm.

  In addition, in this specification, the average particle diameter of filler (C) and (C ') means the value measured using the dynamic light scattering type particle size distribution analyzer (Nanotrack Wave-UT151, Nikkiso Co., Ltd. make). To do.

  In one aspect of the present invention, the content of the filler (C) in the resin film forming sheet is a viewpoint of adjusting the surface roughness (Ra) of the surface (α) of the resin film forming sheet to the above range, and From the viewpoint of improving the reliability of the chip with a resin film produced using the resin film forming sheet, it is preferably 10 to 80% by mass with respect to the total amount (100% by mass) of the resin film forming sheet. More preferably, it is 20-70 mass%, More preferably, it is 30-65 mass%, More preferably, it is 40-60 mass%.

  In one embodiment of the present invention, the total content of the polymer film (A), the curable component (B), and the filler (C) in the resin film-forming sheet is the total amount of the resin film-forming sheet (100 % By mass) is preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and still more preferably 90% by mass or more.

[Colorant (D)]
The resin film-forming sheet of one embodiment of the present invention may further contain a colorant (D).
Grinding marks generated during grinding of a semiconductor wafer when a semiconductor chip having a resin film formed from the resin film forming sheet is incorporated into a device by containing the colorant (D) in the resin film forming sheet. Can be made difficult to see, and the appearance of the semiconductor chip can be adjusted.

As the colorant (D), organic or inorganic pigments and dyes can be used.
As the dye, for example, any dye such as an acid dye, a reactive dye, a direct dye, a disperse dye, and a cationic dye can be used.
The pigment is not particularly limited and can be appropriately selected from known pigments. For example, phthalocyanine blue pigment, isoindolinone yellow pigment, diketopyrrolopyrrole red pigment, carbon black And black pigments such as iron oxide, manganese dioxide, aniline black, and activated carbon.
These colorants (D) may be used alone or in combination of two or more.
By using a mixture of phthalocyanine blue pigment, isoindolinone yellow pigment, and diketopyrrolopyrrole red pigment, the transmittance of light in the infrared region is improved and the transmittance of visible light is low. It is easy to obtain a resin film.

  The average particle diameter of the colorant (D) is preferably 400 nm or less, more preferably 300 nm or less, still more preferably 200 nm or less, still more preferably 100 nm or less, and preferably 10 nm or more, more preferably 20 nm or more. It is.

  In one embodiment of the present invention, the content of the colorant (D) in the resin film-forming sheet is preferably 0.01 to 20% by mass with respect to the total amount (100% by mass) of the resin film-forming sheet. More preferably, it is 0.05-15 mass%, More preferably, it is 0.1-10 mass%, More preferably, it is 0.15-5 mass%.

[Coupling agent (E)]
The resin film-forming sheet of one embodiment of the present invention may further contain a coupling agent (E).
By including a coupling agent (E), water resistance can also be improved without impairing the heat resistance of the resin film formed from the obtained resin film forming sheet. Moreover, it contributes to the improvement of end part adhesion after sticking with a silicon wafer.

As a coupling agent (E), the compound which reacts with the functional group which a component (A) or a component (B) has is preferable, and a silane coupling agent is more preferable.
Examples of the silane coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- (methacryloxy). Propyl) trimethoxysilane, γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N -Phenyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltri Methoxysilane , Methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolesilane and the like.
These coupling agents (E) may be used alone or in combination of two or more.

As the coupling agent (E), an oligomer type coupling agent is preferable.
The molecular weight of the coupling agent (E) including the oligomer type coupling agent is preferably 100 to 15000, more preferably 150 to 10,000, still more preferably 200 to 5000, still more preferably 250 to 3000, and still more. Preferably it is 350-2000.

  In one aspect of the present invention, the content of the coupling agent (E) in the resin film-forming sheet is preferably 0.01 to 3.0 with respect to the total amount (100% by mass) of the resin film-forming sheet. It is 0.03 to 1.5 mass%, More preferably, it is 0.05 to 0.8 mass%, More preferably, it is 0.1 to 0.3 mass%.

[General-purpose additive (F)]
The resin film-forming sheet used in one embodiment of the present invention may contain a general-purpose additive (F) as necessary, in addition to the above-described components, as long as the effects of the present invention are not impaired.
Examples of the general-purpose additive (F) include a crosslinking agent, a plasticizer, a leveling agent, an antistatic agent, an antioxidant, an ion scavenger, a gettering agent, and a chain transfer agent.

  The content of each of these general-purpose additives (F) in the resin film-forming sheet of one embodiment of the present invention is preferably 0 to 10 mass with respect to the total amount (100% by mass) of the resin film-forming sheet. %, More preferably, it is 0-5 mass%, More preferably, it is 0-2 mass%.

<Method for Producing Resin Film Forming Sheet>
There is no restriction | limiting in particular as a manufacturing method of the sheet | seat for resin film formation of this invention, It can manufacture by a well-known method.
For example, after preparing a resin film-forming composition containing the above-described components, which is a forming material for the resin film-forming sheet, an organic solvent is appropriately added and diluted to obtain a solution of the resin film-forming composition. And the solution of the said resin film formation composition is apply | coated by the well-known coating method on the below-mentioned support body, a coating film is formed, and this coating film is dried, and the sheet | seat for resin film formation is manufactured. be able to.

In addition, from the viewpoint of adjusting the surface roughness (Ra) of the surface (α) of the obtained resin film-forming sheet to the above range, as a method for producing the resin film-forming sheet, a resin film-forming sheet forming material is used. A composition for forming a resin film is applied on the surface of a support having a surface having a surface roughness (Ra) of 40 nm or more to form a coating film, and the coating film is dried. preferable.
The resin film-forming composition may be diluted by appropriately adding a solvent to form a resin film-forming composition solution.
Further, the surface roughness (Ra) of the surface of the support is preferably 40 nm or more, more preferably 70 nm or more, still more preferably 100 nm or more, still more preferably 200 nm or more, and still more preferably 300 nm or more. Also, it is preferably 1000 nm or less, more preferably 800 nm or less, and still more preferably 500 nm or less.

  In addition, when the resin film-forming sheet according to one aspect of the present invention is a multilayer body, the resin film-forming sheet may be produced, for example, on two or more supports, respectively. The manufacturing method which has the process of apply | coating the solution of an object, forming a coating film, bonding the said coating film together, laminating | stacking a coating film, and drying may be sufficient.

Examples of the organic solvent used for preparing the resin film-forming composition solution include toluene, ethyl acetate, methyl ethyl ketone, and the like.
The solid content concentration of the solution of the resin film forming composition when an organic solvent is blended is preferably 10 to 80% by mass, more preferably 20 to 70% by mass, and still more preferably 30 to 65% by mass.
Examples of the coating method include spin coating, spray coating, bar coating, knife coating, roll coating, roll knife coating, blade coating, die coating, and gravure coating.

<Use of resin film forming sheet>
The sheet for forming a resin film of one embodiment of the present invention can be attached to the back surface of a work such as a semiconductor wafer for chip semiconductors such as a face-down chip or a semiconductor chip to form a resin film on the work. This resin film has a function as a protective film for protecting the back surface of a workpiece such as a semiconductor wafer or a semiconductor chip. For example, when affixed to a semiconductor wafer, the resin film has a function of reinforcing the wafer, so that damage to the wafer can be prevented.
That is, the resin film forming sheet of one embodiment of the present invention is preferably a protective film forming sheet for forming a protective film on a silicon wafer.

Further, the resin film formed from the resin film-forming sheet of one embodiment of the present invention can also provide a function as an adhesive sheet. That is, when the resin film formed using the resin film forming sheet of one embodiment of the present invention has a function as an adhesive film, the chip having the resin film may be a die pad part or another semiconductor chip. It can be adhered on the member (on the chip mounting portion), and can contribute to the improvement of productivity for manufacturing a semiconductor device.
That is, the resin film forming sheet of one embodiment of the present invention can be an adhesive film forming sheet for forming an adhesive film on a silicon wafer.

[Configuration of Composite Sheet for Forming Resin Film]
The composite sheet for forming a resin film of the present invention (hereinafter also simply referred to as “composite sheet”) has the sheet for forming a resin film of the present invention and a support.
In addition, there is no restriction | limiting in particular about the form of the composite sheet of 1 aspect of this invention, For example, forms, such as a long tape shape and a single-leaf label, may be sufficient.
FIG. 1 is a cross-sectional view of a composite sheet for forming a resin film of one embodiment of the present invention.
As a composite sheet of one embodiment of the present invention, a composite sheet 1a having a configuration in which a resin film forming sheet 10 is directly laminated on a support 11 as shown in FIG.
The shape of the resin film forming sheet 10 of the composite sheet of one embodiment of the present invention may be any shape that is substantially the same as the silicon wafer that is the adherend or can include the shape of the silicon wafer.

  In the composite sheet 1a of FIG. 1A, the support 11 and the resin film forming sheet 10 have substantially the same shape, but as shown in FIG. The composite sheet 1b whose shape is smaller than the shape of the support 11 may be used.

Moreover, as a composite sheet of 1 aspect of this invention, as shown in FIG.1 (c), the composite sheet 1c which has the ring-shaped jig | tool adhesion layer 12 is mentioned.
The ring-shaped jig adhesive layer 12 is provided for the purpose of improving the adhesive force to a jig such as a ring frame, and has a base material (core material). Or it can form from an adhesive.
In addition, although the composite sheet 1c shown in FIG. 1C shows a configuration in which a jig adhesive layer 12 is further provided to the composite sheet 1a shown in FIG. Examples of the composite sheet include a composite sheet having a configuration in which a jig adhesive layer 12 is provided on the surface of the support 11 of the composite sheet 1b in FIG.

The composite sheet of one embodiment of the present invention may be a composite sheet 1d having a configuration in which a resin film forming sheet 10 is sandwiched between two supports 11, 11 ′ as shown in FIG.
Similar to the structure of the composite sheet 1d, a support other than the support 11 may be provided on the surface of the resin film forming sheet 10 exposed from the composite sheet 1b in FIG. .
Similarly, a support different from the support 11 may be provided on the surface of the resin film forming sheet 10 and the surface of the jig bonding layer 12 of the composite sheet 1c shown in FIG. .

<Support>
The support of the composite sheet of one embodiment of the present invention is a release sheet for preventing adhesion of dust or the like on the surface of the resin film forming sheet, or for protecting the surface of the resin film forming sheet in a dicing process or the like. It plays the role of a dicing sheet or the like.

The support used in the present invention preferably has a structure having a resin film.
Examples of the resin film include polyethylene films such as low density polyethylene (LDPE) films and linear low density polyethylene (LLDPE) films, ethylene / propylene copolymer films, polypropylene films, polybutene films, polybutadiene films, and polymethylpentene. Film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, polybutylene terephthalate film, polyurethane film, ethylene / vinyl acetate copolymer film, ionomer resin film, ethylene / (meth) acrylic Acid copolymer film, ethylene / (meth) acrylate copolymer film, polystyrene film, polycarbonate film , Polyimide films, fluororesin films and the like.
The base material used in one embodiment of the present invention may be a single-layer film made of one type of resin film or a laminated film in which two or more types of resin films are laminated.

The resin film may be a crosslinked film.
Moreover, what colored these resin films, or what gave printing etc. can be used.
Furthermore, the resin film may be a sheet formed by extrusion forming a thermoplastic resin, or may be a stretched sheet, and a sheet formed by thinning and curing a curable resin by a predetermined means. May be used.

Among these resin films, a base material including a polypropylene film is preferable from the viewpoint that it has excellent heat resistance and has an appropriate flexibility so that it has expandability and pickup property is easily maintained.
In addition, as a structure of the base material containing a polypropylene film, the single layer structure which consists only of a polypropylene film may be sufficient, and the multilayer structure which consists of a polypropylene film and another resin film may be sufficient.
When the resin film forming sheet is thermosetting, the resin film constituting the base material has heat resistance, so that damage to the base material due to heat can be suppressed, and occurrence of problems in the manufacturing process of the semiconductor device can be suppressed. .

  When the support is used as a release sheet for preventing dust and the like from adhering to the surface of the resin film-forming sheet, the support can be easily peeled off from the resin film-forming sheet at the time of pasting with a silicon wafer or at the dicing process A resin film is preferred.

Moreover, as the said support body, you may use the resin film which gave the peeling process to the surface of the above-mentioned resin film.
As a method for the release treatment, a method of providing a release film formed from a release agent on the surface of the resin film is preferable.
Examples of the release agent include release agents containing resins selected from acrylic resins, alkyd resins, silicone resins, fluorine resins, unsaturated polyester resins, polyolefin resins, wax resins, and the like. .

When the support is used as a dicing sheet for fixing the resin film forming sheet in a dicing step or the like, the support is preferably a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed from a pressure-sensitive adhesive on the resin film. .
The adhesive resin contained in the adhesive includes, for example, an acrylic resin, a urethane resin, a rubber resin, a silicone resin, a vinyl ether resin, etc., when focusing on the structure of the adhesive resin. When attention is paid, for example, an energy beam curable resin and the like can be mentioned.
In one embodiment of the present invention, a pressure-sensitive adhesive containing an energy ray curable resin is preferable from the viewpoint of improving pickup properties.

The thickness of the support is appropriately selected depending on the application, but is preferably 10 to 500 μm, more preferably 20 to 350 μm, and still more preferably 30 to 200 μm.
The thickness of the support includes not only the thickness of the resin film constituting the support, but also the thickness of the pressure-sensitive adhesive layer or release film when it has an adhesive layer or release film.

<Jig adhesive layer>
The jig adhesive layer can be formed from a double-sided pressure-sensitive adhesive sheet having a base material (core material) or a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive.
As the said base material (core material), the resin film which can be used as the above-mentioned base material is mentioned, A polypropylene film is preferable.
Examples of the pressure-sensitive adhesive include acrylic resins, urethane resins, rubber resins, silicone resins, vinyl ether resins, and the like.
The thickness of the jig adhesive layer is preferably 1 to 80 μm, more preferably 5 to 60 μm, and still more preferably 10 to 40 μm.

[Composite sheet for forming a resin film of another embodiment of the present invention]
As another embodiment of the present invention, the following composite sheet for forming a resin film (hereinafter, also referred to as “composite sheet (1)”) may be mentioned.
The composite sheet (1) which is one embodiment of the present invention is a sheet attached to a silicon wafer and having a resin film forming sheet and a support (I) for forming a resin film on the silicon wafer. It is the same structure as the composite sheet 1a-1d shown in the above-mentioned FIG.
However, in the composite sheet (1), the surface (α) of the resin film forming sheet on the side to be attached to the silicon wafer and the surface (i) of the support (I) having a surface roughness of 40 nm or more are directly It has a laminated structure.
The surface (α) of the resin film-forming sheet that appears when the support (I) is removed from the composite sheet (1) has a surface roughness formed on the surface (i) of the support (I). The surface roughness (Ra) is 40 nm or more so that the surface roughness (Ra) is the same or less than the surface roughness (Ra) formed on the surface (i) of the support (I). , Considered to be migrated.
Therefore, the surface roughness (Ra) of the surface (α) of the resin film-forming sheet after removing the support (I) from the composite sheet (1) is not less than a predetermined value such that the effect of improving the reworkability is exhibited. It is considered that there is an effect of improving the reworkability similarly to the above-described resin film forming sheet of the present invention.

The resin film forming sheet included in the composite sheet (1) which is one embodiment of the present invention preferably has thermosetting properties.
If the resin film forming sheet has thermosetting properties, the uneven shape of the surface (α) of the resin film forming sheet is easily deformed in the heating step after the resin film forming sheet is attached to the silicon wafer. It is difficult for voids due to the uneven shape of the surface (α) of the resin film forming sheet to occur at the interface with the silicon wafer. As a result, in the resin film formed on the silicon wafer, the scattering of the light beam caused by the gap can be suppressed, and the inspection of the silicon wafer having the resin film and the inspection of the chip by visual observation or electromagnetic waves such as infrared rays. Becomes easy.
The sheet for forming a resin film included in the composite sheet (1) which is one embodiment of the present invention preferably contains the above-described thermosetting component (B1) from the viewpoint of imparting thermosetting properties.

  The surface roughness (Ra) of the resin film-forming sheet after removing the support (I) of the composite sheet (1) is preferably 40 nm or more, more preferably 45 nm or more, still more preferably 50 nm or more, more More preferably, it is 53 nm or more, More preferably, it is 55 nm or more, Preferably it is 200 nm or less, More preferably, it is 150 nm or less, More preferably, it is 100 nm or less.

  Further, the surface roughness (Ra) of the surface (i) of the support (I) is preferably 40 nm or more, more preferably 70 nm or more, still more preferably 100 nm or more, still more preferably 200 nm or more, and still more preferably. It is 300 nm or more, preferably 1000 nm or less, more preferably 800 nm or less, and still more preferably 500 nm or less.

  The support (I) of the composite sheet (1) is not particularly limited as long as it is a surface-treated and peelable support so that the surface roughness (Ra) is in the above range, but is not limited to paper or resin film. From the viewpoint of reducing the possibility of generation of dust, it is more preferable that the resin film is made of a resin film.

Examples of the method for adjusting the surface roughness (Ra) of the surface (i) of the support (I) include a method of containing a filler in the resin film constituting the support (I) and a filler. Examples thereof include a method of providing a release film formed from a release agent.
Further, when the support (I) is composed of a resin film produced by melt extrusion, the molten resin is injected onto a roll having a rough surface shape so that the surface roughness (Ra) is in the above range. It is good also as the adjusted resin film.
In addition, the surface roughness (Ra) of the surface (i) of the support (I) is adjusted by using a material whose surface is rough due to its properties, such as paper or nonwoven fabric, as the forming material of the support (I). May be.

Further, the composite sheet (1) is further provided with a second support on the surface (β) opposite to the surface (α) of the resin film-forming sheet, like the composite sheet 1d shown in FIG. A composite sheet having a structure in which the body (II) is directly laminated may be used.
It is preferable that the resin film-forming sheet of the composite sheet has thermosetting properties. Therefore, it is preferable that the said resin film formation sheet contains the above-mentioned thermosetting component (B1).

In addition, as shown in FIG.1 (d), in the composite sheet (1) which has the structure by which the sheet | seat for resin film formation was pinched | interposed by the support body (I) and the support body (II), the surface of the sheet | seat for resin film formation After pasting (α) to the silicon wafer, the support (II) is not peeled off, and the support (II) and the resin film-forming sheet are laminated, and the resin film-forming sheet is thermoset, The gloss value measured from the surface (β ′) opposite to the silicon wafer of the formed resin film tends to be high. The gloss value indicates the gloss value of the surface (β ′) of the resin film formed using the composite sheet not having the support (II), or the surface of the resin film forming sheet by peeling the support (II). It becomes higher than the gloss value of the surface (β ′) of the resin film formed by thermosetting in a state where (β) is exposed.
That is, for example, even when the gloss value of the surface (β ′) of the resin film becomes low due to the use of a filler having a large average particle size as the filler (C), the composite sheet ( 1) After sticking to a silicon wafer, the support (II) is not peeled off, and the support (II) and the resin film-forming sheet are laminated, and the resin film-forming sheet is thermally cured. A resin film having high visibility for laser printing can be formed.
In order to make the resin film-forming sheet have thermosetting properties, the resin film-forming sheet may contain the above-described thermosetting component (B1).

Examples of the support (II) include the same support as the above-mentioned composite sheet of the present invention. Specifically, the above-mentioned resin film, a resin film having a release film, and a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer Etc.
When the support (II) is an adhesive sheet having an adhesive layer, the composite sheet (1) has a configuration in which the adhesive layer and the surface (β) of the resin film forming sheet are directly laminated. It is preferable to have. In this configuration, the pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive containing an energy ray-curable resin, and is preliminarily cured by irradiation with energy rays to form a pressure-sensitive adhesive layer. The support (II) and the resin film-forming sheet are The gloss value of the surface (β ′) of the formed resin film can be improved by thermosetting the resin film-forming sheet in the laminated state.

[Recycling method of silicon wafer]
As a method for reclaiming the silicon wafer by peeling the resin film-forming sheet from the laminate on which the silicon wafer and the surface (α) of the resin film-forming sheet of the present invention are adhered, for example, the following step (1) A method for reclaiming a silicon wafer having (2) is mentioned.
Step (1): The pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet having a base material and a pressure-sensitive adhesive layer is a surface (β) opposite to the surface (α) affixed to the silicon wafer of the resin film forming sheet of the laminate. ) Step (2) for pasting on the surface: Step for peeling the sheet for forming a resin film stuck on the silicon wafer by pulling the pressure-sensitive adhesive sheet stuck on the step (1)

The above silicon wafer recycling method has an excellent reworking property that when the silicon wafer is attached to the silicon wafer and then peeled off, the silicon wafer can be peeled without being damaged and without causing a residue. The property of the resin film forming sheet of the present invention is utilized.
Note that this silicon wafer recycling method is not limited to a laminate immediately after the silicon wafer and the surface (α) of the resin film forming sheet of the present invention are pasted, but after about 24 hours have passed since the pasting. The present invention can also be applied to a laminate in which the adhesion between the wafer and the resin film forming sheet is improved.

<Step (1)>
In the step (1), the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet having a base material and a pressure-sensitive adhesive layer is formed on the surface opposite to the surface (α) attached to the silicon wafer of the resin film forming sheet of the laminate ( β) is a step of applying on top.
Silicon wafers are not limited to wafers before being separated into individual pieces. For example, a silicon wafer is obtained by forming a groove from a surface opposite to the surface to be ground, such as a tip dicing method, and grinding until reaching the groove. It may be already separated into pieces by a method of dividing the chip into chips.

As an adhesive sheet used at this process, it has a base material and an adhesive layer. In addition, when the composite sheet (1) having the support (II) made of an adhesive sheet is attached to a silicon wafer, the support (II) may be used as the “adhesive sheet” in this step.
As the said base material, a resin film is preferable and the resin film illustrated by the item of the above-mentioned support body is mentioned.
The pressure-sensitive adhesive forming the pressure-sensitive adhesive layer is not particularly limited as long as the pressure-sensitive adhesive has an adhesive strength that can peel the resin film-forming sheet from the silicon wafer in the step (2).
Specific examples of the pressure sensitive adhesive include acrylic pressure sensitive adhesive, urethane pressure sensitive adhesive, and silicone pressure sensitive adhesive.

  The shape of the pressure-sensitive adhesive sheet is not particularly limited, but from the viewpoint of operability in the next step (2), the pressure-sensitive adhesive sheet has the same shape as the resin film-forming sheet or a shape larger than the resin film-forming sheet. Is preferred.

  As a method for attaching the surface (β) and the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet in this step, the method may be performed using a machine or may be performed manually.

  Note that the surface (α) of the resin film forming sheet included in the composite sheet of one embodiment of the present invention is attached to a silicon wafer, and an adhesive sheet such as a dicing sheet is already laminated on the surface (β) side as a support. In the case where the adhesive sheet is used, the adhesive sheet can be used as an adhesive sheet in this step.

<Step (2)>
In step (2), the adhesive sheet attached in step (1) is pulled to peel off the resin film forming sheet attached to the silicon wafer.
In this step, since the surface roughness (Ra) of the surface (α) affixed to the silicon wafer of the resin film forming sheet of the present invention is adjusted to the above range, the surface (β) in step (1) is adjusted. By pulling the adhesive sheet affixed to the resin film, the resin film forming sheet is also dragged together, and the resin film forming sheet can be peeled from the silicon wafer.

There is no restriction | limiting in particular as a peeling speed and a peeling angle of an adhesive sheet, It can set suitably.
In this step, the pressure-sensitive adhesive sheet may be pulled using a machine. However, from the viewpoint of operability, it is preferable to pull the pressure-sensitive adhesive sheet manually to separate the resin film forming sheet from the silicon wafer.

In this step, after the resin film forming sheet is peeled off, the surface of the silicon wafer may be washed with an organic solvent such as ethanol as necessary.
By passing through the above process, the silicon wafer once stuck with the resin film forming sheet can be regenerated.

<Measurement of mass average molecular weight (Mw) and number average molecular weight (Mn)>
Using a gel permeation chromatograph (manufactured by Tosoh Corporation, product name “HLC-8220GPC”), measurement was performed under the following conditions, and values measured in terms of standard polystyrene were used.
(Measurement condition)
Column: “TSK guard column HXL-L”, “TSK gel GMHXL (× 2)”, “TSK gel G2000HXL” (both manufactured by Tosoh Corporation), column temperature: 40 ° C.
・ Developing solvent: Tetrahydrofuran ・ Flow rate: 1.0 mL / min

<Average particle diameter of components in resin film forming composition>
It measured using the dynamic light-scattering type particle size distribution analyzer (the Nikkiso Co., Ltd. make, product name "Nanotrack Wave-UT151").

<Measurement of surface roughness (Ra)>
The surface roughness (Ra) of the surface of the measurement object was measured at a magnification of 10 times in the PSI mode using an optical interference type surface shape measuring device (product name “WYKO WT1100” manufactured by Veeco Metrology Group).

<Evaluation of reworkability of resin film forming sheet>
The support (I) of the composite sheet for forming a resin film prepared in Examples and Comparative Examples was removed, and the surface (α) of the exposed sheet for forming a resin film was # 2000 polished silicon wafer (diameter: 200 mm) , Thickness: 280 μm) was laminated and affixed while heating to 70 ° C. using a tape mounter (product name “Adwill RAD-3600 F / 12” manufactured by Lintec Corporation).
After pasting, the support (II) of the resin film-forming composite sheet is also removed at room temperature (25 ° C.), and a commercially available general-purpose dicing tape (manufactured by Lintec Corporation) on the surface of the exposed resin film-forming sheet , A pressure-sensitive adhesive layer surface having a trade name “Adwill D-510T”) was attached.
And by manually pulling the general-purpose dicing tape, whether the resin film forming sheet can be peeled together from the silicon wafer, and the presence or absence of the residue on the surface of the silicon wafer after peeling, The reworkability of the resin film forming sheet was evaluated based on the above criteria.
A: The resin film forming sheet could be completely peeled from the silicon wafer. Residue of the resin film forming sheet that could be visually confirmed was not observed on the peeled silicon wafer.
B: The resin film forming sheet could be peeled from the silicon wafer. A slight residue of the resin film-forming sheet was observed on the silicon wafer after peeling, but it could be completely removed by wiping with ethanol.
C: Even if the silicon wafer is damaged during the peeling, or the silicon wafer is peeled without being damaged, the resin film forming sheet that is difficult to wipe off with ethanol remains on the silicon wafer after the peeling. Things were confirmed.

<Measurement of gross value of resin film>
The support (I) of the composite sheet for resin film formation produced in the examples and comparative examples was removed, and the surface (α) of the exposed resin film formation sheet was # 2000 polished silicon wafer (diameter 200 mm, The film was laminated on a polished surface having a thickness of 280 μm, and a tape mounter (manufactured by Lintec Corporation, product name “Adwill RAD-3600 F / 12”) was attached while heating to 70 ° C.
After pasting, the support (II) of the resin film-forming composite sheet was also removed, and the resin film-forming sheet was cured by placing it in a heating oven at 130 ° C. for 2 hours to form a resin film on the silicon wafer.
Then, using a gloss meter (product name “VG 2000” manufactured by Nippon Denshoku Industries Co., Ltd.), in accordance with JIS Z 8741, the surface of the resin film formed from the side opposite to the side where the silicon wafer is located is 60 degrees. The specular gloss was measured. The value of the specular gloss was taken as the gloss value of the resin film.

<Measurement of light transmittance of resin film at wavelength 1250 nm>
The support (I) of the composite sheet for forming a resin film prepared in Examples and Comparative Examples is removed, and the surface (α) of the exposed sheet for forming a resin film is placed on a flat surface of a glass plate having a thickness of 2 mm. And laminated using a laminator while heating to 70 ° C.
After the application, the support (II) of the resin film-forming composite sheet was also removed, and the resin film-forming sheet was cured by placing it in a heating oven at 130 ° C. for 2 hours to form a resin film on the glass plate.
And the transmittance | permeability of the resin film on the said glass plate is measured using a spectrophotometer (The Shimadzu Corporation make, product name "UV-VIS-NIR SPECTROTOPOMETER UV-3600"), and the light transmittance of wavelength 1250nm (%) Was extracted.
For the measurement, a large sample chamber “MPC-3100” (product name) attached to the spectrophotometer was used, and measurement was performed without using a built-in integrating sphere. The light transmittance of the resin film at a wavelength of 1250 nm was calculated by taking the difference from the light transmittance of the wavelength of 1250 nm of only the glass plate measured in advance.

Example 1
Components of the types and blending amounts shown in Table 1 were added and diluted with methyl ethyl ketone to prepare a solution of a resin film forming composition having an active ingredient concentration of 51% by mass.
And as said support body (II), said resin on said peeling treatment surface of the polyethylene terephthalate (PET) film (The product name "SP-PET381031" by Lintec Corporation, thickness: 38 micrometers) by which peeling treatment was given. The film forming composition solution was applied and dried to form a resin film forming sheet having a thickness of 25 μm.
Furthermore, on the surface of the formed resin film forming sheet, as a support (I), release paper (trade name “SP-8LK Ao”, manufactured by Lintec Corporation, thickness: 88 μm, glassine paper is used. A polyolefin-coated, silicone-exfoliated treatment and an exfoliated surface of the exfoliated surface (Ra) = 370 nm) were bonded together, and a laminator (manufactured by Taisei Laminator Co., Ltd., product name “VA-400”) was attached. The laminate was made at room temperature (25 ° C.) to prepare a composite sheet for forming a resin film composed of support (I) / sheet for forming a resin film / support (II).

Comparative Example 1
A polyethylene terephthalate (PET) film (trade name, manufactured by Lintec Co., Ltd.) subjected to a release treatment as the support (I) on the exposed surface of the resin film-forming sheet formed in the same manner as in Example 1. Except that the peel-treated surface of “SP-PET251130” (thickness: 25 μm) was bonded, it was composed of support (I) / resin film forming sheet / support (II) in the same manner as in Example 1. A composite sheet for forming a resin film was prepared.

The detail of each component of Table 1 used for preparation of the composition for resin film formation is as follows.
<Polymer component (A)>
(A-1): an acrylic copolymer (BA /) obtained by copolymerizing methyl acrylate (MA), n-butyl acrylate (BA), glycidyl methacrylate (GMA), and 2-hydroxyethyl acrylate (HEA) MA / GMA / HEA = 37/28/20/15 (mass%), Mw = 800,000, Tg = −10.1 ° C.).
<Curable component (B)>
(B-1): Bisphenol A type epoxy resin (Mitsubishi Chemical Corporation, trade name “jER828”, epoxy equivalent = 184 to 194 g / eq, Mn = 370, viscosity at 25 ° C. = 120 to 150 P (12 to 15 Pa) S), a liquid epoxy resin, a compound corresponding to the component (B11)).
(B-2): Bisphenol A type epoxy resin (Mitsubishi Chemical Corporation, trade name “jER1055”, epoxy equivalent = 800 to 900 g / eq, Mn = 1600, solid epoxy resin, corresponding to the component (B11)) Compound).
(B-3) Dicyclopentadiene type epoxy resin (manufactured by DIC Corporation, trade name “Epicron HP-7200HH”, epoxy equivalent = 255-260 g / eq, compound with Mw less than 20,000, solid epoxy resin, the above components (Compound corresponding to (B11)).
(B-4): Dicyandiamide (manufactured by ADEKA Corporation, trade name “ADEKA HARDNER EH-3636AS”, amine-based curing agent, active hydrogen amount = 21 g / eq, compound corresponding to the component (B12)).
-(B-5): 2-Phenyl-4,5-dihydroxymethylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name “Curazole 2PHZ”, curing accelerator, compound corresponding to the component (B13)).
<Filler (C)>
(C-1): Silica filler (manufactured by Admatechs, trade name “SC2050MA”, average particle size = 500 nm).
<Colorant (D)>
(D-1): Carbon black (trade name “# MA650” manufactured by Mitsubishi Chemical Corporation, average particle size = 28 nm).
<Silane coupling agent (E)>
(E-1): Silane coupling agent (3-glycidoxypropylmethyldimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd., trade name “KBM-402”, Mn = 220.3).

  Table 1 shows the results of measuring and evaluating the physical properties of the resin film-forming sheets prepared in Examples and Comparative Examples based on the above-described method.

From Table 1, the resin film-forming sheet included in the composite sheet for forming a resin film produced in Example 1 which is an aspect of the present invention has excellent reworkability. Moreover, the resin film formed from the said resin film formation sheet also had a high gloss value and light transmittance at a wavelength of 1250 nm.
On the other hand, the resin film-forming sheet possessed by the resin film-forming composite sheet prepared in Comparative Example 1 has a small surface roughness (Ra) of the surface (α), and therefore can be peeled off after being attached to a silicon wafer. It was difficult and resulted in poor reworkability.

  The sheet for forming a resin film of one embodiment of the present invention is suitable as a material for forming a protective film that protects the back surface of a semiconductor chip, or as a material for forming an adhesive film that can be bonded to a die pad portion or other part.

1a, 1b, 1c, 1d Resin film forming composite sheet 10 Resin film forming sheet 11, 11 ′ Support 12 Jig adhesive layer

Claims (13)

A resin film forming sheet that is affixed to a silicon wafer to form a resin film on the silicon wafer,
Including 40 to 51.1% by mass of filler (C) with respect to the total amount of the resin film-forming sheet,
A resin film-forming sheet, wherein the surface roughness (Ra) of the surface (α) of the resin film-forming sheet on the side attached to the silicon wafer is 40 nm or more.   The sheet | seat for resin film formation of Claim 1 containing a polymer component (A) and a sclerosing | hardenable component (B).   The sheet | seat for resin film formation of Claim 2 in which a polymer component (A) contains an acrylic polymer (A1).   The sheet | seat for resin film formation of any one of Claims 1-3 containing a thermosetting component (B1).   The resin film-forming sheet according to any one of claims 1 to 4, wherein the filler (C) has an average particle diameter of 100 to 1000 nm.   The sheet for forming a resin film according to any one of claims 1 to 5, which is a sheet for forming a protective film for forming a protective film on a silicon wafer.   After the surface (α) of the resin film forming sheet is attached to a silicon wafer, the gloss value measured from the surface (β ′) of the resin film formed from the resin film forming sheet opposite to the silicon wafer is The sheet for forming a resin film according to any one of claims 1 to 6, which is 25 or more.   The composite sheet for resin film formation which has a sheet | seat for resin film formation of any one of Claims 1-7, and a support body. A resin film-forming sheet that is affixed to a silicon wafer and forms a resin film on the silicon wafer, and a support (I);
The resin film-forming sheet contains 40 to 51.1% by mass of a filler (C) with respect to the total amount of the resin film-forming sheet,
Resin film formation having a structure in which the surface (α) of the resin film forming sheet on the side to be bonded to the silicon wafer and the surface (i) of the support (I) having a surface roughness of 40 nm or more are directly laminated. Composite sheet.   The surface roughness (Ra) of the surface (α) of the resin film forming sheet that appears when the support (I) of the composite sheet for resin film formation is removed is 40 nm or more. The composite sheet for resin film formation as described.   The composite sheet for resin film formation of Claim 9 or 10 in which the said sheet | seat for resin film formation contains a thermosetting component (B1). On the surface (β) opposite to the surface (α) of the resin film-forming sheet, the second support (II) is directly laminated,
The composite sheet for resin film formation of Claim 9 or 10 in which the said sheet | seat for resin film formation contains a thermosetting component (B1).   The resin film according to claim 12, wherein the support (II) is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer, and the pressure-sensitive adhesive layer and the surface (β) of the resin film-forming sheet are directly laminated. Composite sheet for forming.